JP2001316465A - Polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a straight chained polyester which is obtained in a mild condition and excellent in solubility in an aqueous solvent. SOLUTION: A polyester is obtained by reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyester obtained by reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase. More specifically, the present invention relates to a polyester useful as a curable polymer, a thermosetting resin material, a reactive polymer, a film-forming material, an ink coating material, a biocompatible polymer, and a biodegradable polymer.

[0002]

2. Description of the Related Art It has been shown that a polyester can be synthesized by using an enzyme catalyst. For example, Ch
em. Soc. Perkin. Trans. , 1,8
On page 99 (1993), a polyester is synthesized from adipic acid and 1,4-butanediol using lipase. However, the synthesis is not a synthesis using sugar alcohols. Ann. NY Acad. Sci., 672
In Volume 352 (1992), a polyester is obtained by reacting sucrose with divinyl adipate in the presence of an alkaline protease, but the synthesis does not use a sugar alcohol. The catalyst is also a protease,
In consideration of the development of applied applications and the cost of the catalyst, a synthesis method using an inexpensive lipase, which has been extensively studied in detail and industrially produced, is desirable.

Further, attempts have been made to obtain a polyester by reacting a polyhydric alcohol and a carboxylic acid in the presence of a hydrolase (for example, see JP-A-10-19).
In this case, a branched or gel-like polyester is provided instead of a linear polyester,
There has been a demand for further improvement in handling as a polyester useful as a coating film forming material, a reactive polymer, an ink raw material, and a biodegradable polymer.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a polyester obtained by reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase. More specifically, an object of the present invention is to provide a linear polyester obtained under mild conditions and having excellent solubility in an aqueous solvent.

[0005]

That is, the present invention relates to a polyester obtained by reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase.

Further, the present invention relates to the above polyester, wherein the sugar alcohol is sorbitol, xylitol, mesoerythritol, mannitol, N-methylglucamine.

Further, the present invention provides that the number average molecular weight is 800 to 3
It is related to the above polyester, which is 0.000

Further, the present invention relates to a method for producing a polyester, which comprises reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase.

Further, the present invention relates to a method for producing the above polyester, wherein the sugar alcohol is sorbitol, xylitol, mesoerythritol, mannitol, or N-methylglucamine.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The sugar alcohol used in the present invention is a chain polyhydric alcohol obtained by reducing a carbonyl group of a sugar molecule to convert it to a hydroxyl group,
There is no particular limitation as long as it reacts with the lipase to give a polyester. For example, D-arabinitol, L
-Arabinitol, erythritol, galactitol,
myo-inositol, mannitol, perseitol,
Ribitol, sorbitol, xylitol, mesoerythritol, N-methylglucamine and the like can be mentioned. Preferably, sorbitol, xylitol, mesoerythritol, mannitol, N-methylglucamine can be used.

The dicarboxylic acid used in the present invention is not particularly limited as long as it reacts with lipase to give a polyester. For example, citraconic acid, malic acid, citric acid, oxalic acid, malonic acid, succinic acid, Aliphatic dicarboxylic acids such as 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, and dimer acid , Phthalic acid, isophthalic acid,
Terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p
-Phenylene diacetate, m-phenylenediglycolic acid,
p-phenylenediglycolic acid, o-phenylenediglycolic acid, diphenylacetic acid, diphenyl-p, p'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6 −
Aromatic dicarboxylic acids such as dicarboxylic acid, anthracene dicarboxylic acid, trimellitic acid, pyromellitic acid, naphthalene tricarboxylic acid, and naphthalene tetracarboxylic acid; cyclohexane-3,5-diene-1,2-carboxylic acid;
Alicyclic dicarboxylic acids such as hexahydroterephthalic acid can be mentioned.

The dicarboxylic acid derivative used in the present invention is not particularly limited as long as it reacts with lipase to give a polyester. Examples thereof include diethyl oxalate, diphenyl oxalate, divinyl oxalate, diethyl succinate, and succinate. Diphenyl acid, divinyl succinate, diethyl malonate, diphenyl malonate, divinyl malonate, diethyl adipate, diphenyl adipate, diisopropenyl adipate, divinyl adipate, diethyl sebacate, diphenyl sebacate, divinyl sebacate, sebacin Aliphatic dicarboxylic acid derivatives such as diisopropenyl acid, dimethyl phthalate, diphenyl phthalate,
Aromatic dicarboxylic acid derivatives such as divinyl phthalate, dimethyl isophthalate, diphenyl isophthalate, divinyl isophthalate, dimethyl terephthalate, diphenyl terephthalate, divinyl terephthalate, phthalic anhydride, succinic anhydride, tetrahydrophthalic anhydride, hexahydro Polycarboxylic acid anhydrides such as phthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, heptic anhydride, hymic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, methylcyclohexentricarboxylic anhydride, etc. Can be mentioned.

The structure of the polyester obtained in the present invention is as follows:
It is characteristic in that it gives a linear polymer despite having three or more hydroxyl groups deposited in an ester bond. For example, using an example in which sorbitol and divinyl sebacate are used, a linear polyester in which primary alcohols at both ends of a sugar alcohol are selectively esterified is provided as shown in the following formula.

[0014]

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On the other hand, an attempt to obtain a polyester by reacting a polyhydric alcohol other than a sugar alcohol such as glycerin with a carboxylic acid in the presence of a hydrolase (for example, Japanese Patent Application Laid-Open No. 10-195185), In general, it is difficult to obtain a water-soluble polyester, since a branched or gel-like polyester is not obtained.

However, the polyester obtained in the present invention is not only soluble in water containing 50% by volume of methanol in a system using sorbitol as a sugar alcohol and divinyl adipate as a dicarboxylic acid or a dicarboxylic acid derivative. Not soluble in water.
Further, in a system using sorbitol, dicarboxylic acid or divinyl sebacate as a dicarboxylic acid derivative as a sugar alcohol, the polyester of the present invention is soluble in water containing 50% by volume of methanol. There is a feature that is excellent. This means, for example, curable polymers as water-soluble resins, thermosetting resin materials, reactive polymers, coating film forming materials, ink paint materials,
It shows that it is useful as a biocompatible polymer and a biodegradable polymer material.

In the present invention, the reactivity of the hydroxyl groups remaining in the polyester can be used to modify or cure the polyester by, for example, reacting it with isocyanate or epoxy.

The polyester obtained in the present invention may be any of various solvents such as chloroform, tetrahydrofuran (THF),
Dimethylformamide (DMF), dimethylsulfoxide (DM
It is soluble in SO), chlorobenzene, acetone, methyl ethyl ketone, cyclohexanone, ethyl acetate, toluene and xylene, and has excellent handling.

The present invention is characterized by utilizing an ester synthesis reaction catalyzed by lipase. Accordingly, the lipase used in the present invention is not particularly limited as long as it catalyzes an ester synthesis reaction, but preferred examples include genus Pseudomonas, genus Alcaligenes, and Achromobact.
er), lipase obtained from microorganisms such as genus Candida, genus Aspergillus, genus Aspergillus, genus Rhizopus, genus Mucor, lipase obtained from plant seeds, lipase obtained from animal tissues, Further, pancreatin, stearpsin and the like can be mentioned. Among them, it is desirable to use a lipase derived from microorganisms of the genera Pseudomonas, Candida, Aspergillus, and Rhizopus. As a specific example, Pseudomonasfluores
cens), Pseudomonas cepas
ia), Candida anta
rctica), Candidarugos (Candidarugos)
a), Aspergillus niger,
Examples thereof include those derived from Rhizopus delemer and Rhizopus japonicus, and it is particularly preferable to use a lipase derived from Candida antarctica. In the present invention, two or more types of lipases may be used as a mixture, and an enzyme immobilized by a known method may be used to stabilize the enzyme or facilitate recovery after the reaction. It is possible.

In the synthesis of the polyester of the present invention, a solvent can be used if necessary. As the solvent, those that do not hinder the ester synthesis activity of lipase are preferable.
For example, aliphatic hydrocarbon solvents hexane, cyclohexane, heptane, octane, isooctane, aromatic hydrocarbon solvents benzene, toluene, dichlorobenzene, chlorobenzene, anisole, halogenated hydrocarbon solvents chloroform, dichloromethane, dichloroethane, Examples include carbon tetrachloride, ether solvents such as diethyl ether, dioxane, tetrahydrofuran, diisopropyl ether, di-n-butyl ether, polar solvents such as isopropanol, t-amyl alcohol, acetonitrile, and ethyl acetate.

In the synthesis of the polyester of the present invention,
A low-molecular compound is produced as a by-product of the condensation reaction, but there is no problem in using a method of rapidly removing this by-product from the reaction system in order to promote the reaction. 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 present invention, there is no problem even if the lipase is present in a solid state in the reaction system and, therefore, maintains a dispersed state in the reaction system.

In the present invention, the molar ratio of sugar alcohol to dicarboxylic acid or dicarboxylic acid derivative is preferably in the range of dicarboxylic acid or dicarboxylic acid derivative: aliphatic alcohol: fatty acid = 1: 10 to 10: 1. 1: 3 to 3: 1 is desirable. The reaction temperature is preferably -10 to 150 ° C, which is a range that does not inactivate the enzyme, and more preferably 10 to 100 ° C.

In the present invention, the amount of lipase to be added may be appropriately adjusted depending on the ester synthesizing ability of the hydrolase to be used, but is preferably 0.01 to 0.01% of the total amount of sugar alcohol and dicarboxylic acid or dicarboxylic acid derivative.
The content may be set to about 1000% by weight, more preferably 0.1 to 200% by weight.

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

[0026]

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) 2 mL of acetonitrile, 77 mg (0.3 mmol) of divinyl sebacate, 55 mg (0.3 mmol) of sorbitol in a 50 mL eggplant flask, and lipase (from Candida antactica) 10 mg
0 milligrams were added. This was stirred at 60 ° C. for 3 days. After the completion of the reaction, dimethyl sulfoxide was added to the reaction solution to dissolve the product, and then filtered to remove the enzyme. After the filtrate was concentrated under reduced pressure to remove the solvent, water was added to dissolve the unreacted sugar alcohol, and the polymer was recovered by filtration and dried under reduced pressure. Yield 67 mg (yield 64
%). The obtained polymer was a pale yellow powder. GPC
The number average molecular weight (Mn) determined by analysis was 9,800 in terms of polystyrene, and the molecular weight distribution (Mw / Mn) was 2.1. Further, this resin was soluble in chloroform, THF, DMSO, and DMF. When 13C-NMR of the obtained sample was measured, peaks were assigned as follows, and it was confirmed that the sample was a linear polymer. The obtained polymer was soluble in a 50% by volume aqueous methanol solution. 13C-NMR: δ = 175.0 ppm, 173.6 ppm (C9, C7) 71.5 ppm (C3) 71.1 ppm (C5) 69.6 ppm (C4) 69.0 ppm (C2) 66.9 ppm (C1) 66.2 pm (C6) 34.1, 34.0, 29.1, 24.9 ppm (C8) The numbers in parentheses correspond to the numbers in the following chemical formula.

[0027]

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(Examples 2 to 13) In Examples 2 to 13, experiments were performed by changing the corresponding conditions in the operation of Example 1 to the conditions shown in Table 1. The results are shown in Table 1. In addition, the amount of the sugar alcohol used in Examples 10 to 13 was 0.3 mmol. Further, various analyzes confirmed that the polyesters obtained in Examples 2 to 13 were linear polymers, and were soluble in chloroform, THF, DMSO, and DMF.

[0029]

[Table 1]

[0030]

Since the polyester of the present invention has a reactive hydroxyl group, it is useful as a curable polymer, a thermosetting resin material, a reactive polymer, a coating film forming material, and an ink coating material. Further, the polyester is an aliphatic linear polyester having high solubility in water, and is useful as a biocompatible polymer and a biodegradable polymer since a natural product-derived sugar alcohol is used as a raw material.

 ──────────────────────────────────────────────────続 き Continued on front page F-term (reference) 4B064 AD83 CA21 CD07 CD10 CD12 CE01 CE08 CE16 CE20 DA16 4C081 BA16 BA17 CA161 CB021 CC01 4J029 AA01 AB01 AC01 AD01 AE11 CA01 CA02 CA03 CA04 CA05 CA06 CB04A CB04A CB06 CB06 CB06 CB06 CB06 CB06 CB06 CB06 CB06 CC09 CD03 EA02 EA05 FC08 FC29 FC35 FC36 FC38 FC41 GA12 GA13 GA14 GA15 GA17 GA22 GA24 HA01 HB01 HB03A HB04A HB06 JE241

Claims (5)

[Claims] 1. A polyester obtained by reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase. (2) The sugar alcohol is sorbitol, xylitol, mesoerythritol, mannitol, or N-
The polyester according to claim 1, which is methylglucamine. 3. The polyester according to claim 1, which has a number average molecular weight of 800 to 30,000. 4. A method for producing a polyester, comprising reacting a sugar alcohol with a dicarboxylic acid or a dicarboxylic acid derivative in the presence of a lipase. (5) the sugar alcohol is sorbitol, xylitol, mesoerythritol, mannitol, or N-
The method for producing a polyester according to claim 4, which is methylglucamine.