JP2745381B2 - Method for producing sulfonic acid group-containing polyamide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a water-soluble polyamide, and more particularly to a novel method for producing a sulfonic acid group-containing polyamide.

[0002]

2. Description of the Related Art Attempts to introduce sulfonic acid groups into water-insoluble polymers to make them water-soluble and to utilize them have recently attracted attention due to pollution problems. In particular, polyamide has excellent heat resistance, toughness, and film-forming properties, but has a problem that it is soluble only in highly toxic amide solvents, and its application field is significantly restricted. On the other hand, as a method for synthesizing a polyamide, a method for synthesizing a polyamide by reacting a dicarboxylic acid and a diamine in the presence of a phosphite and pyridine or a derivative thereof is known. However, it is not known to use a monomer containing a sulfonic acid group as a diamine component or a dicarboxylic acid component in this method.

[0003]

Conventionally, as an attempt to introduce a sulfonic acid group into a polyamide as described above to make it soluble in water, an acid chloride method of polycondensing a diamine component and an acid chloride component has been carried out. (EJ VANDENBERG, WR D
IVELEY, LJ FILAR, SR PATEL, and HG BARTH J.
Polym. Sci. Polym. Chem. Vol. 127, 3745-3757 (198
9)) In this method, a product having a high degree of polymerization can be easily obtained, but it is difficult to purify the monomers used, it is difficult to control the reaction at the time of production, and hydrochloric acid gas as a reaction by-product is used. And various other problems. The present invention
The present invention has been made in view of the above problems in the conventional technology. That is, an object of the present invention is to provide a novel production method for synthesizing a sulfonic acid group-containing polyamide under a simple and mild condition.

[0004]

Means for Solving the Problems The present inventors have conducted research to solve the above-mentioned problems in the prior art, and as a result, have found that a sulfonic acid group can be obtained in the presence of a phosphite and pyridine or a derivative thereof. It has been found that when a compound containing is used as a diamine component or a dicarboxylic acid component, polycondensation proceeds under mild conditions without protecting the sulfonic acid group, and the present invention has been completed. That is, the present invention uses, when producing a sulfonic acid group-containing polyamide by polycondensing a diamine component and a dicarboxylic acid component, a compound having a sulfonic acid group in at least one of the diamine component and the dicarboxylic acid component. The polycondensation is carried out in the presence of a phosphite and pyridine or a derivative thereof.

Hereinafter, the present invention will be described in detail. In the present invention, a compound having a sulfonic acid group in at least one of the diamine component and the dicarboxylic acid component of the raw material is used. As the compound containing a sulfonic acid group used as the diamine component, any compound containing a sulfonic acid group such as an aliphatic, alicyclic or aromatic diamine compound having one or more sulfonic acid groups can be used. Can be used,
Aromatic diamine compounds are preferred. Preferred specific examples thereof include, for example, 3,5-diaminobenzenesulfonic acid, 3,4-diaminobenzenesulfonic acid, 2,4-diaminobenzenesulfonic acid, and 4,4′-diaminostilbene-2,2′-disulfonic acid. And 4,4'-diaminobiphenyl-2,2'-disulfonic acid.

[0006] The compound containing a sulfonic acid group used as a dicarboxylic acid component of the raw material includes 1
Aliphatic, aliphatic and aromatic diamine compounds having one or more sulfonic acid groups, such as those having a sulfonic acid group, can be used, but aromatic dicarboxylic acids are preferred. . Preferred specific examples thereof include 3,5-dicarboxybenzenesulfonic acid and 3,4-dicarboxybenzenesulfonic acid.

In the present invention, a diamine or a dicarboxylic acid containing no sulfonic acid group may be used in combination with the diamine component and the dicarboxylic acid component. In the present invention, the sulfonic acid group-free diamine and dicarboxylic acid that can be used as a raw material include:
There is no particular limitation, and any known material as a raw material for polyamide can be used. Specifically, as diamines, for example,
4,4'-ethylenediamine, 4,4-isopropylidenediamine, metaphenylenediamine, paraphenylenediamine, 3,4'-oxydianiline, 4,4'-oxydianiline, 3,3'-sulfonyldianiline, 4,
4'-sulfonyldianiline, 1,4-naphthalenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, 1,3-bis (m-aminophenyl)-
1,1,3,3-tetramethyldisiloxane, 4,4 '
-Bis (4-aminophenoxy) diphenyl sulfone,
4,4'-bis (3-aminophenoxy) diphenylphone, 4,4'-bis (4-aminophenoxy) benzophenone, 4,4'-bis (3-aminophenoxy) benzophenone, 4,4'-bis ( 4-aminophenylmercapto) benzophenone, 4,4'-bis (4-aminophenylmercapto) benzophenone, 2,2'-bis [4- (2-trifluoromethyl-4-aminophenoxy) phenyl] hexafluoropropane, 2,2'-
Bis [4- (3-trifluoromethyl-5-aminophenoxy) phenyl] hexafluoropropane, 2,2 '
-Bis [4- (3-trifluoromethyl-4-aminophenoxy) phenyl] hexafluoropropane, 2,
2'-bis [4 (2-trifluoromethyl-5-aminophenoxy) phenyl] hexafluoropropane, 2,
2'-bis [4- (4-trifluoromethyl-5-aminophenoxy) phenyl] hexafluoropropane,
2,2'-bis [4- (2-nonafluorobutyl-5-
Aminophenoxy) phenyl] hexafluoropropane, 2,2'-bis [4- (4-nonafluorobutyl-
5-aminophenoxy) phenyl] hexafluoropropane, 4,4'-diaminodiphenylmethane, o-tolidine, o-dianisidine, 2,5-diaminopyridine,
3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2-bis (4-hydroxy-3-aminophenyl) hexafluoropropane and the like can be mentioned. A plurality of them may be used in combination.

As the dicarboxylic acids containing no sulfonic acid group, aliphatic, alicyclic and aromatic dicarboxylic acids can be used. For example, isophthalic acid, terephthalic acid, 4,4'-biphenyldicarboxylic acid, 3,3'-methylene dibenzoic acid, 4,4'-methylene dibenzoic acid,
4,4'-oxydibenzoic acid, 4,4'-thiodibenzoic acid, 3,3'-carbonyldibenzoic acid, 4,4'-carbonyldibenzoic acid, 4,4'-sulfonyldibenzoic acid,
1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, succinic acid, glutaric acid, suberic acid, azelaic acid, sebacic acid, undecandioic acid, 1,3-cyclohexadicarboxylic acid Acid, 1,4-cyclohexadicarboxylic acid, malonic acid,
Methylmalonic acid, dimethylmalonic acid, adipic acid, 1,
10-decandioic acid, phenylmalonic acid, benzylmalonic acid, phenylsuccinic acid, 3-phenylglutaric acid, homophthalic acid, 1,3-phenylene diacetic acid, 1,4-phenylene diacetic acid, 4-carboxyphenyl acetic acid, 5-bromo-N- (carboxymethyl) anthranilic acid, m-carboxycinnamonic acid, 5-hydroxyisophthalic acid,
Dicarboxylic acids such as -hydroxy-2,5-dicarboxypyridine and derivatives thereof. These may be used alone or in combination of two or more.

In the present invention, the diamine component and the dicarboxylic acid component are combined with an amide organic solvent represented by N-methyl-2-pyrrolidone in the presence of a phosphite and pyridine or a derivative thereof. To carry out polycondensation by heating under an inert atmosphere such as nitrogen. In this case, phosphites used include diphenyl phosphite, triphenyl phosphite, tri-o-tolyl phosphite, di-o-tolyl phosphite, and tri-m-phosphite. Tolyl, di-m-tolyl phosphite, tri-p-tolyl phosphite, di-p-tolyl phosphite, di-o-chlorophenyl phosphite, tri-p-chlorophenyl phosphite, phosphorous acid Di-p-chlorophenyl and the like can be mentioned,
It is not limited to these. Pyridine or a derivative thereof used together with a phosphite is pyridine, 2-picoline, 3-picoline, 4-picoline, 2,4-lutidine, 2,6-lutidine, 3,5-
Lutidine and the like can be mentioned. The amount of the phosphite used in the polycondensation is preferably an equimolar amount or more with respect to the carboxyl group, but the use of a 30-fold molar amount or more is not economically advantageous. Further, the amount of pyridine or a derivative thereof to be used must be at least equimolar to the carboxyl group.

The polycondensation reaction is usually preferably carried out by a solution polymerization method using the above pyridine or a derivative thereof mixed with an amide organic solvent in the form of a mixed solvent. The amide-based organic solvent used must be a solvent that does not substantially react with both the reaction components and the phosphite, but is a good solvent for both the reaction components, and also for the polyamide of the reaction product. A good solvent is preferred. However, a solvent that becomes heterogeneous as the polycondensation proceeds may be used. Specific examples of the amide-based organic solvent preferably used in the present invention include N 2
-Methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide and the like. The mixed solvent may be used in such an amount that both reaction components are contained at a concentration of 5 to 30% by weight. In the present invention, in order to obtain a polyamide having a high degree of polymerization, an alkali metal salt or an alkaline earth metal salt represented by lithium chloride and calcium chloride can be added to the reaction mixture.

The polycondensation reaction is preferably performed in an inert atmosphere such as nitrogen. The reaction temperature is preferably in the range of 60 to 140 ° C, more preferably at a temperature lower than the boiling point of pyridine or a derivative thereof. The reaction time is greatly affected by the reaction conditions, but is often performed in the range of several minutes to 48 hours.

In the present invention, when the diamine component and the dicarboxylic acid component are used in equimolar amounts under the above reaction conditions, a sulfonic acid group-containing polyamide having a high degree of polymerization can be obtained. Also, one of them can be used in excess to obtain one having a small average degree of polymerization. After the completion of the reaction, the reaction mixture is poured into methanol to separate the produced polymer, and further purified by a reprecipitation method to remove by-products, inorganic salts, and the like, thereby obtaining the target sulfonic acid group-containing polyamide. Obtainable.

The content of the sulfonic acid group in the sulfonic acid group-containing polyamide synthesized by the production method of the present invention is determined in such a manner that all of the repeating structural units have a sulfonic acid group in order to have water-soluble properties. May be used, but the proportion of the repeating structural unit containing a sulfonic acid group in all the repeating structural units is preferably at least 20 mol%.

[0014]

In the polycondensation reaction for synthesizing polyamide,
Polyamide can be produced by simply mixing and heating a diamine component having an amino group and a carboxyl group at both ends and a dicarboxylic acid component, in which case the polycondensation reaction needs to be performed at a high temperature, and as a result, Involvement of side reactions such as amide exchange reaction is inevitable. In particular, when a compound containing a sulfonic acid group is used as a raw material component, if a polycondensation reaction is performed without protecting the sulfonic acid group, a side reaction with the sulfonic acid group cannot be avoided. However, in the present invention, since the polycondensation reaction is performed using phosphites and pyridine or a derivative thereof as a condensing agent,
The polycondensation reaction proceeds at a relatively low temperature, thereby avoiding side reactions such as the transamidation reaction and the like. A sulfonic acid group-containing polyamide having a regulated structure can be easily produced at a high yield without causing a reaction. Sulfonic acid group-containing polyamide produced according to the present invention, starch, polyvinyl alcohol, polyethylene oxide, polyacrylamide,
It can be used as a mixture with a water-soluble resin typified by polyvinylpyrrolidone or the like, or for modification of a water-soluble resin, and is useful as a water-based paint, a water-based adhesive, and the like.

[0015]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Example 1 Synthesis of a sulfonic acid group-containing polyamide using 2,4-diaminobenzenesulfonic acid as a diamine component In a 100 ml three-necked round bottom flask, isophthalic acid 1.6 was added.
61 g (10 mmol), 1.882 g (10 mmol) of 2,4-diaminobenzenesulfonic acid, 0.12 g of lithium chloride, 0.36 g of potassium chloride, N-methyl-
20 ml of 2-pyrrolidone, 3 ml of pyridine and 6.2 g of triphenyl phosphite were added, and the mixture was heated at 100 ° C. under a dry nitrogen atmosphere.
For 4 hours. After completion of the reaction, the polymer solution was poured into 1 liter of methanol to precipitate the polymer. After filtration, unreacted monomers and inorganic metal salts were removed in hot methanol. After filtration, vacuum drying, yield 9
The sulfonic acid group-containing polyamide of the present invention was obtained at 7%. The intrinsic viscosity of this polyamide was 0.75 dl / g at 30 ° C. at a polymer solution concentration of 0.5 g / dl in N, N-dimethylacetamide. The structure was confirmed by measuring the IR spectrum (KBr tablet method).
The absorption based on the amide carbonyl group near 50 cm ^-1
An absorption based on a sulfonic acid group was observed at around 1200 cm ^-1 . This polyamide was soluble in water.

Example 2 Synthesis of a sulfonic acid group-containing polyamide using 2,4-diaminobenzenesulfonic acid and 3,4'-oxydianiline as diamine components In a 100 ml three-necked round bottom flask, isophthalic acid 1.6 was added.
61 g (10 mmol), 0.941 g (5 mmol) of 2,4-diaminobenzenesulfonic acid, 5 mmol of 3,4'-oxydianiline 1.001 g, lithium chloride 0.12 g, potassium chloride 0.36 g, N- Methyl-
20 ml of 2-pyrrolidone, 3 ml of pyridine and 6.2 g of triphenyl phosphite were added, and the mixture was heated at 100 ° C. under a dry nitrogen atmosphere.
For 4 hours. After completion of the reaction, the polymer solution was poured into 1 liter of methanol to precipitate the polymer. After filtration, unreacted monomers and inorganic metal salts were removed in hot methanol. After filtration, vacuum drying, yield 9
At 8%, a sulfonic acid group-containing polyamide of the present invention was obtained. The intrinsic viscosity of this polyamide was 0.64 dl / g at 30 ° C. at a polymer solution concentration of 0.5 g / dl in N, N-dimethylacetamide. The structure was confirmed by measuring the IR spectrum (KBr tablet method).
The absorption based on the amide carbonyl group near 50 cm ^-1
An absorption based on a sulfonic acid group was observed at around 1250 cm ^-1 . This polyamide was soluble in water.

Example 3 Synthesis of a sulfonic acid group-containing polyamide using 3,5-dicarboxybenzenesulfonic acid as a dicarboxylic acid component In a 100 ml three-necked round bottom flask, 2.462 g (10 Mmol),
2.02 g (10 mmol) of 3,4'-oxydianiline, 0.12 g of lithium chloride, 0.3% of potassium chloride
6 g, 20 ml of N-methyl-2-pyrrolidone, 3 ml of pyridine and 6.2 g of triphenyl phosphite were added and reacted at 100 ° C. for 4 hours in a dry nitrogen atmosphere. After the reaction,
Pour the polymer solution into one liter of methanol,
The polymer was precipitated. After filtration, unreacted monomers and inorganic metal salts were removed in hot methanol. After filtration,
After vacuum drying, a sulfonic acid group-containing polyamide of the present invention was obtained at a yield of 98%. The intrinsic viscosity of this polyamide is N, N-
In dimethylacetamide, polymer solution concentration 0.5g /
dl, at 30 ° C., 0.60 dl / g. As a result of observation of the structure and IR spectrum (KBr tablet method), absorption based on the amide carbonyl group near 1650 cm ^-1 is absorption based on sulfonic acid groups was observed around 1250 cm ^-1. This polyamide was soluble in water.

[0018]

According to the present invention having the above-mentioned constitution, it is difficult to purify monomers used for synthesis and to control the reaction at the time of production, as in the production of conventional sulfonic acid group-containing polyamides. It is not necessary to consider production problems such as the generation of hydrochloric acid gas as a reaction product, and it is possible to easily produce a sulfonic acid group-containing polyamide with a regulated structure at a relatively low temperature without side reactions at a high yield. can do. Therefore, the present invention contributes to expanding the field of application as a water-soluble polyamide.

Claims (3)

(57) [Claims] When producing a sulfonic acid group-containing polyamide by polycondensing a diamine component and a dicarboxylic acid component, a compound having a sulfonic acid group is used for at least one of the diamine component and the dicarboxylic acid component. A method for producing a sulfonic acid group-containing polyamide, wherein the polycondensation is carried out in the presence of a phosphite and pyridine or a derivative thereof. 2. The method according to claim 2, wherein the compound having a sulfonic acid group is 3,5-
The method for producing a sulfonic acid group-containing polyamide according to claim 1, which is a diamino aromatic sulfonic acid selected from diaminobenzenesulfonic acid, 3,4-diaminobenzenesulfonic acid, and 2,4-diaminobenzenesulfonic acid. 3. The method according to claim 1, wherein the compound having a sulfonic acid group is 3,5-
The method for producing a sulfonic acid group-containing polyamide according to claim 1, which is a dicarboxy aromatic sulfonic acid selected from dicarboxybenzenesulfonic acid and 3,4-dicarboxybenzenesulfonic acid.