U.S. patent application number 09/745169 was filed with the patent office on 2002-08-22 for copolyestercarbonates derived from dimer acids and method for their preparation.
Invention is credited to Davis, Gary Charles, Mobley, David Paul, Nelson, Mark Erik.
Application Number | 20020115816 09/745169 |
Document ID | / |
Family ID | 24995539 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020115816 |
Kind Code |
A1 |
Davis, Gary Charles ; et
al. |
August 22, 2002 |
COPOLYESTERCARBONATES DERIVED FROM DIMER ACIDS AND METHOD FOR THEIR
PREPARATION
Abstract
Copolyestercarbonates comprising carbonate structural units
derived from at least one dihydroxyaromatic compound, preferably
bisphenol A, and ester units derived from a dihydroxyaromatic
compound and a composition comprising at least one C.sub.36 dimer
acid may be prepared by an interfacial phosgenation method
conducted at a pH in the range of about 9-11. The
copolyestercarbonates have properties which are often superior to
those of corresponding polymers prepared, for example, from
dodecanedioic acid.
Inventors: |
Davis, Gary Charles;
(Albany, NY) ; Mobley, David Paul; (Niskayuna,
NY) ; Nelson, Mark Erik; (Mt. Vernon, IN) |
Correspondence
Address: |
GENERAL ELECTRIC COMPANY
CRD PATENT DOCKET ROOM 4A59
P O BOX 8
BUILDING K 1 SALAMONE
SCHENECTADY
NY
12301
US
|
Family ID: |
24995539 |
Appl. No.: |
09/745169 |
Filed: |
December 20, 2000 |
Current U.S.
Class: |
528/196 |
Current CPC
Class: |
C08G 63/64 20130101 |
Class at
Publication: |
528/196 |
International
Class: |
C08G 063/48 |
Claims
What is claimed is:
1. A copolyestercarbonate comprising carbonate structural units of
the formula 3wherein each A.sup.1 is independently a divalent
aliphatic, alicyclic or aromatic radical, and ester units derived
from a dihydroxyaromatic compound of the formula A.sup.1(OH).sub.2
and a composition comprising at least one C.sub.36 dimer acid.
2. The copolyestercarbonate according to claim 1 wherein A.sup.1
has the formula --A.sup.2--Y--A.sup.3--, (II)wherein each of
A.sup.2 and A.sup.3 is a monocyclic divalent aromatic radical and Y
is a single bond or a bridging radical in which one or two atoms
separate A.sup.2 from A.sup.3.
3. The copolyestercarbonate according to claim 2 wherein the
carbonate structural units are bisphenol A carbonate units.
4. The copolyestercarbonate according to claim 1 wherein the dimer
acid composition is hydrogenated.
5. The copolyestercarbonate according to claim 1 wherein the ester
units are derived from at least one acid having one of the
following formulas or a hydrogenated analog thereof: 4
6. The copolyestercarbonate according to claim 5 which comprises
ester units derived from an acid of formula IX.
7. The copolyestercarbonate according to claim 1 wherein the dimer
acid composition has the CAS registry number 68783-41-5.
8. The copolyestercarbonate according to claim 1 wherein the dimer
acid composition has the CAS registry number 61788-89-4.
9. The copolyestercarbonate according to claim 1 which has a weight
average molecular weight, as determined by gel permeation
chromatography, in the range of about 5,000-100,000.
10. The copolyestercarbonate according to claim 1 wherein the
proportion of ester units is in the range of about 0.5-25 mole
percent.
11. A copolyestercarbonate comprising bisphenol A carbonate
structural units and ester units derived from bisphenol A and a
composition comprising at least one C.sub.36 dimer acid having the
CAS registry number 68783-41-5, said ester units being present in
the range of about 0.5-25 mole percent.
12. A copolyestercarbonate comprising bisphenol A carbonate
structural units and ester units derived from bisphenol A and a
composition comprising at least one C.sub.36 dimer acid having the
CAS registry number 61788-89-4, said ester units being present in
the range of about 0.5-25 mole percent.
13. A method for preparing a copolyestercarbonate which comprises
passing phosgene through a mixture, in a two-phase aqueous-organic
medium, of at least one dihydroxyaromatic compound, a composition
comprising at least one C.sub.36 dimer acid and at least one
aliphatic tertiary amine, or phase transfer catalyst or mixture
thereof, while maintaining the pH of the aqueous phase of said
mixture in the range of about 9-11 by addition of aqueous alkali as
necessary.
14. The method according to claim 13 wherein the organic medium
comprises a chlorinated aliphatic hydrocarbon.
15. The method according to claim 14 wherein the chlorinated
aliphatic hydrocarbon is methylene chloride.
16. The method according to claim 13 wherein A.sup.1 has the
formula --A.sup.2--Y--A.sup.3--, (II)wherein each of A.sup.2 and
A.sup.3 is a monocyclic divalent aromatic radical and Y is a single
bond or a bridging radical in which one or two atoms separate
A.sup.2 from A.sup.3.
17. The method according to claim 16 wherein the dihydroxyaromatic
compound is bisphenol A.
18. The method according to claim 13 wherein the dimer acid
composition is hydrogenated.
19. The method according to claim 13 wherein the dimer acid
composition comprises at least one acid having one of the following
formulas or a hydrogenated analog thereof: 5
20. The method according to claim 19 wherein the dimer acid
composition comprises the acid of formula IX.
21. The method according to claim 13 wherein the dimer acid
composition has the CAS registry number 68783-41-5.
22. The method according to claim 13 wherein the dimer acid
composition has the CAS registry number 61788-89-4.
23. The method according to claim 13 wherein the proportion of
dimer acid composition is in the range of about 0.5-25 mole
percent, based on the total of dihydroxyaromatic compound and dimer
acid.
24. The method according to claim 13 wherein an aliphatic tertiary
amine is employed.
25. The method according to claim 24 wherein the tertiary amine is
triethylamine.
26. The method according to claim 13 wherein the alkali is sodium
hydroxide.
27. The method according to claim 13 wherein the reaction
temperature is in the range of about 10-50.degree. C.
28. The method according to claim 13 wherein the pH is initially
maintained in the range of about 9.0-10.0 and is raised to a higher
value up to about 10.5 after about 60-75% by weight of the total
phosgene has been introduced.
29. A method for preparing a copolyestercarbonate which comprises
passing phosgene through a mixture, in a two-phase aqueous-organic
medium comprising water and methylene chloride, of bisphenol A, a
composition comprising at least one C.sub.36 dimer acid having the
CAS registry number 68783-41-5 and triethylamine, while adding
aqueous alkali to maintain the pH of the aqueous phase of said
mixture in the range of about 9.0-10.0 in initial stages of the
reaction and at a higher value up to about 10.5 after about 60-75%
by weight of the total phosgene has been introduced.
30. A method for preparing a copolyestercarbonate which comprises
passing phosgene through a mixture, in a two-phase aqueous-organic
medium comprising water and methylene chloride, of bisphenol A, a
composition comprising at least one C.sub.36 dimer acid having the
CAS registry number 61788-89-4 and triethylamine, while adding
aqueous alkali to maintain the pH of the aqueous phase of said
mixture in the range of about 9.0-10.0 in initial stages of the
reaction and at a higher value up to about 10.5 after about 60-75%
by weight of the total phosgene has been introduced.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to copolyestercarbonates, and more
particularly to polyestercarbonates containing a novel
ester-derived unit.
[0002] Copolyestercarbonates may be prepared by the interfacially
conducted condensation of dihydroxyaromatic compounds with
dicarboxylic acids and phosgene in an immiscible aqueous-organic
medium. The reaction ordinarily takes place in the presence of a
tertiary amine, a phase transfer catalyst or both. They may also be
prepared by a transesterification reaction between a diaryl
carbonate such as diphenyl carbonate and a mixture of at least one
dihydroxyaromatic compound and at least one aryl ester of a
dicarboxylic acid. The product copolyestercarbonates have
properties similar to those of polycarbonates but are generally
more ductile, especially when the ester units are "soft block"
units derived from aliphatic acids.
[0003] A class of widely used commercially available
copolyestercarbonates comprises carbonate structural units derived
from 2,2-bis(4-hydroxyphenyl- )propane, hereinafter "bisphenol A",
and ester units derived from a dicarboxylic acid containing at
least 10 carbon atoms, particularly dodecanedioic acid (hereinafter
"DDDA"). In order to effect complete incorporation of ester units
in the copolymer, it is typically necessary to maintain the pH of
an interfacial reaction mixture in the range of about 8.0-8.5 while
dicarboxylic acid monomer is present therein. After all the acid
has been incorporated, the pH is typically increased to a value in
the range of about 9.0-10.5. The higher pH permits better pH
control and minimizes the occurrence of such problems as phosgene
buildup in the reactor and production of carbon dioxide by
hydrolysis of carbonate salts, which can result in pressure buildup
in the reactor.
[0004] For simplicity of operation, it would be desirable to employ
a dicarboxylic acid which could be fully incorporated in the
copolyestercarbonate at the same pH advantageously employed for
incorporation of carbonate units; i.e., one in the range of about
9.0-10.5. This would permit conversion of a homopolycarbonate
production system to copolyestercarbonate production with little or
no change in procedure.
[0005] It is also sometimes found that the use of DDDA affords a
polymer which is difficult to isolate, as by precipitation. The
particles tend to stick together, forming lumps and making
precipitation very cumbersome and complicated. This is particularly
true at low molecular weights; for example, at weight average
molecular weights (determined, for the most part, by gel permeation
chromatography) below about 20,000.
[0006] Polymer mixtures comprising conventional polycarbonates or
copolyestercarbonates and various branched dimeric fatty
acid-derived polyesters are disclosed in U.S. Pat. No. 5,635,560.
However, the fatty acid precursors therefor are described as
containing phenolic OH groups. Moreover, there is no disclosure of
copolyestercarbonates containing units derived from such fatty
acids.
SUMMARY OF THE INVENTION
[0007] The present invention provides copolyestercarbonates having
excellent physical properties. Said copolyestercarbonates may be
produced by a relatively simple interfacial polymerization method,
at a pH level within a single range for the entire reaction. The
resulting copolyestercarbonates have properties which are equal to
or, at certain molecular weight levels, superior to those of
corresponding polymers prepared using DDDA.
[0008] One aspect of the invention is copolyestercarbonates
comprising carbonate structural units of the formula 1
[0009] wherein each A.sup.1 is independently a divalent aliphatic,
alicyclic or aromatic radical, and ester units derived from a
dihydroxyaromatic compound of the formula A.sup.1(OH).sub.2 and a
composition comprising at least one C.sub.36 dimer acid.
[0010] Another aspect of the invention is a method for preparing a
copolyestercarbonate which comprises passing phosgene through a
mixture, in a two-phase aqueous-organic medium, of at least one
dihydroxyaromatic compound, a composition comprising at least one
C.sub.36 dimer acid and at least one aliphatic tertiary amine, or
phase transfer catalyst or mixture thereof, while maintaining the
pH of the aqueous phase of said mixture in the range of about 9-11
by addition of aqueous alkali as necessary.
DETAILED DESCRIPTION; PREFERRED EMBODIMENTS
[0011] The copolyestercarbonates of the invention are characterized
in part by the presence of carbonate structural units of formula I,
in which A.sup.1 may be a divalent aliphatic, alicyclic or aromatic
radical or a mixture thereof. It is most often an aromatic radical,
which may be an aromatic hydrocarbon or a substituted aromatic
hydrocarbon radical, with illustrative substituents being alkyl,
cycloalkyl, alkenyl (e.g., crosslinkable-graftable moieties such as
allyl), halo (especially fluoro, chloro and/or bromo), nitro and
alkoxy.
[0012] The preferred A.sup.1 values have the formula
--A.sup.2--Y--A.sup.3--, (II)
[0013] wherein each of A.sup.2 and A.sup.3 is a monocyclic divalent
aromatic radical and Y is a single bond or a bridging radical in
which one or two atoms separate A.sup.2 from A.sup.3. The free
valence bonds in formula II are usually in the meta or para
positions of A.sup.2 and A.sup.3 in relation to Y.
[0014] In formula II, the A.sup.2 and A.sup.3 values may be
unsubstituted phenylene or substituted derivatives thereof wherein
the substituents are as defined for A.sup.1. Unsubstituted
phenylene radicals are preferred, but it is also contemplated to
employ, for example, polymers in which each of A.sup.2 and A.sup.3
has two methyl substituents in ortho positions to the free valence
bond. Both A.sup.2 and A.sup.3 are preferably p-phenylene, although
both may be o- or m-phenylene or one o- or m-phenylene and the
other p-phenylene.
[0015] The bridging radical, Y, is one in which one or two atoms,
preferably one, separate A.sup.2 from A.sup.3. It is most often a
hydrocarbon radical and particularly a saturated C.sub.1-12
aliphatic or alicyclic radical. Illustrative radicals are
methylene, cyclohexylmethylene, [2.2.1]bicycloheptylmethylene,
ethylene, ethylidene, 2,2-propylidene,
1,1-(2,2-dimethylpropylidene), phenylethylidene, cyclohexylidene,
3,3,5-trimethylcyclohexylidene, cyclopentadecylidene,
cyclododecylidene, 9,9-fluorenylidene and 2,2-adamantylidene,
especially an alkylidene radical. Aryl-substituted radicals are
included, as are unsaturated radicals and radicals containing atoms
other than carbon and hydrogen; e.g., oxy groups. Substituents such
as those previously enumerated may be present on the aliphatic,
alicyclic and aromatic portions of the Y group.
[0016] For most purposes, the preferred units containing moieties
of formula II are those in which each of A.sup.2 and A.sup.3 is
p-phenylene and Y is isopropylidene; i.e., those derived from
bisphenol A. Such units may be present in combination with other
units of formula II or formula I.
[0017] Also present in the copolyestercarbonates of this invention
are ester units derived from a dihydroxyaromatic compound of the
formula A.sup.1(OH).sub.2 and a composition comprising at least one
C.sub.36 dimer acid. Dimer acid compositions are known in the art;
reference is made, for example, to Kirk-Othmer Encyclopedia of
Chemical Technology, Fourth Edition, 8, 223. They typically
comprise principally dimers of C.sub.18 unsaturated fatty acids
such as oleic acid (cis-9-octadecenoic acid), elaidic acid
(trans-9-octadecenoic acid), linoleic acid
(cis-9-cis-12-octadecadienoic acid) or mixtures thereof,
particularly naturally occurring mixtures such as tall oil fatty
acids. The use of hydrogenated dimer acids is within the scope of
the invention, and is often preferred.
[0018] The molecular structures of the acids present in dimer acid
compositions (non-hydrogenated and hydrogenated) vary with the
starting materials employed. They may include the following and
their hydrogenated analogs: 2
[0019] Use of any dimer acid compositions comprising compounds of
formulas III-IX or their hydrogenated analogs is particularly
contemplated as part of the invention. Dimer acids are also
identified by the CAS registry numbers 61788-89-4 and 68783-41-5,
and any composition to which these numbers apply is useful
according to the invention. It is further contemplated to employ
dimer acid compositions in combination with other aliphatic
dicarboxylic acids, such as DDDA.
[0020] In a preferred embodiment of the present invention the
copolyestercarbonate is substantially linear. Many dimer acid
compositions also contain minor proportions of C.sub.54 trimer
acids, which are tricarboxylic acids. To prepare substantially
linear copolyestercarbonates, the level of trimer acids is
preferably as low as possible since they may react to produce some
minor proportion of branched polymer. If they are present, the
level of trimer acids is preferably less than about 2%, more
preferably less than about 1%.
[0021] The preferred composition for use according to the
invention, in many instances, is a hydrogenated product
commercially available from Unichema under the trade name PRIPOL
1009. It comprises about 98.5% by weight dimer acid, about 1%
trimer acid and about 0.1% monocarboxylic acids, and particularly
comprises the compound of formula IX. Cognis Corporation also
provides dimer acid compositions which may be used, including some
that are essentially identical to the products available from
Unichema.
[0022] In one embodiment of the method of this invention, a
two-phase aqueous-organic system containing at least one
dihydroxyaromatic compound and the dimer acid composition is
phosgenated. Water-immiscible organic solvents which may be
employed as the organic constituent of the two-phase system include
chlorinated aliphatic hydrocarbons, such as methylene chloride,
chloroform, dichloroethane, trichloroethane, tetrachloroethane,
dichloropropane and 1,2-dichloroethylene, and substituted aromatic
hydrocarbons such as chlorobenzene, o-dichlorobenzene and the
various chlorotoluenes. The chlorinated aliphatic hydrocarbons are
preferred, with methylene chloride being most preferred.
[0023] Phosgenation may be conducted according to art-recognized
interfacial procedures, employing a suitable interfacial
polymerization catalyst which may be an aliphatic tertiary amine
such as triethylamine, a heterocyclic tertiary amine such as
4-dimethylaminopyridine, or a phase transfer catalyst such as a
tetraalkylammonium halide, a tetraalkylphosphonium halide or a
hexaalkylguanidinium halide. Also present is an alkaline reagent,
preferably sodium hydroxide, and optionally a chain termination
agent such as phenol or p-cumylphenol.
[0024] The pH of the aqueous phase of the reaction mixture is
maintained in the range of about 9.0-11, preferably about 9.0-10.5.
More preferably, it is in the range of about 9.0-10.0 in initial
stages and is then raised to a higher value up to about 10.5,
typically after about 60-75% by weight of the total phosgene has
been introduced. At early stage values above about 10.0, there is
an increased tendency toward the formation of anhydrides from the
dimer acid, which can degrade stability of the
copolyestercarbonate.
[0025] In the interfacial reaction mixture, the volume ratio of
organic liquid to water is generally in the range of about 1-3:1.
The proportions of dimer acid are most often in the ranges of about
0.5-25 mole percent and preferably about 1-10 mole percent, based
on the total of dihydroxyaromatic compound and dimer acid. The
proportions of catalyst are most often in the ranges of about 1-10
mole percent, preferably about 1.5-5 mole percent, and more
preferably about 1.5-3 mole percent, based on the total of
dihydroxyaromatic compound and dimer acid. The proportions of chain
termination agent (when employed) are most often in the ranges of
about 0.5-6.0 mole percent, based on the total of dihydroxyaromatic
compound and dimer acid. Since the dihydroxyaromatic compound and
dimer acid composition are incorporated in the polymer in
substantially stoichiometric quantities, the proportion of ester
units in the copolyestercarbonate of the invention is also usually
in the range of about 0.5-25 mole percent. The total molar ratio of
phosgene to total dihydroxyaromatic compound and dimer acid is most
often in the range of about 1.05-1.5. Typical reaction temperatures
are in the range of about 10-50.degree. C., preferably about
25-40.degree. C.
[0026] Following interfacial preparation, the copolyestercarbonate
is present in the organic phase and may be worked up by
conventional methods. These may include such operations as washing
and isolation by non-solvent precipitation, steam precipitation or
boiling water precipitation.
[0027] The copolyestercarbonates of the invention may also be
prepared by a transesterification (melt) procedure. Such a
procedure employs a dialkyl carbonate such as diphenyl carbonate, a
dihydroxyaromatic compound and an ester, most often a phenyl ester,
of the dimer acid composition.
[0028] Typical weight average molecular weights, as determined by
gel permeation chromatography, for the copolyestercarbonates of the
invention are in the range of about 5,000-100,000, and preferably
about 15,000-50,000.
[0029] The preparation of copolyestercarbonates by the method of
the invention is illustrated by the following non-limiting
examples
EXAMPLES 1-3
[0030] In each example, a 500 milliliter (ml) Morton flask was
charged with 29.4 grams (g) (130 millimoles [mmol]) of bisphenol A,
7.92 g (14.3 mmol, 10 mole percent based on total bisphenol A and
dimer acid) of PRIPOL 1009 dimer acid, 1.37 g (6.5 mmol) of
p-cumylphenol, 120 ml of methylene chloride, 67 ml of distilled
water and 360 microliters (.mu.l) of triethylamine. Sodium
hydroxide (50% by weight aqueous), 2.5 g, was added and the mixture
was stirred for 3 minutes. Phosgene, 10.12 g (10.12 mmol), was
introduced at a rate of 0.5 g/min while the pH of the aqueous phase
was maintained at a set value by addition of sodium hydroxide
solution as necessary. When addition of this portion of phosgene
was complete, the pH was raised to 10.5 over 3 minutes and an
additional 7.20 g of phosgene (total 163.8 mmol) was introduced at
the same rate. The organic phase was separated and washed with
aqueous hydrochloric acid and distilled water. The desired
copolyestercarbonate was precipitated by pouring the solution into
750 ml of boiling water, washed with water and vacuum dried
overnight. It was analyzed by proton nuclear magnetic resonance
spectroscopy to determine the level of acid incorporation and the
proportion of anhydride groups.
[0031] The results are given in Table I, in comparison with
Controls 1-12 in which the dimer acid was replaced by sebacic acid
("C.sub.10"), DDDA ("C.sub.12"), hexadecanedioic acid ("C.sub.16")
and stearic acid ("C.sub.18").
1TABLE I Diacid incorporation, Anhydride, Example Diacid pH mole %
% 1 Dimer acid 9.5 10.0 0 2 Dimer acid 10.0 10.0 0 3 Dimer acid
10.5 10.0 17.5 Control 1 C.sub.10 7.5 9.99 0 Control 2 C.sub.10 8.0
9.56 Trace Control 3 C.sub.10 8.5 7.57 11.0 Control 4 C.sub.10 9.0
6.07 33.0 Control 5 C.sub.12 8.0 9.86 0 Control 6 C.sub.12 8.5 9.85
0 Control 7 C.sub.12 9.0 9.60 18.0 Control 8 C.sub.16 8.0 9.94 0
Control 9 C.sub.16 8.5 10.0 0 Control 10 C.sub.16 9.0 10.0 0
Control 11 C.sub.16 9.5 9.51 7.8 Control 12 C.sub.18 9.5 8.1
18.0
[0032] A comparison of Examples 1-3 with the controls demonstrates
that with the use of dimer acid, it is possible to perform the
initial stage of the phosgenation at a pH of at least 9.5 without
loss of ester units from the polymer. The same is not true of the
lower dicarboxylic acids, many of which are not completely
incorporated even at a pH as low as 9.0. It is also apparent that a
final pH of 10.5 results in a substantial proportion of anhydride
linkages in the polymer.
EXAMPLES 4-6
[0033] In each example a 1,136 liter stirred reactor was charged
with 189 liters of deionized water, 220 liters of methylene
chloride, 90.7 kilograms of bisphenol A, 160 g of sodium gluconate
(used as a sequestering agent for iron), 1064 ml of triethylamine
and various proportions of p-cumylphenol (to produce polymers of
targeted weight average molecular weight) and dimer acid. After the
addition, the monomer feed tank was rinsed with an additional 76
liters of methylene chloride. Aqueous sodium hydroxide solution
(50% by weight), 3.8 liters, was added to the reactor and the
contents were allowed to equilibrate for 5 minutes; the agitator
was set to 85 rpm. Upon completion of the equilibration step, the
reaction mixture was phosgenated sequentially (ramp) at rates of
90.7, 136.1 and 56.7 kg/min for 5, 15 and 25 minutes, respectively.
After the phosgenation was complete, the reaction mixture was
checked for free bisphenol A; if any was detected, the mixture was
rephosgenated with 0.45-0.91 kg phosgene and retested. The mixture
was then sent to a centrifuge work-up tank at pH 9-10, washed and
precipitated substantially as described for Examples 1-3. The
precipitation behavior of each product was evaluated.
[0034] The results are given in Table II, in comparison with
Controls 13-15 in which the dimer acid was replaced by DDDA.
2TABLE II p- Targeted mol. Cumylphenol, Dicarboxylic Precipitation
Example wt. kg acid, mole % behavior 4 17,500 5.44 3.4 Excellent 5
22,500 4.35 3.4 Excellent 6 28,500 2.81 3.4 Excellent Control 13
17,500 5.44 4.3 Difficult to precipitate Control 14 22,500 4.35 4.3
Erratic: lumps, sticking Control 15 28,500 2.81 4.3 Excellent
[0035] It can be seen that the use of dimer acid affords
copolyestercarbonates comparable, in general, to the use of DDDA
but exhibiting better precipitation behavior. This difference in
response to precipitation is not, so far as can be determined, a
result of the variation in proportion of ester units.
[0036] While typical embodiments have been set forth for the
purpose of illustration, the foregoing descriptions and examples
should not be deemed to be a limitation on the scope of the
invention. Accordingly, various modifications, adaptations, and
alternatives may occur to one skilled in the art without departing
from the spirit and scope of the present invention.
* * * * *