JP2022030396A - Curable polymer compound, and resin composition containing the compound - Google Patents

Abstract

To provide a resin composition that contains a novel polymer compound, and a cured product thereof has sufficient flexibility to be filmed, has high adhesiveness to low-roughness copper foil, and exhibits good dielectric constant and dielectric loss tangent.SOLUTION: Provided is a polymer compound that is a dehydrochlorination condensate of a hydroxyl group included in a random copolymer of styrene and a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule and the random copolymer has a number average molecular weight of 30,000 to 300,000, and a (meth) acrylic acid chloride group, or is a dehydration condensate of a hydroxyl group included in the copolymer, and a (meth) acrylic acid.SELECTED DRAWING: None

Description

The present invention can be easily formed into a film by casting a solution into a substrate, and when used in combination with a radical initiator, a thermal or photocuring reaction is possible, and the cured product has dielectric properties. , Related to polymer compounds with excellent adhesiveness.

The phenoxy resin is a polymer compound having a very large molecular weight obtained by polymerizing a bifunctional epoxy resin and a bifunctional phenol compound. By adding this phenoxy resin, a general epoxy resin composition or radically polymerizable composition can be formed into a film shape, so that it is used in a wide range of fields as an important component of a film-like adhesive, and in particular. In the electric and electronic fields, it is used as an interlayer insulating layer of a printed wiring substrate and a copper foil with a resin.
The cured product of the resin composition to which the phenoxy resin is added has excellent adhesiveness and film forming ability, but has low heat resistance and high dielectric constant and dielectric loss tangent (dielectric constant 3.5 at frequency 1 GHz, dielectric loss tangent 0. It is about 03.) However, the fact is that it cannot be used for electronic equipment applications in which the signal response speed has been increased in recent years. Polymer fluorine compounds (Patent Document 1) such as polytetrafluoroethane (PTFE) and liquid crystal polymers (Patent Document 2) are generally known as resins having excellent dielectric properties, but these resins are different from other resins. The compatibility is extremely low, and the adhesiveness is also insufficient. Patent Document 3 describes a curable polymer compound obtained by reacting 2-vinyl-2-oxazoline or a copolymer of 2-propenyl-2-oxazoline with styrene with (meth) acrylic acid, that is, the present invention. A polymer compound having the same repeating unit as the polymer compound of is described. However, the range of the number average molecular weight of the polymer compound of Patent Document 3 is 1,000 to 20,000, and when the present inventor made a follow-up test, the dielectric loss tangent of the cured product at 10 GHz was about 0.005. In addition, the peel strength for low-roughness copper foil is also very low, and it has been found that it does not sufficiently satisfy the physical properties required for current high-frequency circuit board applications.

Japanese Unexamined Patent Publication No. 2005-001274 Japanese Unexamined Patent Publication No. 2014-060449 U.S. Pat. No. 3,928,499

The present invention has been made in view of the above points, and is a resin composition containing a novel polymer compound, and the cured product thereof has sufficient flexibility to be formed into a film and has low roughness. It is an object of the present invention to provide a resin composition having high adhesiveness to a copper foil and exhibiting a dielectric constant and a dielectric loss tangent.

As a result of diligent studies, the present inventors have found that the above problems can be solved by using a resin composition containing a polymer compound having a specific structure having a specific number average molecular weight, and completed the present invention. ..
That is, the present invention
(1) A random copolymer of styrene and a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule, and having a number average molecular weight of 30,000 to 300,000. The following formula (1), which is a dehydrocondensation product of the hydroxyl group of the copolymer and a (meth) acrylic acid chloride group, or a dehydration condensation product of the hydroxyl group of the copolymer and (meth) acrylic acid.

(In the formula, R ₁ and R ₃ each independently represent a hydrogen atom or a methyl group. R ₂ represents an alkylene group having 2 to 4 carbon atoms. M and n are average values of the number of repeating units, respectively. A polymer compound represented by (), which independently represents a real number in the range of 1 to 2,000.
(2) The polymer compound according to (1) above, wherein the values of m and n satisfy the relationship of 0.001 ≦ n / (m + n) ≦ 0.05.
(3) A resin composition containing the polymer compound and radical initiator according to the preceding paragraph (1) or (2).
(4) The resin composition according to (3) above, which contains a radically reactive monomer having two or more functional groups in one molecule.
(5) The resin composition according to (4) above, wherein the radically reactive monomer is a maleimide compound.
(6) A film-like adhesive comprising the resin composition according to any one of the preceding paragraphs (3) to (5), or (7) the resin according to any one of the preceding paragraphs (3) to (5). The composition, or the cured product of the film-like adhesive according to (6) above.
Regarding.

The resin composition in which the radical initiator is used in combination with the polymer compound of the present invention can be made into a cured product having excellent dielectric properties, adhesiveness and water resistance by applying heat or light energy.

Hereinafter, embodiments of the present invention will be described.
The polymer compound represented by the above formula (1) of the present invention is a random copolymer of styrene and a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule, and has a number average molecular weight. A dehydrochloride condensate of a hydroxyl group having a random copolymer of 30,000 to 300,000 and a (meth) acrylic acid chloride group, or a hydroxyl group of the random copolymer and a (meth) acrylic acid. It is a dehydration condensate.
The description of "(meth) acrylic acid" in the present specification means both acrylic acid and methacrylic acid.

First, a random copolymer (hereinafter, the random copolymer is also simply referred to as “copolymer”) which is an intermediate raw material of the polymer compound of the present invention will be described.
The copolymer has the following formula (2) in which a polymerizable double bond, an amide bond, a polymerizable double bond of a compound having a hydroxyl group, and a vinyl group of styrene are randomly copolymerized in one molecule. It is a compound represented by (a compound having a structure represented by the formula (2)), and R ₁ , R ₂ , m and n in the formula (2) are R ₁ , R ₂ , m in the formula (1). And n have the same meaning.

Specific examples of the compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule include N- (2-hydroxyethyl) acrylamide, N- (2-hydroxyethyl) methacrylamide, and N- (3-). Examples thereof include hydroxypropyl) acrylamide, N- (3-hydroxypropyl) methacrylicamide, N- (4-hydroxybutyl) acrylamide, N- (4-hydroxybutyl) methacrylicamide, and the like, and in particular, N- (2-hydroxyethyl). ) Amide is preferred.

The method of copolymerizing styrene with a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule is not particularly limited as long as it is a known method, for example, bulk polymerization, solution polymerization, emulsion polymerization and suspension. Polymerization and the like can be mentioned.

Examples of the solvent that can be used for solution polymerization include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, propylene glycol monomethyl ether acetate, N-methylpyrrolidone, N, N-dimethylformamide and γ-butyrolactone. Be done. Water and a surfactant are usually used for emulsion polymerization and suspension polymerization, and the copolymerization reaction is carried out in a state where the raw material components are emulsified or suspended in water.

The copolymerization reaction may be any of radical polymerization, cationic polymerization and anionic polymerization. In the case of radical polymerization, it is preferable to use a radical polymerization initiator. Specific examples of the radical polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), and 2,2'-azobis (2,4-dimethylvalero). Nitrile), 1,1'-azobis (cyclohexane-1-carbonitrile, 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, hydrogen peroxide, di-t-butyl Examples thereof include peroxide, dicumyl peroxide and benzoyl peroxide.
The blending amount of the radical polymerization initiator is usually 0.001 to 5 parts by mass with respect to 100 parts by mass of the raw material component of the copolymer. The polymerization temperature is usually 50 to 250 ° C., preferably 60 to 200 ° C., and the polymerization time is usually 0.5 to 30 hours, preferably 1 to 20 hours. The radical polymerization reaction is preferably carried out in a nitrogen gas atmosphere in order to prevent polymerization inhibition due to oxygen in the air.

Specific examples of the cationic polymerization initiator include inorganic acids such as sulfuric acid and hydrochloric acid, organic acids such as CF ₃ COOH and CCl ₃ COOH, and superacids such as CF ₃ SO ₃ H and HClO ₄ . Specific examples of the anionic polymerization initiator include butyl lithium, Na-naphthalene complex, alkali metal, alkyl lithium compound, sodium amide, Grignard reagent, lithium alkoxide and the like. However, since the ionic initiator used for cationic polymerization or anionic polymerization may remain in the copolymer even after the polymerization reaction and adversely affect the dielectric properties and insulating properties, the polymer compound of the present invention may be used. The synthesis of the copolymer as an intermediate raw material is preferably carried out by radical polymerization.
The blending amount of the cationic polymerization initiator or the anionic polymerization initiator is usually 0.01 to 5 parts by mass with respect to 100 parts by mass of the raw material component of the copolymer. The polymerization temperature is usually 40 to 150 ° C., preferably 50 to 120 ° C., and the polymerization time is usually 0.5 to 20 hours, preferably 1 to 15 hours.

The number average molecular weight of the copolymer as an intermediate raw material of the polymer compound of the present invention is usually 25,000 to 300,000, preferably 30,000 to 200,000.
In order to obtain a copolymer having a number average molecular weight within the above range, it is preferable to adjust the amount of the initiator used in synthesizing the copolymer to an appropriate amount. The amount of the initiator required to obtain a copolymer having a number average molecular weight within the above range is also the blending ratio of the compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule and styrene. Although it cannot be said unconditionally, it is generally known that a polymer having a large molecular weight can be obtained by reducing the amount of the initiator, and a polymer having a desired molecular weight can be obtained within the above-mentioned compounding amount. The amount of the initiator to be compounded may be selected.

The amount (mass) of styrene used in synthesizing a copolymer as an intermediate raw material for the polymer compound of the present invention is usually the mass of a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule. It is 20 to 1500 times, preferably 24 to 332 times. By setting the usage ratio of the raw material of the copolymer in the above range, the polymer compound of the present invention in which the cured product exhibits excellent dielectric properties (low dielectric constant and low dielectric loss tangent) can be obtained.

The polymer compound of the present invention has a hydroxyl group (the hydroxyl group specified in the formula (2)) of the copolymer and has a polymerizable double bond, an amide bond and a hydroxyl group in one molecule as a raw material. By the dehydration condensation reaction between the hydroxyl group of the compound (which is the hydroxyl group of the compound) and the chloride group of the (meth) acrylic acid chloride, or the hydroxyl group of the copolymer and the (meth) acrylic acid. can get.

The ratio of the copolymer and (meth) acrylic acid chloride or (meth) acrylic acid used in synthesizing the polymer compound of the present invention is not particularly limited, but (meth) acrylic acid chloride or (meth) acrylic acid chloride or (meth) acrylic acid chloride with respect to the hydroxyl group of the copolymer. If (meth) acrylic acid is excessive or insufficient, it remains unreacted in the polymer compound (meth) acrylic acid chloride or (meth) acrylic acid, or (meth) acrylic acid chloride or methacrylic acid. Since the hydroxyl group remaining without reacting with the polymer may adversely affect various properties of the cured product, it is possible to use (meth) acrylic acid chloride or (meth) acrylic acid in the same amount as the hydroxyl group of the copolymer. preferable.

The reaction between the copolymer and (meth) acrylic acid chloride may be carried out by adding (meth) acrylic acid chloride to the organic solvent solution of the copolymer under stirring. The organic solvent that can be used here is not particularly limited as long as it can dissolve the copolymer and (meth) acrylic acid chloride, and the copolymer as an intermediate raw material is contained in a solvent that can dissolve (meth) acrylic acid chloride. When synthesized in, the copolymer solution after the polymerization reaction may be used as it is. The concentration of the copolymer solution to be subjected to the reaction with (meth) acrylic acid chloride is usually 10 to 90% by mass, preferably 20 to 80% by mass. The reaction temperature is usually 30 to 120 ° C., preferably 40 to 110 ° C., and the reaction time is usually 0.5 to 4 hours, preferably 1 to 3 hours.

Since the reaction between the copolymer and (meth) acrylic acid chloride is a dehydrochloric acid reaction, a tertiary amine such as triethylamine or pyridine is previously added to the reaction solution in order to trap the generated hydrochloric acid and further promote the reaction. It is preferable to add it. The amount of the tertiary amine used is preferably equimolar to 4-fold molar with (meth) acrylic acid chloride, more preferably equimolar to 3-fold molar. Hydrochloric acid generated during the reaction precipitates as an amine hydrochloride and can be removed by filtration after the reaction. Further, the excess tertiary amine can be distilled off from the system under heating and reduced pressure after filtration.

Examples of the reaction between the copolymer and (meth) acrylic acid include conventionally known esterification reactions, for example, a method of heating and stirring the copolymer and (meth) acrylic acid in the presence of a catalyst. Since the reaction between the copolymer and (meth) acrylic acid is a dehydration reaction, it is preferable to carry out the reaction while azeotropically distilling water from the reaction system. Therefore, toluene, xylene and acetic acid which are not completely mixed with water are used. It is preferable to carry out the reaction using a solvent such as ethyl, butyl acetate and methyl isobutyl ketone. The amount of the solvent used is preferably an amount such that the concentration of the raw material component of the polymer compound is 20 to 80% by mass.
Examples of the catalyst used in the esterification reaction include acidic catalysts such as sulfuric acid, methanesulfonic acid and p-toluenesulfonic acid, and the amount used thereof is based on the total mass of the raw material components and the solvent of the polymer compound used in the reaction. Therefore, 0.1 to 5% by mass is preferable. The reaction temperature is usually 50 to 150 ° C., preferably 60 to 140 ° C., and the reaction time is usually 0.5 to 4 hours, preferably 1 to 3 hours.

Further, in order to prevent the polymerization reaction between the (meth) acryloyl groups in the polymer compound during storage of the polymer compound of the present invention, it is possible to add a small amount of a polymerization inhibitor to the polymer compound solution after the completion of the synthesis reaction. preferable. Specific examples of the polymerization inhibitor include hydroquinone, paramethoxyphenol, methylhydroquinone, di-t-butylhydroxytoluene, t-butylhydroquinone, 2-t-butyl-1,4-benzoquinone, 1,4-benzoquinone, 1 , 1-diphenyl-2-picrylhydrazyl free radical, 6-t-butyl-2,4-xylenol, 4-t-butylpyrocatechol, 2,6-di-t-butylphenol, 2,6-di- Examples thereof include t-butyl-p-cresol and phenothiazine.

The range of the number average molecular weight of the polymer compound of the present invention thus obtained is preferably 30,000 to 300,000, more preferably 30,000 to 250,000. If the molecular weight is extremely smaller than the above range, the adhesiveness to the low-roughness copper foil is low, and if it is extremely large, the viscosity is high and coating or the like may be difficult.
The molecular weight in the present specification means a value calculated in terms of polystyrene based on the measurement result of GPC.

The resin composition of the present invention contains the polymer compound of the present invention and a radical initiator. The radical initiator is not limited to either a thermal radical initiator or a photoradical initiator, and a plurality of radical initiators may be used in combination.
Preferred thermal radical initiators include, for example, benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di (t-butylper). Oxy) Hexin-3, di-t-butyl peroxide, t-butyl cumyl peroxide, α, α-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (T-butylperoxy) hexane, dicumyl peroxide, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis (t-butylperoxy) butane, 2,2-bis Peroxides such as (t-butylperoxy) octane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di (trimethylsilyl) peroxide and trimethylsilyltriphenylsilyl peroxide can be mentioned.

Examples of preferred photoradical initiators are benzoins such as benzoin, benzoin methyl ether and benzoin ethyl ether and their alkyl ethers; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone. Anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone and 2-chlorothioxanthone; Ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1-one and 2-benzyl-2-dimethyl Amino-1- (4-morpholinophenyl) -butanone-1; acylphosphine oxides, xanthons and the like can be mentioned.

The content of the radical initiator in the resin composition of the present invention is usually 0.1 to 10 parts by mass with respect to 100 parts by mass in total of the resin components such as the polymer compound and the radical-reactive monomer which is an optional component described later. It is preferably 0.1 to 8 parts by mass.

A radical reactive monomer may be used in combination with the resin composition of the present invention. By using a radically reactive monomer in combination, the reactivity of the resin composition of the present invention and the heat resistance of the cured product can be improved. The radically reactive monomer preferably has two or more functional groups, and specific examples thereof include ethylene glycol dimethacrylate, diethyleneglucoldimethacrylate, tierielenglucoldimethacrylate, and 1,4-butanedioldi. Methacrylate, neopentylglucol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, glycerin dimethacrylate, 2-hydroxy-3-acryloyloxypropylmethacrylate, ethylene oxide adduct methacrylate of bisphenol A , Trimethylolpropantrimethacrylate, tricyclodecanedimethanol dimethacrylate, glycerindimethacrylate, trimethylpropantrimethacrylate, ethoxylated isocyanuric acid triacrylate, ε-caprolactone-modified tris- (2-acryloxyethyl) isocyanurate, pentaerythritol Triacrylate, ditrimethylolpropanetetraacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, triallyl isocyanurate, triallyl cyanurate, divinylbenzene, divinyl isophthalate, N-phenyl-maleimide, N-phenyl-methylmaleimide, N-phenyl-chloromaleimide, Np-chlorophenyl-maleimide, Np-methoxyphenyl-maleimide, Np-methylphenyl-maleimide, Np- Nitrophenyl-maleimide, Np-phenoxyphenyl-maleimide, Np-phenylaminophenyl-maleimide, Np-phenoxycarbonylphenyl-maleimide, 1-maleimide-4-acetoxysuccinimide-benzene, 4-maleimide-4 '-Acetoxysuccinimide-diphenylmethane, 4-maleimide-4'-acetoxysuccinimide-diphenylether, 4-maleimide-4'-acetamide-diphenylether, 2-maleimide-6-acetamide-pyridine, 4-maleimide-4'-acetamide-diphenylmethane And Np-phenylcarbonylphenyl-maleimide N-ethylmaleimide, N-2.6-xysilyl maleimide, N-cyclohexylmaleimide, N-2,3-xysilyl Examples thereof include maleimide, xylylmaleimide, 2,6-xylenemaleimide and 4,4'-bismaleimide diphenylmethane, but those having a maleimide group as a functional group (maleimide compound) are preferable.
Only one kind of these radical-reactive monomers may be used, or two or more kinds thereof may be mixed and used.

An organic solvent may be used in combination with the resin composition of the present invention. Specific examples of the organic solvent include aromatic solvents such as toluene and xylene, ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate and propylene glycol monobutyl ether. Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone, lactones such as γ-butyrolactone and γ-valerolactone, N-methylpyrrolidone (NMP), N, N-dimethylformamide (DMF), N, Examples thereof include amide-based solvents such as N-dimethylacetamide and N, N-dimethylimidazolidinone, and sulphons such as tetramethylene sulphon. The content of the organic solvent in the resin composition of the present invention is usually 90% by mass or less, preferably 30 to 80% by mass in the resin composition.

A polymerization inhibitor may be used in combination with the resin composition of the present invention in order to improve storage stability. The polymerization inhibitor that can be used in combination is not particularly limited as long as it is generally known, and for example, quinones such as hydroquinone, methylhydroquinone, p-benzoquinone, chloranil and trimethylquinone, aromatic diols and dit-butyl. Hydroquinone and the like can be mentioned.

The resin composition of the present invention can be used by blending an amount of a filler or an additive within a range that does not impair the original performance for the purpose of imparting desired performance according to the intended use. The filler may be in the form of fibers or powder, and examples thereof include silica, carbon black, alumina, talc, mica, glass beads, and hollow glass spheres.

A flame-retardant compound, an additive, or the like can be used in combination with the resin composition of the present invention. These are not particularly limited as long as they are generally used. For example, flame-retardant compounds include bromine compounds such as 4,4-dibromobiphenyl, phosphate esters, melamine phosphate, phosphorus-containing epoxy resins, nitrogen compounds such as melamine and benzoguanamine, oxazine ring-containing compounds, silicon-based compounds and the like. Can be mentioned. Additives include UV absorbers, antioxidants, photopolymerization initiators, optical brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, defoaming agents, dispersants, leveling agents, brighteners. Etc., it is also possible to use them in combination as desired.

The resin composition of the present invention can be applied or impregnated on various substrates for use. For example, when a thermal radical initiator is used, it is applied on a PET film as an interlayer insulating layer of a multilayer printed circuit board, applied on a polyimide film as a coverlay, and applied on a copper foil to be a resin. It can be used as an attached copper foil. Further, by impregnating glass cloth, glass paper, carbon fiber, various non-woven fabrics, etc., it can be used as a prepreg for a printed wiring board or CFRP. Further, it can be used as various resists by using a photoradical initiator.

The interlayer insulating layer, coverlay, copper foil with resin, prepreg, and the like of the present invention can be made into a cured product by heating and pressure molding with a hot press machine or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to these examples.

Example 1 (Synthesis of the polymer compound of the present invention)
(Step 1) Synthesis of copolymer represented by the following formula (3) 39 parts of styrene, N- (in a flask equipped with a thermometer, a cooling tube, a nitrogen gas introduction tube, and a stirrer) 2-Hydroxyethyl) 1 part of acrylamide, 0.1 part of benzoyl peroxide and 10 parts of propylene glycol monomethyl ether acetate (PGMEA) were added and reacted at 130 to 140 ° C. in a nitrogen atmosphere for 5 hours to formulate the following formula (3). A PGMEA solution of the copolymer 1 represented by the above was obtained. The amount of copolymer 1 calculated by heating a part of the PEGMEA solution under reduced pressure to remove the solvent and unreacted styrene as the solid content is 35.8 parts, and the amount of unreacted styrene is 4. Considering that it was .2 parts, the obtained copolymer was a copolymer of 34.8 parts of styrene and 1 part of N- (2-hydroxyethyl) acrylamide. The number average molecular weight of the samples used for the measurement of the dry mass was 48,000, and the weight average molecular weight was 140,000. From the copolymerization ratio of styrene and N- (2-hydroxyethyl) acrylamide and the number average molecular weight, the value of m in the following formula (3) is calculated to be 449, and the value of n is calculated to be 11.

(Step 2) Synthesis of the polymer compound (polymer compound 1) of the present invention represented by the following formula (4) From the PGMEA solution of the copolymer 1 obtained in the step 1, unreacted styrene is heated under reduced pressure. After distilling off with PGMEA, PGMEA was added to obtain 138 parts of a 25% by mass solution of the copolymer 1. To this solution was added 5 parts of triethylamine, 0.91 part of methacrylic acid chloride was added at 60 ° C. with stirring, and the mixture was reacted for 1 hour. The reaction solution is pressurized and filtered through a filter paper having a particle diameter of 1 micron to remove triethylamine hydrochloride, and excess triethylamine and PGMEA are distilled off from the filtrate by a rotary evaporator to adjust the amount of PGMEA as described below. 146 parts of a solution containing 25% by mass of the polymer compound (polymer compound 1) of the present invention represented by the formula (4) was obtained. The obtained polymer compound 1 had a number average molecular weight of 50,000 and a weight average molecular weight of 148,000.

Comparative Example 1
(Step 3) Synthesis of copolymer (copolymer 2) represented by the above formula (3) In Example 1, the amount of styrene used was 37.5 parts, and N- (2-hydroxyethyl) acrylamide was used. A PGMEA solution of the copolymer 3 represented by the above formula (3) was obtained according to step 1 except that the amount was changed to 2.5 parts. The amount of the copolymer 3 calculated by heating a part of the PEGMEA solution under reduced pressure to remove the solvent and the unreacted styrene as the solid content is 35.5 parts, and the unreacted styrene is 4 parts. Considering that it was .5 parts, the obtained copolymer was a copolymer of 33 parts of styrene and 2.5 parts of N- (2-hydroxyethyl) acrylamide. The number average molecular weight of the samples used for the measurement of the dry mass was 42,000, and the weight average molecular weight was 124,000. From the copolymerization ratio of styrene and hydroquinone monomethacrylate and the number average molecular weight, the value of m in the formula (3) is calculated to be 375, and the value of n is calculated to be 26.

(Step 4) Synthesis of Comparative Polymer Compound (Polymer Compound 2) Represented by the Formula (4) The copolymer 1 was changed to the copolymer 2 obtained in Step 3 to obtain a methacrylate chloride. According to Step 2, 148 parts of a solution containing 25% by mass of the comparative polymer compound (polymer compound 2) represented by the above formula (4) was obtained except that the amount was set to 2.26. The obtained polymer compound 2 had a number average molecular weight of 44,000 and a weight average molecular weight of 131,000.

Comparative Example 2
(Step 5) Synthesis of copolymer represented by the above formula (3) In Example 1, the above-mentioned step 1 is followed except that the amount of benzoyl peroxide used is changed to 1 part. A PGMEA solution of the copolymer 3 represented by the formula (3) was obtained. The amount of the copolymer 3 calculated by heating a part of the PEGMEA solution under reduced pressure to remove the solvent and unreacted styrene as the solid content is 36.6 parts, and the amount of unreacted styrene is 3. Considering that it was .4 parts, the obtained copolymer was a copolymer of 35.6 parts of styrene and 1 part of N- (2-hydroxyethyl) acrylamide. The number average molecular weight of the samples used for the measurement of the dry mass was 13,000, and the weight average molecular weight was 41,000. From the copolymerization ratio of styrene and hydroquinone monomethacrylate and the number average molecular weight, the value of m in the formula (3) is calculated to be 122, and the value of n is calculated to be 3.

(Step 6) Synthesis of comparative polymer compound (polymer compound 3) represented by the above formula (4) In step 2, except that the copolymer 1 was changed to the copolymer 3 obtained in step 5. Similarly, 148 parts of a solution containing 25% by mass of the comparative polymer compound (polymer compound 3) represented by the above formula (4) was obtained. The obtained polymer compound 3 had a number average molecular weight of 13,500 and a weight average molecular weight of 42,000.

Example 2 (Preparation of the resin composition of the present invention)
The resin composition 1 of the present invention is obtained by adding 0.05 part of dicumyl peroxide as a radical initiator to 10 parts of the PGMEA solution of the polymer compound 1 of the present invention obtained in Example 1 and mixing them uniformly. Obtained.

Comparative Examples 3 and 4 (Preparation of resin composition for comparison)
Comparative Example Resin Composition 2; I got 3.

(Evaluation of Dielectric Characteristics of Cured Resin Composition)
Using an applicator, the resin composition 1 of the present invention and the resin compositions 2 and 3 of the present invention obtained in Examples 2 and Comparative Examples 3 and 4 were placed on a mirror surface of a copper foil having a thickness of 18 μm to a thickness of 280 μm. A copper foil having a film-like adhesive made of a resin composition was obtained by applying the above coatings and heating at 90 ° C. for 10 minutes to dry the solvent. The film-like adhesive on the copper foil obtained above was heat-cured at 180 ° C. for 1 hour using a vacuum oven, and then immersed in an etching solution to remove the copper foil. From the resin composition of No. 3, cured products of a film-like adhesive having a thickness of 70 μm that could be handled as a film were obtained. However, the cured product obtained from the resin composition of Comparative Example 4 was very brittle and could not be treated as a film. The dielectric constant and the dielectric loss tangent at 10 GHz of the cured product obtained above were measured by a cavity resonance method using a network analyzer 8719ET (manufactured by Agilent Technologies). The results are shown in Table 1.

(Evaluation of adhesive strength of cured product of resin composition)
Using an applicator, the resin composition 1 of the present invention and the resin compositions 2 and 3 of the present invention obtained in Examples 2 and Comparative Examples 3 and 4 were subjected to a low-roughness copper foil (CF-) for high frequency with a thickness of 12 μm. T4X-SV: manufactured by Fukuda Metal Foil Powder Co., Ltd.) is coated on the mat surface to a thickness of 50 μm, and heated at 90 ° C. for 10 minutes to dry the solvent to obtain a film-like adhesive consisting of a resin composition. Obtained a copper foil to have. The matte surface of the same copper foil as described above is superposed on the adhesive surface of the copper foil with resin obtained above, and heat-cured at a pressure of 3 MPa in a vacuum press and a temperature of 180 ° C. for 1 hour, and then between the copper foils. The 90 ° peeling strength (adhesive strength) was measured using an autograph AGX-50 (manufactured by Shimadzu Corporation). The results are shown in Table 1.

As described above, the polymer compound of the present invention formed a flexible film when cured with a radical initiator, and exhibited further excellent dielectric properties and adhesiveness.

Claims (7)

A hydroxyl group of a random copolymer of styrene and a compound having a polymerizable double bond, an amide bond and a hydroxyl group in one molecule and having a number average molecular weight of 30,000 to 300,000. The following formula (1), which is a dehydrocondensation product of a (meth) acrylic acid chloride group or a dehydration condensate of a hydroxyl group of the copolymer and (meth) acrylic acid.

(In the formula, R ₁ and R ₃ each independently represent a hydrogen atom or a methyl group. R ₂ represents an alkylene group having 2 to 4 carbon atoms. M and n are average values of the number of repeating units, respectively. A polymer compound independently represented by a real number in the range of 1 to 2,000.). The polymer compound according to claim 1, wherein the values of m and n satisfy the relationship of 0.001 ≦ n / (m + n) ≦ 0.05. A resin composition containing the polymer compound and radical initiator according to claim 1 or 2. The resin composition according to claim 3, which comprises a radically reactive monomer having two or more functional groups in one molecule. The resin composition according to claim 4, wherein the radically reactive monomer is a maleimide compound. A film-like adhesive comprising the resin composition according to any one of claims 3 to 5. The resin composition according to any one of claims 3 to 5, or the cured product of the film-like adhesive according to claim 6.