JP2000041692A - Production of polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a soluble branched-chained polyester under simple and mild conditions. SOLUTION: A dicarboxylic acid or a dicarboxylic acid derivative having <=1,000 molecular weight is reacted with a trifunctional or polyfunctional aliphatic alcohol having <=1,000 molecular weight in the presence of a hydrolase such as lipase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a soluble reactive branched polyester. More specifically, the present invention relates to a method for producing a soluble reactive branched polyester under simple and mild conditions.

[0002]

2. Description of the Related Art Branched polymers are expected to be used in various applications because their physical properties are different from those of linear polymers. Usually, the production of an aliphatic linear polyester is carried out at a high temperature of 150 ° C. or more using a dicarboxylic acid alkyl ester and a diol using a chemical catalyst. At this time, if the reaction is carried out in a combination containing a trifunctional or higher polyfunctional monomer in the raw material, a three-dimensional condensation reaction occurs, and a gel insoluble in a solvent is obtained. Therefore, a method for producing a branched polyester that does not cause gelation has been desired.

On the other hand, it has been shown that polyester can be synthesized by using an enzyme catalyst. For example,
Chem. Soc. Perkin. Trans. ,
In 1,899 (1993), a polyester is synthesized from adipic acid and 1,4-butanediol using lipase. However, since the synthesis was a reaction between divalent monomers, the resulting polyester was a linear polymer and not a branched polymer. In addition, there has been no report of producing a soluble branched polyester by reacting a dicarboxylic acid or a dicarboxylic acid derivative with a trihydric or higher aliphatic alcohol in the presence of a hydrolase.

[0004]

SUMMARY OF THE INVENTION The present invention provides a simple and mild branched polyester which does not produce a gel insoluble in a solvent even when the reaction is carried out in combination with a raw material containing a trifunctional or higher polyfunctional monomer. Provided is a method for manufacturing under conditions.

[0005]

That is, the present invention provides a compound having a molecular weight of 1
The present invention relates to a method for producing a polyester, comprising reacting a dicarboxylic acid or a dicarboxylic acid derivative having a molecular weight of 1,000 or less with an aliphatic alcohol having a molecular weight of 1,000 or more and having a valence of 3 or more in the presence of a hydrolase.

[0006] The present invention further relates to a method for producing the above polyester, wherein the hydrolase is lipase.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

The molecular weight used in the present invention is 1000
The following dicarboxylic acids are not particularly limited as long as they react with an aliphatic alcohol in the presence of a hydrolase. For example, citraconic acid, malic acid, citric acid, oxalic acid,
Malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, fumaric acid, itaconic acid, maleic acid diglycolic acid, dimer acid Aliphatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylene diacetic acid, m-phenylenediglycolic acid, and p-phenylenediic acid Glycolic acid,
o-phenylenediglycolic acid, diphenylacetic acid, diphenyl-p, p'-dicarboxylic acid, naphthalene-1,4
-Dicarboxylic acid, naphthalene-1,5-dicarboxylic acid,
Aromatic dicarboxylic acids such as naphthalene-2,6-dicarboxylic acid, anthracenedicarboxylic acid, trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, and cyclohexane-3,5-diene-
Examples thereof include alicyclic dicarboxylic acids such as 1,2-carboxylic acid and hexahydroterephthalic acid.

The molecular weight used in the present invention is 1000
Examples of the following dicarboxylic acid derivatives include dicarboxylic acid diesters, dicarboxylic acid monoesters, and dicarboxylic anhydrides. These dicarboxylic acid derivatives are
There is no particular limitation as long as it reacts with the aliphatic alcohol in the presence of the hydrolase. Further, the dicarboxylic acid may be a polycarboxylic acid such as a tricarboxylic acid and a tetracarboxylic acid.

Specific examples of dicarboxylic acid diesters include diethyl oxalate, diphenyl oxalate, divinyl oxalate, diethyl succinate, diphenyl succinate, divinyl succinate, diethyl malonate, diphenyl malonate, divinyl malonate, and adipic acid. Diethyl, diphenyl adipate, diisopropenyl adipate, divinyl adipate, dimethyl sebacate, methyl vinyl sebacate, diethyl sebacate, diphenyl sebacate, divinyl sebacate, diisopropenyl sebacate, dimethyl citrate, trimethyl citrate Diesters of aliphatic dicarboxylic acids such as dimethyl phthalate, diphenyl phthalate, divinyl phthalate, dimethyl isophthalate, diphenyl isophthalate, divinyl isophthalate, dimethyl terephthalate, terephthalate Diphenyl, and aromatic dicarboxylic acid diester such as terephthalic acid divinyl.

Specific examples of dicarboxylic acid monoesters include dicarboxylic acid monoesters corresponding to the above dicarboxylic acid diesters.

Specific examples of dicarboxylic anhydrides include aliphatic dicarboxylic anhydrides such as phthalic anhydride, succinic anhydride, and maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, hymic anhydride, and hetic anhydride. , Alicyclic dicarboxylic anhydrides such as methylcyclohexentricarboxylic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, trimellitic anhydride,
Examples thereof include polycarboxylic anhydrides such as pyromellitic anhydride. Two or more of these dicarboxylic acids or dicarboxylic acid derivatives may be used.

The molecular weight used in the present invention is 1000.
The trihydric or higher aliphatic alcohol is not particularly limited as long as it reacts with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a hydrolase. For example, glycerin, trimethylolethane, trimethylolpropane,
Trihydric aliphatic alcohols such as trishydroxymethylaminomethane and 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, hexamethylolmelamine, tetramethylolbenzoguanamine, tetraethylolbenzoguanamine, and dipentaerythritol Examples include aliphatic alcohols having a valency of at least 3, glucose, mannose, galactose, fructose, xylose, glucosamine, maltose, sugars such as cellobiose and sucrose, and oligomers having a hydroxyl group in the side chain such as polyvinyl alcohol having a molecular weight of 1,000 or less.

The trihydric or higher alcohol may be used in combination of two or more.

A dihydric alcohol may be used in combination for adjusting the viscosity and the glass transition temperature. However,
The use of dihydric alcohols lowers the molecular weight and broadens the molecular weight distribution.

The present invention utilizes an ester synthesis reaction catalyzed by a hydrolase. Therefore, the hydrolase used in the present invention is not particularly limited as long as it catalyzes an ester synthesis reaction, and examples thereof include carboxyesterase, lipase, phospholipase, acetylesterase, pectin esterase, cholesterol esterase, tannase, and monoacyl. Esterase, glucosidase, galactosidase, glucuronidase, xylosidase, etc. classified into 3.1 groups of EC (enzyme number) such as glycerol lipase, lactonase, lipoprotein lipase, etc. Hydrolases classified into EC 3.2 group acting on glycosyl compounds of the following, hydrolases classified into EC 3.3 group such as epoxide hydrolase,
E acting on peptide bonds such as aminopeptidase, chymotrypsin, trypsin, plasmin and subtilisin
Examples thereof include hydrolases classified into the group C3.4 and hydrolases classified into the group EC3.7 such as phloretin hydrolase.

Among the above esterases, the enzyme that hydrolyzes glycerol esters to release fatty acids is particularly called a lipase. Lipases have the advantages of catalyzing the ester synthesis reaction with high yield and being available at a low cost. Therefore, it is preferable to use a lipase in the method for producing a polyester of the present invention.

Although lipases of various origins can be used, Pseudomonas is preferred.
nas), Alcaligenes, Achromobacter, Candid
a) Lipases obtained from microorganisms such as genera, Aspergillus, Rhizopus, Mucor, etc., lipases obtained from plant seeds, lipases obtained from animal tissues, pancreatin, stearpsin, etc. Can be mentioned. this house,
It is desirable to use a lipase derived from a microorganism of the genus Pseudomonas, Candida, Aspergillus, or Rhizopus. Specific examples include Pseudomonas fluorescens, Peudomonas cepasia, Candida antarctica, Candida rugosa, Aspergillus niger, and Razops higer.
pus delemer), Rhizopus japonicus (Rhizopus)
japonicus). In the present invention, two or more types of hydrolases may be used as a mixture, and an enzyme immobilized by a known method may be used in order to stabilize the enzyme and facilitate recovery after the reaction. Is also possible.

In the present invention, a solvent can be used if necessary. As the solvent, those which do not hinder the activity of the hydrolase are preferable, for example, hexane, cyclohexane, heptane, octane, isooctane which is an aliphatic hydrocarbon solvent, benzene, toluene, dichlorobenzene, and chlorobenzene which are aromatic hydrocarbon solvents , Anisole, halogenated hydrocarbon solvents chloroform, dichloromethane, dichloroethane, carbon tetrachloride, ether solvents diethyl ether, dioxane, tetrahydrofuran, diisopropyl ether, di-n-
Butyl ether, polar solvent isopropanol, t
-Amyl alcohol, acetonitrile, ethyl acetate and the like.

In the production of the present invention, a low-molecular compound is produced as a by-product of the condensation reaction. However, in order to promote the reaction, there is no problem even if a method of rapidly removing this by-product from the reaction system is used. There is no. In order to remove by-products from the reaction system, the conditions in which the by-products are present in a vapor state are used, and the vapor-like by-products are discharged from the reaction system together with the inert gas, or are discharged outside the reaction system by a distillation column. be able to. In order to remove by-products from the reaction system, the reaction can be performed under reduced pressure to remove by-products.

In the production method of the present invention, there is no problem if the dicarboxylic acid or the dicarboxylic acid derivative and the aliphatic alcohol maintain a solid or liquid state and also maintain a dispersed state with the solid hydrolase. Absent.

In the present invention, the molar ratio of the dicarboxylic acid or the dicarboxylic acid derivative to the aliphatic alcohol is preferably in the range of 10: 1 to 1:10, more preferably 3: 1. 1-1: 3 is desirable. The reaction temperature is preferably -10 to 120 ° C, which is a range in which the enzyme is not inactivated, and particularly preferably 20 to 80 ° C.

In the present invention, the amount of the hydrolase to be added may be appropriately adjusted depending on the ester synthesizing ability of the hydrolase used, but is preferably 0 to the total amount of the dicarboxylic acid or the dicarboxylic acid derivative and the aliphatic alcohol. 0.01 to 1000% by weight, more preferably 0.1 to 1000% by weight.
It may be 100% by weight. At this time, even if the enzyme is used in a large amount, no side reaction occurs, and the purification operation of the obtained polyester is not hindered.

In this production method, all hydroxyl groups of the alcohol used are not deposited in the esterification reaction.
Therefore, it is considered that a polyester can be obtained without gelling even when a trivalent or higher alcohol is used. The amount of the remaining hydroxyl group varies depending on the production method such as the type of alcohol used, but it is 1 mol equivalent to 500 mol per mol of the polymer.
The molar equivalent is within the range, and the reactivity of the hydroxyl group remaining in the polymer can be used to modify or cure the polymer by, for example, reacting with isocyanate or epoxy.

The branched polyester of the present invention can be prepared by using various solvents such as chloroform, tetrahydrofuran (THF), dimethylformamide (DMF), dimethylsulfoxide (DMSO), chlorobenzene, acetone, methyl ethyl ketone, cyclohexanone, ethyl acetate, toluene, It is soluble in xylene and has excellent handling.

The weight average molecular weight of the polyester obtained in the present invention is 300 to 300,000 in terms of polystyrene as determined by GPC, usually 500 to 10
It is in the range of 0000.

[0027]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. (Example 1) 0.1 g of lipase (from Candida antarctica) was added to 0.51 g of divinyl sebacate and 0.18 g of glycerin. This was heated at 60 ° C. for 8 hours under an argon atmosphere. Then 5 mL of chloroform
In addition, the enzyme was removed by filtration, and the filtrate was concentrated under reduced pressure. This was poured into a large amount of a 50% aqueous methanol solution to precipitate a polymer. The polymer was recovered by filtration and dried under vacuum. Yield 0.39 grams. The weight average molecular weight determined in terms of polystyrene was 20,000 from GPC. The obtained polyester was soluble in chloroform, THF, DMSO, and DMF. 1H NMR, 13C NMR and two-dimensional NMR confirmed that OH of glycerin remained and that the polyester was a branched polyester. (Example 2) The same operation as in Example 1 was performed except that the charged amount of divinyl sebacate was 0.76 g. Yield 0.
59 grams. The weight average molecular weight calculated in terms of polystyrene is
It was 2,300 from GPC. 1H NMR, 13C NMR and two-dimensional NMR confirmed that OH of glycerin remained and that the polyester was a branched polyester. (Example 3) The same operation as in Example 1 was performed, except that a lipase derived from Mucor miehei was used. yield
0.26 g. The weight average molecular weight determined in terms of polystyrene was 3,000 from GPC. 1H NMR, 13C NMR, 2D NMR
It was further confirmed that OH of glycerin remained and that the polyester was a branched polyester. (Example 4) The same operation as in Example 1 was performed except that a lipase derived from Pseudomonas cepacia was used. Yield 0.19 grams. The weight average molecular weight determined in terms of polystyrene was 4,700 from GPC. 1H NMR, 13C NMR,
From the two-dimensional NMR, it was confirmed that OH of glycerin remained and that it was a branched polyester. Example 5 The same operation as in Example 1 was performed except that 0.27 g of 1,2,6-hexanetriol was used instead of glycerin. Yield 0.43 grams. The weight average molecular weight determined in terms of polystyrene was 14,000 from GPC. 1H NMR, 1
OH of 1,2,6-hexanetriol from 3C NMR and 2D NMR
Was remained and it was confirmed that it was a branched polyester. (Example 6) Sebacic acid instead of divinyl sebacate
The same operation as in Example 1 was performed except that the reaction was performed under reduced pressure using 0.40 g. Yield 0.35 grams. The weight average molecular weight determined in terms of polystyrene was 9,500 from GPC. 1H NMR, 13C NMR and two-dimensional NMR confirmed that OH of glycerin remained and that the polyester was a branched polyester.

[0028]

According to the present invention, a soluble reactive branched polyester can be produced easily and under mild conditions.

Claims (2)

[Claims] 1. A method for producing a polyester, comprising reacting a dicarboxylic acid or dicarboxylic acid derivative having a molecular weight of 1,000 or less with a trihydric or higher valent aliphatic alcohol having a molecular weight of 1,000 or less in the presence of a hydrolase. 2. The method for producing a polyester according to claim 1, wherein the hydrolase is lipase.