U.S. patent application number 10/195712 was filed with the patent office on 2003-02-06 for process for producing polyester, process for producing substituted a-hydroxy acid, and clostridium beijerinckii strain hica432.
Invention is credited to Kozaki, Shinya, Minami, Masato.
Application Number | 20030027294 10/195712 |
Document ID | / |
Family ID | 27482437 |
Filed Date | 2003-02-06 |
United States Patent
Application |
20030027294 |
Kind Code |
A1 |
Minami, Masato ; et
al. |
February 6, 2003 |
Process for producing polyester, process for producing substituted
a-hydroxy acid, and clostridium beijerinckii strain hica432
Abstract
A process for producing a polyester, the process comprising the
steps of (1) fermenting a saccharide with a microorganism to obtain
at least one substituted .alpha.-hydroxy acid represented by the
formula: HO--CHR--COOH (wherein R represents a hydrocarbon group
having 1 to 10 carbon atoms), and (2) polymerizing the substituted
.alpha.-hydroxy acid or a derivative thereof.
Inventors: |
Minami, Masato; (Kanagawa,
JP) ; Kozaki, Shinya; (Tokyo, JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
27482437 |
Appl. No.: |
10/195712 |
Filed: |
July 16, 2002 |
Current U.S.
Class: |
435/135 ;
528/274 |
Current CPC
Class: |
C12P 7/42 20130101; C12R
2001/145 20210501; C12P 7/625 20130101; C12N 1/205 20210501; C12P
7/56 20130101 |
Class at
Publication: |
435/135 ;
528/274 |
International
Class: |
C12P 007/62; C08G
063/78; C08G 063/82; C08G 063/87 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 16, 2001 |
JP |
215388/2001 |
Jul 16, 2001 |
JP |
215392/2001 |
Jul 16, 2001 |
JP |
215393/2001 |
Jul 16, 2001 |
JP |
215428/2001 |
Claims
What is claimed is:
1. A process for producing a polyester, comprising the steps of:
(1) fermenting a saccharide with a microorganism to obtain at least
one substituted .alpha.-hydroxy acid represented by the formula:
HO--CHR--COOH wherein R represents a hydrocarbon group having 1 to
10 carbon atoms; and (2) polymerizing the substituted
.alpha.-hydroxy acid or a derivative thereof.
2. The process for producing a polyester according to claim 1,
wherein said saccharide is glucose or xylose.
3. The process for producing a polyester according to claim 2,
which further comprises, prior to the steps (1) and (2), the step
of (3) subjecting a raw material containing cellulose or
hemicellulose, to hydrolysis to obtain the glucose or xylose.
4. The process for producing a polyester according to claim 1,
wherein said saccharide is starch.
5. The process for producing a polyester according to claim 1,
wherein said saccharide is starch or glucose, and said at least one
substituted .alpha.-hydroxy acid is selected from the group
consisting of lactic acid (the R is a methyl group),
.beta.-phenyllactic acid (the R is a benzyl group) and
2-hydroxyisocaproic acid (the R is an isobutyl group).
6. The process for producing a polyester according to claim 1,
wherein said at least one substituted .alpha.-hydroxy acid contains
at least .beta.-phenyllactic acid (the R is a benzyl group).
7. The process for producing a polyester according to claim 1,
wherein said at least one substituted .alpha.-hydroxy acid contains
at least 2-hydroxyisocaproic acid (the R is an isobutyl group).
8. The process for producing a polyester according to claim 1,
wherein said saccharide is xylose, and said at least one
substituted .alpha.-hydroxy acid is at leas one of
.beta.-phenyllactic acid (the R is a benzyl group) and
2-hydroxyisocaproic acid (the R is an isobutyl group).
9. The process for producing a polyester according to claim 1,
wherein said microorganism used in the step (1) is an anaerobic
bacterium.
10. The process for producing a polyester according to claim 9,
wherein the fermentation in the step (1) is carried out in the
presence of pyruvic acid.
11. The process for producing a polyester according to claim 9,
wherein said anaerobic bacterium is a bacterium belonging to the
genus Clostridium.
12. The process for producing a polyester according to claim 11,
wherein said bacterium belonging to the genus Clostridium is
Clostridium beijerinckii strain HICA432, FERMP-18373.
13. The process for producing a polyester according to claim 1,
wherein said substituted .alpha.-hydroxy acid is a cyclic dimer
lactide, and which process further comprises, prior to the step-(2)
polymerization, the step of (4) dehydrating the substituted
.alpha.-hydroxy acid by two molecules to effect cyclic
diesterification to obtain the cyclic dimer lactide.
14. The process for producing a polyester according to claim 1,
wherein said polyester contains at lest one of repeating units
represented by the following Formulas (I) to (III). 5
15. A process for producing a substituted .alpha.-hydroxy acid,
comprising fermenting a saccharide with a microorganism.
16. The process for producing a substituted .alpha.-hydroxy acid
according to claim 15, wherein said microorganism is an anaerobic
bacterium.
17. The process for producing a substituted .alpha.-hydroxy acid
according to claim 16, wherein the step of obtaining said
substituted .alpha.-hydroxy acid is carried out by fermentation
with an anaerobic bacterium in the presence of pyruvic acid.
18. The process for producing a substituted .alpha.-hydroxy acid
according to claim 16, wherein said anaerobic bacterium is a
bacterium belonging to the genus Clostridium.
19. The process for producing a substituted .alpha.-hydroxy acid
according to claim 18, wherein said bacterium belonging to the
genus Clostridium is Clostridium beijerinckii strain HICA432,
FERMP-18373.
20. A Clostridium beijerinckii strain HICA432, FERMP-18373.
21. A Clostridium beijerinckii strain HICA432, FERMP-18373, used to
form a substituted .alpha.-hydroxy acid from a saccharide.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a process for producing a
polyester, and also relates to a method of recycling hemicellulose
and cellulose.
[0003] 2. Related Background Art
[0004] Conventional general-purpose plastic products are polymeric
compounds synthesized chiefly from petroleum resoucrces. More
specifically, polymeric compounds such as polyester, polystyrene,
nylon, polyethylene, polyvinyl chloride, polyimide and
polycarbonate are, in almost all cases, produced from monomers
obtained using petroleum as a raw material.
[0005] The petroleum, however, is a limited recource, and is
foreseen to become depleted before long. Accordingly, a technique
is earnestly desired by which general-purpose plastic products are
produced from new materials substitutive for the petroleum, i.e.,
renewable materials.
[0006] Meanwhile, the recycling of wastepaper or the like is put
forward with an increase in demand for paper which is due to the
spread of personal computers and office automation machinery, the
use of paper containers and so forth. However, the number of times
for recycling is limited because paper fibres become short fibers,
and it is greatly questioned how unrenewable wastepaper or the like
be disposed of. On the other hand, from the viewpoint of effective
utilization of resources, it is sought to utilize wastepaper or the
like other than thermal recycling. Paper is chiefly composed of
cellulose. It is on studies to decompose this cellulose so as to be
reused.
[0007] The cellulose is produced in an amount of 10.sup.9 to
10.sup.11 tons per year, and is used in a large quantity for
extensive purposes such as structural materials, fillers, food
additives and further adhesives or the like. With such use, waste
cellulose also increases year by year.
[0008] Hemicellulose, which is present in vegetable tissues in a
proportion of 20 to 30%, also mingles into paper without being
removed in the course of the manufacture of pulp. Its quantity
reaches as large as about 20% when it is in a large quantity. Thus,
when the effective utilization of wastepaper is taken into account,
the effective utilization of the hemicellulose component has come
into question not ignorable. Also, hemicellulose discarded in the
course of the manufacture of cellulose has been increasing on and
on with the increase in demand for paper.
[0009] Meanwhile, starch is a polymeric compound formed by
dehydrating polymerization of D-glucose, and is an important
polysaccharide, inclusive of cellulose. The starch is produced from
potatoes, sweet potatoes, corn and so forth. Its yield (the crop of
corn) in the whole world is about four to five hundred million tons
per year. It is produced in the largest quantity among natural
resources, and is a renewable resource. Accordingly, the starch is
promising as a new resource substitutive for the petroleum if
general-purpose plastic products can be manufactured from the
starch.
[0010] As techniques by which the waste cellulose is decomposed and
reused, known are, e.g., a method in which hydrocarbons such as
methane and ethane are derived from cellulose (Japanese Patent
Application Laid-open No. 5-213778) and a method in which alcohols
are produced from cellulose (Japanese Patent Application Laid-open
No. 11-299479).
[0011] As techniques in which the waste hemicellulose is utilized,
studies are made on food additives (Japanese Patent Applications
Laid-open No. 5-17503 and No.5-43470), foaming agents (Japanese
Patent Application Laid-open No. 5-244880), sizing agents for fiber
texturing (Japanese Patent Application Laid-open No. 5-263367),
cosmetic materials (Japanese Patent Application Laid-open No.
6-157238), fiber materials (Japanese Patent Application Laid-open
No. 6-220213) and so forth.
[0012] Incidentally, production of thermosetting resin materials
from lignocellulose is disclosed in Japanese Patent Application
Laid-open No. 6-126715, which are manufactured for use in adhesives
in view of physical properties.
[0013] In order to deal with future further increase in these
wastes, a novel technical development is necessary which enables
more efficient recycling. Accordingly, the present inventors have
taken note of the fact that the increasing wastes are pulp, paper,
waste starch and so forth on the one hand and the fact that plastic
materials substitutive for the petroleum are sought on the other
hand, and have made studies on the production of plastics from
saccharides. If plastics can be produced from saccharides, useful
industrial produces can be provided using abundant starting
materials, and also the depletion of petroleum resources can be
avoided and any environmental pollution caused by wastes can be
eliminated.
SUMMARY OF THE INVENTION
[0014] Accordingly, an object of the present invention is to
provide a practical process by which saccharides can be converted
into plastics.
[0015] Stated specifically, an object of the present invention is
to provide a process for producing a plastic material obtained
using hemicellulose and cellulose as raw materials.
[0016] Another object of the present invention is to provide a
method of recycling hemicellulose and cellulose.
[0017] Still another object of the present invention is to obtain
high-quality plastics using glucans such as cellulose and starch as
starting materials.
[0018] The present invention is a process for producing a
polyester, the process comprising the steps of:
[0019] (1) fermenting a saccharide with a microorganism to obtain
at least one substituted .alpha.-hydroxy acid represented by the
formula: HO--CHR--COOH (wherein R represents a hydrocarbon group
having 1 to 10 carbon atoms); and
[0020] (2) polymerizing the substituted .alpha.-hydroxy acid or a
derivative thereof.
[0021] As the saccharide, starch, glucose or xylose may be
used.
[0022] In the case when the saccharide is glucose or xylose, the
process may preferably have, prior to the steps (1) and (2), the
step of (3) subjecting a raw material containing cellulose or
hemicellulose, to hydrolysis to obtain glucose or xylose.
[0023] In the case when the saccharide is starch or glucose, the
above at least one substituted .alpha.-hydroxy acid is selected
from the group consisting of lactic acid (the R is a methyl group),
.beta.-phenyllactic acid (the R is a benzyl group) and
2-hydroxyisocaproic acid (the R is an isobutyl group).
[0024] The microorganism used in the step (1) may preferably be an
anaerobic bacterium, and the fermentation in that step may
preferably be carried out in the presence of pyruvic acid.
[0025] The substituted .alpha.-hydroxy acid may preferably be a
cyclic dimer lactide, and the process may preferably have, prior to
the step-(2) polymerization, the step of (4) dehydrating the
substituted .alpha.-hydroxy acid by two molecules to effect cyclic
diesterification to obtain the cyclic dimer lactide.
[0026] The polyester may further contain at lest one of repeating
units represented by the following Formulas (I) to (III). 1
[0027] The present invention is also a process for producing a
substituted .alpha.-hydroxy acid, comprising fermenting a
saccharide with a microorganism.
[0028] The microorganism may preferably be an anaerobic bacterium,
and the fermentation may be carried out in the presence of pyruvic
acid.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] The present invention is a process for producing a
polyester, which has the steps of:
[0030] (1) fermenting a saccharide with a microorganism to obtain
at least one substituted .alpha.-hydroxy acid represented by the
formula: HO--CHR--COOH (wherein R represents a hydrocarbon group
having 1 to 10 carbon atoms); and
[0031] (2) polymerizing the substituted .alpha.-hydroxy acid or a
derivative thereof.
[0032] The step (1) may specifically include the following four
embodiments.
[0033] A first embodiment is a polyester production process which
comprises hydrolyzing a glucan to obtain glucose, fermenting the
glucose with a microorganism to produce the substituted
.alpha.-hydroxy acid, and polymerizing the substituted
.alpha.-hydroxy acid or a substituted .alpha.-hydroxy acid
derivative.
[0034] A second embodiment is a polyester production process which
comprises fermenting starch with a microorganism to produce the
substituted .alpha.-hydroxy acid, and polymerizing the substituted
.alpha.-hydroxy acid or a substituted .alpha.-hydroxy acid
derivative.
[0035] A third embodiment is a polyester production process which
comprises hydrolyzing a material containing at least hemicellulose,
to obtain xylose, fermenting the xylose with a microorganism to
produce the substituted .alpha.-hydroxy acid, and polymerizing the
substituted .alpha.-hydroxy acid or a substituted .alpha.-hydroxy
acid derivative.
[0036] A fourth embodiment is a polyester production process which
comprises hydrolyzing a material containing hemicellulose and
cellulose, to obtain xylose and glucose, fermenting the xylose and
glucose with a microorganism to produce the substituted
.alpha.-hydroxy acid, and polymerizing the substituted
.alpha.-hydroxy acid or a substituted .alpha.-hydroxy acid
derivative.
[0037] As the microorganism used in the above first to fourth
embodiments, an anaerobic bacterium is preferred. The anaerobic
bacterium may preferably be a bacterium of the genus Clostridium.
The bacterium of the genus Clostridium may preferably be
Clostridium beijerinckii strain HICA432, FERMP-18373, capable of
forming the substituted .alpha.-hydroxy acid from glucose.
[0038] In the production process of the present invention,
substituted .alpha.-hydroxy acids having a purity high enough to be
usable as a polyester monomer can efficiently be produced from a
saccharide such as starch, glucose, xylose or a mixture of glucose
and xylose by utilizing a microorganism. As the result, a
high-quality plastic can be obtained using glucans such as
cellulose and starch, cellulose, hemicellulose and a mixture of
glucose and xylose as starting materials. Hence, a polyester can be
produced which is obtained using waste cellulose, waste
hemicellulose, waste starch and so forth as raw materials. Thus,
these wastes can be recycled.
[0039] A. The Step of Obtaining Substituted .alpha.-Hydroxy
Acid:
[0040] First Embodiment
[0041] The process of the first embodiment comprises the step of
hydrolyzing a glucan to obtain glucose, and the step of fermenting
the glucose with a microorganism to obtain at least one substituted
.alpha.-hydroxy acid represented by the formula: HO--CHR--COOH
(wherein R represents a hydrocarbon group having 1 to 10 carbon
atoms).
[0042] The respective steps are described below.
[0043] (Glucose from Glucan)
[0044] As the glucan serving as a starting material, there are no
particular limitations thereon as long as it can be hydrolyzed to
form glucose. However, from the viewpoint of the recycling of
glucan, cellulose and starch are preferred, which are produced in a
large quantity and have not usefully been put to recycling.
[0045] The conversion of cellulose into glucose may be made by,
e.g., a method of decomposing the cellulose with an enzyme such as
cellulase, a method of decomposing it with an acid such as sulfuric
acid or hydrochloric acid, or a method of decomposing it with
supercritical water.
[0046] As the cellulose used as a raw material when the glucose is
obtained from the cellulose, any commercially available cellulose
may be used as a matter of course, and any waste cellulose obtained
by treating waste paper and woods such as waste wood appropriately
may also be used. Thus, the present invention can make a new route
for the recycling of waste cellulose.
[0047] The conversion of starch into glucose may be made by, e.g.,
a method of hydrolyzing the starch with a dilute acid such as
dilute sulfuric acid, a method of hydrolyzing it with an enzyme
such as amylase or maltase, or a method of hydrolyzing it with
supercritical water.
[0048] As the starch used as a raw material when the glucose is
obtained from the starch, any commercially available starch may be
used as a matter of course, and any waste starch obtained by
treating potatoes, sweet potatoes and corn appropriately may also
be used. Thus, the present invention can make a new route for the
recycling of waste starch.
[0049] (Substituted .alpha.-Hydroxy Acid from Glucose)
[0050] The conversion of glucose into substituted .alpha.-hydroxy
acids is carried out by anaerobic fermentation attributable to a
microorganism. Incidentally, the production of hydroxy acids by
microorganisms is disclosed in Japanese Patent Applications
Laid-open No. 5-336981 and No. 7-327692. There, however, is no
specific disclosure as to any microorganisms capable of producing
2-hydroxyisocaproic acid from glucose.
[0051] As the microorganism, there are only few microorganisms
isolated and identified as strains capable of producing the
substituted .alpha.-hydroxy acid from glucose, and also these can
only be produced in a low efficiency. Accordingly, we have made
extensive screening on new strains. For example, the
2-hydroxyisocaproic acid has been picked up as the substituted
.alpha.-hydroxy acid, and, using a VL culture medium (10 g/l of
peptone, 5 g/l of yeast extract, 2 g/l of meat extract, 5 g/l of
NaCl and 2 g/l of cysteine hydrochloride) to which 5 g/l of glucose
and 5 g/l of calcium carbonate have been added, and under anaerobic
conditions of 30.degree. C., screening has been made on strains
having the ability to produce the 2-hydroxyisocaproic acid.
[0052] As the result, we have succeeded in obtaining a Clostridium
beijerinckii strain HICA432 as a strain capable of producing
2-hydroxyisocaproic acid from glucose, which is a bacterium of the
genus Clostridium such as Clostridium beijerinckii.
[0053] The above strain is kept deposited as of Jun. 6, 2001 in
International Patent Organism Depositary (IPOD), National Institute
of Advanced Industrial Science and Technology (AIST) (Deposition
No. FERMP-18373).
[0054] On the Clostridium beijerinckii strain HICA432, FERMP-18373,
thus obtained, products formed from glucose have further been
analyzed to find that, in addition to the 2-hydroxyisocaproic acid
as the substituted .alpha.-hydroxy acid represented by HO-CHR-COOH
(R is an isobutyl group), at least lactic acid (R is a methyl
group) and .beta.-phenyllactic acid (R is a benzyl group) have been
produced. Hence, polyester can be produced from at least one of
these substituted .alpha.-hydroxy acids.
[0055] Stated specifically, when the substituted .alpha.-hydroxy
acids produced from glucose by the aid of the strain HICA432 are
used, the polyester obtained has at lest one of the repeating units
represented by the above Formulas (I) to (III).
[0056] A mixture of the substituted .alpha.-hydroxy acids produced
from glucose by the aid of the strain HICA432 may further
optionally be purified to obtain, e.g., one containing
substantially only .beta.-phenyllactic acid, one containing
substantially only 2-hydroxyisocaproic acid, one containing at
least .beta.-phenyllactic acid, and one containing at least
2-hydroxyisocaproic acid.
[0057] Where at least one substituted .alpha.-hydroxy acid is so
purified as to contain substantially only the .beta.-phenyllactic
acid, the polyester obtained chiefly contains the structure
represented by Formula (II). In this case, the polyester obtained
has a benzyl group in the side chain, and hence is presumed to have
superior heat resistance. Also, the .beta.-phenyllactic acid has a
high polymerization activity, and hence can ensure a sufficient
degree of polymerization of the polyester obtained.
[0058] What is meant by "chiefly contain" is that the product
preferably comprise 60 mol % or more, more preferably 70 mol % or
more, still more preferably 80 mol % or more, and most preferably
90 mol % or more.
[0059] Where at least one substituted .alpha.-hydroxy acid is so
purified as to contain substantially only the 2-hydroxyisocaproic
acid, the polyester obtained chiefly contains the structure
represented by Formula (III). In this case, the polyester obtained
has an isobutyl group in the side chain, and hence is presumed to
have a low glass transition temperature and a superior mechanical
properties. Also, the 2-hydroxyisocaproic acid has a high
polymerization activity, and hence can ensure a sufficient degree
of polymerization of the polyester obtained.
[0060] Where at least one substituted .alpha.-hydroxy acid is so
purified as to contain at least the .beta.-phenyllactic acid and
where, e.g., it is so purified as to contain lactic acid and
.beta.-phenyllactic acid, a polyester can be produced which chiefly
contains the structures represented by Formulas (I) and (II). In
this case, the polyester obtained has a methyl group and a benzyl
group in the side chain, and hence is presumed to have well
balanced moldability and heat resistance.
[0061] Where at least one substituted .alpha.-hydroxy acid is so
purified as to contain at least the 2-hydroxyisocaproic acid and
where, e.g., it is so purified as to contain lactic acid and
2-hydroxyisocaproic acid, a polyester can be produced which chiefly
contains the structures represented by Formulas (I) and (III). In
this case, the polyester obtained has a methyl group and an
isobutyl group in the side chain, and hence is presumed to have
well balanced moldability and mechanical properties.
[0062] Where at least one substituted .alpha.-hydroxy acid is so
purified as to contain at least the .beta.-phenyllactic acid and
the 2-hydroxyisocaproic acid, a polyester can be produced which
chiefly contains the structures represented by Formulas (II) and
(III). In this case, the polyester obtained has a benzyl group and
an isobutyl group in the side chain, and hence is presumed to have
well balanced heat resistance and mechanical properties. Also, the
.beta.-phenyllactic acid and 2-hydroxyisocaproic acid have a high
polymerization activity, and hence can ensure a sufficient degree
of polymerization of the polyester obtained.
[0063] The substituted .alpha.-hydroxy acids may also individually
be purified, and the purified products obtained may be mixed in
stated quantities to produce a polyester. In this case, a wide
range of physical properties of the polyester can be
materialized.
[0064] The Clostridium beijerinckii strain HICA432, FERMP-18373,
can produce the substituted .alpha.-hydroxy acid at a high rate.
Stated specifically, when compared under the same growth
conditions, the strain HICA432 can achieve in few days the quantity
of the substituted .alpha.-hydroxy acid any of absolutely anaerobic
bacteria conventionally commonly known and having the ability to
produce substituted .alpha.-hydroxy acids produces in few weeks to
few months. Hence, a sufficient production efficiency of the
substituted .alpha.-hydroxy acid can be materialized.
[0065] The Clostridium beijerinckii strain HICA432, FERMP-18373,
also has a high growth rate. Stated specifically, any of commonly
available absolutely anaerobic bacteria reaches the initial
logarithmic growth phase in about a month after inoculation,
whereas the strain HICA432 reaches the the initial logarithmic
growth phase in few days. Hence, the quantity of the bacterial body
necessary for producing the substituted .alpha.-hydroxy acid in a
sufficient quantity can be ensured with ease.
[0066] The fermentation for converting the glucose into the
substituted .alpha.-hydroxy acid is carried out by adding the
strain to a culture fluid containing the glucose as a chief carbon
source and also nitrogen, phosphorus, mineral(s), vitamin(s) and so
force added thereto as nutrients, and maintaining it under
anaerobic conditions.
[0067] The above strain is an absolutely anaerobic bacterium which
dies out in the presence of oxygen, and hence the anaerobic
conditions must strictly be set up. After the culture medium has
been injected, the gaseous-phase portion in a culturing container
hermetically stoppered with a butyl rubber stopper or the like not
transmitting any gases is displaced with nitrogen, carbon dioxide,
hydrogen or the like. Any oxygen in the culture medium must also be
removed using a reducing agent such as cysteine, sodium
thioglycolate or sodium sulfide or by heat treatment or exposure to
nitrogen.
[0068] The concentration of glucose in the culture fluid may be set
in accordance with the type of the microorganism used. In order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity, the glucose may usually be in a
concentration of 0.1% by weight or more, and preferably 0.5% by
weight or more. On the other hand, in order to make any by-products
less develop, it may usually be in a concentration of 10% by weight
or less, and preferably 5% by weight or less.
[0069] Any auxiliary carbon sources are unnecessary, and the
glucose may be used as a single carbon source. As nitrogen sources,
usable are organic or inorganic nitrogen sources such as urea,
ammonia, ammonium sulfate and ammonium nitrate, and natural
nitrogen sources such as corn steep liquor, peptone, meat extract
and yeast extract. As inorganic salts, usable are potassium
phosphate, sodium phosphate, magnesium sulfate, manganese sulfate,
ferrous sulfate, potassium chloride and sodium chloride.
[0070] Fermentation temperature may usually be set at 15.degree. C.
or above, and preferably 20.degree. C. or above, in order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity. On the other hand, in order to make any
by-products less develop and prevent the strain from dying out, it
may usually be set at 38.degree. C. or below, and preferably
37.degree. C. or below.
[0071] The culture fluid may also usually have a pH of
approximately from 5 to 7 as suitable temperature, which may
appropriately be set in accordance with the nature of the
microorganism.
[0072] Further with regard to fermentation time, which depends on
the type of the microorganism, in the case of the strain HICA432
the fermentation can be completed in three days to a week, or,
under selected conditions for pre-fermentation, in a day to three
days.
[0073] A phenomenon has also been found in which, with progress of
fermentation, the strain HICA432 changes the proportion of the
substituted .alpha.-hydroxy acids it produces. For example, where
the fermentation is performed under the conditions described above,
the lactic acid, .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid are produced in substantially the same molar number in the
former term of the fermentation (e.g., up to the third day after
the start of fermentation), and their molar concentration in the
culture medium increases on similarly for all of them. In contrast,
in the latter term of the fermentation (e.g., on the third day and
later after the start of fermentation), the molar concentration of
the lactic acid, .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid in the culture medium becomes constant and only that of the
lactic acid increases.
[0074] Such performance may be utilized so that the substituted
.alpha.-hydroxy acids can more efficiently be purified. For
example, where the .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid are chiefly needed, a mixture of substituted .alpha.-hydroxy
acids produced in the former term of the fermentation is purified.
On the other hand, where the lactic acid is chiefly needed, a
mixture of substituted .alpha.-hydroxy acids produced in the latter
term of the fermentation is purified.
[0075] It has further been found that such fermentation performance
can be controlled by adding pyruvic acid to the culture medium. For
example, where the fermentation is performed adding pyruvic acid to
the culture medium, the lactic acid, .beta.-phenyllactic acid and
2-hydroxyisocaproic acid are produced in substantially the same
molar number in the former term of the fermentation (e.g., up to
the third day after the start of fermentation), and their molar
concentration in the culture medium increases on similarly for all
of them. In contrast, in the latter term of the fermentation (e.g.,
on the third day and later after the start of fermentation), the
molar concentration of the 2-hydroxyisocaproic acid in the culture
medium becomes constant, whereas the molar concentration of the
lactic acid decreases and that of the .beta.-phenyllactic acid
increases.
[0076] Such performance may be utilized so that the substituted
.alpha.-hydroxy acids can more efficiently be purified. For
example, where the .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid are chiefly needed, a mixture of substituted .alpha.-hydroxy
acids produced in the former term of the fermentation is purified.
On the other hand, where only the .beta.-phenyllactic acid is
chiefly needed, a mixture of substituted .alpha.-hydroxy acids
produced in the latter term of the fermentation is purified.
[0077] Here, the pyruvic acid may preferably be in a concentration
of 0.1% by weight or more, and more preferably 0.5% by weight or
more, in order to well control the formation of lactic acid. On the
other hand, in order to make any by-products less develop, it may
preferably be in a concentration of 10% by weight or less, and more
preferably 5% by weight or less.
[0078] Second Embodiment
[0079] The process of the second embodiment comprises the step of
fermenting starch with a microorganism to obtain at least one
substituted .alpha.-hydroxy acid represented by the formula:
HO-CHR-COOH (wherein R represents a hydrocarbon group having 1 to
10 carbon atoms).
[0080] This step is described below.
[0081] (Substituted .alpha.-Hydroxy Acid from Starch)
[0082] As the starch as a raw material, any commercially available
starch may be used as a matter of course, and any waste starch
obtained by treating potatoes, sweet potatoes and corn
appropriately may also be used. Thus, the present invention can
make a new route for the recycling of waste starch.
[0083] The step of obtaining substituted .alpha.-hydroxy acids
directly from starch without passing through the glucose is carried
out by anaerobic fermentation attributable to a microorganism.
Incidentally, the production of hydroxy acids by microorganisms is
disclosed in Japanese Patent Applications Laid-open No. 5-336981,
No. 7-327692 and No. 2000-300284. There, however, is no specific
disclosure as to any microorganisms capable of producing
substituted .alpha.-hydroxy acids from starch.
[0084] As the microorganism, there are only few microorganisms
isolated and identified as strains capable of producing the
substituted .alpha.-hydroxy acid from glucose, and also these can
only be produced in a low efficiency. Accordingly, we have made
extensive screening on new strains. Here, for the reasons of
experiment efficiency and so forth, not the direct screening of
strains capable of converting the starch into the substituted
.alpha.-hydroxy acid, but screening has been first made on strains
capable of converting glucose into the substituted .alpha.-hydroxy
acid, and then, from among the strains obtained, screening has
further been made on strains capable of converting the starch into
the substituted .alpha.-hydroxy acid.
[0085] For example, the 2-hydroxyisocaproic acid has been picked up
as the substituted .alpha.-hydroxy acid, and, using a VL culture
medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l of meat
extract, 5 g/l of NaCl and 2 g/l of cysteine hydrochloride) to
which 5 g/l of glucose and 5 g/l of calcium carbonate have been
added, and under anaerobic conditions of 30.degree. C., screening
has been made on strains having the ability to produce the
2-hydroxyisocaproic acid.
[0086] Then, on the strains thus obtained, the ability to produce
substituted .alpha.-hydroxy acids from starch has been studied.
[0087] As the result, we have succeeded in obtaining the
Clostridium beijerinckii strain HICA432 as a strain capable of
producing 2-hydroxyisocaproic acid from starch, which is a
bacterium of the genus Clostridium such as Clostridium
beijerinckii.
[0088] On the Clostridium beijerinckii strain HICA432, FERMP-18373,
thus obtained, products formed from starch have further been
analyzed to find that, like the products formed from the glucose
described in the first embodiment, in addition to the
2-hydroxyisocaproic acid as the substituted .alpha.-hydroxy acid
represented by HO--CHR--COOH (R is an isobutyl group), at least
lactic acid (R is a methyl group) and .beta.-phenyllactic acid (R
is a benzyl group) have been produced. Hence, polyester can be
produced from at least one of these substituted .alpha.-hydroxy
acids.
[0089] Stated specifically, also when the substituted
.alpha.-hydroxy acids produced from starch by the aid of the strain
HICA432 are used, the polyester obtained has at lest one of the
repeating units represented by the above Formulas (I) to (III).
[0090] A mixture of the substituted .alpha.-hydroxy acids produced
from starch by the aid of the strain HICA432 may optionally be
purified in the same manner as in the first embodiment.
[0091] The growth rate of the strain HICA432 and the production
rate of the substituted .alpha.-hydroxy acids have also been found
to be the same as those of the strain used in the first
embodiment.
[0092] The fermentation for converting the starch into the
substituted .alpha.-hydroxy acid is carried out by adding the
strain to a culture fluid containing the starch as a chief carbon
source and also nitrogen, phosphorus, mineral(s), vitamin(s) and so
force added thereto as nutrients, and maintaining it under
anaerobic conditions.
[0093] The above strain is an absolutely anaerobic bacterium which
dies out in the presence of oxygen, and hence the anaerobic
conditions must strictly be set up. After the culture medium has
been injected, the gaseous-phase portion in a culturing container
hermetically stoppered with a butyl rubber stopper or the like not
transmitting any gases is displaced with nitrogen, carbon dioxide,
hydrogen or the like. Any oxygen in the culture medium must also be
removed using a reducing agent such as cysteine, sodium
thioglycolate or sodium sulfide or by heat treatment or exposure to
nitrogen.
[0094] The concentration of starch in the culture fluid may be set
in accordance with the type of the microorganism used. In order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity, the starch may usually be in a concentration
of 0.1% by weight or more, and preferably 0.5% by weight or more.
On the other hand, in order to make any by-products less develop,
it may usually be in a concentration of 10% by weight or less, and
preferably 5% by weight or less.
[0095] Any auxiliary carbon sources are unnecessary, and the starch
may be used as a single carbon source. As nitrogen sources, usable
are organic or inorganic nitrogen sources such as urea, ammonia,
ammonium sulfate and ammonium nitrate, and natural nitrogen sources
such as corn steep liquor, peptone, meat extract and yeast extract.
As inorganic salts, usable are potassium phosphate, sodium
phosphate, magnesium sulfate, manganese sulfate, ferrous sulfate,
potassium chloride and sodium chloride.
[0096] Fermentation temperature may usually be set at 15.degree. C.
or above, and preferably 20.degree. C. or above, in order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity. On the other hand, in order to make any
by-products less develop and prevent the strain from dying out, it
may usually be set at 38.degree. C. or below, and preferably
37.degree. C. or below.
[0097] The culture fluid may also usually have a pH of
approximately from 5 to 7 as suitable temperature, which may
appropriately be set in accordance with the nature of the
microorganism.
[0098] Further with regard to fermentation time, which depends on
the type of the microorganism, in the case of the strain HICA432
the fermentation can be completed in three days to a week, or,
under selected conditions for pre-fermentation, in a day to three
days.
[0099] A phenomenon has also been found in which, with progress of
fermentation, the strain HICA432 changes the proportion of the
substituted .alpha.-hydroxy acids it produces. For example, where
the fermentation is performed under the conditions described above,
the lactic acid, .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid are produced in substantially the same molar number in the
former term of the fermentation (e.g., up to the third day after
the start of fermentation), and their molar concentration in the
culture medium increases on similarly for all of them. In contrast,
in the latter term of the fermentation (e.g., on the third day and
later after the start of fermentation), that of the lactic acid
decreases.
[0100] Such performance may be utilized so that the substituted
.alpha.-hydroxy acids can more efficiently be purified. For
example, where the .beta.-phenyllactic acid and 2-hydroxyisocaproic
acid are chiefly needed, a mixture of substituted .alpha.-hydroxy
acids produced in the former term of the fermentation is
purified.
[0101] 3. Third Embodiment
[0102] The process of the third embodiment comprises the step of
hydrolyzing a material containing at least hemicellulose, to obtain
xylose, and the step of fermenting the xylose with a microorganism
to obtain at least one substituted .alpha.-hydroxy acid represented
by the formula: HO--CHR--COOH (wherein R represents a hydrocarbon
group having 1 to 10 carbon atoms).
[0103] These steps are described below.
[0104] (Xylose from Hemicellulose)
[0105] As materials containing the raw material hemicellulose, any
commercially available hemicellulose may be used as a matter of
course, and any waste hemicellulose obtained by appropriately
treating waste paper, woods such as waste wood as well as pulp
waste liquor may also be used. Thus, the establishment of a method
of synthesizing polyester from hemicellulose can make a new route
for the recycling of waste hemicellulose. In this regard, the
polyester production process of the present invention is at the
same time a useful method of recycling hemicellulose.
[0106] The conversion of hemicellulose into xylose may be made by,
e.g., a method of decomposing the hemicellulose with an enzyme such
as xylanase, a method of decomposing it with an acid such as
sulfuric acid or hydrochloric acid, or a method of decomposing it
with supercritical water.
[0107] (Substituted .alpha.-Hydroxy Acid from Xylose)
[0108] The conversion of xylose into substituted .alpha.-hydroxy
acids is carried out by anaerobic fermentation attributable to a
microorganism. Incidentally, the production of hydroxy acids by
microorganisms is disclosed in Japanese Patent Applications
Laid-open No. 5-336981, No. 7-327692 and No. 2000-300284. There,
however, is no specific disclosure as to any microorganisms capable
of producing substituted .alpha.-hydroxy acids from xylose.
[0109] As the microorganism, there are only few microorganisms
isolated and identified as strains capable of producing the
substituted .alpha.-hydroxy acid from glucose, and also these can
only be produced in a low efficiency. Accordingly, we have made
extensive screening on new strains. Here, for the reasons of
experiment efficiency and so forth, not the direct screening of
strains capable of converting the xylose into the substituted
.alpha.-hydroxy acid, but, like that made in the first embodiment,
screening has been first made on strains capable of converting
glucose into the substituted .alpha.-hydroxy acid, and then, from
among the strains obtained, screening has further been made on
strains capable of converting the xylose into the substituted
.alpha.-hydroxy acid.
[0110] For example, the 2-hydroxyisocaproic acid has been picked up
as the substituted .alpha.-hydroxy acid, and, using a VL culture
medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l of meat
extract, 5 g/l of NaCl and 2 g/l of cysteine hydrochloride) to
which 5 g/l of glucose and 5 g/l of calcium carbonate have been
added, and under anaerobic conditions of 30.degree. C., screening
has been made on strains having the ability to produce the
2-hydroxyisocaproic acid.
[0111] Then, on the strains thus obtained, the ability to produce
substituted .alpha.-hydroxy acids from xylose has been studied.
[0112] As the result, we have succeeded in obtaining the
Clostridium beijerinckii strain HICA432 as a strain capable of
producing 2-hydroxyisocaproic acid from xylose, which is a
bacterium of the genus Clostridium such as Clostridium
beijerinckii.
[0113] On the Clostridium beijerinckii strain HICA432, FERMP-18373,
thus obtained, products formed from xylose have further been
analyzed to find that, in addition to the 2-hydroxyisocaproic acid
as the substituted .alpha.-hydroxy acid represented by
HO--CHR--COOH (R is an isobutyl group), at least
.beta.-phenyllactic acid (R is a benzyl group) has been produced.
Hence, polyester can be produced from at least one of these
substituted .alpha.-hydroxy acids.
[0114] Thus, when the xylose is used as a single carbon source, as
being different from the case in which the glucose or starch is
used as the carbon source as described in the first and second
embodiments, the strain HICA432 does not substantially produce any
lactic acid.
[0115] Hence, when the substituted .alpha.-hydroxy acids produced
from xylose by the aid of the strain HICA432 are used, the
polyester obtained has at lest one of the repeating units
represented by the above Formulas (II) and (III).
[0116] A mixture of the 2-hydroxyisocaproic acid and
.beta.-phenyllactic acid produced from xylose may optionally be
purified to obtain a product containing substantially only the
.beta.-phenyllactic acid and a product containing substantially
only the 2-hydroxyisocaproic acid. The structures, physical
properties and so forth of the purified products thus obtained are
the same of those of the purified products obtained from glucose as
described in the first embodiment.
[0117] The 2-hydroxyisocaproic acid and .beta.-phenyllactic acid
may also individually be purified, and the purified products
obtained may be mixed in stated quantities to produce a polyester.
In this case, a wide range of physical properties of the polyester
can be materialized.
[0118] The fermentation for converting the xylose into the
substituted .alpha.-hydroxy acid is carried out by adding the
strain to a culture fluid containing the xylose as a chief carbon
source and also nitrogen, phosphorus, mineral(s), vitamin(s) and so
force added thereto as nutrients, and maintaining it under
anaerobic conditions.
[0119] The above strain is an absolutely anaerobic bacterium which
dies out in the presence of oxygen, and hence the anaerobic
conditions must strictly be set up. After the culture medium has
been injected, the gaseous-phase portion in a culturing container
hermetically stoppered with a butyl rubber stopper or the like not
transmitting any gases is displaced with nitrogen, carbon dioxide,
hydrogen or the like. Any oxygen in the culture medium must also be
removed using a reducing agent such as cysteine, sodium
thioglycolate or sodium sulfide or by heat treatment or exposure to
nitrogen.
[0120] The concentration of xylose in the culture fluid may be set
in accordance with the type of the microorganism used. In order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity, the xylose may usually be in a concentration
of 0.1% by weight or more, and preferably 0.5% by weight or more.
On the other hand, in order to make any by-products less develop,
it may usually be in a concentration of 10% by weight or less, and
preferably 5% by weight or less.
[0121] Any auxiliary carbon sources are unnecessary, and the xylose
may be used as a single carbon source. As nitrogen sources, usable
are organic or inorganic nitrogen sources such as urea, ammonia,
ammonium sulfate and ammonium nitrate, and natural nitrogen sources
such as corn steep liquor, peptone, meat extract and yeast extract.
As inorganic salts, usable are potassium phosphate, sodium
phosphate, magnesium sulfate, manganese sulfate, ferrous sulfate,
potassium chloride and sodium chloride.
[0122] Fermentation temperature may usually be set at 15.degree. C.
or above, and preferably 20.degree. C. or above, in order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity. On the other hand, in order to make any
by-products less develop and prevent the strain from dying out, it
may usually be set at 37.degree. C. or below, and preferably
35.degree. C. or below.
[0123] The culture fluid may also usually have a pH of
approximately from 5 to 8 as suitable temperature, which may
appropriately be set in accordance with the nature of the
microorganism.
[0124] Further with regard to fermentation time, which depends on
the type of the microorganism, in the case of the strain HICA432
the fermentation can be completed in three days to a week, or,
under selected conditions for pre-fermentation, in a day to three
days.
[0125] As described above, when the xylose is used as a single
carbon source, the strain HICA432 does not substantially produce
any lactic acid. Hence, this is advantageous when at least one of
the .beta.-phenyllactic acid and the 2-hydroxyisocaproic acid is
chiefly needed.
[0126] 4. Fourth Embodiment
[0127] The process of the fourth embodiment comprises the step of
hydrolyzing a material containing hemicellulose and cellulose, to
obtain xylose and glucose, and the step of fermenting the xylose
and glucose with a microorganism to obtain at least one substituted
.alpha.-hydroxy acid represented by the formula: HO--CHR--COOH
(wherein R represents a hydrocarbon group having 1 to 10 carbon
atoms).
[0128] These steps are described below.
[0129] (Xylose and Glucose from Hemicellulose and Cellulose)
[0130] As materials containing the raw materials hemicellulose and
cellulose, any commercially available hemicellulose and cellulose
may be used as a matter of course, and any waste hemicellulose and
waste cellulose obtained by appropriately treating waste paper,
woods such as waste wood as well as pulp waste liquor may also be
used. Thus, the establishment of a method of synthesizing polyester
from hemicellulose and cellulose can make a new route for the
recycling of waste hemicellulose and waste cellulose. In this
regard, the polyester production process of the present invention
is at the same time a useful method of recycling hemicellulose and
cellulose.
[0131] The conversion of hemicellulose and cellulose into xylose
and glucose, respectively, may be made by, e.g., a method of
decomposing the hemicellulose and cellulose with enzymes such as
xylanase and cellulanase, a method of decomposing them with an acid
such as sulfuric acid or hydrochloric acid, or a method of
decomposing them with supercritical water, whereby the
hemicellulose and cellulose can simultaneously be decomposed.
[0132] (Substituted .alpha.-Hydroxy Acid from Xylose and
Glucose)
[0133] The conversion of xylose and glucose into substituted
.alpha.-hydroxy acids is carried out by anaerobic fermentation
attributable to a microorganism. Incidentally, the production of
hydroxy acids by microorganisms is disclosed in Japanese Patent
Applications Laid-open No. 5-336981, No. 7-327692 and No.
2000-300284. There, however, is no specific disclosure as to any
microorganisms capable of producing substituted .alpha.-hydroxy
acids from xylose and glucose.
[0134] As the microorganism of the present embodiment, the same one
as that in the third embodiment is used. More specifically, not the
direct screening of strains capable of converting the xylose and
glucose into the substituted .alpha.-hydroxy acid, but, as
described in the first embodiment, screening has been first made on
strains capable of converting glucose into the substituted
.alpha.-hydroxy acid, and then, from among the strains obtained,
screening has further been made on strains capable of converting
also the xylose into the substituted .alpha.-hydroxy acid.
[0135] Then, on the strains thus obtained, the ability to produce
substituted .alpha.-hydroxy acids also from xylose has been
studied.
[0136] As the result, we have succeeded in obtaining the
Clostridium beijerinckii strain HICA432 as a strain capable of
producing 2-hydroxyisocaproic acid from xylose and glucose, which
is a bacterium of the genus Clostridium such as Clostridium
beijerinckii.
[0137] On the Clostridium beijerinckii strain HICA432, FERMP-18373,
thus obtained, products formed from xylose and glucose have further
been analyzed to find that, in addition to the 2-hydroxyisocaproic
acid as the substituted .alpha.-hydroxy acid represented by
HO--CHR--COOH (R is an isobutyl group), at least lactic acid (R is
a methyl group) and .beta.-phenyllactic acid (R is a benzyl group)
have been produced. Hence, polyester can be produced from at least
one of these substituted .alpha.-hydroxy acids.
[0138] Stated specifically, when the substituted .alpha.-hydroxy
acids produced from xylose and glucose by the aid of the strain
HICA432 are used, the polyester obtained has at lest one of the
repeating units represented by the above Formulas (I) to (III).
[0139] The substituted .alpha.-hydroxy acids produced from xylose
and glucose by the aid of the strain HICA432 may optionally be
purified in the same manner as in Example as in the foregoing
embodiments. The structures, physical properties and so forth of
the purified products thus obtained are also the same as those of
the purified products obtained in the first embodiment.
[0140] The fermentation for converting the xylose and glucose into
the substituted .alpha.-hydroxy acid is carried out by adding the
strain to a culture fluid containing the xylose and glucose as
chief carbon sources and also nitrogen, phosphorus, mineral(s),
vitamin(s) and so force added thereto as nutrients, and maintaining
it under anaerobic conditions.
[0141] The above strain is an absolutely anaerobic bacterium which
dies out in the presence of oxygen, and hence the anaerobic
conditions must strictly be set up. After the culture medium has
been injected, the gaseous-phase portion in a culturing container
hermetically stoppered with a butyl rubber stopper or the like not
transmitting any gases is displaced with nitrogen, carbon dioxide,
hydrogen or the like. Any oxygen in the culture medium must also be
removed using a reducing agent such as cysteine, sodium
thioglycolate or sodium sulfide or by heat treatment or exposure to
nitrogen.
[0142] The concentration of xylose and glucose in the culture fluid
may be set in accordance with the type of the microorganism used.
In order to materialize the production of substituted
.alpha.-hydroxy acids in a sufficient quantity, any one of the
xylose and glucose or the total of the xylose and glucose may
usually be in a concentration of 0.1% by weight or more, and
preferably 0.5% by weight or more. On the other hand, in order to
make any by-products less develop, it may usually be in a
concentration of 10% by weight or less, and preferably 5% by weight
or less.
[0143] Any auxiliary carbon sources are unnecessary, and only the
xylose and glucose may be used as carbon sources. As nitrogen
sources, usable are organic or inorganic nitrogen sources such as
urea, ammonia, ammonium sulfate and ammonium nitrate, and natural
nitrogen sources such as corn steep liquor, peptone, meat extract
and yeast extract. As inorganic salts, usable are potassium
phosphate, sodium phosphate, magnesium sulfate, manganese sulfate,
ferrous sulfate, potassium chloride and sodium chloride.
[0144] Fermentation temperature may usually be set at 15.degree. C.
or above, and preferably 20.degree. C. or above, in order to
materialize the production of substituted .alpha.-hydroxy acids in
a sufficient quantity. On the other hand, in order to make any
by-products less develop and prevent the strain from dying out, it
may usually be set at 37.degree. C. or below, and preferably
35.degree. C. or below.
[0145] The culture fluid may also usually have a pH of
approximately from 5 to 8 as suitable temperature, which may
appropriately be set in accordance with the nature of the
microorganism.
[0146] Further with regard to fermentation time, which depends on
the type of the microorganism, in the case of the strain HICA432
the fermentation can be completed in three days to a week, or,
under selected conditions for pre-fermentation, in a day to three
days.
[0147] B. The Step of Obtaining Cyclic Dimer Lactide from
Substituted .alpha.-Hydroxy Acid:
[0148] The polyester may directly be produced from the substituted
.alpha.-hydroxy acid obtained through the steps described in any of
the first to fourth embodiments. However, prior to the step of
polymerization, the substituted .alpha.-hydroxy acid may be
converted into a derivative having a high polymerization
activity.
[0149] For example, the substituted .alpha.-hydroxy acid may be
subjected to dehydration by two molecules to effect cyclic
diesterification to form a cyclic dimer lactide as a derivative of
the substituted .alpha.-hydroxy acid, and thereafter this cyclic
dimer lactide may be subjected to ring-opening polymerization to
produce the polyester. The ring-opening polymerization commonly
proceeds at a high polymerization rate, and a polyester with a high
degree of polymerization can be produced.
[0150] As a method of dehydrating the substituted .alpha.-hydroxy
acid by two molecules to effect cyclic diesterification, using,
e.g., a reactor having a Dean Stark trap, the substituted
.alpha.-hydroxy acid and a condensation catalyst such as p-toluene
sulfonate may be subjected to azeotropic dehydration in toluene in
an atmosphere of nitrogen for 30 hours, and the water having
gathered in the Dean Stark trap may appropriately be removed to
obtain the cyclic dimer lactide in a high yield.
[0151] Where lactic acid is subjected to dehydration by two
molecules to effect cyclic diesterification under the above
conditions, the cyclic dimer lactide obtained is a compound
represented by the following Formula (I'). 2
[0152] Where .beta.-phenyllactic acid is subjected to dehydration
by two molecules to effect cyclic diesterification under the above
conditions, the cyclic dimer lactide obtained is a compound
represented by the following Formula (II'). 3
[0153] Where 2-hydroxyisocaproic acid is subjected to dehydration
by two molecules to effect cyclic diesterification under the above
conditions, the cyclic diner lactide obtained is a compound
represented by the following Formula (III'). 4
[0154] C. The Step of Obtaining Polyester from Substituted
.alpha.-Hydroxy Acid:
[0155] The desired polyester may be obtained by refluxing the
substituted .alpha.-hydroxy acid and a polymerization catalyst in
an organic solvent, and removing outside the reaction system the
water formed in the course of polymerization to make condensation
polymerization proceed.
[0156] (a) Polymerization Catalyst:
[0157] In effecting the condensation polymerization of the
substituted .alpha.-hydroxy acid, usable as the polymerization
catalyst are, e.g., metal powders such as tin powder and zinc
powder; metal oxides such as tin oxide, zinc oxide, magnesium
oxide, titanium oxide and aluminum oxide; and metal halides such as
tin dichloride, tin tetrachloride, tin dibromide, tin tetrabromide,
zinc chloride, magnesium chloride and aluminum chloride; as well as
tetraphenyltin, tin octylate and p-toluene sulfonate.
[0158] The polymerization catalyst may be used in an amount of from
0.001% by weight to 10% by weight, and preferably from 0.01% by
weight to 5% by weight, based on the weight of the substituted
.alpha.-hydroxy acid.
[0159] (b) Polymerization Solvent:
[0160] In effecting the condensation polymerization of the
substituted .alpha.-hydroxy acid, usable as the polymerization
solvent are, e.g., solvents such as toluene, xylene, mesitylene,
1,2,3,5-tetramethylbenzene, chlorobenzene, 1,2-dichlorobenzene,
1,3-dichlorobenzene, bromobenzene, 1,2-dibromobenzene,
1,3-dibromobenzene, iodobenzene, 1,2-diiodobenzene, diphenyl ether
and dibenzyl ether. Any of these may be used in the form of a
mixture.
[0161] The polymerization catalyst may preferably be used in such
an amount that the substituted .alpha.-hydroxy acid come to be in a
concentration of from 5% by weight to 50% by weight.
[0162] (c) Polymerization Conditions:
[0163] In effecting the condensation polymerization of the
substituted .alpha.-hydroxy acid, the polymerization may be carried
out at a temperature of from 50.degree. C. to 200.degree. C., and
preferably from 110.degree. C. to 180.degree. C., taking account of
the rate of formation of a polymer and the rate of thermal
decomposition of the polymer formed. The condensation
polymerization reaction is usually carried out at the temperature
at which the organic solvent used under normal pressure comes to
evaporate. Where an organic solvent having a high boiling point is
used, the polymerization may also be carried out under reduced
pressure.
[0164] In effecting the condensation polymerization of the
substituted .alpha.-hydroxy acid, it may preferably be carried out
in an atmosphere of an inert gas. It may also be carried out
displacing the inside of a reactor with an inert gas, or bubbling
the reaction mixture with an inert gas. Also, the water formed in
the course of polymerization is appropriately removed from the
reactor.
[0165] The polyester obtained by polymerization may be made to have
various molecular weights by changing polymerization conditions
such as the type of the polymerization solvent, the type and amount
of the polymerization catalyst, the polymerization temperature and
the polymerization time. It may preferably have a weight-average
molecular weight of from 5,000 to 1,000,000 in terms of
polystyrene.
[0166] The polyester thus obtained may be mixed with a
heat-resistant stabilizer, a weathering stabilizer, an antioxidant,
an antistatic agent, a flame retardant, a lubricant, a dye, a
pigment, an ultraviolet absorbent, a cross-linking agent and so
forth as long as the object of the present invention is not
damaged. There are no particular limitations on the proportion in
which these are mixed, which may appropriately be determined.
[0167] Where the polyester is produced by carrying out the
condensation polymerization in an organic solvent at a temperature
lower than 200.degree. C., it can be kept from being colored or
causing any impurities due to thermal decomposition. Hence, when it
is used for purposes such as adhesives and coating meterials, it
can be dyed in any desired color, and there is an advantage on
external appearance.
[0168] The polyester obtained as described above has good melt
molderability, and a polyester having a weight-average molecular
weight more than 50,000 has sufficient mechanical strength.
Accordingly, it is utilizable for many purposes. For example, it
may be used for packaging films, bottles, cups, trays, spoons,
knives, forks, trash or garbage bags and so forth.
[0169] The substituted .alpha.-hydroxy acid is also an optical
isomer (chiral), and the polyester obtained by subjecting the
substituted .alpha.-hydroxy acid directly to dehydration
condensation polymerization also retains a chiral structure.
Accordingly, the polyester may also be used as an optical material.
Its uses are by no means limited to these.
[0170] D. The Step of Obtaining Polyester from Cyclic Dimer
Lactide:
[0171] The polyester production process described in the previous
paragraph is the process of obtaining a polyester by polymerization
of the substituted .alpha.-hydroxy acid. The desired polyester may
also be obtained by adding a polymerization catalyst to the cyclic
dimer lactide to effect ring-opening polymerization in an
atmosphere of an inert gas.
[0172] (a) Polymerization Catalyst:
[0173] In effecting the ring-opening polymerization of the cyclic
dimer lactide, usable as the polymerization catalyst are, e.g.,
metal powders such as tin powder and zinc powder; metal oxides such
as tin oxide, zinc oxide, magnesium oxide, titanium oxide and
aluminum oxide; and metal halides such as tin dichloride, tin
tetrachloride, tin dibromide, tin tetrabromide, zinc chloride,
magnesium chloride and aluminum chloride; as well as tetraphenyltin
and tin octylate. Of these, tin and tin compounds have a superior
catalytic activity, and these are particularly preferred.
[0174] The polymerization catalyst may be used in an amount of from
0.001% by weight to 10% by weight, and preferably from 0.01% by
weight to 5% by weight, based on the weight of the cyclic dimer
lactide.
[0175] (b) Polymerization Conditions:
[0176] In effecting the ring-opening polymerization of the cyclic
dimer lactide, the polymerization may be carried out at a
temperature of from 100.degree. C. to 200.degree. C., and
preferably from 120.degree. C. to 180.degree. C., taking account of
the rate of formation of a polymer and the rate of thermal
decomposition of the polymer formed.
[0177] In effecting the ring-opening polymerization of the cyclic
dimer lactide, it may preferably be carried out in an atmosphere of
an inert gas. As the inert gas, usable are, e.g., nitrogen gas and
argon gas.
[0178] The polyester obtained by polymerization may be made to have
various molecular weights by changing polymerization conditions
such as the type and amount of the polymerization catalyst, the
polymerization temperature and the polymerization time. It may
preferably have a weight-average molecular weight of from 5,000 to
1,000,000 in terms of polystyrene.
[0179] The polyester thus obtained may be mixed with a
heat-resistant stabilizer, a weathering stabilizer, an antioxidant,
an antistatic agent, a flame retardant, a lubricant, a dye, a
pigment, an ultraviolet absorbent, a cross-linking agent and so
forth as long as the object of the present invention is not
damaged. There are no particular limitations on the proportion in
which these are mixed, which may appropriately be determined.
[0180] Where the polyester is produced by carrying out the
ring-opening polymerization at a temperature lower than 200.degree.
C., it can be kept from being colored or causing any impurities due
to thermal decomposition. Hence, when it is used for purposes such
as adhesives and coating materials, it can be dyed in any desired
color, and there is an advantage on external appearance.
[0181] The polyester obtained as described above has good melt
molderability, and a polyester having a weight-average molecular
weight more than 50,000 has sufficient mechanical strength.
Accordingly, it is utilizable for many purposes. For example, it
may be used for packaging films, bottles, cups, trays, spoons,
knives, forks, trash or garbage bags and so forth.
[0182] The present invention is described below in greater detain
by giving Examples. The present invention is by no means limited to
these Examples. Also, unless particularly noted, commercially
available high-purity products are used as reagents and so
forth.
[0183] A method for the screening of the microorganisms used in the
step of obtaining the substituted .alpha.-hydroxy acid by the
fermentation of glucose with microorganisms as described in the
first embodiment is described first.
[0184] (Screening of Microorganisms Capable of Producing
2-Hydroxyisocaproic Acid)
[0185] Reducing soil positioned at a layer lower by few centimeters
from the soil surface layer of a swamp area standing wet, films of
microorganisms at drain ditch surfaces, and scum floating on the
surface of still water were sampled, and these were pre-cultured in
a VL culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2
g/l of meat extract, 5 g/l of NaCl and 2 g/l of cysteine
hydrochloride) to which 5 g/l of glucose and 5 g/l of calcium
carbonate had been added.
[0186] The culture medium was injected into a vial bottle in order
to provide anaerobic conditions. Thereafter, its gaseous-phase
portion was displaced with nitrogen gas, and the bottle was
hermetically stoppered, followed by treatment in an autoclave
(121.degree. C., 98 kPa pressure, 10 minutes), which was then
opened when the sample was added. After the sample was added, the
gaseous-phase portion of the vial bottle was again displaced with
nitrogen gas, and the bottle was hermetically stoppered with a
butyl rubber stopper. Thereafter, static culture was performed but
with stirring occasionally, at 30.degree. C. for two weeks under
anaerobic conditions, and then the pre-cultured fluid was added to
the above culture medium kept under anaerobic conditions by the
same method as the above, in an amount of 1% by volume based on the
volume of the culture medium.
[0187] Thereafter, static culture was performed but with stirring
occasionally, at 30.degree. C. for a week, and then the
2-hydroxyisocaproic acid produced in the culture fluid was
subjected to methylation. The resultant 2-hydroxyisocaproic acid
methyl ester was evaluated by GC-MS (gas chromatograph-gas
spectroscopy). Next, the culture fluid in which the formation of
2-hydroxyisocaproic acid was recognized was sterilized, which was
then diluted over several stages, with 2 g/l of an aqueous systeine
hydrochloride solution whose pH was adjusted to 7.0, and was
cultured for each stage of dilution by the roll tube method. As the
culture medium, a culture medium was used which was prepared by
adding 2% by weight of agar to the above culture medium.
[0188] Thereafter, culture was performed at 30.degree. C. for 1
week, and the colony having developed was suspended in the above
culture medium in a glove box filled with nitrogen gas; the culture
medium being kept under anaerobic conditions by the same method as
the above. Thereafter, static culture was performed but with
stirring occasionally, at 30.degree. C. for a week, and then the
2-hydroxyisocaproic acid produced in the culture fluid was
subjected to methylation. The resultant 2-hydroxyisocaproic acid
methyl ester was evaluated by GC-MS. The culture fluid in which the
2-hydroxyisocaproic acid was produced in a large quantity was
cultured by the roll tube method in the same manner as the above.
Then, the colony formed was separated to isolate the strain capable
of producing 2-hydroxyisocaproic acid. The strain thus isolated was
identified to be Clostridium beijerinckii, and was named the strain
HICA432 (FERMP-18373).
[0189] The strain HICA432 has been ascertained to be capable of
producing not only the 2-hydroxyisocaproic acid but also lactic
acid and phenyllactic acid. Accordingly, in the following, the
strain HICA432 is also called a 2-hydroxyisocaproic acid productive
strain, a lactic acid productive strain, and a phenyllactic acid
productive strain.
[0190] The following Examples 1 to 48 concern the polyester
production process comprising the step of obtaining the substituted
.alpha.-hydroxy acid by the fermentation of glucose with a
microorganism, described in the first embodiment. As the
microorganism, the 2-hydroxyisocaproic acid productive strain,
strain HICA432, was used in all Examples.
EXAMPLE 1
[0191] 370 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 11,050
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 37 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
11,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 735 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 220 parts by
weight of glucose.
[0192] The .sup.13C-NMR (100 MHz; internal standard reference
material: TMS (tetramethylsilane), DMSO(dimethyl
sulfoxide)-d.sub.6) of the glucose obtained was measured with
FT-NMR DPX400, manufactured by Bruker Co. Its chemical shifts
.delta. (ppm) were as follows:
[0193] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0194] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0195] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0196] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 3 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure.
Thereafter, the solid content having remained was heated under
reduced pressure. The gas having sublimated was cooled and the
solid matter having precipitated was collected to obtain 10 parts
by weight of 2-hydroxyisocaproic acid.
[0197] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
2-hydroxyisocaproic acid thus obtained was measured to obtain the
results as follows: (.delta./ppm); 180.25, 68.95, 43.16, 24.45,
23.20, 21.42. From these results of measurement, it was ascertained
that the desired 2-hydroxyisocaproic acid was obtained.
[0198] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
2-hydroxyisocaproic acid obtained was in the L-form.
[0199] Using a reactor having a Dean Stark trap, 10 parts by weight
of the 2-hydroxyisocaproic acid and 0.02 part by weight of tin
dichloride were put into it and 100 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 40 hours,
and the aliphatic polyester obtained had a weight-average molecular
weight of 90,000.
[0200] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was also
measured to obtain the results (.delta./ppm) of 169.78, 71.38,
39.33, 24.53, 23.00, 21.43. Thus, it was ascertained that the
desired aliphatic polyester was synthesized.
[0201] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 90,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0202] Thickness: 38 to 39 .mu.m
[0203] Tensile strength: 48 MPa (yield), 48 MPa (breaking)
[0204] Elongation: 5%
EXAMPLE 2
[0205] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 1, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 10 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of zinc
chloride were put into it and 100 parts by weight of
1,3-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 45 hours, and the aliphatic polyester
obtained had a weight-average molecular weight of 140,000.
[0206] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 140,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0207] Thickness: 39 to 40 .mu.m
[0208] Tensile strength: 57 MPa (yield), 56 MPa (breaking)
[0209] Elongation: 9%
Example 3
[0210] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
380 parts by weight of the same was introduced into 11,300 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 40 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 11,200
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 750 parts by weight of
methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 210 parts by weight of glucose.
210 parts by weight of this glucose was mixed with 11,600 parts by
weight of a culture medium (10 g/l of peptone, 5 g/l of yeast
extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of cysteine
hydrochloride and 5 g/l of calcium carbonate), and the mixture
formed was injected into a pressure bottle. After the gaseous-phase
portion in the bottle was displaced with nitrogen gas, the bottle
was hermetically stoppered with a butyl rubber stopper, which was
then treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 116 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid productive strain HICA432 isolated in the
manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 3 days. Thereafter,
the procedure in Example 1 was repeated to collect 9 parts by
weight of 2-hydroxyisocaproic acid.
[0211] Its .sup.13C-NMR was measured to find that the same spectrum
as that in Example 1 was obtained, and it was ascertained that the
desired 2-hydroxyisocaproic acid was obtained.
[0212] Using the reactor having a Dean Stark trap, 9 parts by
weight of the 2-hydroxyisocaproic acid and 0.018 part by weight of
tin octylate were put into it and 90 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 40 hours,
and the aliphatic polyester obtained had a weight-average molecular
weight of 50,000.
[0213] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 1 was obtained, and it was ascertained
that the desired aliphatic polyester was obtained.
[0214] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0215] Thickness: 38 to 39 .mu.m
[0216] Tensile strength: 20 MPa (yield), 20 MPa (breaking)
[0217] Elongation: 3%
EXAMPLE 4
[0218] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 3, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 9 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of tin powder
were put into it and 100 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 190,000.
[0219] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0220] Thickness: 39 to 40 .mu.m
[0221] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0222] Elongation: 13%
EXAMPLE 5
[0223] 370 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 11,050
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 37 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
11,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 735 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 220 parts by
weight of glucose.
[0224] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0225] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0226] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0227] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0228] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 3 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure.
Thereafter, the solid content having remained was heated under
reduced pressure. The gas having sublimated was cooled and the
solid matter having precipitated was collected to obtain 10 parts
by weight of 2-hydroxyisocaproic acid.
[0229] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
2-hydroxyisocaproic acid was measured to obtain the results
(.delta./ppm) of 180.25, 68.95, 43.16, 24.45, 23.20, 21.42. Thus,
it was ascertained that the desired 2-hydroxyisocaproic acid was
obtained.
[0230] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid and 0.2 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 8.2 parts by weight
of a cyclic dimer lactide.
[0231] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the cyclic
dimer lactide obtained was measured to obtain the results
(.delta./ppm) of 167.33, 74.14, 38.87, 23.89, 23.03, 21.33. Thus,
it was ascertained that the desired cyclic dimer lactide was
obtained. 8.2 parts by weight of the cyclic dimer lactide and 0.01
part by weight of tin chloride were heated at 150.degree. C. for 12
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 180,000.
[0232] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
aliphatic polyester was measured to obtain the results
(.delta./ppm) of 169.78, 71.38, 39.33, 24.53, 23.00, 21.43. Thus,
it was ascertained that the desired aliphatic polyester was
synthesized.
[0233] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0234] Thickness: 38 to 39 .mu.m
[0235] Tensile strength: 68 MPa (yield), 68 MPa (breaking)
[0236] Elongation: 13%
EXAMPLE 6
[0237] Using a cyclic dimer lactide obtained through the same
procedure as in Example 5, an aliphatic polyester was synthesized.
That is, 8.2 parts by weight of the cyclic dimer lactide and 0.01
part by weight of zinc chloride were heated at 120.degree. C. for 5
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 50,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 5 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0238] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0239] Thickness: 39 to 40 .mu.m
[0240] Tensile strength: 29 MPa (yield), 29 MPa (breaking)
[0241] Elongation: 4%
EXAMPLE 7
[0242] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
380 parts by weight of the same was introduced into 11,300 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 40 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 11,200
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 750 parts by weight of
methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 210 parts by weight of
glucose.
[0243] 210 parts by weight of this glucose was mixed with 11,600
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 116 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 3 days. Thereafter, the procedure in Example 5 was repeated to
collect 9 parts by weight of 2-hydroxyisocaproic acid.
[0244] Its .sup.13C-NMR was measured to find that the same spectrum
as that in Example 5 was obtained, and it was ascertained that the
desired 2-hydroxyisocaproic acid was obtained. Then, 9 parts by
weight of the 2-hydroxyisocaproic acid obtained was treated through
the same procedure as in Example 5 to obtain 7.4 parts by weight of
a cyclic dimer lactide. 7.4 parts by weight of the cyclic dimer
lactide and 0.008 part by weight of tin octylate were heated at
180.degree. C. for 30 hours in an atmosphere of nitrogen to effect
ring-opening polymerization. The aliphatic polyester thus obtained
had a weight-average molecular weight of 680,000. Its .sup.13C-NMR
was measured to find that the same spectrum as that in Example 5
was obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0245] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 680,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0246] Thickness: 38 to 39 .mu.m
[0247] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0248] Elongation: 30%
EXAMPLE 8
[0249] Using a cyclic dimer lactide obtained through the same
procedure as in Example 7, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic diner lactide and 0.007
part by weight of tin powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 390,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 5 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0250] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 390,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0251] Thickness: 39 to 40 .mu.m
[0252] Tensile strength: 88 MPa (yield), 87 MPa (breaking)
[0253] Elongation: 22%
EXAMPLE 9
[0254] 370 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 11,050
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 37 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
11,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 735 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 220 parts by
weight of glucose.
[0255] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0256] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0257] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0258] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0259] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3
days.
[0260] Thereafter, the culture fluid was filtered, and the water
and volatile components of the filtrate obtained were evaporated
off under normal-temperature reduced pressure, followed by
purification to obtain 10 parts by weight of phenyllactic acid. The
.sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the phenyllactic acid
thus obtained was measured to obtain the results (.delta./ppm) of
177.92, 137.63, 130.30, 129.46, 127.82, 72.05, 40.38, and it was
ascertained that the desired phenyllactic acid was obtained.
[0261] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
phenyllactic acid obtained was in the L-form.
[0262] Using the reactor having a Dean Stark trap, 10 parts by
weight of the phenyllactic acid and 0.018 part by weight of tin
dichloride were put into it and 100 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 44 hours,
and the aromatic polyester obtained had a weight-average molecular
weight of 180,000.
[0263] The aromatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0264] Thickness: 38 to 39 .mu.m
[0265] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0266] Elongation: 12%
EXAMPLE 10
[0267] Using phenyllactic acid obtained through the same procedure
as in Example 9, an aromatic polyester was synthesized. Using the
reactor having a Dean Stark trap, 10 parts by weight of the
phenyllactic acid and 0.02 part by weight of zinc chloride were put
into it and 100 parts by weight of 1,3-dichlorobenzene was added
thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 16 hours, and
the aromatic polyester obtained had a weight-average molecular
weight of 30,000.
[0268] The aromatic polyester thus obtained, having a
weight-average molecular weight of 30,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0269] Thickness: 39 to 40 .mu.m
[0270] Tensile strength: 20 MPa (yield), 19 MPa (breaking)
[0271] Elongation: 2%
EXAMPLE 11
[0272] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
380 parts by weight of the same was introduced into 11,300 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 40 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 11,200
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 750 parts by weight of
methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 210 parts by weight of
glucose.
[0273] 210 parts by weight of this glucose was mixed with 11,600
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 116 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the procedure in Example 1 was repeated to collect 9
parts by weight of phenyllactic acid.
[0274] Its .sup.13C-NMR was measured to find that the same spectrum
as that in Example 9 was obtained, and it was ascertained that the
desired phenyllactic acid was obtained.
[0275] Using the reactor having a Dean Stark trap, 9 parts by
weight of the phenyllactic acid and 0.016 part by weight of tin
oxide were put into it and 90 parts by weight of mesitylene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 40 hours, and
the aromatic polyester obtained had a weight-average molecular
weight of 90,000.
[0276] The aromatic polyester thus obtained, having a
weight-average molecular weight of 90,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0277] Thickness: 38 to 39 .mu.m
[0278] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0279] Elongation: 5%
EXAMPLE 12
[0280] Using phenyllactic acid obtained through the same procedure
as in Example 11, an aromatic polyester was synthesized. Using the
reactor having a Dean Stark trap, 9 parts by weight of the
phenyllactic acid and 0.015 part by weight of tin powder were put
into it and 100 parts by weight of diphenyl ether was added thereto
to effect azeotropic dehydration at 130.degree. C./12 mmHg, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 48 hours, and the aromatic
polyester obtained had a weight-average molecular weight of
250,000.
[0281] The aromatic polyester thus obtained, having a
weight-average molecular weight of 250,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0282] Thickness: 39 to 40 .mu.m
[0283] Tensile strength: 82 MPa (yield), 81 MPa (breaking)
[0284] Elongation: 18%
EXAMPLE 13
[0285] 370 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 11,050
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 37 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
11,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 735 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 220 parts by
weight of glucose.
[0286] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0287] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0288] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0289] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0290] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by purification
to obtain 10 parts by weight of phenyllactic acid.
[0291] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
phenyllactic acid was measured to obtain the results (.delta./ppm)
of 177.92, 137.63, 130.30, 129.46, 127.82, 72.05, 40.38, and it was
ascertained that the desired phenyllactic acid was obtained.
[0292] Using the reactor having a Dean Stark trap, 10 parts by
weight of the phenyllactic acid and 0.2 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 8.7 parts by weight
of a cyclic dimer lactide.
[0293] 8.7 parts by weight of the cyclic dimer lactide and 0.01
part by weight of tin chloride were heated at 160.degree. C. for 10
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 190,000.
[0294] The aromatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0295] Thickness: 39 to 40 .mu.m
[0296] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0297] Elongation: 12%
EXAMPLE 14
[0298] Using a cyclic dimer lactide obtained through the same
procedure as in Example 13, an aromatic polyester was synthesized.
That is, 8.7 parts by weight of the cyclic dimer lactide and 0.01
part by weight of zinc chloride were heated at 120.degree. C. for 5
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 50,000.
[0299] The aromatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0300] Thickness: 40 to 41 .mu.m
[0301] Tensile strength: 31 MPa (yield), 30 MPa (breaking)
[0302] Elongation: 3%
EXAMPLE 15
[0303] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
380 parts by weight of the same was introduced into 11,300 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 40 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 11,200
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 750 parts by weight of
methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 210 parts by weight of
glucose.
[0304] 210 parts by weight of this glucose was mixed with 11,600
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 116 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the procedure in Example 13 was repeated to collect 9
parts by weight of phenyllactic acid.
[0305] Its .sup.13C-NMR was measured to find that the same spectrum
as that in Example 13 was obtained, and it was ascertained that the
desired phenyllactic acid was obtained. 9 parts by weight of the
phenyllactic acid obtained was treated through the same procedure
as in Example 13 to obtain 7.8 parts by weight of a cyclic dimer
lactide.
[0306] 7.8 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin octylate were heated at 180.degree. C. for 33
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 700,000.
[0307] The aromatic polyester thus obtained, having a
weight-average molecular weight of 700,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0308] Thickness: 39 to 40 .mu.m
[0309] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0310] Elongation: 25%
EXAMPLE 16
[0311] Using a cyclic dimer lactide obtained through the same
procedure as in Example 15, an aromatic polyester was synthesized.
That is, 7.8 parts by weight of the cyclic dimer lactide and 0.006
part by weight of tin powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 380,000.
[0312] The aromatic polyester thus obtained, having a
weight-average molecular weight of 380,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0313] Thickness: 38 to 39 .mu.m
[0314] Tensile strength: 87 MPa (yield), 86 MPa (breaking)
[0315] Elongation: 16%
EXAMPLE 17
[0316] 340 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 10,250
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 34 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
10,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 670 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 200 parts by
weight of glucose.
[0317] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0318] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0319] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0320] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0321] 200 parts by weight of this glucose was mixed with 11,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/lactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 10 parts by weight of
2-hydroxyisocaproic acid and 12 parts by weight of lactic acid was
obtained.
[0322] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 tol.48 (m, 2H), 1.72 to 1.82 (m, lH), 3.94
(dd, 1H); lactic acid: 1.25 (d, J=6.8 Hz, 3H), 4.07 (q, J=6.8 Hz,
1H).
[0323] Its .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) was also
measured to obtain the results (.delta./ppm) as follows:
2-hydroxyisocaproic acid: 21.43, 23.12, 23.84, 42.84, 68.07,
176.23; lactic acid: 20.39, 65.82, 176.42.
[0324] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0325] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the lactic acid obtained was in the DL-form.
[0326] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid, 12 parts by weight of the
lactic acid and 0.044 part by weight of tin dichloride were put
into it and 220 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the aliphatic
polyester copolymer obtained had a weight-average molecular weight
of 170,000.
[0327] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was measured to
obtain the results (.delta./ppm) of 16.66, 21.43, 22.99, 24.55,
39.30, 68.97, 71.37, 169.51, 169.76. Thus, it was ascertained that
the desired aliphatic polyester copolymer was synthesized.
[0328] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 170,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0329] Thickness: 38 to 39 .mu.m
[0330] Tensile strength: 61 MPa (yield), 59 MPa (breaking)
[0331] Elongation: 14%
EXAMPLE 18
[0332] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 17, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the lactic acid and 0.04 part by weight of zinc powder
were put into it and 200 parts by weight of 1,3-dichlorobenzene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 38 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 100,000.
[0333] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 17 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0334] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 100,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0335] Thickness: 39 to 40 .mu.m
[0336] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0337] Elongation: 6%
EXAMPLE 19
[0338] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
500 parts by weight of the same was introduced into 15,050 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 50 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 15,000
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 1,000 parts by weight
of methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 280 parts by weight of
glucose.
[0339] 280 parts by weight of this glucose was mixed with 15,400
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 154 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/lactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 13 parts by weight of
2-hydroxyisocaproic acid and 16 parts by weight of lactic acid was
obtained.
[0340] Using the reactor having a Dean Stark trap, 13 parts by
weight of the 2-hydroxyisocaproic acid, 16 parts by weight of the
lactic acid and 0.058 part by weight of tin octilate were put into
it and 290 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 36 hours, and the aliphatic
polyester copolymer obtained had a weight-average molecular weight
of 60,000.
[0341] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 17 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0342] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 60,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0343] Thickness: 38 to 39 .mu.m
[0344] Tensile strength: 22 MPa (yield), 22 MPa (breaking)
[0345] Elongation: 3%
EXAMPLE 20
[0346] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 19, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 13 parts by weight of the 2-hydroxyisocaproic acid, 16 parts
by weight of the lactic acid and 0.052 part by weight of tin powder
were put into it and 320 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 290,000.
[0347] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 17 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0348] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 290,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0349] Thickness: 39 to 40 .mu.m
[0350] Tensile strength: 74 MPa (yield), 73 MPa (breaking)
[0351] Elongation: 23%
EXAMPLE 21
[0352] 200 parts by weight of glucose obtained through the same
procedure as in Example 17 was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with a mixed gas of 98% of nitrogen and 2% of
oxygen to bring the inside of the bottle into a slightly aerobic
condition, the bottle was hermetically stoppered with a butyl
rubber stopper, which was then treated in an autoclave (121.degree.
C., 98 kPa pressure, 10 minutes). Thereafter, the culture medium
treated was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/lactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 4 parts by weight of
2-hydroxyisocaproic acid and 18 parts by weight of lactic acid was
obtained.
[0353] Using the reactor having a Dean Stark trap, 4 parts by
weight of the 2-hydroxyisocaproic acid, 18 parts by weight of the
lactic acid and 0.04 part by weight of tin oxide were put into it
and 210 parts by weight of bromobenzene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 45 hours, and the aliphatic polyester
copolymer obtained had a weight-average molecular weight of
220,000.
[0354] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 17 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0355] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 220,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0356] Thickness: 37 to 38 .mu.m
[0357] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0358] Elongation: 18%
EXAMPLE 22
[0359] 280 parts by weight of glucose obtained through the same
procedure as in Example 19 was cultured in the same manner as in
Example Example 21. Thereafter, the culture fluid was filtered, and
the water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure, followed
by analysis by NMR. As the result, it was ascertained that a
mixture of 5 parts by weight of 2-hydroxyisocaproic acid and 16
parts by weight of lactic acid was obtained.
[0360] Using the reactor having a Dean Stark trap, 5 parts by
weight of the 2-hydroxyisocaproic acid, 16 parts by weight of the
lactic acid and 0.038 part by weight of p-toluenesulfonic acid were
put into it and 200 parts by weight of 1,2-dichlorobenzene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 32 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 40,000.
[0361] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 17 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0362] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 40,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0363] Thickness: 40 to 41 .mu.m
[0364] Tensile strength: 19 MPa (yield), 19 MPa (breaking)
[0365] Elongation: 2%
EXAMPLE 23
[0366] 340 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 10,250
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 34 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
10,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 670 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 200 parts by
weight of glucose.
[0367] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0368] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0369] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0370] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0371] 200 parts by weight of this glucose was mixed with 11,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/phenyllactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 10 parts by weight of
2-hydroxyisocaproic acid and 12 parts by weight of phenyllactic
acid was obtained.
[0372] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); phenyllactic acid: 2.82, 2.95, 4.16, 7.25.
[0373] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0374] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0375] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid, 12 parts by weight of the
phenyllactic acid and 0.044 part by weight of tin dichloride were
put into it and 220 parts by weight of mesitylene was added thereto
to effect azeotropic dehydration in an atmosphere of nitrogen, and
the water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the polyester
copolymer obtained had a weight-average molecular weight of
160,000.
[0376] The polyester copolymer thus obtained, having a
weight-average molecular weight of 160,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0377] Thickness: 37 to 38 .mu.m
[0378] Tensile strength: 60 MPa (yield), 60 MPa (breaking)
[0379] Elongation: 13%
EXAMPLE 24
[0380] Using 2-hydroxyisocaproic acid and phenyllactic acid
obtained through the same procedure as in Example 23, a polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the phenyllactic acid and 0.04 part by weight of zinc
powder were put into it and 200 parts by weight of
1,3-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 38 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 110,000.
[0381] The polyester copolymer thus obtained, having a
weight-average molecular weight of 110,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0382] Thickness: 39 to 40 .mu.m
[0383] Tensile strength: 50 MPa (yield), 49 MPa (breaking)
[0384] Elongation: 7%
EXAMPLE 25
[0385] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
500 parts by weight of the same was introduced into 15,050 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 50 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 15,000
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 1,000 parts by weight
of methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 280 parts by weight of
glucose.
[0386] 280 parts by weight of this glucose was mixed with 15,400
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 154 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/phenyllactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 13 parts by weight of
2-hydroxyisocaproic acid and 16 parts by weight of phenyllactic
acid was obtained.
[0387] Using the reactor having a Dean Stark trap, 13 parts by
weight of the 2-hydroxyisocaproic acid, 16 parts by weight of the
phenyllactic acid and 0.058 part by weight of tin octilate were put
into it and 290 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 36 hours, and the polyester
copolymer obtained had a weight-average molecular weight of
70,000.
[0388] The polyester copolymer thus obtained, having a
weight-average molecular weight of 70,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0389] Thickness: 40 to 41 .mu.m
[0390] Tensile strength: 22 MPa (yield), 21 MPa (breaking)
[0391] Elongation: 4%
EXAMPLE 26
[0392] Using 2-hydroxyisocaproic acid and phenyllactic acid
obtained through the same procedure as in Example 25, a polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 13 parts by weight of the 2-hydroxyisocaproic acid, 16 parts
by weight of the phenyllactic acid and 0.052 part by weight of tin
powder were put into it and 320 parts by weight of diphenyl ether
was added thereto to effect azeotropic dehydration at 130.degree.
C./12 mmHg, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 48 hours,
and the polyester copolymer obtained had a weight-average molecular
weight of 290,000.
[0393] The polyester copolymer thus obtained, having a
weight-average molecular weight of 290,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0394] Thickness: 38 to 39 .mu.m
[0395] Tensile strength: 78 MPa (yield), 77 MPa (breaking)
[0396] Elongation: 23%
EXAMPLE 27
[0397] 340 parts by weight of cellulose (KC FLOCK W-100, trade
name; available from Nippon Seishi K.K.) was introduced into 10,250
parts by weight of an enzyme solution, and these were stirred at
45.degree. C. for 8 hours. As the enzyme solution, used was a
solution prepared by dissolving 34 parts by weight of cellulase
(MEISELASE, trade name; available from Meiji Seika Kaisha, Ltd.) in
10,000 parts by weight of an aqueous acetic acid/sodium acetate
solution (pH 4.5). After the reaction was completed, 670 parts by
weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 200 parts by
weight of glucose.
[0398] The .sup.13C-NMR (100 MHz; internal standard reference
material: tetramethylsilane) of the glucose obtained was measured
with FT-NMR DPX400, manufactured by Bruker Co. Its chemical shifts
.delta. (ppm) were as follows:
[0399] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0400] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0401] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0402] 200 parts by weight of this glucose was mixed with 11,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of lactic acid/phenyllactic acid productive
strain HICA432 isolated in the manner as described previously was
added thereto by means of a syringe in the state the bottle was
kept hermetically stoppered, followed by static culture at
30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 12 parts by weight of lactic acid and
10 parts by weight of phenyllactic acid was obtained.
[0403] The results of analysis of the lactic acid are shown
below.
[0404] .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 1.25
(d, J=6.8 Hz, 3H), 4.07 (q, J=6.8 Hz, 1H).
[0405] The results of analysis of the phenyllactic acid are also
shown below.
[0406] .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 2.82,
2.95, 4.16, 7.25.
[0407] The stereostructure of the lactic acid was also evaluated
using an optically active column (RESTEK Column 13113, trade name;
available from Uniflex Co.). As the result, it was ascertained that
the lactic acid obtained was in the DL-form.
[0408] Meanwhile, the stereostructure of the phenyllactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0409] Using the reactor having a Dean Stark trap, 12 parts by
weight of the lactic acid, 10 parts by weight of the phenyllactic
acid and 0.044 part by weight of tin dichloride were put into it
and 220 parts by weight of mesitylene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 40 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 150,000.
[0410] The polyester copolymer thus obtained, having a
weight-average molecular weight of 150,000, was dissolved in
chloroform. From the solution obtained, film was formed by casting.
The film formed was colorless, and had the following physical
properties.
[0411] Thickness: 40 to 41 .mu.m
[0412] Tensile strength: 63 MPa (yield), 61 MPa (breaking)
[0413] Elongation: 7%
EXAMPLE 28
[0414] Using lactic acid and phenyllactic acid obtained through the
same procedure as in Example 27, a polyester copolymer was
synthesized. Using the reactor having a Dean Stark trap, 12 parts
by weight of the lactic acid, 10 parts by weight of the
phenyllactic acid and 0.04 part by weight of zinc powder were put
into it and 200 parts by weight of 1,3-dichlorobenzene was added
thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 38 hours, and
the polyester copolymer obtained had a weight-average molecular
weight of 100,000.
[0415] The polyester copolymer thus obtained, having a
weight-average molecular weight of 100,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0416] Thickness: 39 to 40 .mu.m
[0417] Tensile strength: 51 MPa (yield), 49 MPa (breaking)
[0418] Elongation: 6%
EXAMPLE 29
[0419] Reclaimed paper for PPC (EN-500, A4, available from CANON
SALES CO., INC.) having been used (a copy had been taken on one
side using a copying machine) was cut in a size of 5 mm square, and
500 parts by weight of the same was introduced into 15,050 parts by
weight of an enzyme solution, followed by stirring at 45.degree. C.
for 10 hours. As the enzyme solution, used was a solution prepared
by dissolving 50 parts by weight of cellulase (MEISELASE TP60,
trade name; available from Meiji Seika Kaisha, Ltd.) in 15,000
parts by weight of an aqueous acetic acid/sodium acetate solution
(pH 4.5). After the reaction was completed, 1,000 parts by weight
of methanol was added to the reaction mixture, and thereafter the
water-soluble residue formed was filtered off therefrom. The
reaction mixture was further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. The resultant reaction mixture was
separated and purified to obtain 280 parts by weight of
glucose.
[0420] 280 parts by weight of this glucose was mixed with 15,400
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 154 parts by weight of a
pre-culture fluid of lactic acid/phenyllactic acid productive
strain HICA432 isolated in the manner as described previously was
added thereto by means of a syringe in the state the bottle was
kept hermetically stoppered, followed by static culture at
30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 18 parts by weight of lactic acid and
4 parts by weight of phenyllactic acid was obtained.
[0421] Using the reactor having a Dean Stark trap, 18 parts by
weight of the lactic acid, 4 parts by weight of the phenyllactic
acid and 0.04 part by weight of tin oxide were put into it and 210
parts by weight of bromobenzene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 45 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 200,000.
[0422] The polyester copolymer thus obtained, having a
weight-average molecular weight of 200,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0423] Thickness: 39 to 40 .mu.m
[0424] Tensile strength: 67 MPa (yield), 66 MPa (breaking)
[0425] Elongation: 11%
EXAMPLE 30
[0426] Using lactic acid and phenyllactic acid obtained through the
same procedure as in Example 29, a polyester copolymer was
synthesized. Using the reactor having a Dean Stark trap, 18 parts
by weight of the lactic acid, 4 parts by weight of the phenyllactic
acid and 0.036 part by weight of p-toluenesulfonic acid were put
into it and 200 parts by weight of 1,2-dichlorobenzene was added
thereto to effect azeotropic dehydration, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 30 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 40,000.
[0427] The polyester copolymer thus obtained, having a
weight-average molecular weight of 40,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0428] Thickness: 39 to 40 .mu.m
[0429] Tensile strength: 20 MPa (yield), 19 MPa (breaking)
[0430] Elongation: 2%
EXAMPLE 31
[0431] 370 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was introduced into 3,300 parts by
weight of water and was dissolved therein with heating. To the
aqueous solution formed, 3,700 parts by weight of 3 mol/l sulfuric
acid was added, followed by stirring at 80.degree. C. for 5 hours
to carry out reaction. After the reaction was completed, anhydrous
sodium carbonate was added to neutralize the aqueous solution,
which was then further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. Then, the resultant reaction
mixture was separated and purified to obtain 220 parts by weight of
glucose.
[0432] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0433] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0434] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0435] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0436] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 3 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure.
Thereafter, the solid content having remained was heated under
reduced pressure. The gas having sublimated was cooled and the
solid matter having precipitated was collected to obtain 10 parts
by weight of 2-hydroxyisocaproic acid.
[0437] The .sup.1C-NMR (100 MHz, TMS, CDCl.sub.3) of the
2-hydroxyisocaproic acid thus obtained was measured to obtain the
results as follows: (.delta./ppm); 180.25, 68.95, 43.16, 24.45,
23.20, 21.42. Thus, it was ascertained that the desired
2-hydroxyisocaproic acid was obtained.
[0438] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
2-hydroxyisocaproic acid obtained was in the L-form.
[0439] Using a reactor having a Dean Stark trap, 10 parts by weight
of the 2-hydroxyisocaproic acid and 0.02 part by weight of tin
dichloride were put into it and 100 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 40 hours,
and the aliphatic polyester obtained had a weight-average molecular
weight of 90,000.
[0440] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was also
measured to obtain the results (.delta./ppm) of 169.78, 71.38,
39.33, 24.53, 23.00, 21.43. Thus, it was ascertained that the
desired aliphatic polyester was synthesized.
[0441] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 90,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0442] Thickness: 38 to 39 .mu.m
[0443] Tensile strength: 48 MPa (yield), 48 MPa (breaking)
[0444] Elongation: 5%
EXAMPLE 32
[0445] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 31, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 10 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of zinc
chloride were put into it and 100 parts by weight of
1,3-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 45 hours, and the aliphatic polyester
obtained had a weight-average molecular weight of 140,000.
[0446] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 140,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0447] Thickness: 39 to 40 .mu.m
[0448] Tensile strength: 57 MPa (yield), 56 MPa (breaking)
[0449] Elongation: 9%
EXAMPLE 33
[0450] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 31, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 9 parts by weight of
the 2-hydroxyisocaproic acid and 0.018 part by weight of tin
octylate were put into it and 90 parts by weight of mesitylene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 40 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 50,000.
[0451] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 31 was obtained, and it was ascertained
that the desired aliphatic polyester was obtained.
[0452] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0453] Thickness: 38 to 39 .mu.m
[0454] Tensile strength: 20 MPa (yield), 20 MPa (breaking)
[0455] Elongation: 3%
EXAMPLE 34
[0456] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 31, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 9 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of tin powder
were put into it and 100 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 190,000.
[0457] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0458] Thickness: 39 to 40 .mu.m
[0459] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0460] Elongation: 13%
EXAMPLE 35
[0461] 370 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was introduced into 3,300 parts by
weight of water and was dissolved therein with heating. To the
aqueous solution formed, 3,700 parts by weight of 3 mol/l sulfuric
acid was added, followed by stirring at 80.degree. C. for 5 hours
to carry out reaction. After the reaction was completed, anhydrous
sodium carbonate was added to neutralize the aqueous solution,
which was then further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. Then, the resultant reaction
mixture was separated and purified to obtain 220 parts by weight of
glucose.
[0462] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0463] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0464] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0465] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0466] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 3 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure.
Thereafter, the solid content having remained was heated under
reduced pressure. The gas having sublimated was cooled and the
solid matter having precipitated was collected to obtain 10 parts
by weight of 2-hydroxyisocaproic acid.
[0467] The .sup.13C-NMR (100 MHz, CDCl.sub.3) of this
2-hydroxyisocaproic acid was measured to obtain the results
(.delta./ppm) of 180.25, 68.95, 43.16, 24.45, 23.20, 21.42. Thus,
it was ascertained that the desired 2-hydroxyisocaproic acid was
obtained.
[0468] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid and 0.2 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 8.2 parts by weight
of a cyclic dimer lactide.
[0469] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the cyclic
dimer lactide obtained was measured to obtain the results
(.delta./ppm) of 167.33, 74.14, 38.87, 23.89, 23.03, 21.33. Thus,
it was ascertained that the desired cyclic dimer lactide was
obtained.
[0470] 8.2 parts by weight of the cyclic dimer lactide and 0.01
part by weight of tin chloride were heated at 150.degree. C. for 12
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 180,000.
[0471] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
aliphatic polyester was measured to obtain the results
(.delta./ppm) of 169.78, 71.38, 39.33, 24.53, 23.00, 21.43. Thus,
it was ascertained that the desired aliphatic polyester was
synthesized.
[0472] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0473] Thickness: 38 to 39 .mu.m
[0474] Tensile strength: 68 MPa (yield), 68 MPa (breaking)
[0475] Elongation: 13%
EXAMPLE 36
[0476] Using a cyclic dimer lactide obtained through the same
procedure as in Example 35, an aliphatic polyester was synthesized.
That is, 8.2 parts by weight of the cyclic dimer lactide and 0.01
part by weight of zinc chloride were heated at 120.degree. C. for 5
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 50,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 35 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0477] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0478] Thickness: 39 to 40 .mu.m
[0479] Tensile strength: 29 MPa (yield), 29 MPa (breaking)
[0480] Elongation: 4%
EXAMPLE 37
[0481] Using a cyclic dimer lactide obtained through the same
procedure as in Example 35, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic dimer lactide and 0.008
part by weight of tin octylate were heated at 180.degree. C. for 30
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 680,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 35 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0482] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 680,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0483] Thickness: 38 to 39 .mu.m
[0484] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0485] Elongation: 30%
EXAMPLE 38
[0486] Using a cyclic dimer lactide obtained through the same
procedure as in Example 35, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester hus obtained had a
weight-average molecular weight of 390,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 35 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0487] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 390,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0488] Thickness: 39 to 40 .mu.m
[0489] Tensile strength: 88 MPa (yield), 87 MPa (breaking)
[0490] Elongation: 22%
EXAMPLE 39
[0491] 370 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was introduced into 3,300 parts by
weight of water and was dissolved therein with heating. To the
aqueous solution formed, 3,700 parts by weight of 3 mol/l sulfuric
acid was added, followed by stirring at 80.degree. C. for 5 hours
to carry out reaction. After the reaction was completed, anhydrous
sodium carbonate was added to neutralize the aqueous solution,
which was then further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. Then, the resultant reaction
mixture was separated and purified to obtain 220 parts by weight of
glucose.
[0492] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0493] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0494] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0495] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0496] 220 parts by weight of this glucose was mixed with 12,100
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 121 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by purification
to obtain 10 parts by weight of phenyllactic acid.
[0497] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
phenyllactic acid thus obtained was measured to obtain the results
(.delta./ppm) of 177.92, 137.63, 130.30, 129.46, 127.82, 72.05,
40.38, and it was ascertained that the desired phenyllactic acid
was obtained.
[0498] Using the reactor having a Dean Stark trap, 10 parts by
weight of the phenyllactic acid and 0.2 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 8.7 parts by weight
of a cyclic diner lactide.
[0499] 8.7 parts by weight of the cyclic diner lactide and 0.01
part by weight of tin chloride were heated at 160.degree. C. for 10
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 190,000.
[0500] The aromatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0501] Thickness: 39 to 40 .mu.m
[0502] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0503] Elongation: 12%
EXAMPLE 40
[0504] Using a cyclic dimer lactide obtained through the same
procedure as in Example 39, an aromatic polyester was synthesized.
That is, 8.7 parts by weight of the cyclic dimer lactide and 0.01
part by weight of zinc chloride were heated at 120.degree. C. for 5
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 50,000.
[0505] The aromatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0506] Thickness: 40 to 41 .mu.m
[0507] Tensile strength: 31 MPa (yield), 30 MPa (breaking)
[0508] Elongation: 3%
EXAMPLE 41
[0509] Using a cyclic dimer lactide obtained through the same
procedure as in Example 39, an aromatic polyester was synthesized.
That is, 7.8 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin octylate were heated at 180.degree. C. for 33
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 700,000.
[0510] The aromatic polyester thus obtained, having a
weight-average molecular weight of 700,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0511] Thickness: 39 to 40 .mu.m
[0512] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0513] Elongation: 25%
EXAMPLE 42
[0514] Using a cyclic dimer lactide obtained through the same
procedure as in Example 39, an aromatic polyester was synthesized.
That is, 7.8 parts by weight of the cyclic dimer lactide and 0.006
part by weight of tin powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 380,000.
[0515] The aromatic polyester thus obtained, having a
weight-average molecular weight of 380,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0516] Thickness: 38 to 39 .mu.m
[0517] Tensile strength: 87 MPa (yield), 86 MPa (breaking)
[0518] Elongation: 16%
EXAMPLE 43
[0519] 340 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was introduced into 3,000 parts by
weight of water and was dissolved therein with heating. To the
aqueous solution formed, 3,400 parts by weight of 3 mol/l sulfuric
acid was added, followed by stirring at 80.degree. C. for 5 hours
to carry out reaction. After the reaction was completed, anhydrous
sodium carbonate was added to neutralize the aqueous solution,
which was then further passed through an ion-exchange column
(AMBERLITE IR-120B, trade name; available from Orugano K.K.), and
the solvent was evaporated off. Then, the resultant reaction
mixture was separated and purified to obtain 200 parts by weight of
glucose.
[0520] The .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) of the glucose
obtained was measured with FT-NMR DPX400, manufactured by Bruker
Co. Its chemical shifts .delta. (ppm) were as follows:
[0521] .alpha.-Type: 92.12, 73.04, 72.29, 71.80, 70.58, 61.20;
[0522] .beta.-Type: 96.79, 76.70, 76.59, 74.78, 70.30, 61.00.
[0523] From the above results of measurement, it was ascertained
that the desired glucose was obtained.
[0524] 200 parts by weight of this glucose was mixed with 11,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/lactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 10 parts by weight of
2-hydroxyisocaproic acid and 12 parts by weight of lactic acid was
obtained.
[0525] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); lactic acid: 1.25 (d, J=6.8 Hz, 3H), 4.07 (q, J=6.8
Hz, 1H).
[0526] Its .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) was also
measured to obtain the results (.delta./ppm) as follows:
2-hydroxyisocaproic acid: 21.43, 23.12, 23.84, 42.84, 68.07,
176.23; lactic acid: 20.39, 65.82, 176.42.
[0527] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0528] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the lactic acid obtained was in the DL-form.
[0529] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid, 12 parts by weight of the
lactic acid and 0.044 part by weight of tin dichloride were put
into it and 220 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the polyester
copolymer obtained had a weight-average molecular weight of
170,000.
[0530] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was measured to
obtain the results (.delta./ppm) of 16.66, 21.43, 22.99, 24.55,
39.30, 68.97, 71.37, 169.51, 169.76. Thus, it was ascertained that
the desired aliphatic polyester copolymer was synthesized.
[0531] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 170,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0532] Thickness: 38 to 39 .mu.m
[0533] Tensile strength: 61 MPa (yield), 59 MPa (breaking)
[0534] Elongation: 14%
EXAMPLE 44
[0535] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 43, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the lactic acid and 0.04 part by weight of zinc powder
were put into it and 200 parts by weight of 1,3-dichlorobenzene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 38 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 100,000.
[0536] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 43 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0537] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 100,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0538] Thickness: 39 to 40 .mu.m
[0539] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0540] Elongation: 6%
EXAMPLE 45
[0541] 200 parts by weight of glucose obtained through the same
procedure as in Example 43 was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 110 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid/lactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by analysis by
NMR. As the result, it was ascertained that a mixture of 9 parts by
weight of 2-hydroxyisocaproic acid and 11 parts by weight of lactic
acid was obtained.
[0542] Using the reactor having a Dean Stark trap, 9 parts by
weight of the 2-hydroxyisocaproic acid, 11 parts by weight of the
lactic acid and 0.04 part by weight of tin octylate were put into
it and 210 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 36 hours, and the aliphatic
polyester copolymer obtained had a weight-average molecular weight
of 60,000.
[0543] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 43 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0544] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 60,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0545] Thickness: 38 to 39 .mu.m
[0546] Tensile strength: 22 MPa (yield), 22 MPa (breaking)
[0547] Elongation: 3%
EXAMPLE 46
[0548] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 45, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 9 parts by weight of the 2-hydroxyisocaproic acid, 11 parts
by weight of the lactic acid and 0.036 part by weight of tin powder
were put into it and 260 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 290,000.
[0549] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 43 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0550] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 290,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0551] Thickness: 39 to 40 .mu.m
[0552] Tensile strength: 74 MPa (yield), 73 MPa (breaking)
[0553] Elongation: 23%
EXAMPLE 47
[0554] 200 parts by weight of glucose obtained through the same
procedure as in Example 43 was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with a mixed gas of 98% of nitrogen and 2% of
oxygen to bring the inside of the bottle into a slightly aerobic
condition, the bottle was hermetically stoppered with a butyl
rubber stopper, which was then treated in an autoclave (121.degree.
C., 98 kPa pressure, 10 minutes). Thereafter, the culture medium
treated was cooled to 30.degree. C., and 110 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid/lactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by analysis by NMR. As the result, it was
ascertained that a mixture of 4 parts by weight of
2-hydroxyisocaproic acid and 18 parts by weight of lactic acid was
obtained.
[0555] Using the reactor having a Dean Stark trap, 4 parts by
weight of the 2-hydroxyisocaproic acid, 18 parts by weight of the
lactic acid and 0.04 part by weight of tin oxide were put into it
and 210 parts by weight of bromobenzene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 45 hours, and the aliphatic polyester
copolymer obtained had a weight-average molecular weight of
220,000.
[0556] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 43 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0557] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 220,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0558] Thickness: 37 to 38 .mu.m
[0559] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0560] Elongation: 18%
EXAMPLE 48
[0561] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 47, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 4 parts by weight of the 2-hydroxyisocaproic acid, 18 parts
by weight of the lactic acid and 0.036 part by weight of
p-toluenesulfonic acid were put into it and 200 parts by weight of
1,2-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 30 hours, and the aliphatic polyester
copolymer obtained had a weight-average molecular weight of
40,000.
[0562] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 43 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0563] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 40,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0564] Thickness: 40 to 41 .mu.m
[0565] Tensile strength: 20 MPa (yield), 20 MPa (breaking)
[0566] Elongation: 2%
[0567] The following Examples 49 to 74 concern the polyester
production process comprising the step of obtaining the substituted
.alpha.-hydroxy acid by the direct fermentation of starch with a
microorganism, described in the second embodiment. As the
microorganism, used is an isolated strain of Clostridium
beijerinckii strain HICA432 (FERMP-18373), obtained upon studies of
the ability to further produce the substituted .alpha.-hydroxy acid
from starch in respect of the 2-hydroxyisocaproic acid productive
strain, strain HICA432, used in Examples 1 to 48.
[0568] The strain HICA432 has been ascertained to be capable of
producing not only the 2-hydroxyisocaproic acid but also lactic
acid and phenyllactic acid. Accordingly, in the following, the
strain HICA432 is also called a 2-hydroxyisocaproic acid productive
strain, a lactic acid productive strain, and a phenyllactic acid
productive strain.
EXAMPLE 49
[0569] 250 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 12,100 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 121 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid productive strain HICA432 isolated in the
manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 3 days. Thereafter,
the culture fluid was filtered, and the water and volatile
components of the filtrate obtained were evaporated off under
normal-temperature reduced pressure. Thereafter, the solid content
having remained was heated under reduced pressure. The gas having
sublimated was cooled and the solid matter having precipitated was
collected to obtain 10 parts by weight of 2-hydroxyisocaproic
acid.
[0570] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
2-hydroxyisocaproic acid thus obtained was measured to obtain the
results as follows: (.delta./ppm); 180.25, 68.95, 43.16, 24.45,
23.20, 21.42. Thus, it was ascertained that the desired
2-hydroxyisocaproic acid was obtained.
[0571] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
2-hydroxyisocaproic acid obtained was in the L-form.
[0572] Next, using a reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid and 0.02 part by weight of
tin dichloride were put into it and 100 parts by weight of
mesitylene was added thereto to effect azeotropic dehydration in an
atmosphere of nitrogen, and the water having gathered in the Dean
Stark trap was appropriately removed. The polymerization time was
40 hours, and the aliphatic polyester obtained had a weight-average
molecular weight of 90,000.
[0573] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was also
measured to obtain the results (.delta./ppm) of 169.78, 71.38,
39.33, 24.53, 23.00, 21.43. Thus, it was ascertained that the
desired aliphatic polyester was synthesized.
[0574] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 90,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0575] Thickness: 38 to 39 .mu.m
[0576] Tensile strength: 48 MPa (yield), 48 MPa (breaking)
[0577] Elongation: 5%
EXAMPLE 50
[0578] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 49, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 10 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of zinc
chloride were put into it and 100 parts by weight of
1,3-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 45 hours, and the aliphatic polyester
obtained had a weight-average molecular weight of 140,000.
[0579] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 140,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0580] Thickness: 39 to 40 .mu.m
[0581] Tensile strength: 57 MPa (yield), 56 MPa (breaking)
[0582] Elongation: 9%
EXAMPLE 51
[0583] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 49, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 9 parts by weight of
the 2-hydroxyisocaproic acid and 0.018 part by weight of tin
octylate were put into it and 90 parts by weight of mesitylene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 40 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 50,000.
[0584] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 49 was obtained, and it was ascertained
that the desired aliphatic polyester was obtained.
[0585] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0586] Thickness: 38 to 39 .mu.m
[0587] Tensile strength: 20 MPa (yield), 20 MPa (breaking)
[0588] Elongation: 3%
EXAMPLE 52
[0589] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 49, an aliphatic polyester was synthesized.
Using the reactor having a Dean Stark trap, 9 parts by weight of
the 2-hydroxyisocaproic acid and 0.02 part by weight of tin powder
were put into it and 100 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 190,000.
[0590] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0591] Thickness: 39 to 40 .mu.m
[0592] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0593] Elongation: 13%
EXAMPLE 53
[0594] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 49, it was converted into a cyclic dimer
lactide in the following way.
[0595] Using the reactor having a Dean Stark trap, 9 parts by
weight of the 2-hydroxyisocaproic acid and 0.18 part by weight of
p-toluenesulfonic acid were put into it and 540 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 7.4 parts by weight
of a cyclic dimer lactide.
[0596] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the cyclic
dimer lactide obtained was measured to obtain the results
(.delta./ppm) of 167.33, 74.14, 38.87, 23.89, 23.03, 21.33. Thus,
it was ascertained that the desired cyclic dimer lactide was
obtained.
[0597] 7.4 parts by weight of the cyclic dimer lactide and 0.01
part by weight of tin chloride were heated at 150.degree. C. for 12
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 180,000.
[0598] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
aliphatic polyester was measured to obtain the results
(.delta./ppm) of 169.78, 71.38, 39.33, 24.53, 23.00, 21.43. Thus,
it was ascertained that the desired aliphatic polyester was
synthesized.
[0599] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0600] Thickness: 38 to 39 .mu.m
[0601] Tensile strength: 68 MPa (yield), 68 MPa (breaking)
[0602] Elongation: 13%
EXAMPLE 54
[0603] Using a cyclic dimer lactide obtained through the same
procedure as in Example 53, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic dimer lactide and 0.007
part by weight of zinc powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 390,000. Its 13C-NMR was
measured to find that the same spectrum as that in Example 53 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0604] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 390,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0605] Thickness: 39 to 40 .mu.m
[0606] Tensile strength: 88 MPa (yield), 87 MPa (breaking)
[0607] Elongation: 22%
EXAMPLE 55
[0608] Using a cyclic dimer lactide obtained through the same
procedure as in Example 53, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic dimer lactide and 0.008
part by weight of tin octylate were heated at 180.degree. C. for 30
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 680,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 53 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0609] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 680,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0610] Thickness: 38 to 39 .mu.m
[0611] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0612] Elongation: 30%
EXAMPLE 56
[0613] 250 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 12,100 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 121 parts by weight of a pre-culture fluid of phenyllactic acid
productive strain HICA432 isolated in the manner as described
previously was added thereto by means of a syringe in the state the
bottle was kept hermetically stoppered, followed by static culture
at 30.degree. C. for 3 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by purification to obtain 10 parts by weight of
phenyllactic acid.
[0614] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
phenyllactic acid thus obtained was measured to obtain the results
(.delta./ppm) of 177.92, 137.63, 130.30, 129.46, 127.82, 72.05,
40.38, and it was ascertained that the desired phenyllactic acid
was obtained.
[0615] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
phenyllactic acid obtained was in the L-form.
[0616] Using the reactor having a Dean Stark trap, 10 parts by
weight of the phenyllactic acid and 0.018 part by weight of tin
dichloride were put into it and 100 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 44 hours,
and the aromatic polyester obtained had a weight-average molecular
weight of 180,000.
[0617] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0618] Thickness: 38 to 39 .mu.m
[0619] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0620] Elongation: 12%
EXAMPLE 57
[0621] Using phenyllactic acid obtained through the same procedure
as in Example 56, an aromatic polyester was synthesized. Using the
reactor having a Dean Stark trap, 10 parts by weight of the
phenyllactic acid and 0.02 part by weight of zinc chloride were put
into it and 100 parts by weight of 1,3-dichlorobenzene was added
thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 16 hours, and
the aromatic polyester obtained had a weight-average molecular
weight of 30,000.
[0622] The aromatic polyester thus obtained, having a
weight-average molecular weight of 30,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0623] Thickness: 39 to 40 .mu.m
[0624] Tensile strength: 20 MPa (yield), 19 MPa (breaking)
[0625] Elongation: 2%
EXAMPLE 58
[0626] Using phenyllactic acid obtained through the same procedure
as in Example 56, an aromatic polyester was synthesized. Using the
reactor having a Dean Stark trap, 9 parts by weight of the
phenyllactic acid and 0.015 part by weight of tin oxide were put
into it and 90 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the aromatic
polyester obtained had a weight-average molecular weight of
90,000.
[0627] The aromatic polyester thus obtained, having a
weight-average molecular weight of 90,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0628] Thickness: 38 to 39 .mu.m
[0629] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0630] Elongation: 5%
EXAMPLE 59
[0631] Using phenyllactic acid obtained through the same procedure
as in Example 56, an aromatic polyester was synthesized. Using the
reactor having a Dean Stark trap, 9 parts by weight of the
phenyllactic acid and 0.015 part by weight of tin powder were put
into it and 100 parts by weight of diphenyl ether was added thereto
to effect azeotropic dehydration at 130.degree. C./12 mmHg, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 48 hours, and the aromatic
polyester obtained had a weight-average molecular weight of
250,000.
[0632] The aromatic polyester thus obtained, having a
weight-average molecular weight of 250,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0633] Thickness: 39 to 40 .mu.m
[0634] Tensile strength: 82 MPa (yield), 81 MPa (breaking)
[0635] Elongation: 18%
EXAMPLE 60
[0636] Using phenyllactic acid obtained through the same procedure
as in Example 56, it was converted into a cyclic dimer lactide in
the following way.
[0637] Using the reactor having a Dean Stark trap, 9 parts by
weight of the phenyllactic acid and 0.18 part by weight of
p-toluenesulfonic acid were put into it and 540 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 7.8 parts by weight
of a cyclic dimer lactide. 7.8 parts by weight of the cyclic dimer
lactide and 0.01 part by weight of tin chloride were heated at
160.degree. C. for 10 hours in an atmosphere of nitrogen to effect
ring-opening polymerization. The aromatic polyester thus obtained
had a weight-average molecular weight of 190,000.
[0638] The aromatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0639] Thickness: 39 to 40 .mu.m
[0640] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0641] Elongation: 12%
EXAMPLE 61
[0642] Using a cyclic dimer lactide obtained through the same
procedure as in Example 60, an aromatic polyester was synthesized.
That is, 7.8 parts by weight of the cyclic dimer lactide and 0.006
part by weight of tin powder were heated at 160.degree. C. for 18
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 380,000.
[0643] The aromatic polyester thus obtained, having a
weight-average molecular weight of 380,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0644] Thickness: 38 to 39 .mu.m
[0645] Tensile strength: 87 MPa (yield), 86 MPa (breaking)
[0646] Elongation: 16%
EXAMPLE 62
[0647] Using a cyclic dimer lactide obtained through the same
procedure as in Example 60, an aromatic polyester was synthesized.
That is, 7.8 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin octylate were heated at 180.degree. C. for 33
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 700,000.
[0648] The aromatic polyester thus obtained, having a
weight-average molecular weight of 700,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0649] Thickness: 39 to 40 .mu.m
[0650] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0651] Elongation: 25%
EXAMPLE 63
[0652] 400 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 110 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid/lactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 4 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by analysis by
NMR. As the result, it was ascertained that a mixture of 10 parts
by weight of 2-hydroxyisocaproic acid and 12 parts by weight of
lactic acid was obtained.
[0653] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); lactic acid: 1.25 (d, J=6.8 Hz, 3H), 4.07 (q, J=6.8
Hz, 1H).
[0654] Its .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) was also
measured to obtain the results (.delta./ppm) as follows:
2-hydroxyisocaproic acid: 21.43, 23.12, 23.84, 42.84, 68.07,
176.23; lactic acid: 20.39, 65.82, 176.42.
[0655] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0656] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the lactic acid obtained was in the DL-form.
[0657] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid, 12 parts by weight of the
lactic acid and 0.044 part by weight of tin dichloride were put
into it and 220 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the aliphatic
polyester copolymer obtained had a weight-average molecular weight
of 170,000.
[0658] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was measured to
obtain the results (.delta./ppm) of 16.66, 21.43, 22.99, 24.55,
39.30, 68.97, 71.37, 169.51, 169.76. Thus, it was ascertained that
the desired aliphatic polyester copolymer was synthesized.
[0659] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 170,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0660] Thickness: 38 to 39 .mu.m
[0661] Tensile strength: 61 MPa (yield), 59 MPa (breaking)
[0662] Elongation: 14%
EXAMPLE 64
[0663] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 63, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the lactic acid and 0.04 part by weight of zinc powder
were put into it and 200 parts by weight of 1,3-dichlorobenzene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 38 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 100,000.
[0664] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 63 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0665] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 100,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0666] Thickness: 39 to 40 .mu.m
[0667] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0668] Elongation: 6%
EXAMPLE 65
[0669] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 63, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the lactic acid and 0.04 part by weight of tin
octilate were put into it and 210 parts by weight of mesitylene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 36 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 60,000.
[0670] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 63 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0671] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 60,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0672] Thickness: 38 to 39 .mu.m
[0673] Tensile strength: 22 MPa (yield), 22 MPa (breaking)
[0674] Elongation: 3%
EXAMPLE 66
[0675] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 63, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the lactic acid and 0.036 part by weight of tin powder
were put into it and 260 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the aliphatic polyester copolymer obtained had a weight-average
molecular weight of 290,000.
[0676] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 63 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0677] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 290,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0678] Thickness: 39 to 40 .mu.m
[0679] Tensile strength: 74 MPa (yield), 73 MPa (breaking)
[0680] Elongation: 23%
EXAMPLE 67
[0681] 400 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas to bring the inside of the
bottle into a slightly aerobic condition, the bottle was
hermetically stoppered with a butyl rubber stopper, which was then
treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 110 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid/lactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by analysis by
NMR. As the result, it was ascertained that a mixture of 4 parts by
weight of 2-hydroxyisocaproic acid and 18 parts by weight of lactic
acid was obtained.
[0682] Using the reactor having a Dean Stark trap, 4 parts by
weight of the 2-hydroxyisocaproic acid, 18 parts by weight of the
lactic acid and 0.04 part by weight of tin oxide were put into it
and 210 parts by weight of bromobenzene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 45 hours, and the aliphatic polyester
copolymer obtained had a weight-average molecular weight of
220,000.
[0683] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 63 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0684] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 220,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0685] Thickness: 37 to 38 .mu.m
[0686] Tensile strength: 69 MPa (yield), 67 MPa (breaking)
[0687] Elongation: 18%
EXAMPLE 68
[0688] Using 2-hydroxyisocaproic acid and lactic acid obtained
through the same procedure as in Example 67, an aliphatic polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 4 parts by weight of the 2-hydroxyisocaproic acid, 18 parts
by weight of the lactic acid and 0.036 part by weight of
p-toluenesulfonic acid were put into it and 200 parts by weight of
1,2-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 30 hours, and the aliphatic polyester
copolymer obtained had a weight-average molecular weight of
40,000.
[0689] Its .sup.13C-NMR was also measured to find that the same
spectrum as that in Example 63 was obtained, and it was ascertained
that the desired aliphatic polyester copolymer was synthesized.
[0690] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 40,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0691] Thickness: 40 to 41 .mu.m
[0692] Tensile strength: 20 MPa (yield), 20 MPa (breaking)
[0693] Elongation: 2%
EXAMPLE 69
[0694] 400 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 110 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid/phenyllactic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 6 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure, followed
by analysis by NMR. As the result, it was ascertained that a
mixture of 10 parts by weight of 2-hydroxyisocaproic acid and 12
parts by weight of phenyllactic acid was obtained.
[0695] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); phenyllactic acid: 2.82, 2.95, 4.16, 7.25.
[0696] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0697] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0698] Using the reactor having a Dean Stark trap, 10 parts by
weight of the 2-hydroxyisocaproic acid, 12 parts by weight of the
phenyllactic acid and 0.044 part by weight of tin dichloride were
put into it and 220 parts by weight of mesitylene was added thereto
to effect azeotropic dehydration in an atmosphere of nitrogen, and
the water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the polyester
copolymer obtained had a weight-average molecular weight of
160,000.
[0699] The polyester copolymer thus obtained, having a
weight-average molecular weight of 160,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0700] Thickness: 37 to 38 .mu.m
[0701] Tensile strength: 60 MPa (yield), 60 MPa (breaking)
[0702] Elongation: 13%
EXAMPLE 70
[0703] Using 2-hydroxyisocaproic acid and phenyllactic acid
obtained through the same procedure as in Example 69, a polyester
copolymer was synthesized. Using the reactor having a Dean Stark
trap, 10 parts by weight of the 2-hydroxyisocaproic acid, 12 parts
by weight of the phenyllactic acid and 0.04 part by weight of zinc
powder were put into it and 200 parts by weight of
1,3-dichlorobenzene was added thereto to effect azeotropic
dehydration in an atmosphere of nitrogen, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 38 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 110,000.
[0704] The polyester copolymer thus obtained, having a
weight-average molecular weight of 110,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0705] Thickness: 39 to 40 .mu.m
[0706] Tensile strength: 50 MPa (yield), 49 MPa (breaking)
[0707] Elongation: 7%
EXAMPLE 71
[0708] 400 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 110 parts by weight of a pre-culture fluid of lactic
acid/phenyllactic acid productive strain HICA432 isolated in the
manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 4 days. Thereafter,
the culture fluid was filtered, and the water and volatile
components of the filtrate obtained were evaporated off under
normal-temperature reduced pressure, followed by analysis by NMR.
As the result, it was ascertained that a mixture of 12 parts by
weight of lactic acid and 10 parts by weight of phenyllactic acid
was obtained.
[0709] The results of analysis of the lactic acid are as follows:
.sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 1.25 (d,
J=6.8 Hz, 3H), 4.07 (q, J=6.8 Hz, 1H).
[0710] The results of analysis of the phenyllactic acid are also as
follows:
[0711] .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 2.82,
2.95, 4.16, 7.25.
[0712] The stereostructure of the lactic acid was also evaluated
using an optically active column (RESTEK Column 13113, trade name;
available from Uniflex Co.). As the result, it was ascertained that
the lactic acid obtained was in the DL-form.
[0713] Meanwhile, the stereostructure of the phenyllactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0714] Using the reactor having a Dean Stark trap, 12 parts by
weight of the lactic acid, 10 parts by weight of the phenyllactic
acid and 0.044 part by weight of tin dichloride were put into it
and 220 parts by weight of mesitylene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 40 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 130,000.
[0715] The polyester copolymer thus obtained, having a
weight-average molecular weight of 130,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0716] Thickness: 38 to 39 .mu.m
[0717] Tensile strength: 61 MPa (yield), 60 MPa (breaking)
[0718] Elongation: 6%
EXAMPLE 72
[0719] Using lactic acid and phenyllactic acid obtained through the
same procedure as in Example 71, a polyester copolymer was
synthesized. Using the reactor having a Dean Stark trap, 12 parts
by weight of the lactic acid, 10 parts by weight of the
phenyllactic acid and 0.04 part by weight of zinc powder were put
into it and 200 parts by weight of 1,3-dichlorobenzene was added
thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 38 hours, and
the polyester copolymer obtained had a weight-average molecular
weight of 80,000.
[0720] The polyester copolymer thus obtained, having a
weight-average molecular weight of 80,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0721] Thickness: 39 to 40 .mu.m
[0722] Tensile strength: 49 MPa (yield), 49 MPa (breaking)
[0723] Elongation: 6%
EXAMPLE 73
[0724] 400 parts by weight of starch (available from Wako Pure
Chemical Industries, Ltd.) was mixed with 11,000 parts by weight of
a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2 g/l
of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride and
5 g/l of calcium carbonate), and the mixture formed was injected
into a pressure bottle. After the gaseous-phase portion in the
bottle was displaced with nitrogen gas, the bottle was hermetically
stoppered with a butyl rubber stopper, which was then treated in an
autoclave (121.degree. C., 98 kPa pressure, 10 minutes).
Thereafter, the culture medium treated was cooled to 30.degree. C.,
and 110 parts by weight of a pre-culture fluid of lactic
acid/phenyllactic acid productive strain HICA432 isolated in the
manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 3 days. Thereafter,
the culture fluid was filtered, and the water and volatile
components of the filtrate obtained were evaporated off under
normal-temperature reduced pressure, followed by analysis by NMR.
As the result, it was ascertained that a mixture of 18 parts by
weight of lactic acid and 4 parts by weight of phenyllactic acid
was obtained.
[0725] Using the reactor having a Dean Stark trap, 18 parts by
weight of the lactic acid, 4 parts by weight of the phenyllactic
acid and 0.04 part by weight of tin oxide were put into it and 210
parts by weight of bromobenzene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 45 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 180,000.
[0726] The polyester copolymer thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0727] Thickness: 39 to 40 .mu.m
[0728] Tensile strength: 67 MPa (yield), 64 MPa (breaking)
[0729] Elongation: 10%
EXAMPLE 74
[0730] Using lactic acid and phenyllactic acid obtained through the
same procedure as in Example 73, a polyester copolymer was
synthesized. Using the reactor having a Dean Stark trap, 18 parts
by weight of the lactic acid, 4 parts by weight of the phenyllactic
acid and 0.036 part by weight of p-toluenesulfonic acid were put
into it and 200 parts by weight of 1,2-dichlorobenzene was added
thereto to effect azeotropic dehydration, and the water having
gathered in the Dean Stark trap was appropriately removed. The
polymerization time was 30 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 30,000.
[0731] The polyester copolymer thus obtained, having a
weight-average molecular weight of 30,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0732] Thickness: 39 to 40 .mu.m
[0733] Tensile strength: 19 MPa (yield), 19 MPa (breaking)
[0734] Elongation: 2% The following Examples 75 to 82 concern the
polyester production process comprising the step of obtaining the
substituted .alpha.-hydroxy acid by the fermentation of xylose with
a microorganism, described in the third embodiment.
[0735] As the microorganism, used is an isolated strain of
Clostridium beijerinckii strain HICA432 (FERMP-18373), obtained
upon studies of the ability to further produce the substituted
.alpha.-hydroxy acid from xylose in respect of the
2-hydroxyisocaproic acid productive strain, strain HICA432, used in
Examples 1 to 48.
[0736] The strain HICA432 has been ascertained to be capable of
producing from xylose not only the 2-hydroxyisocaproic acid but
also phenyllactic acid. Accordingly, in the following, the strain
HICA432 is also called a 2-hydroxyisocaproic acid productive strain
and a phenyllactic acid productive strain.
EXAMPLE 75
[0737] 750 parts by weight of hemicellulose was introduced into
3,000 parts by weight of 1% hydrochloric acid, and these were
stirred at 130.degree. C. for 8 hours. After the reaction was
completed, the reaction mixture was neutralized with a 10% sodium
hydroxide solution. Thereafter, 1,800 parts by weight of methanol
was added to the reaction mixture, and thereafter the water-soluble
residue formed was filtered off therefrom. The reaction mixture was
further passed through an ion-exchange column (AMBERLITE IR-120B,
trade name; available from Orugano K.K.), and the solvent was
evaporated off. The resultant reaction mixture was separated and
purified to obtain 550 parts by weight of xylose.
[0738] The xylose thus obtained was identified and ascertained as
such by ion-exchange chromatography (TSKgel Sugar AXG Column,
available from Tosoh Corporation).
[0739] 550 parts by weight of this xylose was mixed with 27,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 270 parts by weight of a
pre-culture fluid of phenyllactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 6 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by purification
to obtain 10 parts by weight of phenyllactic acid.
[0740] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
phenyllactic acid thus obtained was measured to obtain the results
(.delta./ppm) of 177.92, 137.63, 130.30, 129.46, 127.82, 72.05,
40.38, and it was ascertained that the desired phenyllactic acid
was obtained.
[0741] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
phenyllactic acid obtained was in the L-form.
[0742] Using a reactor having a Dean Stark trap, 10 parts by weight
of the phenyllactic acid and 0.018 part by weight of tin dichloride
were put into it and 100 parts by weight of mesitylene was added
thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 44 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 200,000.
[0743] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 200,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0744] Thickness: 38 to 39 .mu.m
[0745] Tensile strength: 70 MPa (yield), 69 MPa (breaking)
[0746] Elongation: 13%
EXAMPLE 76
[0747] Using phenyllactic acid obtained through the same procedure
as in Example 75, a polyester was synthesized. Using the reactor
having a Dean Stark trap, 10 parts by weight of the phenyllactic
acid and 0.02 part by weight of zinc chloride were put into it and
100 parts by weight of 1,3-dichlorobenzene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 16 hours, and the aliphatic
polyester obtained had a weight-average molecular weight of
50,000.
[0748] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 50,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0749] Thickness: 39 to 40 .mu.m
[0750] Tensile strength: 23 MPa (yield), 20 MPa (breaking)
[0751] Elongation: 3%
EXAMPLE 77
[0752] Using phenyllactic acid obtained through the same procedure
as in Example 75, it was converted into a cyclic dimer lactide in
the following way.
[0753] Using the reactor having a Dean Stark trap, 10 parts by
weight of the phenyllactic acid and 0.20 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 8.7 parts by weight
of a cyclic dimer lactide.
[0754] 8.7 parts by weight of the cyclic dimer lactide and 0.01
part by weight of tin chloride were heated at 160.degree. C. for 10
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 190,000.
[0755] The aromatic polyester thus obtained, having a
weight-average molecular weight of 190,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0756] Thickness: 39 to 40 .mu.m
[0757] Tensile strength: 69 MPa (yield), 69 MPa (breaking)
[0758] Elongation: 12%
EXAMPLE 78
[0759] Using a cyclic dimer lactide obtained through the same
procedure as in Example 77, an aromatic polyester was synthesized.
That is, 8.7 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin octylate were heated at 180.degree. C. for 33
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 700,000.
[0760] The aromatic polyester thus obtained, having a
weight-average molecular weight of 700,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0761] Thickness: 39 to 40 .mu.m
[0762] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0763] Elongation: 25%
EXAMPLE 79
[0764] 750 parts by weight of hemicellulose was introduced into
3,000 parts by weight of 1% hydrochloric acid, and these were
stirred at 130.degree. C. for 8 hours. After the reaction was
completed, the reaction mixture was neutralized with a 10% sodium
hydroxide solution. Thereafter, 1,800 parts by weight of methanol
was added to the reaction mixture, and thereafter the water-soluble
residue formed was filtered off therefrom. The reaction mixture was
further passed through an ion-exchange column (AMBERLITE IR-120B,
trade name; available from Orugano K.K.), and the solvent was
evaporated off. The resultant reaction mixture was separated and
purified to obtain 550 parts by weight of xylose.
[0765] The xylose thus obtained was identified and ascertained as
such by ion-exchange chromatography (TSKgel Sugar AXG Column,
available from Tosoh Corporation).
[0766] 550 parts by weight of this xylose was mixed with 27,000
parts by weight of a culture medium (10 g/l of peptone, 5 g/l of
yeast extract, 2 g/l of meat extract, 5 g/l of NaCl, 2 g/l of
cysteine hydrochloride and 5 g/l of calcium carbonate), and the
mixture formed was injected into a pressure bottle. After the
gaseous-phase portion in the bottle was displaced with nitrogen
gas, the bottle was hermetically stoppered with a butyl rubber
stopper, which was then treated in an autoclave (121.degree. C., 98
kPa pressure, 10 minutes). Thereafter, the culture medium treated
was cooled to 30.degree. C., and 270 parts by weight of a
pre-culture fluid of 2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 6 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure, followed
by purification to obtain 12 parts by weight of 2-hydroxyisocaproic
acid.
[0767] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
2-hydroxyisocaproic acid thus obtained was measured to obtain the
results (.delta./ppm) of 180.25, 68.95, 43.16, 24.45, 23.20, 21.42.
Thus, it was ascertained that the desired 2-hydroxyisocaproic acid
was obtained.
[0768] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
phenyllactic acid obtained was in the L-form.
[0769] Using the reactor having a Dean Stark trap, 12 parts by
weight of the 2-hydroxyisocaproic acid and 0.018 part by weight of
tin dichloride were put into it and 100 parts by weight of
mesitylene was added thereto to effect azeotropic dehydration in an
atmosphere of nitrogen, and the water having gathered in the Dean
Stark trap was appropriately removed. The polymerization time was
44 hours, and the polyester obtained had a weight-average molecular
weight of 220,000.
[0770] The polyester thus obtained, having a weight-average
molecular weight of 220,000, was dissolved in chloroform. From the
solution obtained, a film was formed by casting. The film formed
was colorless, and had the following physical properties.
[0771] Thickness: 38 to 39 .mu.m
[0772] Tensile strength: 67 MPa (yield), 67 MPa (breaking)
[0773] Elongation: 16%
EXAMPLE 80
[0774] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 79, a polyester was synthesized. Using the
reactor having a Dean Stark trap, 12 parts by weight of the
2-hydroxyisocaproic acid and 0.02 part by weight of zinc chloride
were put into it and 100 parts by weight of 1,3-dichlorobenzene was
added thereto to effect azeotropic dehydration in an atmosphere of
nitrogen, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 16 hours, and
the aliphatic polyester obtained had a weight-average molecular
weight of 60,000.
[0775] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 60,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0776] Thickness: 39 to 40 .mu.m
[0777] Tensile strength: 23 MPa (yield), 21 MPa (breaking)
[0778] Elongation: 3%
EXAMPLE 81
[0779] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 79, it was converted into a cyclic dimer
lactide in the following way.
[0780] Using the reactor having a Dean Stark trap, 12 parts by
weight of the 2-hydroxyisocaproic acid and 0.24 part by weight of
p-toluenesulfonic acid were put into it and 600 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 9.8 parts by weight
of a cyclic dimer lactide.
[0781] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the cyclic
dimer lactide obtained was measured to obtain the results
(.delta./ppm) of 167.33, 74.14, 38.87, 23.89, 23.03, 21.33. Thus,
it was ascertained that the desired cyclic dimer lactide was
obtained. 9.8 parts by weight of the cyclic dimer lactide and 0.013
part by weight of tin chloride were heated at 150.degree. C. for 12
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 180,000.
[0782] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
aliphatic polyester was measured to obtain the results
(.delta./ppm) of 169.78, 71.38, 39.33, 24.53, 23.00, 21.43. Thus,
it was ascertained that the desired aliphatic polyester was
synthesized.
[0783] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 180,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0784] Thickness: 38 to 39 .mu.m
[0785] Tensile strength: 68 MPa (yield), 68 MPa (breaking)
[0786] Elongation: 13%
EXAMPLE 82
[0787] Using a cyclic dimer lactide obtained through the same
procedure as in Example 81, an aliphatic polyester was synthesized.
That is, 7.4 parts by weight of the cyclic dimer lactide and 0.011
part by weight of tin octylate were heated at 180.degree. C. for 30
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 680,000. Its .sup.13C-NMR was
measured to find that the same spectrum as that in Example 81 was
obtained, and it was ascertained that the desired aliphatic
polyester was obtained.
[0788] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 680,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0789] Thickness: 38 to 39 .mu.m
[0790] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0791] Elongation: 30%
[0792] The following Examples 83 to 91 concern the polyester
production process comprising the step of obtaining the substituted
.alpha.-hydroxy acid by the fermentation of cellulose and xylose
with a microorganism, described in the fourth embodiment.
[0793] As the microorganism, used is an isolated strain of
Clostridium beijerinckii strain HICA432 (FERMP-18373), obtained
upon studies of the ability to further produce the substituted
.alpha.-hydroxy acid from cellulose and xylose in respect of the
2-hydroxyisocaproic acid productive strain, strain HICA432, used in
Examples 1 to 48.
[0794] The strain HICA432 has been ascertained to be capable of
producing from cellulose and xylose not only the
2-hydroxyisocaproic acid but also lactic acid and phenyllactic
acid. Accordingly, in the following, the strain HICA432 is also
called a 2-hydroxyisocaproic acid productive strain, a lactic acid
productive strain and a phenyllactic acid productive strain.
EXAMPLE 83
[0795] Newspapers were cut in a size of 10 mm square, and 500 parts
by weight of the same was introduced into 2,500 parts by weight of
20% sulfuric acid, and these were stirred at 180.degree. C. for 12
hours. After the reaction was completed, the reaction mixture was
neutralized with a 20% sodium hydroxide solution. Thereafter, 300
parts by weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 25 parts by
weight of xylose and 180 parts by weight of glucose.
[0796] The xylose and glucose thus obtained were identified and
ascertained as such by ion-exchange chromatography (TSKgel Sugar
AXG Column, available from Tosoh Corporation). 25 parts by weight
and 180 parts by weight of these xylose and glucose, respectively,
were mixed with 10,000 parts by weight of a culture medium (10 g/l
of peptone, 5 g/l of yeast extract, 2 g/l of meat extract, 5 g/l of
NaCl, 2 g/l of cysteine hydrochloride and 5 g/l of calcium
carbonate), and the mixture formed was injected into a pressure
bottle. After the gaseous-phase portion in the bottle was displaced
with nitrogen gas, the bottle was hermetically stoppered with a
butyl rubber stopper, which was then treated in an autoclave
(121.degree. C., 98 kPa pressure, 10 minutes). Thereafter, the
culture medium treated was cooled to 30.degree. C., and 100 parts
by weight of a pre-culture fluid of phenyllactic acid productive
strain HICA432 isolated in the manner as described previously was
added thereto by means of a syringe in the state the bottle was
kept hermetically stoppered, followed by static culture at
30.degree. C. for 6 days. Thereafter, the culture fluid was
filtered, and the water and volatile components of the filtrate
obtained were evaporated off under normal-temperature reduced
pressure, followed by purification to obtain 9 parts by weight of
phenyllactic acid.
[0797] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
phenyllactic acid thus obtained was measured to obtain the results
(.delta./ppm) of 177.92, 137.63, 130.30, 129.46, 127.82, 72.05,
40.38, and it was ascertained that the desired phenyllactic acid
was obtained.
[0798] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
phenyllactic acid obtained was in the L-form.
[0799] Using the reactor having a Dean Stark trap, 9 parts by
weight of the phenyllactic acid and 0.018 part by weight of tin
dichloride were put into it and 100 parts by weight of mesitylene
was added thereto to effect azeotropic dehydration in an atmosphere
of nitrogen, and the water having gathered in the Dean Stark trap
was appropriately removed. The polymerization time was 44 hours,
and the aliphatic polyester obtained had a weight-average molecular
weight of 120,000.
[0800] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 120,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0801] Thickness: 39 to 40 .mu.m
[0802] Tensile strength: 50 MPa (yield), 49 MPa (breaking)
[0803] Elongation: 5%
EXAMPLE 84
[0804] Using phenyllactic acid obtained through the same procedure
as in Example 83, a polyester was synthesized. Using the reactor
having a Dean Stark trap, 9 parts by weight of the phenyllactic
acid and 0.015 part by weight of tin powder were put into it and
100 parts by weight of diphenyl ether was added thereto to effect
azeotropic dehydration at 130.degree. C./12 mmHg, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 48 hours, and the polyester obtained
had a weight-average molecular weight of 220,000.
[0805] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 220,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0806] Thickness: 39 to 40 .mu.m
[0807] Tensile strength: 74 MPa (yield), 73 MPa (breaking)
[0808] Elongation: 14%
EXAMPLE 85
[0809] Using phenyllactic acid obtained through the same procedure
as in Example 83, it was converted into a cyclic dimer lactide in
the following way.
[0810] Using the reactor having a Dean Stark trap, 9 parts by
weight of the phenyllactic acid and 0.18 part by weight of
p-toluenesulfonic acid were put into it and 540 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 7.8 parts by weight
of a cyclic dimer lactide.
[0811] 7.8 parts by weight of the cyclic dimer lactide and 0.007
part by weight of tin octylate were heated at 180.degree. C. for 33
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aromatic polyester thus obtained had a
weight-average molecular weight of 700,000.
[0812] The aromatic polyester thus obtained, having a
weight-average molecular weight of 700,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0813] Thickness: 39 to 40 .mu.m
[0814] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0815] Elongation: 25%
EXAMPLE 86
[0816] Newspapers were cut in a size of 10 mm square, and 500 parts
by weight of the same was introduced into 2,500 parts by weight of
20% sulfuric acid, and these were stirred at 180.degree. C. for 12
hours. After the reaction was completed, the reaction mixture was
neutralized with a 20% sodium hydroxide solution. Thereafter, 300
parts by weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 25 parts by
weight of xylose and 180 parts by weight of glucose.
[0817] The xylose and glucose thus obtained were identified and
ascertained as such by ion-exchange chromatography (TSKgel Sugar
AXG Column, available from Tosoh Corporation).
[0818] 25 parts by weight and 180 parts by weight of these xylose
and glucose, respectively, were mixed with 10,000 parts by weight
of a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2
g/l of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride
and 5 g/l of calcium carbonate), and the mixture formed was
injected into a pressure bottle. After the gaseous-phase portion in
the bottle was displaced with nitrogen gas, the bottle was
hermetically stoppered with a butyl rubber stopper, which was then
treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 100 parts by weight of a pre-culture fluid of
phenyllactic acid/2-hydroxyisocaproic acid productive strain
HICA432 isolated in the manner as described previously was added
thereto by means of a syringe in the state the bottle was kept
hermetically stoppered, followed by static culture at 30.degree. C.
for 6 days. Thereafter, the culture fluid was filtered, and the
water and volatile components of the filtrate obtained were
evaporated off under normal-temperature reduced pressure, followed
by analysis by NMR. As the result, it was ascertained that a
mixture of 8.5 parts by weight of phenyllactic acid and 8.0 parts
by weight of 2-hydroxyisocaproic acid was obtained.
[0819] Its 1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); phenyllactic acid: 2.82, 2.95, 4.16, 7.25.
[0820] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0821] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0822] Using the reactor having a Dean Stark trap, 8.0 parts by
weight of the 2-hydroxyisocaproic acid, 8.5 parts by weight of the
phenyllactic acid and 0.019 part by weight of tin dichloride were
put into it and 100 parts by weight of mesitylene was added thereto
to effect azeotropic dehydration in an atmosphere of nitrogen, and
the water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the polyester
copolymer obtained had a weight-average molecular weight of
160,000.
[0823] The polyester copolymer thus obtained, having a
weight-average molecular weight of 160,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0824] Thickness: 37 to 38 .mu.m
[0825] Tensile strength: 60 MPa (yield), 60 MPa (breaking)
[0826] Elongation: 13%
EXAMPLE 87
[0827] Newspapers were cut in a size of 10 mm square, and 500 parts
by weight of the same was introduced into 2,500 parts by weight of
20% sulfuric acid, and these were stirred at 180.degree. C. for 12
hours. After the reaction was completed, the reaction mixture was
neutralized with a 20% sodium hydroxide solution. Thereafter, 300
parts by weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 25 parts by
weight of xylose and 180 parts by weight of glucose.
[0828] The xylose and glucose thus obtained were identified and
ascertained as such by ion-exchange chromatography (TSKgel Sugar
AXG Column, available from Tosoh Corporation).
[0829] 25 parts by weight and 180 parts by weight of these xylose
and glucose, respectively, were mixed with 10,000 parts by weight
of a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2
g/l of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride
and 5 g/l of calcium carbonate), and the mixture formed was
injected into a pressure bottle. After the gaseous-phase portion in
the bottle was displaced with nitrogen gas, the bottle was
hermetically stoppered with a butyl rubber stopper, which was then
treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 100 parts by weight of a pre-culture fluid of
phenyllactic acid/lactic acid productive strain HICA432 isolated in
the manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 4 days. Thereafter,
the culture fluid was filtered, and the water and volatile
components of the filtrate obtained were evaporated off under
normal-temperature reduced pressure, followed by analysis by NMR.
As the result, it was ascertained that a mixture of 4 parts by
weight of phenyllactic acid and 5 parts by weight of lactic acid
was obtained.
[0830] The results of analysis of the lactic acid are as
follows:
[0831] .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 1.25
(d, J=6.8 Hz, 3H), 4.07 (q, J=6.8 Hz, 1H).
[0832] The results of analysis of the phenyllactic acid are also as
follows:
[0833] .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) .delta./ppm: 2.82,
2.95, 4.16, 7.25.
[0834] The stereostructure of the lactic acid was also evaluated
using an optically active column (RESTEK Column 13113, trade name;
available from Uniflex Co.). As the result, it was ascertained that
the lactic acid obtained was in the DL-form.
[0835] Meanwhile, the stereostructure of the phenyllactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the phenyllactic acid obtained was in the
L-form.
[0836] Using the reactor having a Dean Stark trap, 5 parts by
weight of the lactic acid, 4 parts by weight of the phenyllactic
acid and 0.018 part by weight of tin dichloride were put into it
and 100 parts by weight of mesitylene was added thereto to effect
azeotropic dehydration in an atmosphere of nitrogen, and the water
having gathered in the Dean Stark trap was appropriately removed.
The polymerization time was 40 hours, and the polyester copolymer
obtained had a weight-average molecular weight of 130,000.
[0837] The polyester copolymer thus obtained, having a
weight-average molecular weight of 130,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0838] Thickness: 38 to 39 .mu.m
[0839] Tensile strength: 61 MPa (yield), 60 MPa (breaking)
[0840] Elongation: 6%
EXAMPLE 88
[0841] Newspapers were cut in a size of 10 mm square, and 500 parts
by weight of the same was introduced into 2,500 parts by weight of
20% sulfuric acid, and these were stirred at 180.degree. C. for 12
hours. After the reaction was completed, the reaction mixture was
neutralized with a 20% sodium hydroxide solution. Thereafter, 300
parts by weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 22 parts by
weight of xylose and 170 parts by weight of glucose.
[0842] The xylose and glucose thus obtained were identified and
ascertained as such by ion-exchange chromatography (TSKgel Sugar
AXG Column, available from Tosoh Corporation).
[0843] 22 parts by weight and 170 parts by weight of these xylose
and glucose, respectively, were mixed with 10,000 parts by weight
of a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2
g/l of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride
and 5 g/l of calcium carbonate), and the mixture formed was
injected into a pressure bottle. After the gaseous-phase portion in
the bottle was displaced with nitrogen gas, the bottle was
hermetically stoppered with a butyl rubber stopper, which was then
treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 100 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid productive strain HICA432 isolated in the
manner as described previously was added thereto by means of a
syringe in the state the bottle was kept hermetically stoppered,
followed by static culture at 30.degree. C. for 6 days. Thereafter,
the culture fluid was filtered, and the water and volatile
components of the filtrate obtained were evaporated off under
normal-temperature reduced pressure, followed by purification to
obtain 8 parts by weight of 2-hydroxyisocaproic.
[0844] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the
2-hydroxyisocaproic acid thus obtained was measured to obtain the
results (.delta./ppm) of 180.25, 68.95, 43.16, 24.45, 23.20, 21.42.
Thus, it was ascertained that the desired 2-hydroxyisocaproic acid
was obtained.
[0845] Its stereostructure was also evaluated using an optically
active column (CYCLODEX-B, trade name; available from J & W
Scientific Co.). As the result, it was ascertained that the
2-hydroxyisocaproic acid obtained was in the L-form.
[0846] Using the reactor having a Dean Stark trap, 8 parts by
weight of the 2-hydroxyisocaproic acid and 0.018 part by weight of
tin dichloride were put into it and 100 parts by weight of
mesitylene was added thereto to effect azeotropic dehydration in an
atmosphere of nitrogen, and the water having gathered in the Dean
Stark trap was appropriately removed. The polymerization time was
44 hours, and the polyester obtained had a weight-average molecular
weight of 100,000.
[0847] The polyester thus obtained, having a weight-average
molecular weight of 100,000, was dissolved in chloroform. From the
solution obtained, a film was formed by casting. The film formed
was colorless, and had the following physical properties.
[0848] Thickness: 39 to 40 .mu.m
[0849] Tensile strength: 51 MPa (yield), 50 MPa (breaking)
[0850] Elongation: 6%
EXAMPLE 89
[0851] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 88, a polyester was synthesized. Using the
reactor having a Dean Stark trap, 8 parts by weight of the
2-hydroxyisocaproic acid and 0.015 part by weight of tin powder
were put into it and 100 parts by weight of diphenyl ether was
added thereto to effect azeotropic dehydration at 130.degree. C./12
mmHg, and the water having gathered in the Dean Stark trap was
appropriately removed. The polymerization time was 48 hours, and
the polyester obtained had a weight-average molecular weight of
200,000.
[0852] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 200,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0853] Thickness: 39 to 40 .mu.m
[0854] Tensile strength: 62 MPa (yield), 59 MPa (breaking)
[0855] Elongation: 18%
EXAMPLE 90
[0856] Using 2-hydroxyisocaproic acid obtained through the same
procedure as in Example 88, it was converted into a cyclic dimer
lactide in the following way.
[0857] Using the reactor having a Dean Stark trap, 8 parts by
weight of the 2-hydroxyisocaproic acid and 0.16 part by weight of
p-toluenesulfonic acid were put into it and 400 parts by weight of
toluene was added thereto to effect azeotropic dehydration for 30
hours in an atmosphere of nitrogen, and the water having gathered
in the Dean Stark trap was appropriately removed. After the
reaction was completed, the reaction mixture was washed with sodium
hydrogencarbonate, and the toluene was evaporated off. The residue
formed was recrystallized from ether to obtain 6.5 parts by weight
of a cyclic dimer lactide.
[0858] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of the cyclic
dimer lactide obtained was measured to obtain the results
(.delta./ppm) of 167.33, 74.14, 38.87, 23.89, 23.03, 21.33. Thus,
it was ascertained that the desired cyclic dimer lactide was
obtained.
[0859] 6.5 parts by weight of the cyclic dimer lactide and 0.010
part by weight of tin octylate were heated at 180.degree. C. for 30
hours in an atmosphere of nitrogen to effect ring-opening
polymerization. The aliphatic polyester thus obtained had a
weight-average molecular weight of 680,000.
[0860] The .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) of this
aliphatic polyester was measured to obtain the results
(.delta./ppm) of 169.78, 71.38, 39.33, 24.53, 23.00, 21.43. Thus,
it was ascertained that the desired aliphatic polyester was
synthesized.
[0861] The aliphatic polyester thus obtained, having a
weight-average molecular weight of 680,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0862] Thickness: 38 to 39 .mu.m
[0863] Tensile strength: 98 MPa (yield), 98 MPa (breaking)
[0864] Elongation: 30%
EXAMPLE 91
[0865] Newspapers were cut in a size of 10 mm square, and 500 parts
by weight of the same was introduced into 2,500 parts by weight of
20% sulfuric acid, and these were stirred at 180.degree. C. for 12
hours. After the reaction was completed, the reaction mixture was
neutralized with a 20% sodium hydroxide solution. Thereafter, 300
parts by weight of methanol was added to the reaction mixture, and
thereafter the water-soluble residue formed was filtered off
therefrom. The reaction mixture was further passed through an
ion-exchange column (AMBERLITE IR-120B, trade name; available from
Orugano K.K.), and the solvent was evaporated off. The resultant
reaction mixture was separated and purified to obtain 25 parts by
weight of xylose and 180 parts by weight of glucose.
[0866] The xylose and glucose thus obtained were identified and
ascertained as such by ion-exchange chromatography (TSKgel Sugar
AXG Column, available from Tosoh Corporation).
[0867] 25 parts by weight and 180 parts by weight of these xylose
and glucose, respectively, were mixed with 10,000 parts by weight
of a culture medium (10 g/l of peptone, 5 g/l of yeast extract, 2
g/l of meat extract, 5 g/l of NaCl, 2 g/l of cysteine hydrochloride
and 5 g/l of calcium carbonate), and the mixture formed was
injected into a pressure bottle. After the gaseous-phase portion in
the bottle was displaced with nitrogen gas, the bottle was
hermetically stoppered with a butyl rubber stopper, which was then
treated in an autoclave (121.degree. C., 98 kPa pressure, 10
minutes). Thereafter, the culture medium treated was cooled to
30.degree. C., and 100 parts by weight of a pre-culture fluid of
2-hydroxyisocaproic acid/lactic acid productive strain HICA432
isolated in the manner as described previously was added thereto by
means of a syringe in the state the bottle was kept hermetically
stoppered, followed by static culture at 30.degree. C. for 3 days.
Thereafter, the culture fluid was filtered, and the water and
volatile components of the filtrate obtained were evaporated off
under normal-temperature reduced pressure, followed by analysis by
NMR. As the result, it was ascertained that a mixture of 7 parts by
weight of 2-hydroxyisocapric acid and 6 parts by weight of lactic
acid was obtained.
[0868] Its .sup.1H-NMR (400 MHz, TMS, DMSO-d.sub.6) was measured to
obtain the results (.delta./ppm) as follows: 2-hydroxyisocaproic
acid: 0.88 (t, 6H), 1.37 to 1.48 (m, 2H), 1.72 to 1.82 (m, 1H),
3.94 (dd, 1H); lactic acid: 1.25 (d, J=6.8 Hz, 3H), 4.07 (q, J=6.8
Hz, 1H).
[0869] Its .sup.13C-NMR (100 MHz, TMS, DMSO-d.sub.6) was also
measured to obtain the results (.delta./ppm) as follows:
2-hydroxyisocaproic acid: 21.43, 23.12, 23.84, 42.84, 68.07,
176.23; lactic acid: 20.39, 65.82, 176.42.
[0870] The stereostructure of the 2-hydroxyisocaproic acid was also
evaluated using an optically active column (CYCLODEX-B, trade name;
available from J & W Scientific Co.). As the result, it was
ascertained that the 2-hydroxyisocaproic acid obtained was in the
L-form.
[0871] Meanwhile, the stereostructure of the lactic acid was
evaluated using an optically active column (RESTEK Column 13113,
trade name; available from Uniflex Co.). As the result, it was
ascertained that the lactic acid obtained was in the DL-form.
[0872] Using the reactor having a Dean Stark trap, 7 parts by
weight of the 2-hydroxyisocaproic acid, 6 parts by weight of the
lactic acid and 0.018 part by weight of tin dichloride were put
into it and 100 parts by weight of mesitylene was added thereto to
effect azeotropic dehydration in an atmosphere of nitrogen, and the
water having gathered in the Dean Stark trap was appropriately
removed. The polymerization time was 40 hours, and the aliphatic
polyester copolymer obtained had a weight-average molecular weight
of 170,000.
[0873] Its .sup.13C-NMR (100 MHz, TMS, CDCl.sub.3) was measured to
obtain the results (.delta./ppm) of 16.66, 21.43, 22.99, 24.55,
39.30, 68.97, 71.37, 169.51, 169.76. Thus, it was ascertained that
the desired aliphatic polyester copolymer was synthesized.
[0874] The aliphatic polyester copolymer thus obtained, having a
weight-average molecular weight of 170,000, was dissolved in
chloroform. From the solution obtained, a film was formed by
casting. The film formed was colorless, and had the following
physical properties.
[0875] Thickness: 38 to 39 .mu.m
[0876] Tensile strength: 61 MPa (yield), 59 MPa (breaking)
[0877] Elongation: 14%
* * * * *