U.S. patent application number 09/771704 was filed with the patent office on 2001-08-16 for ethylenimine polymer, aqueous solution of ethylenimine polymer, production process for the same and purifying process therefor.
This patent application is currently assigned to NIPPON SHOKUBAI CO., LTD.. Invention is credited to Onda, Yoshiyuki, Satoh, Isao, Suzuki, Seiichi.
Application Number | 20010014730 09/771704 |
Document ID | / |
Family ID | 27481000 |
Filed Date | 2001-08-16 |
United States Patent
Application |
20010014730 |
Kind Code |
A1 |
Suzuki, Seiichi ; et
al. |
August 16, 2001 |
Ethylenimine polymer, aqueous solution of ethylenimine polymer,
production process for the same and purifying process therefor
Abstract
Provided are processes by which an ethylenimine polymer and an
aqueous solution thereof can advantageously be produced at low
costs in an industrial scale. The ethylenimine polymer can be
produced by polymerizing crude ethylenimine obtained by a simple
distilling operation from an ethylenimine-containing reaction
mixture produced by subjecting ethanolamine to intermolecular
dehydration reaction, preferably crude ethylenimine having impurity
contents which are controlled in the specific ranges. When the
above crude ethylenimine is polymerized in an aqueous medium,
capable of being obtained is an aqueous solution of an ethylenimine
polymer having a higher molecular weight than that produced by
non-solvent polymerization. The ethylenimine polymer can be
purified by, for example, adding water thereto, mixing them and
then vaporizing and removing water under heating. The aqueous
solution of an ethylenimine polymer can be purified by heating and
condensing it.
Inventors: |
Suzuki, Seiichi;
(Yokohama-shi, JP) ; Onda, Yoshiyuki; (Tokyo,
JP) ; Satoh, Isao; (Yokohama-shi, JP) |
Correspondence
Address: |
SHERMAN & SHALLOWAY
413 North Washington Street
Alexandria
VA
22314
US
|
Assignee: |
NIPPON SHOKUBAI CO., LTD.
|
Family ID: |
27481000 |
Appl. No.: |
09/771704 |
Filed: |
January 30, 2001 |
Current U.S.
Class: |
528/424 ;
210/767; 210/774; 524/800; 528/483; 528/499; 528/500; 528/501 |
Current CPC
Class: |
C08G 73/0213
20130101 |
Class at
Publication: |
528/424 ;
528/483; 528/499; 528/500; 528/501; 524/800; 210/767; 210/774 |
International
Class: |
C08G 073/02; C08G
073/00; B01D 003/00; B01D 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 3, 2000 |
JP |
2000-26569 |
Feb 3, 2000 |
JP |
2000-26572 |
Mar 24, 2000 |
JP |
2000-83303 |
Mar 27, 2000 |
JP |
2000-85781 |
Claims
1. An ethylenimine polymer characterized by being produced by
polymerizing crude ethylenimine obtained by intermolecular
dehydration reaction of monoethanolamine in the presence of a
catalyst.
2. The ethylenimine polymer as described in claim 1, wherein the
above crude ethylenimine contains at least 90% by weight of
ethylenimine, and as impurities, less than 1000 ppm (by weight) of
monoethanolamine, less than 2% by weight in total of lower amines
comprising ammonia, methylamine and ethylamine, less than 2% by
weight of acetonitrile and less than 1000 ppm (by weight) of
water.
3. A production process for the ethylenimine polymer as described
in claim 1 or 2, comprising subjecting monoethanolamine to
intermolecular dehydration reaction in the presence of a catalyst
to produce crude ethylenimine and then polymerizing this crude
ethylenimine.
4. A process for purifying the ethylenimine polymer produced by the
process as described in claim 3, characterized by: (A) bubbling
inert gas into the above ethylenimine polymer, (B) adding water to
the ethylenimine polymer, mixing them and then vaporizing and
removing water under heating, or (C) adding water to the
ethylenimine polymer, mixing them and then vaporizing and removing
water by heating while bubbling inert gas into the ethylenimine
polymer.
5. An ethylenimine polymer aqueous solution characterized by being
produced by polymerizing in an aqueous medium, crude ethylenimine
obtained by intermolecular dehydration reaction of monoethanolamine
in the presence of a catalyst.
6. The ethylenimine polymer aqueous solution as described in claim
5, wherein the above crude ethylenimine contains at least 90% by
weight of ethylenimine, and as impurities, less than 1000 ppm (by
weight) of monoethanolamine, less than 2% by weight in total of
lower amines comprising ammonia, methylamine and ethylamine, less
than 2% by weight of acetonitrile and less than 1000 ppm (by
weight) of water.
7. A production process for the ethylenimine polymer aqueous
solution as described in claim 5 or 6, comprising subjecting
monoethanolamine to intermolecular dehydration reaction in the
presence of a catalyst to produce crude ethylenimine and then
polymerizing this crude ethylenimine in an aqueous medium.
8. A process for purifying the ethylenimine polymer aqueous
solution produced by the process as described in claim 7,
characterized by heating and condensing the above aqueous solution.
Description
[0001] The present invention relates to an ethylenimine polymer, an
aqueous solution of an ethylenimine polymer, a production process
for the same and a purifying process therefor.
[0002] It is publicly known that monoethanolamine is subjected to
intermolecular dehydration reaction in the presence of a catalyst
to obtain ethylenimine. Known as the catalyst are, for example,
tantalum base catalysts (U.S. Pat. No. 4,289,656, 4,337,175 and
4,477,591), silicon-alkaline metal and/or alkaline earth metal base
catalysts (Japanese Patent Publications No. 13699/1993 and
13700/1993), phosphorus-alkaline metal and/or alkaline earth metal
base catalysts (Japanese Patent Publications No. 76344/1993,
87301/1993, 76343/1993, 55498/1993 and 16905/1993), and catalysts
prepared by carrying these silicon/phosphorus-alkaline
metal/alkaline earth metal base catalyst compositions on molded
ceramic carriers (Japanese Patents Laid-Opens No. 132564/1997 and
194455/1997).
[0003] A part of these catalysts is used for producing ethylenimine
in an industrial scale, and an ethylenimine-containing reaction
mixture obtained in this reaction is purified through a high degree
purifying step and then used for synthesizing various ethylenimine
polymers. To be specific, contained in an ethylenimine-containing
reaction mixture obtained by intermolecular dehydration reaction of
monoethanolamine are, in addition to intended ethylenimine,
unreacted monoethanolamine; oligomers of ethylenimine; aldehydes
such as acetaldehyde; heavy impurities such as a Schiff base
produced by a reaction of acetaldehyde with monoethanolamine of the
raw material; lower amines such as ammonia, methylamine and
ethylamine; and acetonitrile. Accordingly, it is recognized that
these impurities have to be removed from the above
ethylenimine-containing reaction mixture through a high degree
purifying step in order to obtain purified ethylenimine which can
be used for polymerization reaction.
[0004] In conventional techniques, ethylenimine which is purified
to such a high degree and therefore is expensive has to be used to
produce an ethylenimine polymer, so that the production cost
thereof can not be avoided from going up, and they are not
necessarily industrially advantageous.
[0005] Accordingly, an object of the present invention is to
provide an ethylenimine polymer which solves the problems described
above on the conventional techniques and which is decreased in a
production cost and industrially advantageous, and a production
process for the same.
[0006] The present inventors have found that an ethylenimine
polymer having a performance which is entirely equivalent to those
of conventional ethylenimine polymers obtained by using purified
ethylenimine for a raw material can be produced by polymerizing
crude ethylenimine obtained by a simple distilling operation from
an ethylenimine-containing reaction mixture produced by subjecting
ethanolamine to intermolecular dehydration reaction, particularly
crude ethylenimine having impurity contents which are controlled in
specific ranges, and they have come to complete the present
invention based on this knowledge.
[0007] Thus, according to the present invention, provided is an
ethylenimine polymer characterized by being produced by
polymerizing crude ethylenimine obtained by intermolecular
dehydration reaction of monoethanolamine in the presence of a
catalyst.
[0008] Further, according to the present invention, provided is a
production process for an ethylenimine polymer characterized by
subjecting monoethanolamine to intermolecular dehydration reaction
in the presence of a catalyst to produce crude ethylenimine and
then polymerizing this crude ethylenimine.
[0009] A process itself for producing an ethylenimine polymer by
subjecting monoethanolamine to intermolecular dehydration reaction
in the presence of a catalyst to produce an ethylenimine-containing
reaction mixture shall not specifically be restricted and can be
carried out by a usually well known process. To be specific,
vaporized monoethanolamine is introduced into a catalyst layer as a
raw material gas, if necessary, after suitably diluting this with
inert gas such as nitrogen or after adding thereto ammonia, steam
or hydrogen for the purpose to inhibit side reactions. The reaction
pressure may be any of atmospheric pressure, reduced pressure and
elevated pressure. The reaction temperature falls usually in a
range of 300 to 500.degree. C. A space velocity of the raw material
gas is varied depending on a concentration of monoethanolamine and
the kind of the catalyst used and therefore can not absolutely be
specified, and it falls usually in a range of 50 to 5000 h.sup.-1.
The catalyst to be used shall not specifically be restricted as
well, and the catalysts described in the above patent publications
can be used. Among them, suitably used are catalysts described in
Japanese Patent Publications No. 13699/1993, 13700/1993,
76344/1993, 87301/1993, 76343/1993, 55498/1993 and 16905/1993.
[0010] The ethylenimine-containing reaction mixture obtained by the
gas phase intermolecular dehydration reaction described above is
collected by means of a scavenger or condensed as it is and
collected. An amine compound is suited as the scavenger, and
particularly monoethanolamine is the most preferable since it is
also the raw material. Mainly ethylenimine, unreacted
monoethanolamine and moisture are contained in the
ethylenimine-containing reaction mixture. Contained as by-products
are lower amines such as ammonia, methylamine and ethylamine;
acetonitrile; aldehydes such as acetaldehyde; Schiff bases produced
by a reaction of acetaldehyde with monoethanolamine which is the
raw material.
[0011] In the present invention, preferably produced is an
ethylenimine polymer by polymerizing crude ethylenimine which is
obtained by subjecting the ethylenimine-containing reaction mixture
described above to a simple distilling operation and in which
impurity contents are controlled in specific ranges. Such crude
ethylenimine contains, for example, 90% by weight or more,
preferably 95 to 99.9% by weight of ethylenimine, and as
impurities, less than 1000 ppm (by weight), preferably less than
500 ppm of monoethanolamine, less than 2% by weight, preferably
less than 1% by weight in total of lower amines comprising ammonia,
methylamine and ethylamine, less than 2% by weight, preferably less
than 1% by weight of acetonitrile and less than 1000 ppm (by
weight) of water.
[0012] In addition to the above, the ethylenimine-containing
reaction mixture is brought into contact with an organic solvent
such as toluene and xylene to extract heavy matters contained in
the reaction mixture, whereby such crude ethylenimine as described
above can be obtained as well.
[0013] Crude ethylenimine having an ethylenimine content of smaller
than 90% by weight and impurity contents exceeding the ranges
described above causes the problem that an ethylenimine polymer
obtained by polymerization thereof is inferior in performances, and
therefore it is not preferred in the present invention.
[0014] In the present invention, such crude ethylenimine as
described above is recovered from the ethylenimine-containing
reaction mixture by a simple distilling operation or extracting
operation, and then this crude ethylenimine is polymerized to
produce an ethylenimine polymer.
[0015] A process for producing an ethylenimine polymer using crude
ethylenimine shall not specifically be restricted, and it can be
produced by a process usually used for producing an ethylenimine
polymer. The polymerization catalyst and the polymerization
conditions can suitably be selected from those usually used for
polymerizing ethylenimine. For example, crude ethylenimine can be
reacted in the presence of an effective amount of an acid catalyst,
for example, hydrochloric acid at 0 to 200.degree. C. (Japanese
Patent Publication No. 33120/1074, Japanese Patent Publication
(through PCT) No. 501757/2000 and the like). Further, crude
ethylenimine may be addition-polymerized on the basis of an
ethylenimine polymer. The ethylenimine polymer of the present
invention includes an ethylenimine homopolymer and a copolymer of
ethylenimine with a compound copolymerizable with ethylenimine, for
example, amines. A production process for such ethylenimine
polymers can be referred to Japanese Patent Publications No.
8828/1968 and 33120/1974.
[0016] The reaction system may be any of a batch system, a
semi-batch system and a continuous flow system. In the case of a
batch system, the polymer is increased in a viscosity in producing
the polymer, and therefore a stirring blade for high viscosity, for
example, a max blend blade (manufactured by Sumitomo Heavy Machine
Ind. Co., Ltd.) is suitably used for heat removal, dispersion and
acceleration of the reaction. Further, in order to make heat
removal efficient, ethylenimine is suitably polymerized under
refluxing of ethylenimine by means of a vertical tube type
condenser.
[0017] Lower amines such as ammonia, methylamine and ethylamine and
acetonitrile remain in a certain case in the ethylenimine polymer
of the present invention obtained by polymerizing in the manner
described above. These impurities exert adverse effects (generation
of an offensive smell and a reduction in the stability) to a
quality of the ethylenimine polymer and therefore are preferably
removed as much as possible by a suitable purifying process.
[0018] Further, according to the present invention, such purifying
process is provided as well. It is a process characterized by
processing the ethylenimine polymer obtained by polymerizing crude
ethylenimine by any of the following operations (A), (B) and (C),
and the high purity ethylenimine polymer which meets a quality
standard industrially required can be obtained by this process:
[0019] A: bubbling inert gas into the ethylenimine polymer B:
adding water to the ethylenimine polymer, mixing them and then
vaporizing and removing water under heating C: adding water to the
ethylenimine polymer, mixing them and then vaporizing and removing
water by heating while bubbling inert gas into the ethylenimine
polymer.
[0020] The operation (A) comprises bubbling inert gas into the
ethylenimine polymer. To be specific, inert gas is bubbled into the
ethylenimine polymer in the reactor after finishing the
polymerization reaction. Used as the inert gas is gas which is
inert to amines, such as nitrogen gas, helium gas and argon gas,
and nitrogen gas is suitably used from an economical point of view.
A temperature of the polymer in bubbling does not have to exceed
200.degree. C. and is held preferably in a range of 100 to
180.degree. C. An amount of the inert gas is usually 0.01 to 10
Nl/min, preferably 0.1 to 2 Nl/min. The bubbling time is usually
0.5 to 100 hours, preferably 1 to 20 hours. The operation may be
carried out either at atmospheric pressure or under reduced
pressure, and when it is carried out under reduced pressure, the
preferred pressure in the reactor is 10 to 700 mm Hg. The operation
(A) provides the high-purity ethylenimine polymer in which all
contents (B) of lower amines and acetonitrile are less than 1
ppm.
[0021] The operation (B) comprises adding water to the ethyleni-
mine polymer, mixing them and then vaporizing and removing water
under heating. To be specific, after finishing the polymerization
reaction, water is added to the polymer in the reactor and mixed
well, and then this mixture is heated to vaporize and remove water.
An addition amount of water is usually 1 to 95%by weight,
preferably 5 to 30% by weight based on the polymer. In vaporizing
and removing water, a temperature of the polymer does not have to
exceed 200.degree. C. and is held preferably in a range of 100 to
150.degree. C. The operation may be carried out either at
atmospheric pressure or under reduced pressure, and when it is
carried out under reduced pressure, the preferred pressure in the
reactor is 10 to 700 mm Hg. The high-purity ethylenimine polymer in
which all contents of lower amines and acetonitrile are less than 1
ppm is obtained by vaporizing and removing 15% by weight or more of
water added.
[0022] The operation (C) comprises a combination of the operation
(A) and the operation (B), and this can provide the high-purity
ethylenimine polymer by shorter operating time. To be specific,
after finishing the polymerization reaction, water is added to the
polymer, and water is vaporized and removed from this mixture under
heating while bubbling inert gas into this mixture.
[0023] The ethylenimine polymer obtained by subjecting ethylenimine
to non-solvent polymerization in the presence of an acid catalyst
has been described above. In the non-solvent polymerization method,
however, it is difficult to obtain a polymer having a high
molecular weight because of a problem on a viscosity. Accordingly,
desired is a process for producing an ethylenimine polymer having a
higher molecular weight. Proposed as one of such processes is a
process for producing an aqueous solution of an ethylenimine
polymer having a high molecular weight by polymerizing highly
purified ethylenimine in an aqueous medium (Japanese Patent
Publication No. 8828/1968). However, this process requires a high
degree purifying step of ethylenimine and therefore can not be
avoided from increasing in a production cost, so that it is not
necessarily industrially advantageous.
[0024] The present inventors have found that the aqueous solution
of the high molecular weight ethylenimine polymer having a
performance which is entirely equivalent to those of conventional
aqueous solutions of ethylenimine polymers obtained by polymerizing
purified ethylenimine in an aqueous medium can be produced by
polymerizing in an aqueous medium, crude ethylenimine obtained by a
simple distilling operation from the ethylenimine-containing
reaction mixture produced by subjecting ethanolamine to
intermolecular dehydration reaction in the presence of a catalyst,
particularly crude ethylenimine having impurity contents which are
controlled in the specific ranges described above.
[0025] Thus, according to the present invention, provided is the
aqueous solution of the ethylenimine polymer characterized by being
produced by polymerizing in an aqueous medium, crude ethylenimine
obtained by intermolecular dehydration reaction of monoethanolamine
in the presence of a catalyst.
[0026] Further, according to the present invention, provided is a
production process for an aqueous solution of an ethylenimine
polymer characterized by subjecting monoethanolamine to
intermolecular dehydration reaction in the presence of a catalyst
to produce crude ethylenimine and then polymerizing this crude
ethylenimine in an aqueous medium.
[0027] A process for polymerizing crude ethylenimine in an aqueous
medium to produce the aqueous solution of the high molecular weight
ethylenimine polymer shall not specifically be restricted, and it
can be produced by a process usually used for producing an
ethylenimine polymer in an aqueous medium. The polymerization
catalyst and the polymerization conditions can suitably be selected
from those usually used for polymerizing ethylenimine. To be
specific, crude ethylenimine can be polymerized in an aqueous
medium in the presence of a polyhaloalkane, for example,
dichloroethane and dichloropropane (refer to Japanese Patent
Publication No. 8828/1968). Or, crude ethylenimine may be
polymerized with .alpha.,.beta.-unsaturated carboxylic acid or an
ester thereof in an aqueous medium (refer to Japanese Patent
Publication No. 24184/1967). Further, crude ethylenimine may be
addition-polymerized based on an ethylenimine polymer.
[0028] Lower amines such as ammonia, methylamine and ethylamine and
acetonitrile remain in a certain case in the aqueous solution of
the high molecular weight ethylenimine polymer obtained by
polymerizing in the manner described above. These impurities exert
adverse effects (generation of an offensive smell and a reduction
in the stability) to a quality of the ethylenimine polymer and
therefore are preferably removed as much as possible by a suitable
purifying process.
[0029] Further, according to the present invention, such purifying
process is provided as well. It is a process comprising heating and
condensing the aqueous solution of the high molecular weight
ethylenimine polymer obtained in the manner described above. To be
specific, taken is a means of heating and condensing the aqueous
solution of the high molecular weight ethylenimine polymer while
stirring at such a temperature that a temperature in the reactor
does not exceed 200.degree. C., preferably a temperature falling in
a range of 100 to 180.degree. C. after finishing the polymerization
reaction. The degree of concentration of the aqueous solution shall
not specifically be restricted, and the object can usually be
achieved by vaporizing and removing not much more than 10 to 50% by
weight of water contained in the aqueous solution of the
ethylenimine polymer (the above aqueous solution comprises usually
20 to 50% by weight of the ethylenimine polymer and 80 to 50% by
weight of water). The aqueous solution of the high molecular weight
ethylenimine polymer having a high purity in which all contents of
lower amines and acetonitrile are less than 1 ppm can be obtained
by this method. The heating and condensing operation may be carried
out either at atmospheric pressure or under reduced pressure, and
when it is carried out under reduced pressure, the pressure in the
reactor is preferably controlled to 10 to 700 mm Hg.
[0030] Various embodiments of the present invention have been
explained above, and according to the present invention, the
ethylenimine polymer having a weight average molecular weight of
1,000 to 1,000,000 (determined by gel permeation chromatography
(GPC); reduced to pulran) can simply and readily be obtained even
if any of the embodiments is employed. These ethylenimine polymers
have a quality which meets industrial standards and therefore are
widely used in the fields of, for example, a paper processing
agent, an adhesive, a pressure sensitive agent, paint, ink, a fiber
processing agent, a coagulating separator, cosmetics, toiletries
and a dispersant.
[0031] The present invention shall more specifically be explained
below with reference to examples. A series of Example I relates to
a production of the ethylenimine polymer; a series of Example II
relates to a purifying process of the ethylenimine polymer; a
series of Example III relates to a production of the aqueous
solution of the ethylenimine polymer; and a series of Example IV
relates to a purifying process of the aqueous solution of the
ethylenimine polymer. The units of ppm, % and parts in the
respective examples are based on weight unless otherwise
described.
EXAMPLE I-1
[0032] (Production of Crude Ethylenimine)
[0033] Dissolved in 2.4 liter of water was 900 g of aluminum
sulfate (9 hydrates), and a solution prepared by dissolving 357.6 g
of triammnium phosphate in 2.4 liter of water was added to this
solution while stirring. The resulting precipitate was filtered and
washed with water, and then it was kneaded well together with 73.6
g of barium oxide and 100 ml of water. The resulting clayish matter
was molded into a pellet form having a major diameter of about 5 mm
and a length of about 5 mm, and the pellets were dried and then
baked at 1000.degree. C. for 2 hours to obtain a catalyst having a
composition of Al.sub.1P.sub.1B.sub.0.2 in terms of an atomic ratio
excluding oxygen.
[0034] A stainless steel-made reactor having a minor diameter of 25
mm was charged with one liter of this catalyst and heated to
430.degree. C. by means of a heat transfer medium. Vaporized
monoethanolamine was passed through this reactor under conditions
of a pressure of 400 mm Hg at an outlet of the reactor and a space
velocity of 1000 h.sup.-1 to carry out continuous reaction.
Reaction mixed gas produced by the reaction had a composition of
67.6 volume % of monoethanolamine, 12.7 volume % of ethylenimine,
15.6 volume % of water, 1.34 volume % of acetaldehyde and others of
ammonia and dimers.
[0035] The reaction mixed gas was cooled down to 100.degree. C. and
then introduced into a stainless steel-made distilling tower having
a minor diameter of 50 mm and a height of 2000 mm. The tower was
charged with fillers (Macmafon packings) of 35 mm in a height of
1600 mm, and the reaction mixed liquid described above was
introduced into a part having a height of 1/3 from an upper part of
the charging tower. The liquid was distilled under a condition of a
reflux ratio of 4 to obtain crude ethylenimine from the tower
head.
[0036] This crude ethylenimine had the following contents of
ethylenimine and impurities contained therein.
[0037] Ethylenimine: 98.5%
[0038] Monoethanolamine: 400 ppm
[0039] Lower amines in total: 9000 ppm
[0040] Methylamine: 1000 ppm
[0041] Ethylamine: 6000 ppm
[0042] Ammonia: 2000 ppm
[0043] Acetonitrile: 400 ppm
[0044] Water: 400 ppm
EXAMPLE I-2
[0045] (Production of Ethylenimine Polymer)
[0046] A reactor equipped with a stirrer, a reflux condenser and a
thermometer was charged with 60 parts of ethylenediamine and 17
parts of 35% hydrochloric acid and heated. After elevating the
temperature, 1140 parts of the crude ethylenimine described above
was added thereto at 100 to 120.degree. C. in 10 hours under
refluxing. After finishing addition, the solution was ripened at
100 to 120.degree. C. for 2 hours to complete the reaction, whereby
an ethylenimine polymer (PEI-1) was obtained. After cooling down, a
viscosity, a pH, a resin content and a weight average molecular
weight of this PEI-1 were determined by the following methods. The
results thereof are shown in Table 1.
[0047] Viscosity (mPa.multidot.s/25.degree. C.): Determined by
means of a B type viscometer.
[0048] pH: A 5% aqueous solution was prepared to determine a pH by
means of a pH meter.
[0049] Resin content (%): The moisture was determined by a
[0050] Karl Fisher method, and the balance was set as the resin
content.
[0051] Weight average molecular weight: Pulran was used as a
standard substance to determine the molecular weight by means of
GPC.
EXAMPLE I-3
[0052] (Production of Ethylenimine Polymer)
[0053] A reactor equipped with a stirrer, a reflux condenser and a
thermometer was charged with 72 parts of PEI-1 obtained in Example
I-2 and 17 parts of 35% hydrochloric acid and heated. After
elevating the temperature, 1128 parts of the crude ethylenimine
obtained in Example I-1 was added thereto at 100 to 120.degree. C.
in 10 hours under refluxing. After finishing addition, the solution
was ripened at 100 to 120.degree. C. for 2 hours to complete the
reaction, whereby an ethylenimine polymer (PEI-2) was obtained.
After cooling down, a viscosity, a pH, a resin content and a weight
average molecular weight of this PEI-2 were determined in the same
manners as in Example I-2. The results thereof are shown in Table
1.
1TABLE 1 pH Resin Weight average Viscosity (5% aqueous content
molecular Example (mPa .multidot. s/25.degree. C.) solution) (mass
%) weight I-2 6150 11.1 99.7 3610 (PEI-1) I-3 86600 11.3 99.8 16560
(PEI-2)
Example II-1
[0054] (Production of Crude Ethylenimine)
[0055] Ethylenimine was produced according to a method described in
Example 1 of Japanese Patent Publication No. 55498/1993. That is,
monoethanolamine was continuously introduced into a reactor and
subjected to gas phase intermolecular dehydration reaction in the
presence of a phosphorus-alkaline earth metal base catalyst under
conditions of a temperature of 430.degree. C., a reduced pressure
of 400 mm Hg and a space velocity of 1000 h.sup.-1. The reaction
mixture was cooled down to 100.degree. C. at an outlet of the
reactor and condensed, and the condensate was introduced into a
continuous distilling tower to obtain crude ethylenimine distilled
from the tower head. Contained in this crude ethylenimine were 1000
ppm of methylamine, 6000 ppm of ethylamine, 400 ppm of acetonitrile
and 400 ppm of water.
EXAMPLE II-2
[0056] (Production of Ethylenimine Polymer)
[0057] A reactor equipped with a stirrer, a reflux condenser and a
thermometer was charged with 60 parts of ethylenediamine and 17
parts of 35% hydrochloric acid and heated. After elevating the
temperature, 1140 parts of the crude ethylenimine obtained in
Example 11-1 was added thereto at 100 to 120.degree. C. in 10 hours
under refluxing. After finishing addition, the solution was ripened
at 100 to 120.degree. C. for 2 hours to complete the reaction. The
ethylenimine polymer thus obtained had a weight average molecular
weight of 3610 (determined by gel permeation chromatography (GPC);
reduced to pulran) and a viscosity of 6150 (mPa -s/25.degree. C.; B
type viscometer). Contained in the ethylenimine polymer were 400
ppm of acetonitrile and 2000 ppm of lower amines such as
ammonia.
EXAMPLE II-3
[0058] (Purifying of Ethylenimine Polymer)
[0059] A flask of 2 liter put on an oil bath was charged with 1 kg
of the ethylenimine polymer obtained in Example 11-2, and nitrogen
gas was bubbled into the polymer at a rate of 0.2 N1/min at an
atmospheric pressure. A temperature of the polymer was maintained
at 120.degree. C. while bubbling. After bubbling for 5 hours, the
polymer was analyzed to find that both contents of acetonitrile and
lower amines were 1 ppm or less.
EXAMPLE II-4
[0060] (Purifying of Ethylenimine Polymer)
[0061] After adding 0.2 kg of water to 1 kg of the ethylenimine
polymer obtained in Example II-2, it was charged into a flask of 2
liter put on an oil bath and heated at an atmospheric pressure
under nitrogen atmosphere to vaporize and remove water. The
temperature of the oil bath was maintained at 105.degree. C. during
this operation. After heated and vaporized for 10 hours, the
polymer was analyzed to find that both contents of acetonitrile and
lower amines were 1 ppm or less and the water content was 14%.
EXAMPLE II-5
[0062] (Purifying of Ethylenimine Polymer)
[0063] After adding 0.2 kg of water to 1 kg of the ethylenimine
polymer obtained in Example II-2, it was charged into a flask of 2
liter put on an oil bath and heated while bubbling nitrogen gas
into the polymer at a rate of 0.2 Nl/min at an atmospheric pressure
to vaporize and remove water. The temperature of the oil bath was
maintained at 105.degree. C. during this operation. After heated
and bubbled for 8 hours, the polymer was analyzed to find that both
contents of acetonitrile lower amines were 1 ppm or less and the
water content was 14%.
EXAMPLE II-6
[0064] (Purifying of Ethylenimine Polymer)
[0065] After adding 0.2 kg of water to 1 kg of the ethylenimine
polymer obtained in Example II-2, it was charged into a flask of 2
liter put on an oil bath, and nitrogen gas was bubbled into the
polymer at a rate of 0.2 Nl/min at an atmospheric pressure. The
polymer mixture was slowly heated from 90.degree. C. up to
127.degree. C. in 3 hours to vaporize and remove water. After
heated and bubbled for 3 hours, the polymer was analyzed to find
that both contents of acetonitrile and lower amines were 1 ppm or
less and the water content was 10%.
EXAMPLE III-1
[0066] (Production of Crude Ethylenimine)
[0067] Dissolved in 2.4 liter of water was 900 g of aluminum
sulfate (9 hydrates), and a solution prepared by dissolving 357.6 g
of triammnium phosphate in 2.4 liter of water was added to this
solution while stirring. The resulting precipitate was filtered and
washed with water and then, it was kneaded well together with 73.6
g of barium oxide and 100 ml of water. The resulting clayish matter
was molded into a pellet form having a major diameter of about 5 mm
and a length of about 5 mm, and the pellets were dried and then
baked at 1000.degree. C. for 2 hours to obtain a catalyst having a
composition of Al.sub.1P.sub.1B.sub.0.2 in terms of an atomic ratio
excluding oxygen.
[0068] A stainless steel-made reactor having a minor diameter of 25
mm was charged with one liter of this catalyst and heated to
430.degree. C. by means of a heat transfer medium. Vaporized
monoethanolamine was passed through this reactor under conditions
of a pressure of 400 mm Hg at an outlet of the reactor and a space
velocity of 1000 h.sup.-1 to carry out continuous reaction.
Reaction mixed gas produced by the reaction had a composition of
67.6 volume % of monoethanolamine, 12.7 volume % of ethylenimine,
15.6 volume % of water, 1.34 volume % of acetaldehyde, and the
others were ammonia and dimers.
[0069] The reaction mixed gas described above was cooled down to
100.degree. C. and then introduced into a stainless steel-made
distilling tower having a minor diameter of 50 mm and a height of
2000 mm. The tower was charged with fillers (Macmafon packings) of
6.35 mm in a height of 1600 mm, and the reaction mixed liquid
described above was introduced into a part having a height of 1/3
from an upper part of the charging tower. The liquid was distilled
under a condition of a reflux ratio of 4 to obtain crude
ethylenimine from the tower head.
[0070] This crude ethylenimine had the following contents of
ethylenimine and impurities contained therein.
[0071] Ethylenimine: 98.5%
[0072] Monoethanolamine: 400 ppm
[0073] Lower amines in total: 9000 ppm
[0074] Methylamine: 1000 ppm
[0075] Ethylamine: 6000 ppm
[0076] Ammonia: 2000 ppm
[0077] Acetonitrile: 400 ppm
[0078] Water: 400 ppm
EXAMPLE III-2
[0079] (Production of Aqueous Solution of Ethylenimine Polymer)
[0080] A reactor equipped with a stirrer, a reflux condenser and a
thermometer was charged with 700 parts of water and 10 parts of
1,2-dichloroethane and heated. After elevating the temperature, 300
parts of the crude ethylenimine obtained in Example III-1 was added
thereto at 80.degree. C. in 4 hours. After finishing addition, the
solution was ripened at 80.degree. C. for 3 hours to complete the
reaction, whereby an aqueous solution of an ethylenimine polymer
was obtained. After cooling down, a viscosity, a pH, a resin
content and a weight average molecular weight of the aqueous
solution of the ethylenimine polymer were determined by the
following methods. The results thereof are shown in Table 2.
[0081] Viscosity (mPa.multidot.s/25.degree. C.): Determined by
means of a B type viscometer.
[0082] pH: A 5% aqueous solution was prepared to determine a pH by
means of a pH meter.
[0083] Resin content (%): The solution was dried at 150.degree. C.
for one hour by means of a hot air dryer, and the balance was set
as the resin content.
[0084] Weight average molecular weight: Pulran was used as a
standard substance to determine the molecular weight by means of
GPC.
2TABLE 2 pH Resin Weight average Viscosity (5% aqueous content
molecular Example (mPa .multidot. s/25.degree. C.) solution) (mass
%) weight III-2 275 10.8 30.2 121780
EXAMPLE IV-1
[0085] (Production of Aqueous Solution of Ethylenimine Polymer)
[0086] A flask reactor of 2 liter equipped with a stirrer, a reflux
condenser and a thermometer was charged with 700 parts of water and
10 parts of 1,2-dichloroethane and heated. After elevating the
temperature, 300 parts of the crude ethylenimine obtained in
Example II-1 described above was added thereto at 80.degree. C. in
4 hours. After finishing addition, the solution was ripened at
80.degree. C. for 3 hours to complete the reaction. The aqueous
solution of the ethylenimine polymer thus obtained was analyzed, to
result in finding that the polymer had a weight average molecular
weight of 121,780 (determined by gel permeation chromatography
(GPC); reduced to pulran) and a viscosity of 275
(mPa.multidot.s/25.degree. C.; B type viscometer) and that the
impurity contents were 160 ppm of acetonitrile and 800 ppm of lower
amines such as ammonia.
EXAMPLE IV-2
[0087] (Purifying of Aqueous Solution of Ethylenimine Polymer)
[0088] A flask reactor equipped with a stirrer, an steam-condensing
and drawing device and a thermometer which was put on an oil bath
was charged with 1000 g of the aqueous solution of the ethylenimine
polymer obtained in Example IV-1 and heated at 110.degree. C. at an
atmospheric pressure. Distilled water was cut, and when the resin
content became 35%, the solution was analyzed. As a result thereof,
it was found that acetonitrile had a content of 0.9 ppm and lower
amines had a content of 2.0 ppm. Vaporization was further
accelerated to condense the solution, and when the resin content
reached 40%, the solution was analyzed to result in finding that
both of the contents of acetonitrile and lower amines were 1 ppm or
less.
* * * * *