CN115210271A

CN115210271A - N-substituted maleimide polymer and process for producing the same

Info

Publication number: CN115210271A
Application number: CN202180017130.4A
Authority: CN
Inventors: 山口稔; 加原浩二
Original assignee: Nippon Shokubai Co Ltd
Current assignee: Nippon Shokubai Co Ltd
Priority date: 2020-04-01
Filing date: 2021-03-25
Publication date: 2022-10-18
Anticipated expiration: 2041-03-25
Also published as: WO2021200540A1; JP7515995B2; CN115210271B; JP2024099620A; KR20220131537A; JPWO2021200540A1; TW202146497A

Abstract

The purpose of the present invention is to provide a method for producing an N-substituted maleimide polymer, which can obtain a polymer in which thermal coloration is significantly suppressed when a polymer is produced using an N-substituted maleimide monomer and glycidyl (meth) acrylate. The present invention relates to a method for producing an N-substituted maleimide polymer, comprising the steps of: a step (I-2) for obtaining a base polymer by polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b); and a step (I-3) of reacting the base polymer with glycidyl (meth) acrylate having a chlorine content of 0.01 to 0.3 mass% to obtain an N-substituted maleimide polymer having a double bond in a side chain.

Description

N-substituted maleimide polymer and process for producing the same

Technical Field

The present invention relates to a method for producing an N-substituted maleimide-based polymer and an N-substituted maleimide-based polymer obtained by the production method. More specifically, the present invention relates to an N-substituted maleimide polymer which can suppress coloring of a cured product due to heat, and a method for producing the same.

Background

The N-substituted maleimide polymer is obtained by polymerizing a monomer component containing an N-substituted maleimide monomer such as N-benzylmaleimide or N-phenylmaleimide. Since such a maleimide polymer is generally high in glass transition temperature and excellent in heat resistance, it is widely used as an optical material, an electric/electronic material, and the like.

In addition, it is known that a polymerizable double bond is introduced into a side chain of a polymer in order to improve the crosslinkability and the crosslinking density of the polymer. Such a polymer having a polymerizable double bond in a side chain can be obtained, for example, by the following method: a method in which a monomer component containing a monomer having an acid group is polymerized to obtain a polymer as a base, and a compound having an epoxy group and a polymerizable double bond is subjected to an addition reaction with the polymer to introduce the polymerizable double bond into the polymer; a method in which a monomer component containing a compound having an epoxy group and a polymerizable double bond is polymerized to obtain a polymer as a base, and a compound having an acid group and a polymerizable double bond is reacted with the polymer to introduce a polymerizable double bond into the polymer; and the like. In the case of producing such a polymer having a polymerizable double bond in a side chain, glycidyl (meth) acrylate (glycidyl acrylate and/or glycidyl methacrylate) is used as one of the compounds having an epoxy group and a polymerizable double bond.

For example, patent document 1 describes a photosensitive resin composition for color filters, which contains a carboxyl group-containing radical polymerizable copolymer having an ethylenically unsaturated double bond, and the following methods are described as methods for obtaining the radical polymerizable copolymer: a copolymer is obtained by using an N-substituted maleimide compound and an unsaturated carboxylic acid compound such as (meth) acrylic acid (acrylic acid and/or methacrylic acid) as monomer components, and an epoxy group-containing ethylenically unsaturated compound is reacted with the copolymer.

Documents of the prior art

Patent document

Patent document 1: japanese unexamined patent publication No. 2012-32772

Disclosure of Invention

Problems to be solved by the invention

However, a polymer obtained by using glycidyl (meth) acrylate has a problem that it is easily colored by heat due to its constitution. In particular, when glycidyl (meth) acrylate is mixed with an N-substituted maleimide monomer or a polymer containing a structural unit derived from an N-substituted maleimide monomer and heated, there is a problem that the resulting cured product is significantly colored by heat (thermal coloring). In the case where it is desired to use an N-substituted maleimide-based polymer for the production of a light-colored or transparent product, such coloring becomes a great problem.

In view of the above-described situation, an object of the present invention is to provide a method for producing an N-substituted maleimide-based polymer, which can produce a polymer in which thermal coloration is significantly suppressed, when the polymer is produced using an N-substituted maleimide monomer and glycidyl (meth) acrylate.

Means for solving the problems

The present inventors have conducted various studies to solve the above-mentioned problems and have found that a method for producing a polymer using glycidyl (meth) acrylate and an N-substituted maleimide monomer contains chlorine as an impurity, and this chlorine promotes thermal oxidation of a maleimide group, thereby thermally coloring the obtained polymer. The present inventors have also found that an N-substituted maleimide-based polymer having a double bond in a side chain, in which heat discoloration is significantly suppressed, can be obtained by using glycidyl (meth) acrylate having a chlorine content within a predetermined range, for example, by using glycidyl (meth) acrylate having a chlorine content adjusted within a predetermined range, and have completed the present invention.

That is, the present invention relates to a method for producing an N-substituted maleimide-based polymer, comprising the steps of: a step (I-2) for polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b) to obtain a base polymer; and a step (I-3) of reacting the base polymer with glycidyl (meth) acrylate having a chlorine content of 0.01 to 0.3 mass% to obtain an N-substituted maleimide polymer having a double bond in a side chain.

The process for producing an N-substituted maleimide-based polymer preferably further comprises the following step (I-1) before the step (I-2): the glycidyl (meth) acrylate is purified so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

The present invention also relates to a method for producing an N-substituted maleimide polymer, comprising the steps of: a step (II-2) for obtaining a base polymer by polymerizing monomer components comprising an N-substituted maleimide monomer (a) and glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass%; and (II-3) reacting the unsaturated carboxylic acid monomer (b) with the base polymer to obtain an N-substituted maleimide polymer having a double bond in a side chain.

The method for producing an N-substituted maleimide-based polymer preferably further comprises the following step (II-1) before the step (II-2): the glycidyl (meth) acrylate is purified so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

The method for producing an N-substituted maleimide-based polymer preferably further comprises the following step (II-4) after the step (II-3): reacting a polybasic acid or a polybasic acid anhydride with the N-substituted maleimide-based polymer having a double bond in a side chain.

In the method for producing an N-substituted maleimide-based polymer, the amount of residual chlorine in the N-substituted maleimide-based polymer is preferably 100ppm to 2000ppm based on the total amount of the N-substituted maleimide monomer (a) and glycidyl (meth) acrylate.

The present invention also relates to an N-substituted maleimide-based polymer comprising a structural unit (a) derived from an N-substituted maleimide monomer and a structural unit (B) represented by the following general formula (B1), (B2) or (B3), wherein the structural unit (B) contains a structure derived from glycidyl (meth) acrylate, and the amount of residual chlorine in the N-substituted maleimide-based polymer is 100ppm to 2000ppm based on the total mass of the N-substituted maleimide monomer which is a raw material for the polymer and which provides the structural unit (a) and the glycidyl (meth) acrylate which provides the structural unit (B).

[ solution 1]

(in the general formula (B1), R ¹ And R ³ The same or different, represents a hydrogen atom or a methyl group. R ² Represents a divalent linking group. a is 0 or 1.

In the general formula (B2), R ⁴ Represents a hydrogen atom or a methyl group. R ⁵ Represents an ethylenically unsaturated bond-containing group.

In the general formula (B3), R ⁶ Represents a hydrogen atom or a methyl group. R is ⁷ Represents an ethylenically unsaturated bond-containing group. X represents a divalent hydrocarbon group. )

The acid value of the N-substituted maleimide polymer is preferably from 20mgKOH/g to 200mgKOH/g.

The N-substituted maleimide polymer preferably has a double bond equivalent of 300 to 3000 g/equivalent.

The present invention also relates to a curable resin composition comprising the above-mentioned N-substituted maleimide-based polymer and a polymerizable compound.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, an N-substituted maleimide-based polymer having a double bond in a side chain, in which thermal coloration is significantly suppressed, can be suitably obtained. The N-substituted maleimide-based polymer of the present invention can be suitably used as an optical material, an electric/electronic material, or the like.

Detailed Description

The present invention will be described in detail below.

In addition, an embodiment in which 2 or more of the preferred embodiments of the present invention described below are combined is also a preferred embodiment of the present invention.

In the present specification, "(meth) acrylic" means "acrylic" and "methacrylic" and "(meth) acrylate" means "acrylate" and "methacrylate".

Process for producing 1.N-substituted maleimide polymer

The present invention relates to a method (I) for producing an N-substituted maleimide polymer, comprising the steps of: a step (I-2) for obtaining a base polymer by polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b); and a step (I-3) of reacting the base polymer with glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass% to obtain an N-substituted maleimide polymer having a double bond in a side chain.

The present invention also relates to a method (II) for producing an N-substituted maleimide polymer, comprising the steps of: a step (II-2) for obtaining a base polymer by polymerizing monomer components comprising an N-substituted maleimide monomer (a) and glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass%; and (II-3) reacting the unsaturated carboxylic acid monomer (b) with the base polymer to obtain an N-substituted maleimide polymer having a double bond in a side chain.

In both of the processes (I) and (II) for producing an N-substituted maleimide polymer of the present invention, glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass% is used. The reason why the thermal coloration of the resulting polymer can be significantly suppressed by using glycidyl (meth) acrylate whose chlorine content is adjusted to 0.01 to 0.3 mass% is presumed to be as follows. That is, it is considered that the generation of the coloring matter substance is remarkably suppressed by setting the residual chlorine contained in the glycidyl (meth) acrylate to a predetermined range amount, because the chlorine contained as an impurity in the glycidyl (meth) acrylate generates hydrogen chloride and hypochlorous acid upon heating, the generation of the amine from the N-substituted maleimide is promoted, and the generated amine is oxidized by an oxidizing substance such as hypochlorous acid.

In the method for producing an N-substituted maleimide-based polymer according to the present invention, an N-substituted maleimide-based polymer having a double bond in a side chain can be finally obtained. By having a double bond in the side chain, the crosslinking property of the N-substituted maleimide-based polymer is improved and the crosslinking density can be increased.

The double bond refers to a polymerizable double bond, i.e., a carbon-carbon double bond, and examples thereof include a (meth) acryloyl group, a vinyl group, an allyl group, and a methallyl group.

The following will describe in detail the processes (I) and (II) for producing the N-substituted maleimide-based polymer of the present invention.

1-1. Production method (I)

< Process (I-2) >

The production method (I) comprises the following step (I-2): the base polymer (also referred to as "base polymer 1") is obtained by polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b).

The method of obtaining the base polymer 1 by polymerizing the monomer components including the monomers (a) and (b) is not particularly limited, and examples thereof include known polymerization methods such as bulk polymerization, solution polymerization, and emulsion polymerization. Among them, solution polymerization is preferable in terms of being industrially advantageous and facilitating the structure adjustment such as molecular weight. In addition, as the polymerization mechanism of the monomer component, a polymerization method based on a mechanism such as radical polymerization, anion polymerization, cation polymerization, coordination polymerization, or the like can be used, and a polymerization method based on a radical polymerization mechanism is preferable from the viewpoint of industrial advantage.

The molecular weight of the base polymer 1 obtained by polymerizing the monomer components can be controlled by adjusting the amount or kind of the polymerization initiator, the polymerization temperature, the kind or amount of the chain transfer agent, and the like.

Examples of the polymerization initiator include peroxides and azo compounds generally used as polymerization initiators, such as cumene hydroperoxide, dicumyl hydroperoxide, di-t-butyl peroxide, lauroyl peroxide, benzoyl peroxide, t-butyl peroxyisopropylcarbonate, t-butyl peroxy2-ethylhexanoate, t-amyl peroxy2-ethylhexanoate, azobisisobutyronitrile, 1' -azobis (cyclohexanecarbonitrile), 2' -azobis (2, 4-dimethylvaleronitrile), dimethyl 2,2' -azobis (2-methylpropionate), hydrogen peroxide, and persulfate.

The chain transfer agent preferably includes a compound having a mercapto group such as mercaptocarboxylic acids, mercaptocarboxylic acid esters, alkylmercaptoalcohols, mercaptoalcohols, aromatic thiols, mercaptoisocyanurates, etc., more preferably includes alkylmercaptoalcohols, mercaptocarboxylic acids, mercaptocarboxylic acid esters, and further preferably includes n-dodecylmercaptan and mercaptopropionic acid.

The solvent used in the above polymerization is not particularly limited, and examples thereof include: monohydric alcohols such as methanol, ethanol, isopropanol, n-butanol, and sec-butanol; polyhydric alcohols such as ethylene glycol and propylene glycol; ethers such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and 3-methoxybutyl acetate; aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; chloroform; dimethyl sulfoxide; dimethyl carbonate, and the like.

The polymerization initiator, the chain transfer agent and the solvent may be used alone in 1 kind or in combination of 2 or more kinds. In addition, the amount of them used may be appropriately set.

The polymerization temperature may be appropriately set according to the kind and amount of the monomer to be used and the kind and amount of the polymerization initiator, and is, for example, preferably 50 to 200 ℃, and more preferably 80 to 120 ℃.

The polymerization time may be appropriately set, and is, for example, preferably 1 to 12 hours, and more preferably 3 to 8 hours.

The mixing of the monomer components is not particularly limited, and may be appropriately performed according to the desired N-substituted maleimide-based polymer, and the total amount of the monomers (a) and (b) may be mixed at the same time, or the monomer (b) or (a) may be added little by little to the total amount of the monomers (a) or (b) and mixed.

After the base polymer 1 is obtained by polymerizing the monomer components, it is possible to use the base polymer 1 after removing volatile components from the polymerization reaction liquid (polymer solution) and separating the base polymer 1, or it may be used in a solution state without separation, and it is preferable to use the base polymer 1 in a solution state without separation from the viewpoint of cost and the like as an industrial use.

Next, the monomer components used for producing the N-substituted maleimide-based polymer will be described. By polymerizing monomer components including each monomer, a copolymer having a structural unit derived from each monomer can be obtained.

(N-substituted maleimide monomer (a))

Examples of the N-substituted maleimide monomer (a) include compounds represented by the following general formula (a).

[ solution 2]

(wherein R is ⁸ Represents a monovalent hydrocarbon group having 1 to 30 carbon atoms with or without a substituent. )

In the general formula (a), R ⁸ Is a monovalent hydrocarbon group having 1 to 30 carbon atoms, which may have a substituent. The monovalent hydrocarbon group preferably has 1 to 20 carbon atoms, and more preferably 6 to 12 carbon atoms.

Examples of the hydrocarbon group include a chain or ring-shaped aliphatic hydrocarbon group and an aromatic hydrocarbon group.

The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, but is preferably a saturated aliphatic hydrocarbon group.

As the chain-like saturated aliphatic hydrocarbon group, examples thereof include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, sec-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, 2-methylpentyl group, 3-methylpentyl group, 2-dimethylbutyl group, 2, 3-dimethylbutyl group, heptyl group, 2-methylhexyl group, 3-methylhexyl group, 2-dimethylpentyl group, 2, 3-dimethylpentyl group, 2, 4-dimethylpentyl group, 3-ethylpentyl group, 2, 3-trimethylbutyl group, octyl group straight-chain or branched alkyl groups such as methylheptyl, dimethylhexyl, 2-ethylhexyl, 3-ethylhexyl, trimethylpentyl, 3-ethyl-2-methylpentyl, 2-ethyl-3-methylpentyl, 2, 3-tetramethylbutyl, nonyl, methyloctyl, 3, 7-dimethyloctyl, dimethylheptyl, 3-ethylheptyl, 4-ethylheptyl, trimethylhexyl, 3-diethylpentyl, decyl, undecyl and dodecyl.

Among them, an alkyl group having 1 to 30 carbon atoms is preferable, an alkyl group having 1 to 20 carbon atoms is more preferable, and an alkyl group having 1 to 12 carbon atoms is even more preferable.

Examples of the cyclic aliphatic hydrocarbon group include: monocyclic alicyclic hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl and cyclododecyl; polycyclic alicyclic hydrocarbon groups such as dicyclopentyl, norbornyl and adamantyl.

Among them, a monocyclic or polycyclic alicyclic hydrocarbon group having 3 to 30 carbon atoms is preferable, a monocyclic or polycyclic alicyclic hydrocarbon group having 3 to 18 carbon atoms is more preferable, and a monocyclic alicyclic hydrocarbon group having 6 to 12 carbon atoms is even more preferable.

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, a benzyl group, and a phenethyl group. Among them, an aromatic hydrocarbon group having 6 to 30 carbon atoms is preferable, and an aromatic hydrocarbon group having 6 to 12 carbon atoms is more preferable.

The above hydrocarbon group may have a substituent. Examples of the substituent include an alkyl group, an aryl group, a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, and an aryloxy group.

Specific examples of the N-substituted maleimide monomer include N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-t-butylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, N-octylmaleimide, N-2-ethylhexylmaleimide, N-decylmaleimide, N-laurylmaleimide, N-tetradecylmaleimide, N-stearylmaleimide, N-2-decyltetradecyltrimethylmaleimide, N-phenylmaleimide, N-benzylmaleimide, N-naphthylmaleimide, N-chlorophenylmaleimide, N-methylphenylmaleimide, N-hydroxyethylmaleimide, N-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, N-carboxyphenylmaleimide, N-nitrophenylmaleimide, N-tribromophenylmaleimide, N ' -o-phenylenebismaleimide, N ' -m-phenylenebismaleimide, and N, N ' -p-phenylenebismaleimide. Among these, N-benzylmaleimide, N-phenylmaleimide and N-cyclohexylmaleimide are preferable, N-benzylmaleimide and N-cyclohexylmaleimide are more preferable, and N-benzylmaleimide is even more preferable, from the viewpoints of copolymerizability with the N-vinylamide monomer and heat resistance. In particular, N-benzylmaleimide is suitably used in applications where thermal coloration resistance is strongly required, and N-phenylmaleimide is suitably used in applications where affinity with organic fine particles or inorganic fine particles is strongly required.

Examples of the N-benzylmaleimide include: benzyl maleimide; alkyl-substituted benzylmaleimides such as p-methylbenzylmaleimide and p-butylbenzylmaleimide; phenolic hydroxyl-substituted benzylmaleimides such as p-hydroxybenzylmaleimide; halogen-substituted benzylmaleimides such as o-chlorobenzylmaleimide, o-dichlorobenzylmaleimide and p-dichlorobenzylmaleimide; and the like.

The N-substituted maleimide monomer (a) may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Among them, the above-mentioned N-substituted maleimide monomer (a) is preferably N-benzylmaleimide and N-phenylmaleimide. By combining these two types, the dispersion stability of the pigment may be improved, or the surface hardness of the cured film may be improved.

The mass ratio of N-benzylmaleimide to N-phenylmaleimide is preferably 95/5 to 5/95, more preferably 10/90 to 90/10.

The proportion of N-benzylmaleimide when N-phenylmaleimide is used as a main component as the N-substituted maleimide monomer (a) is preferably 1 to 30 parts by mass, more preferably 1 to 20 parts by mass, still more preferably 1 to 10 parts by mass, most preferably 1 to 5 parts by mass, relative to 100 parts by mass of N-phenylmaleimide.

The amount of N-benzylmaleimide to be used is preferably 0.5 to 10 mass%, more preferably 0.5 to 5 mass%, still more preferably 0.5 to 3 mass%, particularly preferably 0.5 to 2 mass%, most preferably 0.5 to 1.8 mass%, based on 100 mass% of the total monomer components.

By setting the content in the above range, the affinity and dispersibility with organic fine particles such as pigments and inorganic fine particles such as quantum dots and silica can be improved.

(unsaturated carboxylic acid monomer (b))

Examples of the unsaturated carboxylic acid monomer (b) include compounds having a carboxyl group and/or a carboxylic anhydride group and a polymerizable double bond.

Examples of the polymerizable double bond include a (meth) acryloyl group, a vinyl group, an allyl group, and a methallyl group. Among them, (meth) acryloyl groups are preferable.

Specific examples of the unsaturated carboxylic acid monomer include: unsaturated monocarboxylic acids such as (meth) acrylic acid, crotonic acid, cinnamic acid, and vinylbenzoic acid; unsaturated polycarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid; chain-extended unsaturated long-chain monocarboxylic acids between unsaturated groups such as succinic acid mono-2- (2-acryloyloxy) hydroxyethyl alcohol and succinic acid mono-2- (2-methacryloyloxy) hydroxyethyl alcohol and carboxyl groups; unsaturated acid anhydrides such as maleic anhydride and itaconic anhydride; and the like. Among these, unsaturated monocarboxylic acids are preferable, and (meth) acrylic acid is more preferable, from the viewpoint of versatility, availability, and the like.

The unsaturated carboxylic acid monomer (b) can be used alone in 1, can also be used in 2 or more combination.

(monomer (c) copolymerizable with the above-mentioned monomer (a) and monomer (b))

The monomer component for producing the base polymer 1 may further contain a monomer (c) copolymerizable with the monomer (a) and the monomer (b) in addition to the monomer (a) and the monomer (b).

The monomer (c) is not particularly limited as long as it is copolymerizable with the monomers (a) and (b), and examples thereof include the following monomers. These can be used alone in 1, also can be used in 2 or more combinations.

Hydroxyl group-containing monomers such as hydroxyalkyl (meth) acrylates including 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 2, 3-hydroxypropyl (meth) acrylate;

methyl (meth) acrylate, ethyl (meth) acrylate, N-propyl (meth) acrylate, isopropyl (meth) acrylate, N-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, N-pentyl (meth) acrylate, sec-pentyl (meth) acrylate, tert-pentyl (meth) acrylate, N-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, tridecyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, benzyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, N-dimethylaminoethyl (meth) acrylate, 1, 4-dioxaspiro [4,5] decan-2-ylmethacrylic acid, (meth) acryloylmorpholine, 4- (meth) acryloyloxymethyl-2-methyl-2-ethyl-1, 3-dioxolane, 4- (meth) acryloyloxymethyl-2-methyl-2-isobutyl-1, 3-dioxolane, 4- (meth) acryloyloxy-2-methyl-2-isobutyl-1, 3-dioxolane, (meth) acrylates such as 4- (meth) acryloyloxymethyl-2-methyl-2-cyclohexyl-1, 3-dioxolane and 4- (meth) acryloyloxymethyl-2, 2-dimethyl-1, 3-dioxolane;

alicyclic (meth) acrylates such as cyclohexyl (meth) acrylate, cyclohexylmethyl (meth) acrylate, isobornyl (meth) acrylate, 1-adamantyl (meth) acrylate, (3, 4-epoxycyclohexyl) methyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tricyclodecanyl methacrylate, dimethyltricyclodecane di (meth) acrylate, pentacyclopentadecane dimethanol di (meth) acrylate, cyclohexane dimethanol di (meth) acrylate, norbornane dimethanol di (meth) acrylate, terpene-1, 8-diol di (meth) acrylate, terpene-2, 8-diol di (meth) acrylate, terpene-3, 8-diol di (meth) acrylate, bicyclo [2.2.2] -octane-1-methyl-4-isopropyl-5, 6-dimethylol di (meth) acrylate and the like;

epoxy group-containing monomers other than glycidyl (meth) acrylate such as β -methylglycidyl (meth) acrylate, β -ethylglycidyl (meth) acrylate, vinylbenzyl glycidyl ether, allyl glycidyl ether, (3, 4-epoxycyclohexyl) methyl (meth) acrylate, and vinylepoxycyclohexane;

(meth) acrylamides such as N, N-dimethyl (meth) acrylamide and N-methylol (meth) acrylamide; macromonomers having a (meth) acryloyl group at one end of a polymer molecular chain, such as polystyrene, polymethyl (meth) acrylate, polyethylene oxide, polypropylene oxide, polysiloxane, polycaprolactone, and polycaprolactam; conjugated dienes such as 1, 3-butadiene, isoprene and chloroprene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate and vinyl benzoate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, 2-hydroxyethyl vinyl ether, and 4-hydroxybutyl vinyl ether; n-vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylimidazole, N-vinylmorpholine and N-vinylacetamide; aromatic vinyls such as styrene, vinyltoluene, α -methylstyrene, xylene, methoxystyrene and ethoxystyrene; unsaturated isocyanates such as isocyanatoethyl (meth) acrylate and allyl isocyanate; α - (unsaturated alkoxyalkyl) acrylate monomers such as α -allyloxymethylacrylic acid, α -allyloxymethyl methacrylate ethyl ester, α -allyloxymethyl acrylate n-propyl ester, α -allyloxymethyl acrylate isopropyl ester, α -allyloxymethyl methacrylate n-butyl ester, α -allyloxymethyl methacrylate sec-butyl ester, α -allyloxymethyl acrylate tert-butyl ester, α -allyloxymethyl acrylate n-pentyl ester, α -allyloxymethyl acrylate sec-pentyl ester, α -allyloxymethyl acrylate tert-pentyl ester, and α -allyloxymethyl acrylate neopentyl ester; dialkyl-2, 2' - (oxydimethylene) diacrylate-based monomers such as dimethyl-2, 2' - [ oxybis (methylene) ] bis-2-acrylate, diethyl-2, 2' - [ oxybis (methylene) ] bis-2-acrylate, dicyclohexyl-2, 2' - [ oxybis (methylene) ] bis-2-acrylate, and dibenzyl-2, 2' - [ oxybis (methylene) ] bis-2-acrylate; and so on.

The contents of the monomers (a), (b) and (c) may be appropriately set according to the purpose and use of the desired N-substituted maleimide-based polymer.

The monomer (a) is preferably 0.5% by mass or more, more preferably 1% by mass or more, and still more preferably 3% by mass or more, and preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less, based on 100% by mass of the total monomer components.

The monomer (b) is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass or more, and preferably 60% by mass or less, more preferably 50% by mass or less, and still more preferably 40% by mass or less, based on 100% by mass of the total monomer components.

The monomer (c) is preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably 25% by mass or more, and preferably 90% by mass or less, more preferably 80% by mass or less, and still more preferably 70% by mass or less, based on 100% by mass of the total monomer components.

When 2 or more monomers are contained, the content of each of the monomers (a), (b), and (c) is the total amount thereof.

< Process (I-3) >

The production method (I) further comprises the following step (I-3): an N-substituted maleimide-based polymer having a double bond in a side chain is obtained by reacting the base polymer 1 obtained in the step (I-2) with glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass%.

The chlorine content of the glycidyl (meth) acrylate used in the production method (I) is 0.01 to 0.3 mass%. By using glycidyl (meth) acrylate adjusted to the above range, an N-substituted maleimide-based polymer having a small residual chlorine amount can be produced, and thermal coloration of the polymer can be suppressed. In addition, the polymer can be produced safely.

The chlorine content of the glycidyl (meth) acrylate is preferably 0.25% by mass or less, more preferably 0.20% by mass or less, and even more preferably 0.15% by mass or less, from the viewpoint of further suppressing the thermal coloration of the obtained N-substituted maleimide polymer.

On the other hand, if the glycidyl (meth) acrylate is adjusted so that the chlorine content is less than 0.01 mass%, the production facilities for purification and the like are excessively large, and in addition, the polymerization of glycidyl (meth) acrylate in purification distillation may cause clogging of the apparatus, a decrease in purification yield, and the like, which is not preferable industrially. The lower limit of the chlorine content is preferably 0.03 mass% or more, and more preferably 0.05 mass% or more, from the viewpoint of production cost.

The chlorine content can be determined by measurement by an ICP-MS (inductively coupled plasma mass spectrometry) method, and specifically, can be determined by the method described in the examples below.

As a method for adjusting the chlorine content of the glycidyl (meth) acrylate, for example, a method of purifying glycidyl (meth) acrylate is preferably mentioned.

The method for purifying the glycidyl (meth) acrylate is not particularly limited, and known methods such as distillation, extraction, and column chromatography may be mentioned, and among them, distillation is preferred in that chlorine can be easily and safely removed.

The distillation is not particularly limited, and known distillation methods such as simple distillation, precision distillation (rectification), vacuum distillation (vacuum distillation), molecular distillation, and steam distillation may be mentioned, and among them, precision distillation is preferred, and precision distillation under reduced pressure is more preferred, because high purity can be easily achieved industrially.

The distillation method is not particularly limited, and a known method can be used, and the distillation can be performed by a reduced pressure concentration apparatus such as an evaporator, simple distillation, or precision distillation using a rectifying column.

The distillation temperature is preferably 30 ℃ or higher, more preferably 40 ℃ or higher, and still more preferably 50 ℃ or higher, from the viewpoint of easy condensation and collection in an industrial scale. The distillation temperature is preferably 150 ℃ or lower, more preferably 100 ℃ or lower, and still more preferably 80 ℃ or lower, from the viewpoint of suppressing polymerization during distillation, preventing clogging of the apparatus, and the like.

The distillation is preferably performed under reduced pressure, and for example, preferably 40000Pa or less, preferably 10000Pa or less, and more preferably 3000Pa or less.

Examples of the method for carrying out the distillation under reduced pressure include known methods such as precision distillation including a rectifying column.

The rectifying column used for the distillation preferably has a theoretical plate number of 2 to 100, and more preferably has a theoretical plate number of 5 to 50. When the reduction of the chlorine component by distillation is insufficient, the chlorine component can be reduced to a desired range by repeating distillation a plurality of times. The number of times of repeating the distillation is preferably 3 or less, and more preferably 2 or less. Repeating the distillation 4 times or more is industrially disadvantageous in that the equipment and the steps are excessively large and the distillation yield is lowered.

In the above distillation, a polymerization inhibitor or the like may be added to the glycidyl (meth) acrylate. Polymerization during distillation can be prevented by adding a polymerization inhibitor. Examples of the polymerization inhibitor include commonly used polymerization inhibitors for radical polymerizable monomers, for example, phenol-based polymerization inhibitors such as hydroquinone, methylhydroquinone, trimethylhydroquinone, t-butylhydroquinone, hydroquinone monomethyl ether, 6-t-butyl-2, 4-xylenol, 2, 6-di-t-butylphenol, 2, 6-di-t-butyl-4-methoxyphenol and 2,2' -methylenebis (4-methyl-6-t-butylphenol), copper salts of organic acids, phenothiazine and the like. These may be used alone in 1 kind, or 2 or more kinds may be used in combination. Among them, phenol-based polymerization inhibitors are preferred, and hydroquinone monomethyl ether, 6-tert-butyl-2, 4-xylenol, and 2,2' -methylenebis (4-methyl-6-tert-butylphenol) are more preferred.

Before and/or after the distillation, the glycidyl (meth) acrylate may be washed with a solvent such as water or weakly alkaline water, dried and dehydrated in order to further remove impurities. Particularly, when water is contained in a large amount, the glycidyl group of the glycidyl (meth) acrylate may be hydrolyzed. The content of water is preferably 0.2 parts by mass or less, more preferably 0.1 parts by mass or less, and most preferably 0.05 parts by mass or less, based on 100 parts by mass of glycidyl (meth) acrylate.

As described above, the production method (I) of the present invention preferably comprises the following step (I-1) before the step (I-2) or (I-3): the glycidyl (meth) acrylate is purified so that the chlorine content of the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

The method for reacting the base polymer 1 with the glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass% is not particularly limited, and the glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass% may be mixed with a polymer solution containing the base polymer 1 and reacted by a known method. By the above reaction, the acid group (carboxyl group) of the base polymer 1 reacts with the epoxy group of the glycidyl (meth) acrylate, and the glycidyl (meth) acrylate is added to the base polymer 1 to obtain a polymer having a polymerizable double bond at the terminal.

The temperature of the addition reaction is not particularly limited as long as the addition reaction proceeds, and examples thereof include 60 to 150 ℃, preferably 90 to 140 ℃, and more preferably 100 to 120 ℃.

The reaction time of the addition reaction is not particularly limited, and examples thereof include 1 to 48 hours, preferably 3 to 24 hours, and more preferably 6 to 12 hours.

The amount of the glycidyl (meth) acrylate to be adjusted in the step (I-3) is preferably appropriately set so that the double bond equivalent weight of the obtained N-substituted maleimide-based polymer is within a desired range, and is, for example, preferably 1 to 150 parts by mass, more preferably 10 to 100 parts by mass, and still more preferably 15 to 80 parts by mass, based on 100 parts by mass of the total monomer components to provide the base polymer 1.

In the above addition reaction, there may be used: amine compounds such as trimethylamine, triethylamine, triisopropylamine, tributylamine, dimethylbenzylamine, methyldibenzylamine, and tribenzylamine; phosphines such as triethylphosphine and triphenylphosphine; ammonium salts such as tetraethylammonium chloride; phosphonium salts such as tetraphenylphosphonium bromide and amide compounds such as dimethylformamide; and the like known as catalysts. Among them, amine compounds and phosphines are preferable, and triethylamine, dimethylbenzylamine and triphenylphosphine are more preferable, because coloring is less and industrial availability is easy.

The amount of the catalyst to be used may be appropriately set, and is preferably 0.05 to 5% by mass, more preferably 0.1 to 1% by mass, and still more preferably 0.1 to 0.5% by mass, based on the total amount of the base polymer 1 and the modified glycidyl (meth) acrylate. If the amount of the catalyst used is less than the above range, the reaction time may be prolonged, which may be industrially disadvantageous. If the amount exceeds the above range, the catalyst may form a salt with the base polymer at the time of charging, become insoluble and difficult to stir, or the resulting polymer may have increased thermal coloration.

The production process (I) may have other steps in addition to the steps (I-1), (I-2) and (I-3). Examples of the other steps include an aging step, a neutralization step, a deactivation step of a polymerization initiator or a chain transfer agent, a dilution step, a drying step, a concentration step, a purification step, and the like. These steps can be performed by a known method.

As described above, the production method (I) preferably includes a step of adjusting the chlorine content of the glycidyl (meth) acrylate to be used within a predetermined range.

Therefore, a method for producing an N-substituted maleimide-based polymer, which comprises the steps of: a step (I-1) of purifying glycidyl (meth) acrylate so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%; a step (I-2) for obtaining a base polymer by polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b); and a step (I-3) of reacting the purified glycidyl (meth) acrylate obtained in the step (I-1) with the base polymer to obtain an N-substituted maleimide-based polymer having a double bond in a side chain. The purified glycidyl (meth) acrylate obtained in the step (I-1) is obtained by adjusting the chlorine content to 0.01 to 0.3 mass%.

1-2. Production method (II)

< Process (II-2) >

The production method (II) has the following step (II-2): a base polymer (also referred to as "base polymer 2") is obtained by polymerizing monomer components including an N-substituted maleimide monomer (a) and glycidyl (meth) acrylate whose chlorine content is adjusted to 0.01 to 0.3 mass%.

Examples of the N-substituted maleimide monomer (a) and the glycidyl (meth) acrylate having a chlorine content of 0.01 to 0.3% by mass include those similar to the "N-substituted maleimide monomer (a)" described in the above production process (I) and those having a chlorine content of 0.01 to 0.3% by mass, respectively.

The monomer component for producing the base polymer 2 may further contain a monomer (d) copolymerizable with the monomer (a) and the adjusted glycidyl (meth) acrylate.

Examples of the monomer (d) include the same monomers as those of the monomer (c) described in the above production process (I). These can be used alone in 1, also can be used in 2 or more combinations.

The polymerization method is not particularly limited, and preferred examples thereof include the same polymerization methods as described in the above production method (I).

The contents of the monomer (a), the adjusted glycidyl (meth) acrylate, and the monomer (d) may be appropriately set according to the purpose and use of the desired N-substituted maleimide-based polymer.

The amount of the monomer (a) is preferably 0.5% by mass or more, more preferably 1% by mass or more, and still more preferably 3% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 30% by mass or less, based on 100% by mass of the total monomer components.

The above-mentioned glycidyl (meth) acrylate to be adjusted is preferably 10% by mass or more, more preferably 20% by mass or more, further preferably 30% by mass or more, preferably 90% by mass or less, more preferably 80% by mass or less, further preferably 60% by mass or less, based on 100% by mass of the entire monomer components.

The monomer (d) is preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably 30% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less, and still more preferably 60% by mass or less, based on 100% by mass of the total monomer components.

When 2 or more monomers are contained, the contents of the monomer (a), the adjusted glycidyl (meth) acrylate, and the monomer (d) are the total amount thereof.

The production method (II) of the present invention preferably comprises the following step (II-1) before the step (II-2): the glycidyl (meth) acrylate is purified so that the chlorine content of the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

As the step (II-1), the same steps as in the step (I-1) in the above production process (I) can be preferably used.

< Process (II-3) >

The production method (II) further comprises the following step (II-3): the unsaturated carboxylic acid monomer (b) is reacted with the base polymer 2 obtained in the step (II-2) to obtain an N-substituted maleimide-based polymer having a double bond in a side chain.

The method for reacting the unsaturated carboxylic acid monomer (b) with the base polymer 2 is not particularly limited, and the unsaturated carboxylic acid monomer (b) and, if necessary, a polymerization initiator, a chain transfer agent, and the like may be mixed with a polymer solution containing the base polymer 2 and reacted by a known method.

By the above reaction, the carboxyl group of the unsaturated carboxylic acid monomer (b) reacts with the epoxy group of the base polymer 2, and the unsaturated carboxylic acid monomer (b) is added to obtain an N-substituted maleimide-based polymer having a polymerizable double bond at the terminal.

Examples of the unsaturated carboxylic acid monomer (b) include those similar to the unsaturated carboxylic acid monomer (b) described in the above-mentioned production process (I).

The reaction temperature is not particularly limited as long as the reaction proceeds, and examples thereof include 40 to 200 ℃, preferably 60 to 150 ℃, and more preferably 80 to 120 ℃.

The reaction time is not particularly limited, and may be, for example, 1 to 48 hours, preferably 3 to 24 hours, and more preferably 5 to 12 hours.

The amount of the unsaturated carboxylic acid monomer (b) used in the step (II-3) is preferably set as appropriate so that the double bond equivalent of the obtained N-substituted maleimide-based polymer is within a desired range, and is, for example, preferably 1 to 50 parts by mass, more preferably 5 to 45 parts by mass, and still more preferably 10 to 40 parts by mass, based on 100 parts by mass of the monomer component providing the base polymer 2.

In the above reaction, it is possible to use: amine compounds such as triethylamine and dimethylbenzylamine; ammonium salts such as tetraethylammonium chloride; phosphonium salts such as tetraphenylphosphonium bromide, and amide compounds such as dimethylformamide; and the like known as catalysts. The amount of the above catalyst to be used may be appropriately set.

As described above, the production method (II) preferably includes a step of adjusting the chlorine content of the glycidyl (meth) acrylate to be used to a predetermined range.

Therefore, a method for producing an N-substituted maleimide-based polymer, characterized by comprising the following steps: a step (II-1) of purifying the glycidyl (meth) acrylate so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%; a step (II-2) of polymerizing monomer components including an N-substituted maleimide monomer (a) and the purified glycidyl (meth) acrylate obtained in the step (II-1) to obtain a base polymer; and (II-3) reacting the unsaturated carboxylic acid monomer (b) with the base polymer to obtain an N-substituted maleimide polymer having a double bond in a side chain. The purified glycidyl (meth) acrylate obtained in the step (II-1) is obtained by adjusting the chlorine content to 0.01 to 0.3 mass%.

< Process (II-4) >

In the production method (II), it is preferable that the following step (II-4) is further provided after the step (II-3): reacting a polybasic acid or a polybasic acid anhydride with the N-substituted maleimide-based polymer having a double bond in a side chain. By performing the step (II-4), a polybasic acid or a polybasic acid anhydride is reacted with a hydroxyl group formed by the reaction of an epoxy group with a carboxyl group in the step (II-3), whereby a carboxyl group can be generated, and the acid value of the N-substituted maleimide-based polymer can be adjusted to an appropriate range.

Examples of the polybasic acid or polybasic acid anhydride include: polybasic acids such as succinic acid, maleic acid, phthalic acid, and tetrahydrophthalic acid; dibasic acid anhydrides such as succinic anhydride (also known as succinic anhydride), maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, and itaconic anhydride; trimellitic anhydride; and the like. Among them, succinic acid and polybasic acid anhydrides are preferable, and succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride are preferable in terms of high reactivity and industrial availability.

The reaction temperature in the reaction with the polybasic acid or polybasic acid anhydride is not particularly limited as long as the reaction proceeds, and examples thereof include 0 to 200 ℃, preferably 20 to 150 ℃, and more preferably 30 to 120 ℃.

The reaction time is not particularly limited, and examples thereof include 1 to 12 hours, preferably 2 to 12 hours, and more preferably 2 to 8 hours.

The amount of the polybasic acid or the polybasic acid anhydride to be used is not particularly limited, and may be set so that the acid value of the obtained N-substituted maleimide-based polymer is within a desired range.

The production process (II) may have other steps in addition to the steps (II-1), (II-2), (II-3) and (II-4). Examples of the other steps include an aging step, a neutralization step, a deactivation step of a polymerization initiator or a chain transfer agent, a dilution step, a drying step, a concentration step, a purification step, and the like. These steps can be performed by a known method.

In the N-substituted maleimide-based polymer obtained by the above-mentioned production process (I) or (II), the residual chlorine content in the polymer is preferably 100ppm to 2000ppm based on the total amount of the N-substituted maleimide monomer (a) and glycidyl (meth) acrylate.

The above total amount means the total mass of each monomer used in polymerization.

The residual chlorine content in the polymer is more preferably 1800ppm or less, still more preferably 1500ppm or less, and particularly preferably 1000ppm or less, based on the total amount of the N-substituted maleimide monomer (a) and glycidyl (meth) acrylate, from the viewpoint of further suppressing thermal coloration during curing. The lower limit of the residual chlorine amount is more preferably 200ppm or more, and still more preferably 300ppm or more, based on the total amount of the N-substituted maleimide monomer (a) and the glycidyl (meth) acrylate, from the viewpoint of ease of industrial production of glycidyl (meth) acrylate as a raw material.

The residual chlorine amount in the polymer can be determined as follows: the residual chlorine amount in the polymer was measured by the same method as that for measuring the chlorine content in the glycidyl (meth) acrylate described above, and the obtained value was divided by the total amount (mass) of the N-substituted maleimide monomer (a) and the glycidyl (meth) acrylate used as the raw materials of the polymer.

In the present invention, glycidyl (meth) acrylate whose chlorine content is adjusted to a predetermined range is used, but glycidyl (meth) acrylate which is not adjusted may be used in combination. When not only the above-mentioned modified glycidyl (meth) acrylate but also an unmodified glycidyl (meth) acrylate is used in combination, the amount of the glycidyl (meth) acrylate is the total amount of the glycidyl (meth) acrylate including the unmodified glycidyl (meth) acrylate.

In the N-substituted maleimide-based polymer obtained by the above-mentioned production process (I) or (II), it is preferable that the residual epichlorohydrin content in the polymer is 0.001ppm to 5ppm. When the residual epichlorohydrin amount is within the above range, the N-substituted maleimide-based polymer is excellent in safety during production and use, and can be further inhibited from thermally coloring during curing.

Glycidyl (meth) acrylate is generally produced by the reaction of (meth) acrylic acid with epichlorohydrin. Therefore, chlorine that is not removed remains as an impurity in glycidyl (meth) acrylate, and epichlorohydrin also remains. Epichlorohydrin is known to have very high reactivity and to be a substance harmful to the human body. In the production method of the present invention, residual epichlorohydrin can be reduced in addition to residual chlorine, and an N-substituted maleimide-based polymer which is suppressed in thermal coloration and is excellent in safety can be obtained.

The residual epichlorohydrin amount is more preferably 1ppm or less, and still more preferably 0.5ppm or less. The lower limit of the amount of residual epichlorohydrin is more preferably 0.01ppm or more, from the viewpoint that the equipment required for purification of glycidyl (meth) acrylate is not too large and is industrially advantageous.

The amount of residual epichlorohydrin in the polymer can be determined by measurement by a GC-MS method, and specifically, can be determined by a method described in examples below.

Thus, the N-substituted maleimide-based polymer obtained by the method (I) or (II) for producing an N-substituted maleimide polymer of the present invention has a residual chlorine amount within a predetermined range, and therefore, can remarkably suppress thermal coloration during curing. The N-substituted maleimide-based polymer obtained by the above-mentioned production process (I) or (II) is also one aspect of the present invention.

An example of a preferable embodiment of the N-substituted maleimide polymer obtained in the above-mentioned production process (I) or (II) will be described below.

2.N-substituted maleimide-based polymer

[ solution 3]

(in the general formula (B1), R ¹ And R ³ The same or different, represents a hydrogen atom or a methyl group. R is ² Represents a divalent linking group. a is 0 or 1.

In the general formula (B3), R ⁶ Represents a hydrogen atom or a methyl group. R ⁷ Represents an ethylenically unsaturated bond-containing group. X represents a divalent hydrocarbon group. )

In the N-substituted maleimide-based polymer of the present invention, the amount of residual chlorine in the polymer is 100ppm to 2000ppm based on the total mass of the N-substituted maleimide monomer providing the structural unit (A) and the glycidyl (meth) acrylate providing the structural unit (B) as raw materials for the polymer. Therefore, thermal coloration of the polymer during curing can be suppressed.

The residual chlorine amount is preferably 1800ppm or less, more preferably 1500ppm or less, and still more preferably 1200ppm or less, based on the total mass, from the viewpoint of further suppressing thermal coloration during curing.

The amount of residual chlorine in the polymer can be determined by the same method as the method for determining the amount of residual chlorine in the polymer described in the above "method for producing a 1.N-substituted maleimide-based polymer".

The N-substituted maleimide monomer which provides the structural unit (A) is a polymer raw material for obtaining a polymer having the structural unit (A) by polymerizing a monomer component containing the N-substituted maleimide monomer.

The glycidyl (meth) acrylate that provides the structural unit (B) is not directly provided as the structural unit (B) by polymerization, but can form a polymer raw material of the structural unit (B) by reacting with a functional group derived from another monomer component, or the like. That is, as described later, the structural unit (B) has a structure derived from glycidyl (meth) acrylate.

The N-substituted maleimide-based polymer has a structural unit (A) derived from an N-substituted maleimide monomer and a structural unit (B) represented by the general formula (B1), (B2) or (B3), and the structural unit (B) has a structure derived from glycidyl (meth) acrylate.

The N-substituted maleimide-based polymer having the structural unit derived from the N-substituted maleimide monomer and the structural unit represented by the general formula (B1) can be obtained by the method of the production process (I).

The N-substituted maleimide-based polymer having the structural unit derived from the N-substituted maleimide monomer and the structural unit represented by the general formula (B2) can be obtained by the method of the production process (II), and preferably can be obtained by the methods of the steps (II-1) to (II-3).

The N-substituted maleimide-based polymer having the structural unit derived from the N-substituted maleimide monomer and the structural unit represented by the general formula (B3) can be obtained by the method of the production process (II), and preferably can be obtained by the methods of the steps (II-1) to (II-4).

The N-substituted maleimide-based polymer may have only 1 kind of the structural unit represented by the general formula (B1), the general formula (B2) or the general formula (B3) as the structural unit (B), or may have 2 or more kinds.

The N-substituted maleimide monomer is preferably the same as the N-substituted maleimide monomer (a) described in the above "method for producing a 1.N-substituted maleimide polymer".

In addition, an embodiment having two kinds of structural units, i.e., a structural unit derived from N-benzylmaleimide and a structural unit derived from N-phenylmaleimide, as the structural unit derived from an N-substituted maleimide monomer is also one of preferable embodiments of the present invention.

In the above general formula (B1), R ¹ And R ³ The same or different, represent a hydrogen atom or a methyl group.

R ² Represents a divalent linking group. <xnotran> , , , , , , , -O-, -CO-, - (CO) O-, -NH-, -SO </xnotran> ₂ -and combinations thereof and the like.

The divalent linking group preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 6 carbon atoms.

As R ² Examples of the preferable unsaturated carboxylic acid monomer (b) include residues obtained by removing a polymerizable double bond group and a carboxyl group or a carboxylic acid anhydride group from the unsaturated carboxylic acid monomer (b) described in the above "method for producing a 1.N-substituted maleimide-based polymer", and specific examples thereof include- (CO) O-CH = CH-.

Examples of the polymerizable double bond group include a vinyl group, a (meth) acryloyl group, an allyl group, and a methallyl group.

a is 0 or 1, and is preferably 0 from the viewpoint of reactivity and industrial availability.

In the above general formula (B2), R ⁴ Represents a hydrogen atom or a methyl group.

R ⁵ Represents an ethylenically unsaturated bond-containing group. Examples of the ethylenically unsaturated bond-containing group include groups containing a polymerizable double bond such as a (meth) acryloyl group, a vinyl group, an allyl group, and a methallyl group, and preferable examples thereof include a residue obtained by removing a carboxyl group or a carboxylic anhydride group from the unsaturated carboxylic acid monomer (b) described in the above "method for producing a 1.N-substituted maleimide-based polymer".

As R ⁵ Specific examples thereof include- (CH) ₂ ) _m -O(CO)-CH＝CH ₂ (m is an integer of 1 to 6), -CH = CH ₂ 、-C(CH ₃ )＝CH ₂ Etc., wherein-CH = CH is preferable ₂ 、-C(CH ₃ )＝CH ₂ 。

In the above general formula (B3), R ⁶ Represents a hydrogen atom or a methyl group.

R ⁷ Represents an ethylenically unsaturated bond-containing group. The ethylenically unsaturated bond-containing group preferably includes the group represented by the formula R ⁵ The ethylenically unsaturated bond-containing group of (a) is the same as that of (b).

X represents a divalent hydrocarbon group. Examples of the divalent hydrocarbon group include a divalent chain or cyclic aliphatic hydrocarbon group and a divalent aromatic hydrocarbon group.

Examples of the divalent chain aliphatic hydrocarbon group include methylene, ethylene, trimethylene, propylene, ethylidene, propylidene, isopropylidene, vinylene, propenylene, and ethenylidene groups, and examples thereof include a divalent chain aliphatic hydrocarbon group having preferably 1 to 12 carbon atoms, and more preferably 1 to 6 carbon atoms.

Examples of the divalent cyclic aliphatic hydrocarbon group include 1, 2-cyclopentylene, 1, 2-cyclohexylene, 1, 4-cyclohexylene, 1, 2-cyclohexenylene, 1, 4-cyclohexenylene, cyclopentylidene, cyclohexylidene and the like, and divalent cyclic aliphatic hydrocarbon groups having preferably 4 to 12 carbon atoms, more preferably 4 to 8 carbon atoms are exemplified.

Examples of the divalent aromatic hydrocarbon group include, for example, a1, 2-phenylene group, a1, 2-naphthylene group, a 2, 3-naphthylene group, a benzylidene group, a cinnamylidene group and the like, and examples thereof include a divalent aromatic hydrocarbon group having preferably 6 to 18 carbon atoms, more preferably 6 to 12 carbon atoms.

Among these, X is preferably a residue obtained by removing a carboxyl group or a carboxylic anhydride group from a polybasic acid or a polybasic acid anhydride described in the above "method for producing a 1.N-substituted maleimide-based polymer". Specific examples of X include- (CH) ₂ ) ₂ -、-CH＝CH-、-CH ₂ -C(＝CH ₂ ) H-, phenylene, cyclohexylene, cyclohexenylene, and the like.

In the general formulae (B1), (B2) and (B3), the structures derived from glycidyl groups in the (meth) acrylic acid chains are as follows.

[ solution 4]

The N-substituted maleimide-based polymer may have a structural unit (C) other than the structural units (A) and (B). Examples of the other structural unit (C) include structural units derived from the monomer (C) described in the above "method for producing a 1.N-substituted maleimide-based polymer".

The N-substituted maleimide-based polymer may have a structural unit not derived from glycidyl (meth) acrylate and represented by the general formula (B1), (B2) or (B3). This structural unit is contained in the other structural unit (C).

The content ratio of each of the structural units (A), (B) and (C) can be appropriately set according to the purpose and use of the N-substituted maleimide-based polymer. For example, the content of the structural unit (a) is preferably 0.5 to 50% by mass, more preferably 1 to 30% by mass, and still more preferably 3 to 20% by mass, based on 100% by mass of the total structural units.

The content ratio of the structural unit (B) is preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and still more preferably 20 to 40% by mass.

The content ratio of the structural unit (C) is preferably 10 to 90% by mass, more preferably 20 to 80% by mass, and still more preferably 25 to 70% by mass.

The weight average molecular weight of the N-substituted maleimide-based polymer may be appropriately set according to the purpose and use of the polymer, and is preferably 2000 to 1000000, more preferably 3000 or more, and still more preferably 5000 or more. Further, 50000 or less is more preferable, and 30000 or less is even more preferable.

The weight average molecular weight can be determined by a Gel Permeation Chromatography (GPC) method, and specifically, can be determined by the method described in examples below.

The acid value of the N-substituted maleimide polymer is preferably from 20mgKOH/g to 200mgKOH/g, more preferably 30mgKOH/g or more, still more preferably 40mgKOH/g or more, still more preferably 180mgKOH/g or less, and yet more preferably 160mgKOH/g or less.

The acid value can be determined by a neutralization titration method using a KOH solution.

The N-substituted maleimide-based polymer has a double bond in a side chain. The double bond equivalent of the N-substituted maleimide-based polymer is preferably 300 g/equivalent to 30000 g/equivalent. The double bond equivalent is more preferably 400 g/equivalent or more, and still more preferably 420 g/equivalent or more from the viewpoint of excellent storage stability of the polymer, and is more preferably 3000 g/equivalent or less, and still more preferably 2000 g/equivalent or less from the viewpoint of reactivity with light or heat.

The equivalent weight of the double bond means the mass of the solid content of the polymer solution per 1mol of the double bond of the N-substituted maleimide-based polymer. The double bond equivalent weight can be determined by dividing the mass (g) of the resin solid content of the polymer solution by the amount (mol) of double bonds in the polymer. Further, the measurement may be carried out by titration, elemental analysis, various analyses such as NMR and IR, or differential scanning calorimetry. For example, the following can be used in accordance with JIS K0070: 1992, by measuring the number of ethylenic double bonds contained per 1g of polymer.

3. Curable resin composition

The above-mentioned N-substituted maleimide-based polymer can be further combined with a polymerizable compound to prepare a curable resin composition. The curable resin composition contains the N-substituted maleimide polymer, and therefore can provide a cured product in which heat-induced coloration is suppressed. Further, by further including a polymerizable compound, various physical properties such as curability of the resin composition, mechanical strength of a cured product, and solvent resistance can be improved. The curable resin composition comprising the N-substituted maleimide-based polymer and the polymerizable compound is also one aspect of the present invention. The curable resin composition of the present invention can also be suitably used as a photosensitive resin composition.

The content of the N-substituted maleimide-based polymer in the curable resin composition of the present invention is not particularly limited, and may be appropriately set according to the application, blending of other components, and the like, and is, for example, preferably 5 to 90 mass%, more preferably 10 to 80 mass%, and still more preferably 15 to 70 mass% with respect to 100 mass% of the total solid content of the curable resin composition.

The "total solid content" refers to the total amount of components forming a cured product (components excluding a solvent and the like that volatilize at the time of formation of the cured product).

< polymerizable Compound >

Examples of the polymerizable compound include low-molecular compounds having a polymerizable unsaturated bond (also referred to as a polymerizable unsaturated group) which can be polymerized by irradiation with active energy rays such as a radical, an electromagnetic wave (e.g., infrared ray, ultraviolet ray, X-ray, etc.), an electron beam, etc., and examples thereof include monofunctional compounds having 1 polymerizable unsaturated group or polyfunctional compounds having 2 or more polymerizable unsaturated groups in the molecule.

Examples of the monofunctional compound include N-substituted maleimide monomers; (meth) acrylates; (meth) acrylamides; unsaturated monocarboxylic acids; unsaturated polycarboxylic acids; unsaturated monocarboxylic acids chain-extended between the unsaturated group and the carboxyl group; unsaturated acid anhydrides; aromatic vinyls; conjugated dienes; vinyl esters; vinyl ethers; n-vinyl compounds; unsaturated isocyanates; and the like. Examples of these compounds include the same compounds as those listed as monomer components of the N-substituted maleimide-based polymer. In addition, a monomer having an active methylene group or an active methine group may be used.

Examples of the polyfunctional compound include the following compounds.

2-functional (meth) acrylate compounds such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, bisphenol a alkylene oxide di (meth) acrylate, and bisphenol F alkylene oxide di (meth) acrylate;

trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, glycerol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol hepta (meth) acrylate, tripentaerythritol octa (meth) acrylate, ethylene oxide-added trimethylolpropane tri (meth) acrylate, ethylene oxide-added ditrimethylolpropane tetra (meth) acrylate, ethylene oxide-added pentaerythritol tetra (meth) acrylate, ethylene oxide-added dipentaerythritol hexa (meth) acrylate, propylene oxide-added trimethylolpropane tri (meth) acrylate, propylene oxide-added ditrimethylolpropane tetra (meth) acrylate, propylene oxide-added pentaerythritol tetra (meth) acrylate, propylene oxide-added dipentaerythritol hexa (meth) acrylate, epsilon-caprolactone-added trimethylolpropane tri (meth) acrylate, epsilon-caprolactone-added ditrimethylolpropane tetra (meth) acrylate, epsilon-caprolactone-added pentaerythritol tetra (meth) acrylate, pentaerythritol-added epsilon-caprolactone-added succinate modified pentaerythritol succinate, pentaerythritol tri (meth) acrylate, and modified pentaerythritol triacrylate, A dipentaerythritol pentaacrylate phthalate modified product, a pentaerythritol triacrylate phthalate modified product, and the following formula:

[ solution 5]

A polyfunctional (meth) acrylate compound having 3 or more functions such as a modified product of dipentaerythritol hexaacrylate represented by the above;

polyfunctional vinyl ethers such as ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, hexanediol divinyl ether, bisphenol a alkylene oxide divinyl ether, bisphenol F alkylene oxide divinyl ether, trimethylolpropane trivinyl ether, ditrimethylolpropane tetravinyl ether, glycerol trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, ethylene oxide-trimethylolpropane trivinyl ether, ethylene oxide-ditrimethylolpropane tetravinyl ether, ethylene oxide-pentaerythritol tetravinyl ether, and ethylene oxide-dipentaerythritol hexavinyl ether;

vinyl ether group-containing (meth) acrylic acid esters such as 2-vinyloxyethyl (meth) acrylate, 3-vinyloxypropyl (meth) acrylate, 1-methyl-2-vinyloxyethyl (meth) acrylate, 2-vinyloxypropyl (meth) acrylate, 4-vinyloxybutyl (meth) acrylate, 4-vinyloxycyclohexyl (meth) acrylate, 5-vinyloxypentyl (meth) acrylate, 6-vinyloxyhexyl (meth) acrylate, 4-vinyloxymethylcyclohexyl methyl (meth) acrylate, p-vinyloxymethylphenyl methyl (meth) acrylate, 2- (vinyloxyethoxy) ethyl (meth) acrylate, and 2- (vinyloxyethoxyethoxyethoxy) ethyl (meth) acrylate;

polyfunctional allyl ethers such as ethylene glycol diallyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether, propylene glycol diallyl ether, butylene glycol diallyl ether, hexanediol diallyl ether, bisphenol a alkylene oxide diallyl ether, bisphenol F alkylene oxide diallyl ether, trimethylolpropane triallyl ether, ditrimethylolpropane tetraallyl ether, glycerol triallyl ether, pentaerythritol tetraallyl ether, dipentaerythritol pentaallyl ether, dipentaerythritol hexaallyl ether, ethylene oxide-added trimethylolpropane triallyl ether, ethylene oxide-added ditrimethylolpropane tetraallyl ether, ethylene oxide-added pentaerythritol tetraallyl ether, and ethylene oxide-added dipentaerythritol hexaallyl ether;

allyl group-containing (meth) acrylates such as allyl (meth) acrylate; polyfunctional (meth) acryloyl group-containing isocyanurates such as tris (acryloyloxyethyl) isocyanurate, tris (methacryloyloxyethyl) isocyanurate, alkylene oxide-added tris (acryloyloxyethyl) isocyanurate, and alkylene oxide-added tris (methacryloyloxyethyl) isocyanurate; polyfunctional allyl-containing isocyanurates such as triallylisocyanurate; polyfunctional urethane (meth) acrylates obtained by the reaction of polyfunctional isocyanates such as tolylene diisocyanate, isophorone diisocyanate, and xylylene diisocyanate with hydroxyl group-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; polyfunctional aromatic vinyl compounds such as divinylbenzene; and so on.

Among the polymerizable compounds, a polyfunctional polymerizable compound is preferably used in order to further improve the curability of the curable resin composition. The number of functional groups of the polyfunctional polymerizable compound is preferably 3 or more, and more preferably 4 or more. The number of functional groups is preferably 10 or less, more preferably 8 or less.

The molecular weight of the polymerizable compound is not particularly limited, and is preferably 2000 or less, for example, from the viewpoint of handling.

Among the above polyfunctional polymerizable compounds, compounds having a (meth) acryloyl group such as polyfunctional (meth) acrylate compounds, polyfunctional urethane (meth) acrylate compounds, and (meth) acryloyl group-containing isocyanurate compounds are preferred, and polyfunctional (meth) acrylate compounds are more preferred, from the viewpoints of reactivity, economy, availability, and the like. By containing the compound having a (meth) acryloyl group, the curable resin composition is more excellent in photosensitivity and curability, and a cured product having high transparency can be obtained with higher hardness. As the above-mentioned polyfunctional polymerizable compound, a polyfunctional (meth) acrylate compound having 3 or more functions is more preferably used.

The polymerizable compound may be used alone in 1 kind, or may be used in combination with 2 or more kinds.

The content of the polymerizable compound in the curable resin composition of the present invention is not particularly limited, and may be appropriately set, and for example, is preferably 5% by mass to 95% by mass, more preferably 10% by mass or more, further preferably 15% by mass or more, and further preferably 85% by mass or less, further preferably 80% by mass or less, relative to 100% by mass of the total solid content of the curable resin composition of the present invention.

< photopolymerization initiator >

The curable resin composition of the present invention may further contain a photopolymerization initiator. By containing a photopolymerization initiator, the curability of the curable resin composition can be improved, and the performance of the obtained cured product can be improved.

The photopolymerization initiator used in the present invention is preferably a radical polymerizable photopolymerization initiator. The radical polymerizable photopolymerization initiator is a substance that generates a polymerization initiating radical upon irradiation with active energy rays such as electromagnetic waves or electron beams.

The photopolymerization initiator is not particularly limited, and known photopolymerization initiators such as alkylbenzene ketone compounds, benzophenone compounds, benzoin compounds, thioxanthone compounds, halomethylated triazine compounds, halomethylated oxadiazole compounds, biimidazole compounds, oxime ester compounds, oxime ether compounds, cyclopentadienyl titanium compounds, benzoate compounds, and acridine compounds can be used.

Among them, the photopolymerization initiator is preferably an alkyl-benzophenone compound, an oxime-ester compound or an oxime-ether compound, and more preferably an alkyl-benzophenone compound such as 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-1-propanone ("IRGACURE 907", manufactured by BASF), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone ("IRGACURE 369", manufactured by BASF), 1- [4- (phenylthio) phenyl ] -1, 2-octanedione 2- (O-benzoyloxime) ("OXE 01", manufactured by BASF), 1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone 1- (O-acetyloxime) ("OXE 02", manufactured by BASF), 1- [4- (phenylthio) ] -1, 2-octanedione 2- (O-benzoyloxime) ("OXE", manufactured by BASF 03", manufactured by BASF), 1- [ 9-ethyl-6- (2-methylcarbazol-3-yl) ] ethanone, or the like, and the oxime-1- [4- (O-acetyl) -2-benzoyl-oxime-3-yl ] ethanone 04", manufactured by BASF).

The photopolymerization initiator may be used alone in 1 kind, or may be used in combination with 2 or more kinds.

The content of the photopolymerization initiator in the curable resin composition of the present invention is not particularly limited as long as the effect of the present invention is exerted, and may be appropriately set, for example, preferably 0.1 to 30% by mass, more preferably 0.5 to 25% by mass, and further preferably 1 to 20% by mass, based on 100% by mass of the total solid content of the curable resin composition of the present invention.

Further, 1 or 2 or more kinds of photosensitizers, photoradical polymerization promoters, and the like may be used in combination as required. By using a photosensitizer and/or a photo radical polymerization accelerator together with the photopolymerization initiator, the sensitivity and curability are further improved.

Examples of the photosensitizer and the photoradical polymerization accelerator include: pigment-based compounds such as xanthene dye, coumarin dye, 3-coumarin ketone-based compounds, and pyrromethene dye; dialkylaminobenzene compounds such as ethyl 4-dimethylaminobenzoate and 2-ethylhexyl 4-dimethylaminobenzoate; and thiol-based hydrogen donors such as 2-mercaptobenzothiazole, 2-mercaptobenzoxazole and 2-mercaptobenzimidazole. The amount of the surfactant to be used may be appropriately determined by a known method.

< other ingredients >

The curable resin composition of the present invention may further contain other components as necessary. Examples of the other components include: a solvent; a colorant; a dispersant; an antioxidant; a heat resistance improver; leveling agent; a developing aid; quantum dot particles; inorganic fine particles such as zirconia or silica fine particles; silane-based, aluminum-based, titanium-based coupling agents; thermosetting resins such as fillers, epoxy resins, phenol resins, polyvinyl phenols, and the like; curing aids such as polyfunctional thiol compounds; a plasticizer; a polymerization inhibitor; an ultraviolet absorber; a matting agent; defoaming agent; an antistatic agent; a slip agent; a surface modifier; a thixotropic agent; a thixotropic auxiliary agent; a quinone diazide compound; a polyhydric phenol compound; an acid generator; and so on. These can be used alone, or in combination of 2 or more. These components may be appropriately selected from known substances and used in an appropriate amount.

< method for producing curable resin composition >

The method for producing the curable resin composition of the present invention is not particularly limited, and a known method may be used, and examples thereof include a method of mixing and dispersing the above-mentioned components using various mixers and dispersers. The mixing and dispersing method is not particularly limited, and may be performed by a known method. In addition, other processes that are generally performed may be further included. When the curable resin composition contains a coloring material, a dispersion solution of the coloring material may be prepared in advance, and then the dispersion solution may be mixed with the components. The dispersion solution of the coloring material can be obtained by mixing the coloring material, the dispersant and the solvent and performing dispersion treatment using a known dispersion machine such as a bead mill, a roll mill, a ball mill, a jet mill, a homogenizer, a kneader or a stirrer. The obtained curable resin composition may be subjected to a filtration treatment using a filter or the like as necessary to remove fine impurities in the composition.

The curable resin composition of the present invention can be applied to a substrate or formed into an arbitrary shape, for example, depending on the composition, purpose, and use of the curable resin composition, and the coated article or formed article is heated and/or irradiated with an active energy ray to be cured to obtain a cured product.

The coating and molding methods can be performed by known methods.

The heating and the irradiation with active energy rays may be appropriately selected from known methods according to the composition of the curable resin composition and the like.

Examples of the active energy ray include ultraviolet rays and electron beams, and among them, ultraviolet rays are preferable.

The heating method is not particularly limited, and examples thereof include a method of heating at 180 to 280 ℃ for 5 to 120 minutes, preferably at 210 to 250 ℃ for 10 to 60 minutes.

4. Use of

The N-substituted maleimide-based polymer and the curable resin composition containing the N-substituted maleimide-based polymer according to the present invention can provide a cured product in which thermal coloration is suppressed. Therefore, the N-substituted maleimide-based polymer and the curable resin composition of the present invention can be suitably used for applications in which suppression of thermal coloration is desired.

Specific examples of the above-mentioned applications include optical components and electric/electronic components such as color filters, black matrices, optical spacers, black columnar spacers, inks, printing plates, printed wiring boards, semiconductor elements, photoresists, and insulating films used in liquid crystal/organic EL/quantum dot/micro LED liquid crystal display devices, solid-state image pickup elements, touch panel display devices, and the like; automotive parts; coating materials, and the like.

Examples

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "part" means "part by mass" and "%" means "% by mass". The measurement methods for various physical properties are as follows.

< residual chlorine amount >

The obtained N-substituted maleimide polymer solution was diluted 100 times with THF to prepare a sample for measurement, and the amount of residual chlorine in the N-substituted maleimide polymer was determined by measurement under the following conditions.

The device comprises the following steps: ICP-MS Agilent 7700x, manufactured by Agilent Technologies Inc

Mass scan speed: 5000amu/s

The residual chlorine amount relative to the total amount of the N-substituted maleimide and the glycidyl methacrylate is determined by dividing the value of the residual chlorine amount obtained by the above measurement by the value of the ratio of the total mass of the N-substituted maleimide and the glycidyl methacrylate used in the synthesis to the total mass of the N-substituted maleimide-based polymer solution.

< weight average molecular weight >

The weight average molecular weight of the N-substituted maleimide-based polymer was determined by Gel Permeation Chromatography (GPC) under the following conditions.

The device comprises the following steps: HLC-8320GPC manufactured by Tosoh

A detector: RI (Ri)

Column: TSKgel SuperHZM-M

Column temperature: 30 deg.C

Flow rate: 0.6ml/min

And (3) correcting a curve: polystyrene standard product

Eluent: THF (tetrahydrofuran)

< Polymer concentration (% by mass) >

About 1g of the polymer solution was put into an aluminum cup, and about 3g of acetone was added thereto to dissolve the polymer solution, followed by natural drying at room temperature. Then, the sheet was dried at 160 ℃ for 1.5 hours under vacuum using a hot air dryer (PHH-101, product name, manufactured by Espec corporation), and then cooled naturally in the dryer, and the mass was measured. The solid content (% by mass) of the polymer solution was calculated from the mass reduction amount.

< acid value >

1.5g of the polymer solution was accurately weighed, dissolved in a mixed solvent of 90g of acetone and 10g of water, and titrated with a 0.1N KOH aqueous solution. The titration was carried out using an automatic titrator (trade name: COM-555, manufactured by Ponga industries, ltd.) to determine the acid value (mgKOH/g) per 1g of the polymer from the polymer concentration.

< double bond equivalent >

According to JIS K0070: 1992, the number of ethylenic double bonds contained per 1g of polymer was determined and calculated therefrom.

< residual epichlorohydrin amount >

The amount of epichlorohydrin contained in the N-substituted maleimide-based polymer solution was determined by GC-MS measurement under the following conditions.

The device comprises the following steps: GC-MS: polarisQ manufactured by ThermoQuest corporation

The mass range is as follows: m/e 20-200EI process

A thermostatic bath: 40 deg.C (0 min) → 10 deg.C/min → 200 deg.C (0 min)

Flow rate: he 1.0ml/min

Sample adjustment: the polymer solution was diluted 5-fold with methanol

< Heat resistance >

(preparation of resin composition solution)

A resin composition solution was obtained by mixing 10 parts of an N-substituted maleimide polymer solution, 10 parts of dipentaerythritol hexaacrylate (DPHA) as a radical polymerizable compound, 1 part of Irgacure907 (manufactured by BASF) as a photopolymerization initiator, and 30 parts of PGMEA.

(b ^* Measurement of value)

The obtained resin composition solution was uniformly applied to a 5 cm-square glass substrate (soda lime glass AS-2K, manufactured by Toxinseh corporation) by using a spin coater (1H-D7, manufactured by MIKASA K.K.) so that the amount of the applied resin composition solution was 0.4 to 1.2mg/cm in terms of solid content ² . At this time, 2 coated plates having different coating amounts were produced by changing the rotation speed of the spin coater for each resin composition and changing the coating amount (in terms of solid content). The coating amount of 1 of the 2 sheets is more than 0.6mg/cm ² The coating weight of the other 1 piece is always less than 0.6mg/cm ² The value of (c).

These coated sheets were dried at 90 ℃ for 3 minutes to obtain a laminate having a coating film formed on a glass substrate. Then, at 100mJ/cm ² After the resin adhered to the end of the glass substrate was removed by ultraviolet exposure, the resulting laminate was heated at 230 ℃ for 30 minutes using a Perfect oven (manufactured by Espec corporation), and cooled to room temperature. After cooling downThe surface of the coating film of the laminate was measured with a colorimeter ZE6000 (manufactured by Nippon Denshoku industries Co., ltd.) to obtain b after the heat test ^* The value is obtained. For each coating film, the coating amounts (x) and b were determined from the measured values of 2 coating films prepared as described above ^* Approximate straight line (calibration curve) of the value (y) with a coating weight of 0.6mg/cm ² B of (1) ^* The values were obtained as the results of evaluating the heat resistance of each coating film.

Purification of glycidyl methacrylate

Preparation example 1

Commercially available glycidyl methacrylate (manufactured by nippon oil & fat company) was washed with water using a decanter, and then the oil was separated using a separatory funnel and dried and dehydrated using silica gel until the water content became 500ppm or less. Then, precision distillation was carried out at 64 to 66 ℃ under a reduced pressure of 800Pa using a glass vacuum distillation apparatus having a rectifying column with 10 stages of theoretical plate number having a packing, and 200ppm of hydroquinone monomethyl ether was added as a polymerization inhibitor to obtain purified glycidyl methacrylate A.

The chlorine content of the obtained purified glycidyl methacrylate a (purified product a) was measured, and found to be 0.2 mass%.

The chlorine content of glycidyl methacrylate (commercially available product) before purification was measured and found to be 0.5 mass%.

The chlorine content in glycidyl methacrylate was measured by the same method as the residual chlorine content in the above N-substituted maleimide-based polymer.

(preparation example 2)

The purified glycidyl methacrylate a obtained in production example 1 was again washed with water using a decanter, and then the oil was separated using a separatory funnel, dehydrated and dried using silica gel, and then precision distilled by the same method as in production example 1, and 200ppm of hydroquinone monomethyl ether was added to obtain purified glycidyl methacrylate B.

The chlorine content of the obtained purified glycidyl methacrylate B (purified product B) was measured, and found to be 0.1 mass%.

(example 1)

347.9g of Propylene Glycol Monomethyl Ether Acetate (PGMEA) and 156.8g of Propylene Glycol (PGM) were charged into a 2L separable flask, and the temperature was raised to 90 ℃ under nitrogen substitution.

On the other hand, 67.0g of N-benzylmaleimide (BzMI), 163.48g of cyclohexyl methacrylate (CHMA), 3.35g of Methyl Methacrylate (MMA), 101.17g of methacrylic acid (MAA), 70.3g of PGMEA70, 20.2g of PGM, 6.7g of a polymerization initiator (Perbutyl (registered trademark) O, manufactured by Nichikura corporation) and 6.7g of a chain transfer agent (N-dodecylmercaptan) were put into a dropping tank, mixed and stirred, and BzMI was dissolved.

After dropping continuously from the dropping tank at 90 ℃ for 3 hours, the reaction tank was further kept at 90 ℃ for 30 minutes. Then, the temperature was raised to 115 ℃ to carry out the reaction for 1.5 hours. After the reaction, the reaction mixture was cooled to room temperature to obtain a base polymer solution.

To the obtained base polymer solution were added 55.32g of the purified glycidyl methacrylate A (purified product A) obtained in production example 1, 1.2g of triethylamine and 0.6g of a polymerization inhibitor (ANTAGE (registered trademark) W400, manufactured by Kayokoku K.K.), and the mixture was bubbled with an oxygen/nitrogen mixed gas adjusted to an oxygen concentration of 7% at 20ml/min, and the temperature was raised to 115 ℃ to carry out a reaction for 8 hours. Then, the mixture was cooled to room temperature to obtain N-substituted maleimide polymer solution 1 (1000.72 g).

The total amount of BzMI and Glycidyl Methacrylate (GMA) used was 122.32g relative to the total amount of the polymer solution 1, and thus the ratio of the total amount of BzMI and glycidyl methacrylate used relative to the total amount of the liquid was 12.22%.

The obtained N-substituted maleimide-based polymer solution 1 was measured for the weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the polymer by the methods described above. The residual chlorine amount was 100ppm relative to the polymer solution. Thus, the residual chlorine amount to the total amount of BzMI and GMA was calculated to be 100/12.22% =820ppm. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 2)

An N-substituted maleimide-based polymer solution 2 was obtained in the same manner as in example 1, except that N-cyclohexylmaleimide was used instead of N-benzylmaleimide in example 1.

The weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the polymer of the obtained N-substituted maleimide-based polymer solution 2 were measured by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 3)

A resin solution 3 containing an N-substituted maleimide was obtained in the same manner as in example 1, except that the purified glycidyl methacrylate B (purified product B) obtained in production example 2 was used in place of the purified glycidyl methacrylate a (purified product a) in example 1.

The obtained N-substituted maleimide-based polymer solution 3 was measured for the weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the polymer by the above-described method. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 4)

312.8g of Propylene Glycol Monomethyl Ether Acetate (PGMEA) and 83.2g of Propylene Glycol (PGM) were put into a 2L separable flask, and then the temperature was raised to 90 ℃ by replacing nitrogen gas.

On the other hand, 36.0g of N-benzylmaleimide (BzMI), 95.04g of benzyl methacrylate (BzMA), 108.96g of Acrylic Acid (AA), 115.2g of PGMEA28.8g of PGM28, 4.8g of a polymerization initiator (Perbutyl (registered trademark) O, manufactured by Nikko oil) and 0.72g of a chain transfer agent (N-dodecylmercaptan) were put into a dropping tank, mixed and stirred to dissolve BzMI.

After dropping continuously from the dropping tank at 90 ℃ for 3 hours, the reaction tank was further kept at 90 ℃ for 30 minutes. Then, the temperature was raised to 115 ℃ to carry out the reaction for 1.5 hours.

After cooling to room temperature once, 165.2g of purified glycidyl methacrylate B (purified product B) obtained in production example 2, 1.2g of dimethylbenzylamine and 0.6g of a polymerization inhibitor (ANTAGE (registered trademark) W400, manufactured by Kayokoku chemical Co., ltd.) were added thereto, and the reaction was carried out for 12 hours while raising the temperature to 110 ℃ by bubbling with an oxygen/nitrogen mixed gas having an oxygen concentration of 7% adjusted to 20 ml/min.

Then, the mixture was cooled to room temperature to obtain an N-substituted maleimide polymer solution 4.

The weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the obtained N-substituted maleimide-based polymer solution 4 were measured by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 5)

522.0g of Propylene Glycol Monomethyl Ether Acetate (PGMEA) was put into a 2L separable flask, and the temperature was raised to 90 ℃ by replacing nitrogen gas.

On the other hand, 43.6g of N-benzylmaleimide (BzMI), 66.9g of benzyl methacrylate (BzMA), 123.8g of purified glycidyl methacrylate (purified product B) obtained in production example 2, 100.0g of PGMEA, 4.8g of a polymerization initiator (t-butyl peroxy (2-ethylhexanoate)) and 2.72g of a chain transfer agent (N-dodecylmercaptan) were put into a dropping tank, and mixed and stirred to dissolve BzMI.

After cooling to room temperature once, 62.8g of Acrylic Acid (AA), 1.2g of dimethylbenzylamine, and 0.6g of a polymerization inhibitor (ANTAGE (registered trademark) W400, manufactured by Kaikou chemical Co., ltd.) were added thereto, and the mixture was heated to 110 ℃ while bubbling with an oxygen/nitrogen mixed gas having an oxygen concentration of 7% adjusted to 20ml/min, thereby carrying out a reaction for 12 hours.

Then, the mixture was cooled to room temperature, 81.7g of tetrahydrophthalic anhydride (THPA) was added thereto, and the mixture was reacted at 100 ℃ for 3 hours, followed by cooling to room temperature to obtain an N-substituted maleimide polymer solution 5.

The obtained N-substituted maleimide-based polymer solution 5 was measured for the weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the polymer by the above-described method. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 6)

The same procedures as in example 1 were repeated except for changing the amount of N-benzylmaleimide (BzMI) to 6.7g and the amount of cyclohexyl methacrylate (CHMA) to 223.78g, to obtain an N-substituted maleimide-based polymer solution 6.

The weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the obtained N-substituted maleimide-based polymer solution 6 were measured by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

(example 7)

An N-substituted maleimide polymer solution 7 was obtained in the same manner as in example 3, except that 6.7g of N-benzylmaleimide (BzMI) and 60.3g of Phenylmaleimide (PMI) were changed.

The obtained N-substituted maleimide-based polymer solution 7 was measured for the weight average molecular weight, polymer concentration, acid value, double bond equivalent, residual chlorine amount, and epichlorohydrin amount of the polymer by the above-described method. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

Comparative example 1

An N-substituted maleimide-based polymer solution 8 was obtained in the same manner as in example 1, except that instead of purifying glycidyl methacrylate A, non-purified glycidyl methacrylate (commercially available product) was used in example 1.

The weight average molecular weight, acid value, double bond equivalent, polymer concentration, residual chlorine amount, and epichlorohydrin amount of the polymer of the obtained N-substituted maleimide-based polymer solution 8 were measured by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

Comparative example 2

An N-substituted maleimide polymer solution 9 was obtained in the same manner as in example 4, except that in example 4, instead of purifying glycidyl methacrylate B, unpurified glycidyl methacrylate (commercially available product) was used.

The weight average molecular weight, acid value, double bond equivalent, polymer concentration, residual chlorine amount, and epichlorohydrin amount of the obtained N-substituted maleimide-based polymer solution 9 were measured by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

Comparative example 3

An N-substituted maleimide-based polymer solution 10 was obtained in the same manner as in example 7, except that in example 7, instead of purifying glycidyl methacrylate B, unpurified glycidyl methacrylate (commercially available product) was used.

The obtained N-substituted maleimide-based polymer solution 10 was measured for the weight average molecular weight, acid value, double bond equivalent, polymer concentration, residual chlorine amount, and epichlorohydrin amount by the methods described above. In addition, the heat resistance was evaluated by the above-mentioned method. The results are shown in Table 1.

The descriptions in table 1 indicate the following meanings.

BzMI: n-benzylmaleimides

CHMI: n-cyclohexyl maleimide

PMI: phenylmaleimides

CHMA: cyclohexyl methacrylate

MMA: methacrylic acid methyl ester

BzMA: methacrylic acid benzyl ester

MAA: methacrylic acid

AA: acrylic acid

GMA: glycidyl methacrylate

THPA: tetrahydrophthalic anhydride

And (3) a purified product A: purification of glycidyl methacrylate A

And (3) a purified product B: purification of glycidyl methacrylate B

Commercial products: glycidyl methacrylate without purification

As is clear from table 1, the N-substituted maleimide-based polymer obtained using the glycidyl (meth) acrylate adjusted so that the chlorine content is 0.01 to 0.3 mass% is superior in heat resistance and remarkably suppressed in thermal coloration during curing, compared with the N-substituted maleimide-based polymer obtained using the glycidyl (meth) acrylate having a chlorine content exceeding 0.3 mass%.

Claims

1. A method for producing an N-substituted maleimide polymer, characterized by comprising the steps of:

a step (I-2) for polymerizing monomer components including an N-substituted maleimide monomer (a) and an unsaturated carboxylic acid monomer (b) to obtain a base polymer; and

and (I-3) reacting the base polymer with glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass% to obtain an N-substituted maleimide polymer having a double bond in a side chain.

2. The process for producing an N-substituted maleimide-based polymer according to claim 1, further comprising the following step (I-1) before the step (I-2): the glycidyl (meth) acrylate is purified so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

3. A method for producing an N-substituted maleimide polymer, characterized by comprising the steps of:

a step (II-2) for obtaining a base polymer by polymerizing monomer components comprising an N-substituted maleimide monomer (a) and glycidyl (meth) acrylate having a chlorine content adjusted to 0.01 to 0.3 mass%; and

and (II-3) reacting the unsaturated carboxylic acid monomer (b) with the base polymer to obtain an N-substituted maleimide polymer having a double bond in a side chain.

4. The process for producing an N-substituted maleimide-based polymer according to claim 3, further comprising the following step (II-1) before the step (II-2): the glycidyl (meth) acrylate is purified so that the chlorine content in the glycidyl (meth) acrylate is 0.01 to 0.3 mass%.

5. The process for producing an N-substituted maleimide-based polymer according to claim 3 or 4, further comprising the following step (II-4) after the step (II-3): reacting a polybasic acid or a polybasic acid anhydride with the N-substituted maleimide-based polymer having a double bond in a side chain.

6. The process for producing an N-substituted maleimide-based polymer according to any one of claims 1 to 5, wherein the residual chlorine content of the N-substituted maleimide-based polymer is 100ppm to 2000ppm based on the total amount of the N-substituted maleimide monomer (a) and glycidyl (meth) acrylate.

7. An N-substituted maleimide polymer comprising a structural unit (A) derived from an N-substituted maleimide monomer and a structural unit (B) represented by the following general formula (B1), (B2) or (B3),

the structural unit (B) contains a structure derived from glycidyl (meth) acrylate,

the amount of residual chlorine in the N-substituted maleimide-based polymer is 100ppm to 2000ppm based on the total mass of the N-substituted maleimide monomer providing the structural unit (A) and the glycidyl (meth) acrylate providing the structural unit (B) as the raw material of the polymer,

[ solution 1]

In the general formula (B1), R ¹ And R ³ Identical or different, represent a hydrogen atom or a methyl group; r ² Represents a divalent linking group; a is 0 or 1;

in the general formula (B2), R ⁴ Represents a hydrogen atom or a methyl group; r ⁵ Represents an ethylenically unsaturated bond-containing group;

in the general formula (B3), R ⁶ Represents a hydrogen atom or a methyl group; r ⁷ Represents an ethylenically unsaturated bond-containing group; x represents a divalent hydrocarbon group.

8. The N-substituted maleimide-based polymer according to claim 7, wherein the acid value of the N-substituted maleimide-based polymer is from 20mgKOH/g to 200mgKOH/g.

9. The N-substituted maleimide-based polymer according to claim 7 or 8, wherein the N-substituted maleimide-based polymer has a double bond equivalent of 300 to 3000 g/equivalent.

10. A curable resin composition comprising the N-substituted maleimide-based polymer according to any one of claims 7 to 9 and a polymerizable compound.