JPH09104721A - Biodegradable polymer, its production and method for accelerating biodegradation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a biodegradable polymer which can be used as a molding material, a moisture-absorbing water-absorbing material, a film-forming material, a compatibilizer, an interface modifier, a pigment dispersion agent or the like by forming a polymer having side chains of a specified structure. SOLUTION: This biodegradable polymer is a polyaddition, polycondensation or addition polymerization type one having a number-average molecular weight of 1,000-1,000,000 and containing a polyalkylene oxide structure represented by formula I (wherein R<1> is H or an alkyl; (n) is 1-4; and (m) is 2-100,000) as a side chain. This polymer is obtained by copolymerizing 20-100wt.% monomer represented by formula II wherein R<2> is H or CH<3> ; A is a direct bond or a (substituted) phenylene; X is O, COO, R<3> O [wherein R<3> is CH2 , CH2 CH2 , OCOR<4> CO, CH2 OCOR<4> CO or CH2 CH2 OCOR<4> CO (wherein R<4> is a direct bond or a 1-7C alkyl]} with other polymerizable vinyl compound or by grafting a compound represented by formula IV [wherein Y is H or an alkali (alkaline earth) metal] onto a polymer having a number-average molecular weight of 1,000-500,000 and having a group represented by formula II (wherein R<5> is H, an alkyl or a halogen) as a side chain.

Description

DETAILED DESCRIPTION OF THE INVENTION

FIELD OF THE INVENTION The present invention has a polyalkylene oxide side chain, a film, a molding material such as plastics, a moisture-absorbing / water-absorbing material, a water-soluble or solvent-free paint,
For film forming materials such as adhesives and inks, or compatibilizers,
The present invention relates to a biodegradable polymer that can be used as an interface modifier, a pigment dispersant, etc., a production method and a biodegradation promoting method thereof.

[0001]

2. Description of the Related Art Molded articles such as plastic films and containers used as packaging materials and agricultural materials, and paints, inks, adhesives, etc. printed or coated on them are discarded by other than the proper processing route. Sometimes. In this case, the product has maintained its shape for many years, causing serious waste pollution. Therefore, it is desired that products that may be discarded outdoors, in fields, rivers, etc. be promptly decomposed by microorganisms in the soil or water. So far,
Polymers containing lactic acid as the main constituent (US Pat 1,995,97
0) shows good biodegradability and absorbability in the body.
In 123, a method for synthesizing a high-molecular weight polymer via a cyclic dimer is shown, and poly (ε-caprolactone) is easily decomposed by microorganisms (Reference:
Polym. Prepr. Am. Chem. Soc. Polym. Chem. Div., 1
3, 629 (1972)), which is already on the market as a biodegradable polymer. Further, in JP-A-3-31333, a biodegradable resin composition consisting of a saponified ethylene / vinyl acetate copolymer and modified starch is examined, and in JP-A-4-189822, a polycondensation of glycol and an aliphatic dicarboxylic acid is conducted. Aliphatic polyesters have been reported. Furthermore, in EP 52,459, many studies on biodegradable polymers have been conducted, such as the fact that random copolymers of hydroxybutyric acid and hydroxyvaleric acid produced in the cells of hydrogen bacteria (Alcaligenes eutrophus) are studied as biodegradable polymers. It is being advanced. However, even if the molded article itself is biodegradable, if the paint or printing ink coating the surface of the molded article is not biodegradable, the degradability of the product is impaired. However, research on biodegradable resins so far has centered on research on molded articles, and at the present time, highly versatile biodegradable resins that can be used for paints and printing inks have not been obtained so far.

On the other hand, regarding the biodegradability of polyalkylene oxide itself, Fisher and Payne, Kawai and Yama
It was known by gata and others (reference: Appl. Microbio
l., 10, 542 (1962), Arch. Microbiol., 46, 125 (198
6)). However, biodegradability was recognized only for those having a hydroxyl group at the terminal, and the biodegradation mechanism was limited to a system in which the terminal was gradually decomposed. On the other hand, Cho
and Okamoto have shown that OH radicals produced by the glucose / glucose oxidase (GOD) system randomly decompose high molecular weight polyethylene oxide (Macromol. Rapid Commun., 15, 629).
(1994)). However, in this method, it can be said that it is difficult to treat a large amount of waste because the conditions of the reaction system are complicated to set. In addition, the polyacetylene oxide alone has a drawback that the usable applications are limited to nonionic surfactants and lubricants.

[0003]

DISCLOSURE OF THE INVENTION As a result of intensive studies to solve the above problems, the present inventors have found that a monomer containing a polyalkylene oxide is copolymerized or a polyalkylene oxide is contained. By grafting side chains, polymers, films, molding materials such as plastics, moisture-absorption / water-absorption materials, water-soluble or solvent-free paints, adhesives, film forming materials such as inks, or compatibilizers, interface modifiers. It has been found that a highly versatile biodegradable polymer that can be used as a substance, a pigment dispersant, etc. can be obtained.
Furthermore, since oxygen in the air autoxidizes polyalkylene oxide to produce peroxide (Ph
arm. Acta Helv., 50, 10 (1975)), the biodegradable polymer can be promoted by heating the biodegradable polymer under constant conditions in air and further adding peroxidase at the time of disposal. The present invention has been accomplished by finding a simple method.

[0004]

Means for Solving the Problems The present invention provides the following formula (1)
The present invention relates to a biodegradable polymer having a number average molecular weight of 1,000 to 1,000,000 selected from a polyaddition type polymer, a polycondensation type polymer and an addition polymerization type polymer having a polyalkylene oxide structure represented by _{- (C n H 2n CH 2} O) m -R 1 (1) ( wherein, R ¹ represents a hydrogen atom or an alkyl group, n 1-4
And m is an integer of 2 to 100,000. )

The present invention relates to the above biodegradable polymer, characterized in that in the above formula (1), R ¹ is a hydrogen atom. The present invention also relates to the above biodegradable polymer, wherein the monomer represented by the following formula (2) is copolymerized with another polymerizable vinyl compound at a blending ratio of 20 to 100% by weight. ^{_{CH 2 = C (R 2)}} -A-X- (C n H 2n CH 2 O) m R 1 (2) ( wherein, R ² is a hydrogen atom or CH _3, R ¹ a hydrogen atom or an alkyl radical, n Is an integer of 1 to 4, m is 2 to 100,
000 integer, A is phenylene group which may have a direct bond or a substituent, X is -O -, - COO- or -R ³
Each represents O-. Here, R ³ is —CH ₂ —, —C
_{H 2 CH 2 -, - O} -CO-R 4 -CO -, - CH 2 -
O-CO-R ⁴ -CO- or -CH ₂ CH ₂ -O-C
Representing the O-R ⁴ -CO-. However, R ⁴ represents a direct bond or an alkyl group having 1 to 7 carbon atoms which may be branched. )

The present invention relates to a method for producing the above biodegradable polymer. The present invention relates to a method for producing a biodegradable polymer, wherein A is a direct bond and X is —COO— in the above formula (2). The present invention also relates to a polymer having a number average molecular weight of 1,000 to 500,000, which has a substituent represented by the following formula (3) on the side chain and is selected from polyaddition type, polycondensation type and addition polymerization type polymers, A—X—R ⁵ (3) (In the formula, A represents a phenylene group which may have a direct bond or a substituent, and X represents —O—, —COO—, or —R ³ O—, respectively. , R ³ is —CH ₂ —, —CH ₂ CH ₂
-, - O-CO-R 4 -CO -, - CH 2 -O-CO-
R ⁴ -CO- or _{-CH 2 CH 2 -O-CO-} R 4 -
Represents CO-. However, R ⁴ is a direct bond or has 1 carbon atom
~ 7 optionally branched alkyl group, R ⁵ represents a hydrogen atom, an alkyl group, or a halogen atom, respectively. The present invention relates to the above biodegradable polymer, wherein a compound having a polyalkylene oxide structure represented by the following formula (4) is grafted. _{YO- (C n H 2n CH 2} O) m -R 1 (4) ( wherein, R ¹ represents a hydrogen atom or an alkyl group, n 1-4
, M is an integer of 2 to 100,000, Y is a hydrogen atom, an alkali metal or an alkaline earth metal. ) The present invention relates to a method for producing the above biodegradable polymer.

Further, the present invention relates to a method for promoting biodegradation, which comprises subjecting the above biodegradable polymer to heat treatment at a temperature of 50 to 200 ° C. in the presence of oxygen. Further, the present invention is
The present invention relates to a method for promoting biodegradation, which comprises subjecting the above biodegradable polymer to heat treatment in the presence of oxygen at a temperature of 50 to 200 ° C. and adding peroxidase.

In the present invention, the polyalkylene oxide structure represented by the general formula (1) has a role of imparting biodegradability to a polymer containing the polyalkylene oxide structure in its side chain, and has a repeating unit of 2 to 100,000. Preferably 2 to 1,0
00. When the number of repeating units is less than 2, peroxyside is not generated even when heat-treated, which is not preferable.
When the amount is more than 1,000, especially 100,000, it is difficult to control the physical properties such as heat resistance and mechanical properties of the obtained polymer, and therefore it is not preferable to contain it in a high ratio. The content of such a polyalkylene oxide structure is preferably 5 to 95%, more preferably 20 to 90%, as a weight fraction with respect to the whole. If it is less than this range, the biodegradability is lowered, which is not preferable. On the other hand, if the amount is more than the above range, it has biodegradability, but it is not preferable because it is difficult to control other physical properties and applications are limited. Further, the terminal has biodegradability with either a hydrogen atom or an alkyl group, but a hydroxyl group increases biodegradability because both biodegradation from the terminal and biodegradation from the polyalkylene glycol structure proceed. preferable.

In the present invention, the polyaddition type, polycondensation type and addition polymerization type polymers containing the polyalkylene oxide structure represented by the general formula (1) in the side chain are represented by the formula (1)
Having a functional group capable of polycondensation with the structure represented by the formula (1) and a polyaddition reaction such as radical polymerization, cationic polymerization, anionic polymerization, or redox polymerization of a monomer having a polymerizable double bond A polymer obtained by a polycondensation reaction of a monomer or an addition polymerization reaction of a monomer having a structure represented by the formula (1) and a functional group capable of addition polymerization such as an epoxy group,

Alternatively, vinyl-based polymers such as polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride, acrylic polymers such as poly (meth) acrylic acid and poly (meth) acrylic acid ester, polystyrene, polybenzyl alcohol, polybenzyl alcohol derivatives , Polybenzyl chloride and other polyaddition type polymers, polyester,
Polyurethane, polyurea, polyamic acid ester,
Examples include polymers obtained by grafting polycondensation polymers such as polyamic acid, polyamide amic, polyamide, and polyimide, addition polymerization polymers such as epoxy resin, with a substituent having a structure represented by the general formula (1). . The number average molecular weight of such a polymer is
1,000 to 1,000,000, preferably 10,
000-500,000 (gel permeation chromatography;
If it is smaller than this, it is not preferable because it is inferior in resistance and mechanical properties, and if it is larger than this, it is not preferable because it is inferior in solubility and processability.

In the present invention, the monomer containing a polyalkylene oxide structure represented by the general formula (2) is used for imparting biodegradability by copolymerizing the monomer. Examples of such a monomer include polyalkylene glycol monovinyl ether-based monomers such as polyethylene glycol monovinyl ether, polypropylene glycol monovinyl ether, polybutylene glycol monovinyl ether, tetra (oxyethylene) vinyl phenyl ether, and methyl tetra (oxy). Ethylene) vinyl phenyl ether, ethyl tetra (oxyethylene)
Vinyl phenyl ether, propyl tetra (oxyethylene) vinyl phenyl ether, n-butyl tetra (oxyethylene) vinyl phenyl ether, n-pentyl tetra (oxyethylene) vinyl phenyl ether, tetra (oxypropylene) vinyl phenyl ether, methyl tetra (oxy Propylene) vinyl phenyl ether, ethyl tetra (oxypropylene) vinyl phenyl ether, propoxy tetra (oxy propylene) vinyl phenyl ether, n-butyl tetra (oxy propylene) vinyl phenyl ether, n-penta xy tetra (oxy propylene) vinyl phenyl ether, poly (Oxyethylene) vinyl phenyl ether, methyl poly (oxyethylene) vinyl phenyl ether, ethyl poly (oxyethylene) Vinyl vinyl ether, poly (oxypropylene) vinyl phenyl ether, methyl poly (oxypropylene) vinyl phenyl ether, ethyl poly (oxypropylene) vinyl phenyl ether, poly (oxyethylene) vinyl benzyl ether, methyl poly (oxyethylene) vinyl benzyl ether , Ethyl poly (oxyethylene) vinyl benzyl ether, poly (oxypropylene) vinyl benzyl ether, methyl poly (oxypropylene) vinyl benzyl ether, ethyl poly (oxypropylene) vinyl benzyl ether, poly (oxyethylene) vinyl phenyl ethyl ether, methyl poly (oxy Ethylene) vinyl phenyl ethyl ether, ethyl poly (oxyethylene) vinyl phenyl ethyl ether, poly (o (Xypropylene) vinyl phenyl ethyl ether, methyl poly (oxypropylene) vinyl phenyl ethyl ether,
Styrene-based monomer having polyalkylene oxide such as ethyl poly (oxypropylene) vinyl phenyl ethyl ether,

Further, tetraethylene glycol (meth)
Acrylate, methoxytetraethylene glycol (meth) acrylate, methoxynonaethylene glycol (meth) acrylate, nonaethylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, propoxytetraethylene glycol (meth) acrylate, n-butoxytetra Ethylene glycol (meth) acrylate, n-pentaxytetraethylene glycol (meth) acrylate, tetrapropylene glycol (meth) acrylate, methoxytetrapropylene glycol (meth) acrylate,
Ethoxytetrapropylene glycol (meth) acrylate, propoxytetrapropylene glycol (meth)
Acrylate, n-butoxytetrapropylene glycol (meth) acrylate, n-pentoxytetrapropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, polypropylene glycol An acrylic monomer having a polyalkylene oxide such as (meth) acrylate may be used.

The other polymerizable vinyl compound used in the present invention is particularly limited because it is used for imparting crosslinking curability to the biodegradable polymer and controlling physical properties such as heat resistance and viscoelasticity. Instead, the compound can be selected according to the purpose. Examples of such a polymerizable vinyl compound include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, and heptyl (meth). ) Acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate , Pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, icosyl (meth) ac (Meth) such as rate, henicosyl (meth) acrylate, docosyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate Acrylic acid derivative,

Styrene, vinyl phenyl pentyl ether, vinyl phenyl hexyl ether, vinyl phenyl heptyl ether, vinyl phenyl octyl ether, vinyl phenyl nonyl ether, vinyl phenyl decyl ether, vinyl phenyl undecyl ether, vinyl phenyl dodecyl ether, vinyl phenyl tridecyl. Ether, vinylphenyl tetradecyl ether, vinylphenyl pentadecyl ether, vinylphenyl hexadecyl ether, vinylphenyl heptadecyl ether, vinylphenyl octadecyl ether, vinylphenyl nonadecyl ether, vinylphenyl eicosyl ether, vinylphenyl heneicosyl ether, Vinyl phenyl docosyl ether, vinyl phenyl methyl butyl Ether, vinyl phenyl methyl pentyl ether, vinyl phenyl methyl hexyl ether, vinyl phenyl methyl heptyl ether, vinyl phenyl methyl octyl ether, vinyl phenyl methyl nonyl ether,
Vinyl phenyl methyl decyl ether, vinyl phenyl methyl undecyl ether, vinyl phenyl methyl dodecyl ether, vinyl phenyl methyl tridecyl ether, vinyl phenyl methyl tetradecyl ether, vinyl phenyl methyl pentadecyl ether,
Vinyl phenyl methyl hexadecyl ether, vinyl phenyl methyl heptadecyl ether, vinyl phenyl methyl octadecyl ether, vinyl phenyl methyl nonadecyl ether, vinyl phenyl methyl eicosyl ether, vinyl phenyl methyl hen eicosyl ether, vinyl phenyl methyl docosyl ether, etc. Styrene derivative,

Isopropenylphenylmethyl butyl ether, isopropenylphenylmethyl pentyl ether, isopropenylphenylmethyl hexyl ether, isopropenylphenylmethyl heptyl ether, isopropenylphenylmethyl octyl ether, isopropenylphenylmethyl nonyl ether,
Isopropenyl phenyl methyl decyl ether, isopropenyl phenyl methyl undecyl ether, isopropenyl phenyl methyl dodecyl ether, isopropenyl phenyl methyl tridecyl ether, isopropenyl phenyl methyl tetradecyl ether, isopropenyl phenyl methyl pentadecyl ether, isopropenyl phenyl methyl Hexadecyl ether, isopropenylphenylmethyl heptadecyl ether,
Isopropenyl derivatives such as isopropenylphenylmethyl octadecyl ether, isopropenylphenylmethyl nonadecyl ether, isopropenylphenylmethyl eicosyl ether, isopropenylphenylmethyl heneicosyl ether, isopropenylphenylmethyl docosyl ether,

N-methylolacrylamide, N-methylolmethacrylamide, N- (methoxymethyl) acrylamide, N- (methoxymethyl) methacrylamide, N- (ethoxymethyl) acrylamide, N-
(Ethoxymethyl) methacrylamide, N- (propoxymethyl) acrylamide, N- (propoxymethyl) methacrylamide, N- (butoxymethyl) acrylamide, N- (butoxymethyl) methacrylamide, N- (pentoxymethyl) acrylamide, N-
Monoalkylol (meth) acrylamides such as (pentoxymethyl) methacrylamide,

N, N-di (methylol) acrylamide, N-methylol-N- (methoxymethyl) methacrylamide, N, N-di (methoxymethyl) acrylamide, N-ethoxymethyl-N-methoxymethylmethacrylamide, N , N-di (ethoxymethyl) acrylamide, N-ethoxymethyl-N-propoxymethylmethacrylamide, N, N-di (propoxymethyl) acrylamide, N-butoxymethyl-N- (propoxymethyl) methacrylamide, N, N -Di (butoxymethyl) acrylamide, N-butoxymethyl-N- (methoxymethyl) methacrylamide, N, N-di (pentoxymethyl) acrylamide, N-methoxymethyl-
Examples thereof include dialkylol (meth) acrylamide such as N- (pentoxymethyl) methacrylamide, vinyl acetate, maleic acid, fumaric acid, itaconic acid, citraconic acid, maleic anhydride, and glucoxyethyl (meth) acrylate.

Of these, for the purpose of imparting crosslinking curability, monoalkylol (meth) acrylamide,
(Meth) acrylic acid derivatives such as dialkyrol (meth) acrylamide, (meth) acrylic acid, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate can be used. Further, in order to improve the thermal characteristics, a polymerizable vinyl compound (B) having an aromatic ring such as a styrene derivative can be used.

In the present invention, the monomer represented by the general formula (2) is 20 to 100% by weight, preferably 25 to 95.
It is preferable to copolymerize with other polymerizable vinyl compound at a blending ratio of wt%. The mixing ratio of monomers is 25, especially 2
If it is less than 0% by weight, the biodegradability is deteriorated, which is not preferable. On the other hand, if it exceeds 95% by weight, it has biodegradability, but it is not preferable because it is difficult to control other physical properties and applications are limited.

The monomer represented by the general formula (2) and the other polymerizable vinyl compound can be polymerized by a known addition reaction method such as radical polymerization, redox polymerization, or ionic polymerization method. Radical polymerization methods are preferred. The solvent used for the polymerization is not particularly limited, and examples thereof include ethyl acetate, benzene, isopropanol, methyl ethyl ketone, water and the like, a single solvent,
Alternatively, a mixed solvent may be used. The polymerization initiator is not particularly limited, but benzoyl peroxide, azobisisobutyronitrile, potassium persulfate and the like are used.
The polymerization temperature is preferably 60 to 100 ° C. Boiling point is 1
It is preferable to use a solvent having a temperature of 00 ° C. or lower because the reaction conditions can be easily controlled as the reflux temperature. The obtained polymer is used as it is for paints, but it may be replaced by solvent such as water, or the solvent used in the polymerization may be distilled off under reduced pressure. The solvent may be removed by a method such as precipitation purification using a solvent or the like.

In the present invention, the polymer having a substituent represented by the general formula (3) in the side chain selected from polyaddition type, polycondensation type and addition polymerization type polymers is polyvinyl acetate,
Vinyl-based polymers such as polyvinyl alcohol and polyvinyl chloride, acrylic-based polymers such as poly (meth) acrylic acid and poly (meth) acrylic acid esters, polyaddition-based polymers such as polystyrene, polybenzyl alcohol and polybenzyl chloride, polyamic acid esters Examples thereof include polycondensation polymers such as polyamic acid and polyamide amic acid. The number average molecular weight of such a polymer is 1,000 to 500,000, preferably 2,000 to 100,000, and if it is smaller than this, resistance and mechanical properties are inferior, which is not preferable, and conversely larger than this. In this case, the reactivity of grafting is lowered, which is not preferable.

In the present invention, the compound containing the polyalkylene oxide structure represented by the general formula (4) is used for grafting the polyalkylene oxide structure onto the polymer having the substituent represented by the general formula (3). Such compounds include ω-methoxytetraethylene glycol, ω-methoxyhexaethylene glycol,
ω-methoxypolyethylene glycol, ω-methoxytetrapropylene glycol, ω-methoxyhexapropylene glycol, ω-methoxypolypropylene glycol, ω-methoxytetrabutylene glycol, ω-methoxyhexabutylene glycol, ω-methoxypolybutylene glycol, and these Alkali metal or
Mention may be made of alkaline earth metal salts. The grafting ratio of the compound containing the polyalkylene oxide structure represented by the general formula (4) onto the polymer having the substituent represented by the general formula (3) depends on the content of the substituent represented by the general formula (3). Although different, the functional group ratio is preferably 1
It is 5 to 100%, more preferably 20 to 95%.
If it is less than this range, the biodegradability is lowered, which is not preferable. On the other hand, if the amount is more than the above range, it has biodegradability, but it is not preferable because it is difficult to control other physical properties and applications are limited.

The biodegradability of the copolymer obtained by the above method of the present invention can be accelerated by heat treatment in the presence of oxygen. As the heating temperature,
50 to 200 ° C., preferably 80 to 150 in the presence of oxygen
° C. At temperatures lower than 80 ° C., especially 50 ° C., peroxides due to oxidation of the polyalkylene oxide structure are less likely to occur, and at treatment temperatures higher than 150 ° C., especially 200 ° C., the oxidative decomposition of the polyalkylene oxide structure becomes remarkable. High energy consumption is not preferable.
The processing time is preferably 30 seconds to 1 hour,
More preferably, it is 1 to 30 minutes. If it is shorter than 1 minute, especially 30 seconds, a sufficient effect cannot be obtained, and conversely, a treatment time of 30 minutes, especially 1 hour or more, is not preferable because of high energy consumption.

The peroxidase used in the present invention promotes biodegradation by decomposition of peroxide generated in the biodegradable polymer having the polyalkylene glycol structure of the present invention in its side chain by heat treatment or oxidation in soil or the like. Used for. The type of peroxidase that can be used for such purpose is not particularly limited, and peroxidases of various origins are all used, but plant-derived, bacteria-derived, and carrier-derived fungi are preferable, and particularly preferable ones. Examples include those derived from horseradish and soybeans. The addition amount thereof is preferably 0.0001 to 10% by weight, more preferably 0.001 to 5% by weight, based on the biodegradable polymer.

The present invention will be described in more detail below by showing examples, but the present invention is not limited thereto. Further, in the examples,% means% by weight unless otherwise specified.

The abbreviations of the following compounds used in Synthesis Examples, Examples and Comparative Examples are shown below. PEG # 280: hexaethylene glycol (Mn = 282) MEPEG # 350: methoxypolyethylene glycol (Mn = 350) (manufactured by Aldrich) PEG # 20,000: polyethylene glycol (Mn = 20,000) (manufactured by E. MERCK) ) PEG4MA: methoxypolyethylene glycol # 230 methacrylate (Shin-Nakamura Chemical Co., Ltd. M-40G) PEG9MA: methoxypolyethylene glycol # 400 methacrylate (Shin-Nakamura Chemical Co., Ltd. M-90G) PE200MA: polyethylene glycol monomethacrylate (NOF CORPORATION) Blemmer PE-200 Co., Ltd. PE350MA: Polyethylene glycol monomethacrylate (NOF CORPORATION Blemmer PE-350) ST350PEG: Methoxypoly (Oki) Ciethylene) # 350 Vinyl benzyl ether (synthetic product) MMA: Methyl methacrylate (Wako Pure Chemicals, special grade reagent) MA: Methacrylic acid (Wako Pure Chemicals, special grade reagent) GEMA: Glucoxyethyl methacrylate (Nippon Seiki) Chemical Co., Ltd. Sucraph GEMA GMA: glycidyl methacrylate (Tokyo Kasei, reagent grade) NMAM: N- (methoxymethyl) acrylamide (Wako Pure Chemical Industries) PVBC: vinylbenzyl chloride / MMA = 6/4 copolymer (synthetic: Mn = 110,00, Mw / Mn = 2.1)

(Examples 1-8, 12, 14) Synthesis of biodegradable polymer 1 In a 500 ml four-necked round bottom flask equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a condenser,
Compounds were compounded in the composition shown in Table 1, and azobisisobutyronitrile (AIBN) was used as an initiator (1% by weight based on the total amount of charged monomers) in an isopropyl alcohol solvent (concentration at the time of charged monomers: 30% by weight). %) And refluxed for 6 hours to give a viscous liquid. When this was allowed to stand at room temperature or below for 1 hour, it was separated into two layers. The upper layer was removed by decantation, the lower layer portion was washed with petroleum ether, and then vacuum dried at 50 ° C. for one day to obtain the target resin. The number average molecular weight (Mn) in terms of styrene of the obtained resin was measured by gel permeation chromatography (Tosoh SC-8020). Table 1 shows the measurement results.

(Examples 9 to 11, 13 and Comparative Example 1) Synthesis of curable biodegradable polymer 2 In a 500 ml four-necked round bottom flask equipped with a stirrer, a nitrogen introducing tube, a temperature sensor, and a condenser,
Compounds were compounded in the composition shown in Table 1, and azobisisobutyronitrile (AIBN) was used as an initiator (1% by weight based on the total amount of charged monomers), and the solvent was in ethyl acetate (concentration when charged with monomers: 30% by weight). %) For 6 hours to obtain a solution containing the objective resin. The number average molecular weight (Mn) in terms of styrene of the obtained resin was measured by gel permeation chromatography (Tosoh SC-8020). Table 1 shows the measurement results. Further, the obtained resin solution is applied on an aluminum plate with a 5 mil applicator,
When heat-treated at 10 ° C for 10 minutes, a transparent film was obtained. Table 2 shows the results of investigations on the physical properties of this coating. For comparison, Table 2 shows Comparative Example 1 as a result of measuring the physical properties of the coating film similarly investigated for a 30% aqueous solution of PEG # 20,000.

(Example 15) Synthesis of biodegradable polymer 3 In a 500 ml four-necked round bottom flask equipped with a stirrer, nitrogen introducing tube, temperature sensor, and condenser,
Tetrahydrofuran: 100 g / MEPEG # 350:
35 g / sodium hydride: 8 g was added, and the mixture was stirred at room temperature. PVBC: 22 g / tetrahydrofuran: 5 here
A 0 g mixed solution was added dropwise, and the mixture was refluxed for 10 hours. Gel permeation chromatography of the obtained resin (Tosoh SC-8
020) to measure the styrene-equivalent number average molecular weight (Mn). Table 1 shows the measurement results. The grafting rate was 70%.

Table 1 Synthesis of biodegradable polymer ────────────────────────────── Example monomer / composition ratio ( Molar ratio) Mn (* 10 ⁴ ) Mw / Mn ────────────────────────────── 1 PEG4MA 16000 2.3 2 PEG9MA 18000 2.1 3 PEG4MA: MMA = 6: 4 12000 2.1 4 PEG9MA: MMA = 6: 4 14000 2.3 5 PE200MA: MMA = 6: 4 29000 2.5 6 PE350MA: MMA = 6: 4 22000 2.5 7 PEG9MA: PE350MA = 9: 1 26000 2.6 8 PEG9MA: PE350MA = 8: 2 28000 2.7 9 PEG9MA: NAMAM = 6: 4 18000 2.3 10 PEG9MA: GMA = 6: 4 19000 2.3 11 PEG9MA: MA = 6: 4 16000 2.1 12 PEG9MA: GEMA = 6: 4 13000 2.4 13 PEG9MA: GEMA: MA = 6: 2: 2 15000 2.1 14 ST350PEG: MMA = 6: 4 21000 2.6 15 PVBC (GRAFT) MEPEG # 350 23000 2.5 ───────────────── ──────────────

Table 2 Results of physical property test of thermosetting biodegradable polymer ─────────────────────────────────── --Examples Monomer / composition ratio (molar ratio) Pencil hardness Solvent resistance ^{* 1} Water resistance ^{* 2} ─────────────────────────── ───────── 9 PEG9MA: NAMAM = 6: 4 H ○ ○ 10 PEG9MA: GMA = 6: 4 H ○ ○ 11 PEG9MA: MA = 6: 4 HB ○ ○ 13 PEG9MA: GEMA: MA = 6 : 2: 2 H ○ ○ Comparative Example 1 PEG # 20,000 4B ○ × ─────────────────────────────────── ─ * 1: Coating residual rate after 50 times of MEK rubbing test ○: 100%, Δ: 50 or more and less than 100, ×: less than 50% (weight ratio) * 2: Coating residual rate after 100 times of water rubbing test ◯: 100%, Δ: 50 or more and less than 100, x: less than 50% (weight ratio)

(Example 16) Biodegradability evaluation test 1 Table 3 shows the biodegradability evaluation results according to the following (Evaluation method 1) investigated for the resins obtained in Examples 1 to 15. Evaluation method 1: Culture test using soil extract bacteria: A sample was dissolved in an inorganic salt medium containing no carbon source and sterilized using an autoclave. Bacteria extracted from soil were inoculated with sterilized water and cultured at 30 ° C. for 1 month. After culturing, an appropriately diluted medium is inoculated on a regular agar medium, the resulting colonies are counted to determine the viable cell count, and the change in viable cell count before and after culturing (Δ viable cell count = viable cell count after culturing ( CFU / ml) / viable cell count before culturing (CFU / m
l)) was used to evaluate biodegradability.

Table 3 Biodegradability evaluation test 1 ───────────────────────────── Example Monomer / composition ratio ( Molar ratio) Evaluation method 1 Δ viable cell count ───────────────────────────── 1 PEG4MA 50 2 PEG9MA 55 3 PEG4MA: MMA = 6: 4 30 4 PEG9MA: MMA = 6: 4 40 5 PE200MA: MMA = 6: 4 100 6 PE350MA: MMA = 6: 4 150 7 PEG9MA: PE350MA = 9: 1 250 8 PEG9MA: PE350MA = 8: 2 1000 9 PEG9MA: NAMAM = 6: 4 → After heat curing ^* 50 10 PEG9MA: GMA = 6: 4 → After heat curing 60 11 PEG9MA: MA = 6: 4 → After heat curing 100 12 PEG9MA: GEMA = 6: 4 500 13 PEG9MA : GEMA: MA = 6: 2: 2 → After heat curing 400 14 ST350PEG: MMA = 6: 4 40 15 PVBC (GRAFT) MEPEG # 350 50 ────────────────── ───────────── *: A sample after heat curing was scraped from an aluminum plate and used as a sample.

(Example 17) Biodegradability evaluation test 2 PEG # 20,000 and the resins obtained in Examples 2, 4, 6 and 7 were evaluated by the methods of the following Evaluations 2 and 3 to evaluate biodegradability. The results are shown in Table 5. Evaluation method 2; glucose / glucose oxidase (GO
D) Enzymatic degradation: Cho and Okamoto have shown that high molecular weight polyethylene oxide is randomly degraded by OH radicals generated by glucose / GOD system (Macromol. Rapid Commun., 15, 629).
(1994)). Enzymatic degradation of the sample was performed using this method. GOD is derived from Aspergillus niger and has a specific activity of 186u
It was nits / mg. Reaction is 100 mM acetate buffer (pH 5.6)
The concentration of GOD, glucose and ferrous chloride as a reducing agent was 10 mg / L, 2.5 × 10 ^-2 mol / L and 9.6 ×, respectively.
It was set to 10 ^-5 mol / L. The sample concentration was 10.0% by weight. The enzyme reaction is performed in a double cylinder type rheometer kept at 25 ° C, and the viscosity (complex viscosity) decreases (Δ viscosity = viscosity after enzyme reaction (P) / viscosity before enzyme reaction (P)) Judged the sex. By the way, Cho and Okamoto admitted the decomposition of polyethylene oxide from the decrease in the viscosity average molecular weight obtained from the viscosity measured by a rheometer.

Evaluation method 3: Decomposition by peroxidase (POD): In order to accelerate the auto-oxidation of polyalkylene glycol, in the presence of 1.0 × 10 ⁻⁴ M copper sulfate, 2 at 50 ° C.
Using the sample heated for 4 hours, POD was used to decompose the peroxide generated in the sample for enzymatic decomposition. The POD used is derived from horseradish and has a specific activity of 621uni.
It was ts / mg. Reaction is 100 mM phosphate buffer (pH 6.8)
The enzyme concentration was 1.6 mg / L. Also, pyrogallol was added as a hydrogen donor so that the concentration was 20 mM. The degradability of the sample was evaluated in the same manner as in the case of glucose / GOD.

Table 4 Biodegradability evaluation test 2 ─────────────────────────────────── Example Single dose Body-composition ratio (molar ratio) Evaluation method 2 Evaluation method 3 Δ viscosity Δ viscosity ───────────────────────────────── ── 2 PEG9MA 0.67 0.58 4 PEG9MA: MMA = 6: 4 0.80 0.75 6 PE350MA: MMA = 6: 4 0.75 0.60 7 PEG9MA: PE350MA = 9: 1 0.64 0.52 Comparative Example 2 PEG # 20,000 0.21 0.15 ────── ────────────────────────────

(Example 18) Biodegradability evaluation test 3 PEG # 20,000 and untreated resins obtained in Examples 2, 4, 6 and 7 and 10 at 100 ° C
Table 4 shows the results of biodegradability evaluation conducted by the methods 4 to 6 described below for the heat-treated products for minutes. Evaluation method 4: Biodegradability test using compost: A sample was added to a compost derived from broad-leaved bark, and the temperature was 30 ° C. and the relative humidity was 1
It was cultured for 1 month in a constant temperature and humidity chamber of 00%. After culturing, TH
The sample is extracted using F, the molecular weight is measured by GPC,
The biodegradability was judged from the decrease in the peak area derived from the sample before and after the culture. In addition, the adsorption of the sample by the compost was not observed, and the reduction of the peak area was not observed in the compost sterilized by the autoclave. Moreover, the molecular weight measured by GPC is a value converted into styrene.

Evaluation method 5; Biodegradability test using glucose / GOD-added compost: GOD, glucose and ferrous chloride were added to the compost shown in Evaluation method 4,
The biodegradability was evaluated in the same manner as in Evaluation method 4. GOD,
Glucose and ferrous chloride were added to the water contained in the compost so as to have the concentrations shown in Evaluation method 2. Evaluation method 6: Biodegradability test using compost to which POD was added: POD was added to the compost shown in Evaluation method 4, and biodegradability was evaluated by the same method as in Evaluation method 4. PO
D was added to the water contained in the compost so as to have the concentration shown in Evaluation method 4. No hydrogen donor was added.

Table 5 Biodegradability evaluation test 3 ──────────────────────────────────── Example Polymer / composition ratio (molar ratio) Evaluation method 4 Evaluation method 5 Evaluation method 6 Δ Peak area Δ Peak area Δ Peak area ───────────────────────── ──────────── 2 PEG9MA untreated 0.97 0.64 0.70 heat treated 0.75 0.55 0.50 4 PEG9MA: MMA = 6: 4 untreated 0.98 0.78 0.83 heat treated 0.80 0.72 0.65 6 PE350MA: MMA = 6: 4 Untreated 0.65 0.38 0.50 Heat treated 0.45 0.36 0.32 7 PEG9MA: PE350MA = 9: 1 Untreated 0.76 0.50 0.53 Heat treated 0.60 0.42 0.40 Comparative Example 2 PEG # 20,000 Untreated 0.95 0.50 0.55 Heat treated 0.80 0.48 0.46 ────── ───────────────────────────── (Δ peak area = peak area after culture / peak area before culture)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication C08F 299/02 MRS C08F 299/02 MRS C08G 65/32 NQH C08G 65/32 NQH ZAB ZAB C08J 11 / 06 ZAB C08J 11/06 ZAB (72) Inventor Kogo Higo 2-33 Kyobashi, Chuo-ku, Tokyo Toyo Inki Manufacturing Co., Ltd.

Claims (9)

[Claims] 1. A number average molecular weight of 1,000 selected from polyaddition-type, polycondensation-type, and addition-polymerization-type polymers containing a polyalkylene oxide structure represented by the following formula (1) in the side chain.
A biodegradable polymer that is ~ 1,000,000. _{- (C n H 2n CH 2} O) m -R 1 (1) ( wherein, R ¹ represents a hydrogen atom or an alkyl group, n 1-4
And m is an integer of 2 to 100,000. ) 2. The biodegradable polymer according to claim ¹ , wherein R ¹ in the above formula (1) is a hydrogen atom. 3. A monomer represented by the following formula (2)
The biodegradable polymer according to claim 1 or 2, which is copolymerized with another polymerizable vinyl compound at a blending ratio of 100% by weight. ^{_{CH 2 = C (R 2)}} -A-X- (C n H 2n CH 2 O) m R 1 (2) ( wherein, R ² is a hydrogen atom or CH _3, R ¹ is a hydrogen atom or an alkyl group, n is an integer of 1 to 4, m is 2 to 10
An integer of 10,000, A is a phenylene group which may have a direct bond or a substituent, and X is -O-, -COO- or-.
It represents R ³ O-respectively. Here, R ³ is —CH ₂ —,
_{-CH 2 CH 2 -, - O} -CO-R 4 -CO -, - CH
₂ -O-CO-R ⁴ -CO- or -CH ₂ CH ₂ -O
It represents the -CO-R ⁴ -CO-. However, R ⁴ represents a direct bond or an alkyl group having 1 to 7 carbon atoms which may be branched. ) 4. A method for producing the biodegradable polymer according to claim 3. 5. In the above formula (2), A is a direct bond and X is —COO—.
A method for producing the biodegradable polymer described. 6. A polymer having a number average molecular weight of 1,000 to 500,000, which has a substituent represented by the following formula (3) selected from polyaddition type, polycondensation type and addition polymerization type polymers in its side chain, A—X—R ⁵ (3) (In the formula, A represents a phenylene group which may have a direct bond or a substituent, and X represents —O—, —COO— or —R ³ O—, respectively. , R ³ is —CH ₂ —, —CH ₂ C
_{H 2 -, - O-CO} -R 4 -CO -, - CH 2 -O-C
O-R ⁴ -CO- or _{-CH 2 CH 2 -O-CO-} R
Represents ^4- CO-. However, R ⁴ is a direct bond or an alkyl group having 1 to 7 carbon atoms which may be branched, and R ⁵ is a hydrogen atom, an alkyl group or a halogen atom, respectively. The method for producing a biodegradable polymer according to claim 1 or 2, wherein a compound having a polyalkylene oxide structure represented by the following formula (4) is grafted. _{YO- (C n H 2n CH 2} O) m -R 1 (4) ( wherein, R ¹ represents a hydrogen atom or an alkyl group, n 1-4
, M is an integer of 2 to 100,000, Y is a hydrogen atom, an alkali metal or an alkaline earth metal. ) 7. The method for producing the biodegradable polymer according to claim 6. 8. A method for promoting biodegradation, which comprises heat-treating the biodegradable polymer according to claim 1 or 2 at a temperature of 50 to 200 ° C. in the presence of oxygen. 9. A method for promoting biodegradation, which comprises subjecting the biodegradable polymer according to claim 1 or 2 to heat treatment in the presence of oxygen at a temperature of 50 to 200 ° C. and adding peroxidase. [0000]