JP2015227396A - Resin composition for vibration damping material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for vibration damping material which exhibits an excellent vibration damping property in a wide temperature range, has excellent color development, and can prevent the slip of a coating film sufficiently at the time of forming the coating film.SOLUTION: A resin composition for vibration damping material comprises polymer emulsion, the composition further comprising plasticizer and vinyllactam polymer.

Description

The present invention relates to a resin composition for vibration damping materials.

In order to attenuate vibrations in various structures and prevent vibration and noise caused by the vibrations, vibration damping materials are used. The vibration damping material is used, for example, under an indoor floor of an automobile, and is also widely used for railway vehicles, ships, aircraft, electrical equipment, building structures, construction equipment, and the like. As such a vibration damping material, a coating-type resin composition (paint) for vibration damping material has been developed. For example, a paint formed by spraying on a corresponding portion by spraying or applying by any other method. In addition, various types of blends capable of obtaining a vibration damping effect and a sound insulation effect such as sound insulation and sound absorption have been proposed (see, for example, Patent Documents 1 to 5).

Japanese Patent No. 4172536 Japanese Patent No. 3318593 International Publication No. 01/40391 Japanese Patent No. 4465023 JP 2005-281576 A

As described above, resin compositions having various configurations are disclosed for use in vibration damping materials, but in such applications, stable vibrations are not affected by changes in environmental temperature. It is required to exhibit a damping property. Further, there is a demand for a resin composition that has excellent color developability, can sufficiently prevent sliding of the coating film during coating film formation (slip property of the coating film), and can form a coating film having an excellent appearance. It has been a challenge to develop a resin composition that meets such requirements.

The present invention has been made in view of the above situation, and exhibits excellent vibration damping in a wide temperature range, excellent color development, and vibration that can sufficiently prevent the coating film from slipping during coating film formation. It aims at providing the resin composition for damping materials.

The present inventor has made various studies on resin compositions for vibration damping materials, and a composition containing a polymer emulsion and further containing a plasticizer and a vinyl lactam polymer has vibrations having various vibration amplitudes and frequencies in a wide temperature range. Excellent vibration damping performance (mechanical vibration, sound waves, etc.), excellent color developability, sufficiently prevented slipping of the coating film during coating formation, excellent vibration damping and appearance The present inventors have found that a vibration damping material can be formed and have reached the present invention.

That is, this invention is a resin composition for vibration damping materials containing a polymer emulsion, The said composition is a resin composition for vibration damping materials containing a plasticizer and a vinyl lactam polymer further.
The present invention is also a vibration damping material obtained by using the resin composition for vibration damping material of the present invention.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

The resin composition for vibration damping material of the present invention includes a polymer emulsion, a plasticizer, and a vinyl lactam polymer, and can exhibit excellent vibration damping performance in a wide temperature range. In addition, a water-soluble polymer is usually added to the paint to improve drainage of the paint film during drying, but when a general water-soluble polymer is added, the slip of the paint film during film formation Sexuality will deteriorate. However, when the resin composition for vibration damping material of the present invention containing a polymer emulsion further contains a vinyl lactam polymer, it is possible to improve drainage of the coating film during drying and to maintain the slip property well. An unexpected effect not found in conventional water-soluble polymers is exhibited. Moreover, since the resin composition for vibration damping material of the present invention is also excellent in color developability, a vibration damping material having excellent appearance can be formed.

The vinyl lactam polymer has the following general formula (1):

(Wherein R represents a hydrogen atom or a methyl group, and preferably represents a hydrogen atom. M is an integer of 1 to 3, preferably 1 or 2, and more preferably 1). It is preferable that it is a polymer which has 1 type, or 2 or more types of the N-vinyl lactam structure represented as an essential structural unit (repeating unit). Examples of such vinyl lactam polymers include poly (N-vinyl-2-pyrrolidone), poly (N-vinyl-5-methyl-2-pyrrolidone), poly (N-vinyl-2-piperidone), 1 of vinyl lactam monomers such as poly (N-vinyl-6-methyl-2-piperidone), poly (N-vinyl-ε-caprolactam), poly (N-vinyl-7-methyl-ε-caprolactam) Homopolymers obtained by polymerizing seeds, copolymers obtained by copolymerizing two or more kinds of vinyl lactam monomers, one or more kinds of vinyl lactam monomers and other monomers The copolymer obtained by copolymerizing is mentioned. Among these, the vinyl lactam polymer is more preferably a homopolymer, and particularly preferably poly (N-vinyl-2-pyrrolidone) (also referred to as polyvinylpyrrolidone).

The vinyl lactam polymer preferably has a K value of 10 or more, more preferably 15 or more, still more preferably 20 or more, and particularly preferably 25 or more. The K value is preferably 120 or less, more preferably 100 or less, still more preferably 80 or less, and particularly preferably 60 or less.
The K value can be calculated by applying a relative viscosity value (25 ° C.) measured by a capillary viscometer that correlates with the molecular weight to the following Fikentscher equation.
K = (1.5 log η _rel −1) / (0.15 + 0.003c) + (300 clog η _rel + (c + 1.5 clog η _rel ) ² ) ^1/2 /(0.15c+0.003c ² )
η _rel : Relative viscosity of vinyl lactam polymer aqueous solution with respect to water c: Vinyl lactam polymer concentration (%) in vinyl lactam polymer aqueous solution

The vinyl lactam polymer can be obtained by polymerizing a monomer component essentially containing a vinyl lactam monomer in a reaction solution.
The vinyl lactam monomer has the following general formula (2):

(Wherein R and m are the same as above), and examples thereof include vinyl pyrrolidone, vinyl piperidone, vinyl caprolactam, and among them, vinyl pyrrolidone is preferable. As the vinyl lactam monomer, one or more of these can be used.

In the monomer component essentially comprising the vinyl lactam monomer, a monomer other than the vinyl lactam monomer may or may not be included. As the usage-amount of a body, it is preferable that it is 1.0 mol% or more with respect to the monomer component whole quantity, for example. The amount used is preferably 10.0 mol% or more, more preferably 20.0 mol% or more, still more preferably 40.0 mol% or more, still more preferably 60.0 mol% or more, and 80.0 mol%. % Or more is particularly preferable, and 100 mol% is most preferable.

The monomer other than the vinyl lactam monomer is not particularly limited as long as it is a monomer copolymerizable with the vinyl lactam monomer. For example, the following compounds (1) to (13) 1 type, or 2 or more types can be used.
(1) (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, hydroxyethyl (meth) acrylate; ) (Meth) acrylamide derivatives such as (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide; (3) dimethylaminoethyl (meth) acryl Basic unsaturated monomers such as acid esters, dimethylaminoethyl (meth) acrylamide, vinylpyridine, and vinylimidazole, and salts or quaternized products thereof; (4) vinylamides such as vinylformamide, vinylacetamide, and vinyloxazolidone; (5) (Meth) acrylic acid, itaconic acid, male Carboxyl group-containing unsaturated monomers such as acid and fumaric acid and salts thereof; (6) unsaturated acid anhydrides such as maleic anhydride and itaconic anhydride; and (7) vinyl such as vinyl acetate and vinyl propionate. Esters; (8) Vinyl ethylene carbonate and derivatives thereof; (9) Styrene and derivatives thereof; (10) (Meth) acrylic acid-2-sulfonic acid ethyl ester and derivatives thereof; (11) Vinyl sulfonic acid and derivatives thereof; (12) Vinyl ethers such as methyl vinyl ether, ethyl vinyl ether and butyl vinyl ether; (13) Olefins such as ethylene, propylene, octene and butadiene. Among these, (1) to (8) are preferable from the viewpoint of copolymerization with vinyl lactam monomers such as vinylpyrrolidone and vinylcaprolactam represented by the general formula (2).

The resin composition for vibration damping material of the present invention comprises a polymer emulsion, a plasticizer, and a vinyl lactam polymer having a solid content of 100% by mass in a composition of 100% by mass of the vinyl lactam polymer. It is preferable to contain a polymer.
The content of the vinyl lactam polymer is more preferably 0.2% by mass or more, still more preferably 0.3% by mass or more, still more preferably 0.4% by mass or more, and particularly preferably. It is 0.5 mass% or more. The content is more preferably 9% by mass or less, still more preferably 8% by mass or less, still more preferably 7% by mass or less, and particularly preferably 6% by mass or less.

The resin composition for vibration damping material of the present invention contains a plasticizer. Thereby, the property of the resin composition becomes close to a viscous body, and the vibration damping property (loss coefficient η) is increased.
The plasticizer may be any component that can improve the vibration damping property of the vibration damping material resin composition, and includes aromatic hydrocarbons, heteroaromatic compounds, organic acids, and modified products thereof. It is preferably at least one selected from the group consisting of In other words, one type of these plasticizers may be included, or two or more types may be included.
In the present specification, “at least one selected from the group consisting of aromatic hydrocarbons, heteroaromatic compounds, organic acids, and modified products thereof” means “aromatic hydrocarbons, aromatics”. It is synonymous with “at least one selected from the group consisting of modified hydrocarbons, heteroaromatic compounds, modified heteroaromatic compounds, organic acids, and modified organic acids”.

The plasticizer has a molecular weight of preferably 100 or more, more preferably 120 or more, still more preferably 140 or more, still more preferably 150 or more, and particularly preferably 160 or more. The molecular weight is preferably 4000 or less, more preferably 3000 or less, still more preferably 2000 or less, and particularly preferably 1000 or less. When the molecular weight is within the above range, the compatibility of the plasticizer with the emulsion polymer is more excellent. By setting the molecular weight within the above range, bleeding of the plasticizer and volatilization during heat drying can be prevented, and the vibration damping property of the composition can be further enhanced.

The plasticizer preferably has a polar structure in a ratio of 1 or more with respect to the molecular weight of the plasticizer of 1000, more preferably 1 or more with respect to the molecular weight of 900, and 1 or more with respect to the molecular weight of 800. Is more preferable, it is even more preferable to have one or more with respect to the molecular weight 700, particularly preferable to have one or more with respect to the molecular weight 600, and most preferable to have one or more with respect to the molecular weight 500.
The polar structure is a structure containing a hetero atom, preferably an ester group, a hydroxyl group (the hydroxyl group includes a phenolic hydroxyl group), a nitrile group, an amine group, a carboxyl group, a chloro group, a phosphate group, an amide group, a pyrrolidone. Group, ether (including cyclic ether), thiazole, triazole, and quinoline, more preferably an ester group, a hydroxyl group, and an amine group, still more preferably a hydroxyl group and an amine group, and particularly preferably a hydroxyl group.
For example, if a plasticizer with a molecular weight of 200 has one amine group per molecule, it will have five polar structures when converted to a molecular weight of 1000.
When the plasticizer has the above-mentioned kind of polar structure, the plasticizer is excellent in compatibility with the polymer emulsion, and a coating film without elution of the plasticizer is easily obtained.

The pour point of the plasticizer is preferably −70 ° C. or higher, more preferably −60 ° C. or higher, still more preferably −50 ° C. or higher, and particularly preferably −40 ° C. or higher. Most preferably, it is −30 ° C. or higher. The pour point is preferably 200 ° C. or lower, more preferably 170 ° C. or lower, still more preferably 140 ° C. or lower, particularly preferably 110 ° C. or lower, and 80 ° C. or lower. Is most preferred.
When the plasticizer has a pour point in the above range, the compatibility with the polymer emulsion is excellent, and the peak temperature (also referred to as DPT) of the loss coefficient of the resin composition for vibration damping material of the present invention containing the polymer emulsion and the plasticizer. It becomes easy to adjust.

Examples of the aromatic hydrocarbons or modified aromatic hydrocarbons as the plasticizer include bis (2-ethylhexyl) phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, and bis (2 -Butoxyethyl), phthalates such as ditridecyl phthalate, trimellitic esters, terephthalates such as bis (2-ethylhexyl) terephthalate, benzoates such as glycol benzoate, styrenated phenols Among them, styrenated phenols are preferable.
Furthermore, p- (p-toluenesulfonylamide) diphenylamine, N-cyclohexyl-p-toluenesulfonamide, 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, alkylated diphenylamine (eg, octylated diphenylamine), Aromatic secondary amines such as N, N′-di-2-naphthyl-p-phenylenediamine, a reaction product of N-phenylbenzenediamine and styrene, 2,4,4-trimethylpentane, 1,3- Guanidines such as diphenylguanidine, N, N′-diphenylguanidine, N, N′-diorthotolylguanidine, thioureas such as N, N′-diphenylthiourea, α, α′-bis (4-aminophenyl) Anilines such as -1,4-diisopropylbenzene and n-butyraldehyde aniline, ethyl-2 Diphenyl acrylates such as cyano-3,3-diphenyl acrylate and octyl-2-cyano-3,3-diphenyl acrylate, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid Benzophenones such as 1,1′-bis (4-hydroxyphenyl) cyclohexane, 2,2′-bis (4-hydroxy-3-methylphenyl) propane, 2,2′-methylenebis (4-methyl-6- t-butylphenol), 2,2'-methylenebis (4-methyl-6-nonylphenol), 2,2'-methylenebis (4-methyl-6-cyclohexylphenol), 2,2'-methylenebis (4-methyl) Phenol), 2,2'-methylenebis (4-propylphenol), 2,2 ' Methylenebis (4-chlorophenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 2,2′-iso Butylidenebis (4,6-dimethylphenol), 2,2'-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 4,4'-thiobisphenol 4,4'-thiobis (3-methyl-6-tert-butylphenol), 4,4'-thiobis (2-methyl-6-tert-butylphenol), 4,4'-methylenebis (2,6-di-) t-butylphenol), 4,4′-methylenebis (2,5-dimethylphenol), 4,4′-methylenebis (2-methyl-5-ethylphenol), 4,4′-methylenebis (2 -Methyl-5-propylphenol), 4,4'-ethylenebis (2,6-di-t-butylphenol), 4,4'-isopropylidenebis (2,6-di-t-butylphenol), 4, 4'-isopropylidenebis (2,7-di-t-butylphenol), 4,4'-butylidenebis (2,6-di-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t -Butylphenol), 4,4'-dihydroxybiphenyl, 1,3,5-trimethyl-2,4,6-tris- (3,5-di-t-butyl-4hydroxybenzyl) -benzene, 1,6- Hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], butylated reaction product of p-cresol and dicyclopentadiene, 1,4-bis ( -Benzoyl-3-hydroxyphenoxy) -butane, 1- [2- {3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy} ethyl] -4- {3- (3,5 -Di-t-butyl-4-hydroxyphenyl) propionyloxy} -2,2,6,6-tetramethylpiperidine, 1,1,3-tris (5-t-butyl-4-hydroxy-2-methylphenyl) ) Butane, 2,5-di-t-butylhydroquinone, 3,9-bis [1,1-dimethyl-2-[(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 4-vinylphenol, tetrakis (methylene-di-t-butyl-4-hydrohydrocinnamate), tri -(3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, pentaerythrityl-tetra [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], tri Ethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene, tetrakis (methylene- 3,5-di-t-butyl-4-hydrohydrocinnamate), phenols such as hydroquinone, naphthol such as 1,5-dihydroxynaphthalene, 5-amino-1-naphthol, 2-amino-6-hydroxynaphthol Kind.

Examples of heteroaromatic compounds or modified products of heteroaromatic compounds include quinolines such as 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, N-cyclohexyl-2- Benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazolyl sulfenamide, N- (t-butyl) -2-benzothiazole sulfenamide, N, N-dicyclohexylbenzothiazole-2-sulfene Amido, 2-mercaptobenzothiazole, benzothiazyl such as dibenzothiazyl sulfide, 2- (2'-hydroxy-5'-methylphenyl) -benzotriazole, 2- (3-t-butyl-5-methyl-2- Hydroxyphenyl) -5-chlorobenzotriazole, 3- [3-t-butyl-5- (5-chloro-2H-) Nzotriazol-2-yl) -4-hydroxyphenyl] octyl propionate, octyl 3- [3-tert-butyl-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate, 2 -[2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- [2′-hydroxy-3 ′-(3,4,5,6-tetrahydrophthalimide) Methyl) -5'-methylphenyl] benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazo Le, 2- (2'-hydroxy-5'-t-octylphenol) benzotriazoles such as benzotriazole, and the like.

Examples of organic acids or modified organic acids include bis (2-ethylhexyl) adipate, diisononyl adipate, diisodecyl adipate, bis (2-butoxyethyl) adipate, tributyl citrate, Citric acid esters such as tributyl acetyl citrate, sebacic acid esters such as dibutyl sebacate, azelaic acid such as dihexyl azelate and dioctyl azelate, stearic acid esters, tricresyl phosphate, and triphenyl phosphate Esters, epoxidized oils such as epoxidized soybean oil, hydroxyalkyl vinyl ethers such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, cyclohexanedimethanol monovinyl ether, glycerin tria Tate, glycerin such as glycerin tripropionate, triethylene glycol dicaprate, poly caprolactone, polyesters such as adipic acid polyester.
Furthermore, organic thioacids such as ditridecyl 3,3′-thiobispropionate and didodecyl 3,3′-thiobispropionate, tris (nonylphenyl) phosphite, diphenylisodecylphosphite, di (nonylphenyl) pentaerythritol Diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) ) Phosphorous acids such as butane triphosphite, triphenyl phosphate, 2-ethylhexyl diphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, cresyl-di-2,6-xylenyl phosphate, 3 , 9-bis (4-nonylphenoxy) ) Tetraoxa-3,9 Jihosufapiro [5.5] phosphoric acid esters such as undecane.

Other plasticizers include polyethers, polybutenes, chlorinated paraffins, and the like.

In this specification, styrenated phenols are organic low molecular weight compounds obtained by using phenols and styrenes as reaction raw materials.
Examples of phenols include polyphenols such as phenol, 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, 1,4-dihydroxybenzene, 1,2,3-trihydroxybenzene, (o -, M-, p-) cresol, 4-t-butylphenol, 4-t-butylcatechol, 4-octylphenol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol, 2, Alkylphenols such as 6-dimethylphenol, 3,4-dimethylphenol and 3,5-dimethylphenol, polycyclic aromatics such as 1-naphthol, 2-naphthol, 1,4-dihydroxynaphthalene and 9,10-anthracenediol (Polyvalent) phenols are mentioned.

Examples of styrenes include styrene, divinylbenzene, α-methylstyrene, vinyltoluene, ethylvinylbenzene, 4-t-butylstyrene, 4-vinylbenzoic acid, and preferably styrene.

The styrenated phenols obtained by reacting these phenols with styrenes are preferably mono (or di, tri) (α-methylbenzyl) phenol obtained by reacting phenol and styrene.
When the styrenated phenol is mono (or di, tri) (α-methylbenzyl) phenol, mono-α-methylbenzylphenol, di-α-methylbenzylphenol, tri-α-methylbenzylphenol 1 type may be included and the mixture containing 2 or more types may be sufficient. In the case of the above two or more kinds of mixtures, the blending ratio thereof is not particularly limited.

When the vibration damping material resin composition of the present invention is an aqueous composition, the plasticizer may be contained in the polymer emulsion contained in the vibration damping material resin composition, or the emulsion in the aqueous solvent. May exist as Such an aqueous resin composition for vibration damping material in which a plasticizer is contained in a polymer emulsion or present as an emulsion in an aqueous solvent is also suitable for the resin composition for vibration damping material of the present invention. This is one of the embodiments.

The resin composition for vibration damping material of the present invention comprises a polymer emulsion, a plasticizer, and a plasticizer of 10 to 90% by mass in 100% by mass of the total solid content of the vinyl lactam polymer described later. It is preferable to include. The content of the plasticizer is more preferably 15% by mass or more, still more preferably 20% by mass or more, and particularly preferably 25% by mass or more. The plasticizer content is more preferably 85% by mass or less, still more preferably 82% by mass or less, and particularly preferably 80% by mass or less.

The polymer emulsion contains an unsaturated carboxylic (acid) monomer, an unsaturated monomer having an aromatic ring, an unsaturated monomer having a nitrogen atom, and an unsaturated carboxylic (acid) monomer. It is preferably obtained by polymerizing a monomer component containing at least one monomer selected from the group consisting of other polymerizable monomers.
The polymer emulsion is more preferably obtained from a monomer component containing an unsaturated carboxylic (acid) monomer, an unsaturated carboxylic (acid) monomer and an unsaturated carboxylic (acid). More preferably, it is obtained from a monomer component containing another monomer copolymerizable with the system monomer. The unsaturated carboxylic (acid) monomer is not particularly limited as long as it is a compound having an unsaturated bond in the molecule and further having a carboxyl group, a salt of the carboxyl group, or an ester derived from the carboxyl group, Among them, it is one of the preferred embodiments of the present invention to contain a compound having a carboxyl group (also referred to as an unsaturated carboxylic acid monomer). Here, the carboxyl group may be an acid anhydride group obtained by dehydration condensation of two carboxyl groups.

The unsaturated carboxylic acid monomer is not particularly limited. For example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, citraconic acid, fumaric acid, maleic acid, maleic anhydride, monomethyl fumarate, monoethyl fumarate , Monomethyl maleate, monoethyl maleate, and the like, and acrylic acid and methacrylic acid are preferable.
Among unsaturated carboxylic (acid) monomers other than unsaturated carboxylic acid monomers, esters or salts derived from acrylic acid, methacrylic acid, acrylic acid, and esters or salts derived from methacrylic acid Is preferred as a monomer.
That is, it is one of the preferable embodiments of the present invention that the polymer emulsion contains a polymer obtained by polymerizing a monomer component containing a (meth) acrylic (acid) monomer.
The (meth) acrylic (acid) monomer means either or both of a (meth) acrylic monomer and a (meth) acrylic monomer.
In the present specification, the (meth) acrylic acid monomer has an acryloyl group or a methacryloyl group, or a group in which a hydrogen atom in these groups is replaced with another atom or atomic group, and It is a monomer having a —COOH group. The (meth) acrylic acid monomer includes acrylic acid and methacrylic acid.
In this specification, the (meth) acrylic monomer has an acryloyl group or a methacryloyl group, or a group in which a hydrogen atom in these groups is replaced with another atom or atomic group, and -COOH A monomer having a structure in which a group is an ester or a salt, or a derivative of such a monomer. The (meth) acrylic monomer includes acrylate and methacrylate.

Among the above (meth) acrylic monomers, monomers having a structure in which the —COOH group is an ester include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, and isopropyl acrylate. , Isopropyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, pentyl acrylate, pentyl methacrylate, isoamyl acrylate, isoamyl methacrylate, hexyl acrylate, hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, Octyl acrylate, octylme Chryrate, isooctyl acrylate, isooctyl methacrylate, nonyl acrylate, nonyl methacrylate, isononyl acrylate, isononyl methacrylate, decyl acrylate, decyl methacrylate, dodecyl acrylate, dodecyl methacrylate, tridecyl acrylate, tridecyl methacrylate, hexadecyl acrylate, hexadecyl Methacrylate, octadecyl acrylate, octadecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, diallyl phthalate, triallyl cyanurate, Echile Glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, diethylene glycol Examples include dimethacrylate, allyl acrylate, allyl methacrylate, isobornyl acrylate, and isobornyl methacrylate. Among them, methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, isobornyl Nyl acrylate and isobornyl methacrylate are preferred. One or more of these monomers can be used as the monomer.

Among the above (meth) acrylic monomers, in the case of a monomer having a structure in which the —COOH group is a salt, the salt is preferably a metal salt, an ammonium salt, an organic amine salt, or the like. As a metal atom which forms a metal salt, for example, a monovalent metal atom such as lithium, sodium or potassium; a divalent metal atom such as magnesium or calcium; or a trivalent metal atom such as aluminum or iron is more preferable. Moreover, as an organic amine salt, alkanolamine salts, such as an ethanolamine salt, a diethanolamine salt, and a triethanolamine salt, and a triethylamine salt are more preferable.

When the monomer component used as the raw material of the polymer emulsion contains a (meth) acrylic acid monomer, the content ratio of the (meth) acrylic monomer is 100% by mass of all monomer components. On the other hand, 0.1-20 mass% is preferable, 0.5-15 mass% is more preferable, 1-10 mass% is still more preferable, and 1-5 mass% is the most preferable. When the content ratio is 0.1% by mass or more, particularly when the resin composition for vibration damping material of the present invention includes a filler such as an inorganic filler described later, dispersibility of the filler is improved, and vibration damping is achieved. More improved.

When the monomer component used as the raw material of the polymer emulsion contains a (meth) acrylic monomer, the content ratio of the (meth) acrylic monomer is based on 100% by mass of all monomer components. 20% by mass or more, preferably 30% by mass or more, more preferably 45% by mass or more, and particularly preferably 60% by mass or more. Moreover, the upper limit of this content rate is not specifically limited, 100 mass% may be sufficient. With such a content ratio of the (meth) acrylic monomer, the polymerization stability is excellent and the glass transition temperature (Tg) can be easily adjusted.

In addition to the unsaturated carboxylic (acid) monomer, the monomer component used as the raw material for the polymer emulsion is an unsaturated monomer having an aromatic ring, an unsaturated monomer having a nitrogen atom, and an unsaturated carboxylic acid. When other monomers copolymerizable with the (acid) monomer are included, it becomes easy to adjust the acid value, Tg, physical properties and the like of the polymer emulsion.
When the resin composition for vibration damping material of the present invention contains a polymer emulsion formed from these monomers, it becomes possible to have excellent heat drying properties in addition to vibration damping properties.

Examples of the unsaturated monomer having an aromatic ring include divinylbenzene, styrene, α-methylstyrene, vinyltoluene, ethylvinylbenzene, and the like. Among them, styrene is preferable.
That is, it is also one preferred embodiment of the present invention that the polymer emulsion is a styrene (meth) acrylic polymer obtained from a monomer component containing styrene.

When the polymer emulsion is a styrene (meth) acrylic polymer, the monomer component as a raw material preferably contains 1 to 90% by mass of styrene in 100% by mass of the monomer component, and 1 to 80% by mass. %, More preferably 1 to 70% by mass, still more preferably 1 to 50% by mass, particularly preferably 5 to 45% by mass, most preferably 10 to 40% by mass. .

Examples of the unsaturated monomer having a nitrogen atom include acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, diacetone acrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-methoxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, Ni-butoxymethyl (meth) acrylamide, etc. are mentioned.
Examples of other monomers copolymerizable with unsaturated carboxylic (acid) monomers include vinyl formate, vinyl acetate, vinyl propionate, vinyl chloride, ethylene, butadiene, and the like.

It is one of the preferred embodiments of the present invention that the polymer emulsion is obtained from a monomer component containing a polar group-containing monomer.
The content of the polar group-containing monomer is preferably 40 to 100% by mass, more preferably 45 to 95% by mass, and 50 to 90% by mass in 100% by mass of the monomer component. More preferably it is. When the content ratio is 40% by mass or more, vibration damping is more sufficiently exhibited.

The polar group in the polar group-containing monomer is not limited as long as it is generally a polar group in an organic compound, but is a group consisting of a carboxylic acid ester, a hydroxyl group, a nitrile group, a carboxyl group, an amide group, and a pyrrolidone group. At least one selected from the group consisting of a carboxylic acid ester, a hydroxyl group, and a carboxyl group is more preferable.

The monomer component forming the polymer emulsion may further contain an unsaturated monomer having a functional group other than the polar group. Examples of the functional group in the unsaturated monomer having a functional group other than the polar group include an epoxy group, a glycidyl group, an oxazoline group, a carbodiimide group, an aziridinyl group, an isocyanate group, a methylol group, a vinyl ether group, a cyclocarbonate group, Examples include alkoxysilane groups.
Examples of the unsaturated monomer having a functional group other than the polar group include glycidyl group-containing unsaturated monomers such as glycidyl (meth) acrylate and acrylic glycidyl ether, which are used alone. Or two or more of them may be used in combination.
The unsaturated monomer having a functional group other than the polar group may be a monofunctional unsaturated monomer having one functional group other than the polar group in one molecule. It may be a polyfunctional unsaturated monomer. Moreover, as long as it has functional groups other than the said polar group, you may have the said polar group.

Examples of the polyfunctional unsaturated monomer include divinylbenzene, ethylene glycol di (meth) acrylate, N-methoxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide, Nn-butoxymethyl ( (Meth) acrylamide, Ni-butoxymethyl (meth) acrylamide, N-methylol (meth) acrylamide, diallyl phthalate, diallyl terephthalate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) ) Acrylate, tetramethylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentylglycol Di (meth) acrylate. These may be used alone or in combination of two or more.

The polymer emulsion preferably has a weight average molecular weight of 500 to 1,500,000. By setting the weight average molecular weight within this range, good heat drying properties can be obtained, and vibration damping can be more fully exhibited without impairing the appearance of the coating film. The weight average molecular weight is more preferably 10,000 or more, still more preferably 20,000 or more, still more preferably 30,000 or more, and particularly preferably 40,000 or more. The weight average molecular weight is more preferably 1,000,000 or less, still more preferably 400,000 or less, still more preferably 300,000 or less, and particularly preferably 200,000 or less.
The weight average molecular weight of the polymer emulsion can be determined by GPC (gel permeation chromatography) measurement under the following measurement conditions.
Measuring instrument: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Molecular weight column: TSK-GEL GMHXL-L and TSK-GELG5000HXL (both manufactured by Tosoh Corporation) are connected in series. Eluent: Tetrahydrofuran (THF)
Standard material for calibration curve: Polystyrene (manufactured by Tosoh Corporation)
Measurement method: The measurement object is dissolved in THF so that the solid content is about 0.2% by mass, and the molecular weight is measured using an object obtained by filtration through a filter as a measurement sample.

The polymer emulsion preferably has a glass transition temperature of −25 to 180 ° C. When a polymer emulsion having such a glass transition temperature is used, vibration damping performance in a practical temperature range of the vibration damping material can be effectively expressed. The glass transition temperature is more preferably −20 ° C. or higher, further preferably −15 ° C. or higher, and particularly preferably −5 ° C. or higher. The glass transition temperature is more preferably 170 ° C. or less, still more preferably 160 ° C. or less, and particularly preferably 150 ° C. or less.
The glass transition temperature (Tg) of the polymer emulsion may be determined based on the knowledge already obtained, and may be controlled by the type and use ratio of the monomer component described later, but theoretically. Can be calculated from the following calculation formula (1).

In the formula, Tg ′ is Tg (absolute temperature) of the polymer. W ₁ ′, W ₂ ′,... Wn ′ are mass fractions of each monomer with respect to all monomer components that are raw materials for the polymer. _{Tg 1, Tg 2, ··· Tg} n is the glass transition temperature (absolute temperature) of homopolymer consisting each monomer component (homopolymer).

The polymer emulsion may contain one kind or two or more kinds of polymers, and when it contains two or more kinds of polymers, it may be an emulsion prepared by multistage polymerization.

The resin composition for vibration damping material of the present invention may contain one kind of polymer obtained by polymerizing the monomer component, or may contain two or more kinds.
When the resin composition for vibration damping material of the present invention contains two or more kinds of polymers formed by polymerizing monomer components, the two kinds of polymers having a glass transition temperature difference of 5 to 100 ° C. are contained therein. It is preferable.
When the difference between the glass transition temperatures of the two types of polymers is 5 ° C. or more and 100 ° C. or less, the temperature range in which high vibration damping properties are sufficiently widened. Thereby, it becomes possible to express a higher vibration damping property in a wide temperature range, and the vibration damping property in a practical range of 10 to 60 ° C. is remarkably improved.
The upper limit of the difference in the glass transition temperature (Tg) is more preferably 90 ° C., still more preferably 80 ° C., still more preferably 60 ° C., particularly preferably 50 ° C., and most preferably 40 ° C. It is. Further, the lower limit of the difference in glass transition temperature (Tg) is more preferably 5 ° C, further preferably 10 ° C, and particularly preferably 15 ° C.

As will be described later, when the resin composition for vibration damping material of the present invention contains two or more types of polymers obtained by polymerizing monomer components, the resin composition for vibration damping material of the present invention contains two or more types of resin compositions. In addition to the case of containing a polymer emulsion, the case of containing a polymer emulsion prepared by multistage polymerization of two or more stages is also included. In the latter case, it is preferable that the difference between the glass transition temperature of the stage having the highest glass transition temperature and the stage having the lowest glass transition temperature is in the above range.

When the resin composition for vibration damping material of the present invention contains two or more kinds of polymers obtained by polymerizing monomer components, at least one of the polymers preferably has a weight average molecular weight of 500 or more, more preferably 1000. It is above, More preferably, it is 2000 or more. The weight average molecular weight is preferably 1.5 million or less, more preferably 1 million or less, further preferably 500,000 or less, still more preferably 300,000 or less, and particularly preferably 200,000 or less. Among them, it is particularly preferably 100,000 or less, and most preferably 50,000 or less.
By using a material having such a weight average molecular weight, the vibration damping property can be further increased.
The weight average molecular weight of the polymer obtained by polymerizing the monomer component can be measured by the above-described method for measuring the weight average molecular weight of the polymer emulsion.

The polymer emulsion contained in the vibration damping material resin composition of the present invention preferably has an SP value (solubility coefficient) of 7 to 13. When the SP value of the polymer is in such a range, the compatibility with the plasticizer is excellent. The SP value is more preferably 7.3 to 12.5, and still more preferably 7.6 to 12.
The SP value of the polymer can be determined by the following Small formula.

In the formula, δ is the SP value of the polymer. Δe ₁ is a calculated value (kcal / mol) of evaporation energy of each monomer component constituting the polymer, and ΣΔe ₁ is a total value of the calculated values of all monomer components constituting the polymer. is there. ΔV _m is a calculated value (ml / mol) of the molecular volume of each monomer component constituting the polymer, and ΣΔV _m is the sum of the calculated values of all the monomer components constituting the polymer. . x is a molar distribution of each component of the monomer constituting the polymer.
Note that normally used calculation values can be used for the evaporation energy of the monomer component and the molecular volume of the monomer component.
Thus, the SP value of the polymer can be adjusted by adjusting the type of monomer to be constituted and the component ratio thereof.

In the present invention, the viscosity of the polymer emulsion is not particularly limited, but is preferably 10 mPa · s or more, more preferably 15 mPa · s or more, still more preferably 20 mPa · s or more, and particularly preferably 100 mPa · s. That's it. Moreover, this viscosity becomes like this. Preferably it is 10000 mPa * s or less, More preferably, it is 8000 mPa * s or less, More preferably, it is 6000 mPa * s or less. With such a viscosity, the dispersibility of the pigment is improved, and vibration damping can be more fully exhibited.
The viscosity can be measured using a B-type rotational viscometer under the conditions of 25 ° C. and 20 rpm.

The average particle size of the polymer emulsion is preferably 50 to 450 nm.
By using emulsion particles with an average particle size in this range, the basic properties such as heat drying and coating properties required for vibration damping materials will be sufficient, and vibration damping will be even better. It can be. The average particle diameter is more preferably 400 nm or less, still more preferably 350 nm or less, and particularly preferably 200 nm or less. The average particle diameter is more preferably 65 nm or more, still more preferably 100 nm or more, and particularly preferably 150 nm or more. When the average particle diameter of the emulsion particles is within such a range, the operational effects of the resin composition for vibration damping material of the present invention are more effectively exhibited.
The average particle size (volume average particle size) is, for example, after diluting the emulsion with distilled water and thoroughly stirring and mixing, then collecting about 10 ml in a glass cell, and measuring the particle size distribution by a dynamic light scattering method ( It can be determined by measuring with “NICOMP Model 380” manufactured by Particle Sizing Systems.

The polymer emulsion having the above average particle size has a particle size distribution defined by a value obtained by dividing the standard deviation by the volume average particle size (standard deviation / volume average particle size × 100), and exhibits sufficient heat drying properties. From the viewpoint, it is preferably 40% or less. More preferably, it is 30% or less.

It is one of the preferable embodiments of the present invention that the polymer emulsion contained in the resin composition for vibration damping material of the present invention is an emulsion prepared by multistage polymerization.
When the polymer emulsion is an emulsion prepared by multistage polymerization, the polymer obtained in the subsequent polymerization step and the polymer obtained in the immediately preceding polymerization step are completely compatible with each other and have a homogeneous structure in which they cannot be distinguished. It may be a core-shell composite structure or a microdomain structure in which these are not completely compatible but formed inhomogeneously, but among these structures, the characteristics of the emulsion are sufficiently extracted, In order to produce a stable emulsion, a core / shell composite structure is preferable. Especially, it is more preferable that the polymer emulsion is composed of two kinds of polymers, and the two kinds of polymers have a core-shell composite structure in which a core part and a shell part are formed.
An emulsion prepared by multistage polymerization is excellent in vibration damping properties in a wide range within the practical temperature range. Especially in the high temperature range, it exhibits superior vibration damping performance compared to other structure vibration damping material blends. As a result, it exhibits vibration damping performance over a wide range from room temperature to high temperature range within the practical temperature range. can do.
In the emulsion prepared by the multistage polymerization, it is preferable that the polymer obtained in the subsequent polymerization step covers the surface of the polymer obtained in the immediately preceding polymerization step. In this case, it is preferable that the surface of the polymer obtained in the immediately preceding polymerization step is completely covered with the polymer obtained in the subsequent polymerization step, but it may not be completely covered. It may be covered with a mesh or the core may be exposed in some places.

In the present invention, when the polymer emulsion is an emulsion prepared by multistage polymerization, the unsaturated carboxylic (acid) monomer and the other monomer copolymerizable with the unsaturated carboxylic (acid) monomer are: It may be contained in any one of the monomer components used in each polymerization step, and may be contained in two or more or all of them. Moreover, the preferable content rate of each monomer in the monomer component used at each polymerization process is the same as that mentioned above.

When the polymer emulsion is an emulsion prepared by multistage polymerization, the total mass of the monomer components constituting the stage in each stage with respect to the total mass of 100 mass% of the monomer components constituting the polymer emulsion. Is preferably 1 to 99% by mass. Within such a range, the effect of being an emulsion prepared by multistage polymerization can be more fully exhibited. More preferably, it is 5-90 mass%, More preferably, it is 10-80 mass%, More preferably, it is 20-70 mass%, More preferably, it is 30-60 mass%, Most preferably It is 40-50 mass%.

When at least one of the above polymer emulsions is an emulsion prepared by multistage polymerization, the polymer obtained in the subsequent polymerization step and the polymer obtained in the immediately preceding polymerization step are weight average molecular weight, glass transition temperature, SP value. What is necessary is just to be different in any of various physical properties such as (solubility coefficient), the kind of monomer used, and the proportion of the monomer used.

The preferred Tg of the polymer obtained from the total monomer components combined with the monomer components used in each polymerization step of the polymer emulsion produced by the multistage polymerization is the same as the preferred glass transition temperature of the polymer emulsion described above. is there.
The multistage polymerization (emulsion polymerization method) will be described later.

The polymer emulsion is preferably present in an aqueous solvent. When the polymer emulsion is present in an aqueous solvent, the resin composition for vibration damping material of the present invention containing the polymer emulsion is water-based.

When the resin composition for vibration damping material of the present invention is an aqueous one, the same aqueous solvent as used in the production of the polymer emulsion described later can be used as the aqueous solvent.

The polymer emulsion is produced by polymerizing a monomer component by an emulsion polymerization method in the presence of an emulsifier, but the form for carrying out emulsion polymerization is not particularly limited. For example, the monomer component in an aqueous medium The polymerization can be carried out by appropriately adding a polymerization initiator and an emulsifier. Moreover, it is preferable to use a polymerization chain transfer agent or the like for molecular weight adjustment.

When producing the said polymer emulsion by multistage polymerization, it is preferable to obtain using a normal emulsion polymerization method. Specifically, after the monomer component is emulsion-polymerized in an aqueous solvent in the presence of an emulsifier and / or protective colloid to form a core part, the monomer component is further emulsion-polymerized into an emulsion containing the core part. It is preferably obtained by multistage polymerization that forms a shell portion. Thus, the polymer emulsion contained in the resin composition for vibration damping material of the present invention is an emulsion having a core part and a shell part, and the emulsion forms a core part and then a multistage A form obtained by polymerization is also a preferred form of the present invention. The multi-stage polymerization may be one in which after forming the core part and before forming the shell part, the emulsion containing the core part is further emulsion polymerized with a monomer component to form an intermediate part, It is particularly preferable to prepare a polymer emulsion by a two-stage polymerization process in which a shell part is formed immediately after forming a core part. In addition, when performing the process of forming an intermediate part, the said process can be performed 1 process or more. When two or more steps are performed, an intermediate portion composed of a plurality of layers is usually formed.

The aqueous solvent is not particularly limited. For example, water, one or two or more mixed solvents that can be mixed with water, and a mixed solvent in which water is a main component in such a solvent. Etc. Among these, water is preferable in consideration of safety and environmental influence when applying the paint containing the resin composition for vibration damping material of the present invention.

The amount of the emulsifier used is preferably 0.1 to 10 parts by weight, more preferably 0.5 parts per 100 parts by weight of the total amount of compounds having a polymerizable unsaturated bond group as a raw material for the polymer emulsion. -7 parts by weight, more preferably 1-6 parts by weight. Within such a range, the mechanical stability can be sufficiently improved and the polymerization stability can be sufficiently maintained.

As the emulsifier, one or more of anionic (system), cationic (system), nonionic (system), amphoteric surfactants and polymer surfactants can be used.
Examples of the anionic (system), cationic (system), nonionic (system), and amphoteric surfactants are the same as those described in JP2013-199622A.
Examples of commercially available products suitable as the anionic surfactant include Latemul WX, Latemuru 118B, Perex SS-H, Emulgen A-60, B-66, Lebenol WZ (manufactured by Kao Corporation), New Coal 707SF, New Coal 707SN, New Call 714SF, New Call 714SN, AB-26S, ABEX-2010, 2020, 2030, DSB (manufactured by Rhodia Nikka Co., Ltd.) and the like.
In addition, surfactants corresponding to these nonionic types can also be used.

As the above anionic surfactants, reactive surfactants, reactive anionic surfactants, sulfosuccinate type reactive anionic surfactants, alkenyl succinate type reactive anionic surfactants, etc. 1 type (s) or 2 or more types can be used.
Commercially available sulfosuccinate-type reactive anionic surfactants include Latemul S-120, S-120A, S-180 and S-180A (all trade names, manufactured by Kao Corporation), Eleminol JS-2 (Products) Name, manufactured by Sanyo Kasei Kogyo Co., Ltd.), ADEKA rear soap SR-10, SR-20, SR-30 (manufactured by ADEKA) and the like.
As a commercial item of an alkenyl succinate type reactive anionic surfactant, Latemul ASK (trade name, manufactured by Kao Corporation) and the like can be mentioned.
Furthermore, (meth) acrylic acid polyoxyethylene sulfonate salt (for example, “Eleminol RS-30” manufactured by Sanyo Chemical Industries, “Antox MS-60” manufactured by Nippon Emulsifier Co., Ltd.), allyloxymethylalkyloxypolyoxy Sulfate ester (salt) having an allyl group such as sulfonate salt of ethylene (for example, “AQUALON KH-10” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), ammonium polyoxyalkylene alkenyl ether sulfate (for example, “Latemul PD- 104 "etc.) can also be used.

Further, as the anionic surfactant, a reactive surfactant can also be used, and those similar to those described in JP2013-199622A can be used.
Among these surfactants, it is preferable to use a non-nonylphenyl type surfactant from the environmental viewpoint.

As the protective colloid, those described in JP2013-199622A can be used.
The use amount of the protective colloid may be appropriately set according to use conditions and the like, for example, 10 parts by weight or less with respect to 100 parts by weight of the total amount of monomer components used for forming the polymer emulsion. More preferably, it is 5 parts by weight or less, and particularly preferably 3 parts by weight or less. Thus, by using a protective colloid, a polymer emulsion excellent in polymerization stability and mechanical stability can be obtained.

The polymerization initiator is not particularly limited as long as it is a substance that decomposes by heat and generates radical molecules. For example, persulfates such as potassium persulfate, ammonium persulfate, and sodium persulfate; 2,2′-azobis (2-amidinopropane) dihydrochloride, 4,4′-azobis (4-cyanopentanoic acid), 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobisisobutyronitrile Azo compounds such as 2,2′-azobis (2,4-dimethylvaleronitrile); organic peroxidation such as tert-butylperoxy-2-ethylhexanoate, benzoyl peroxide, di-tert-butyl peroxide Products: Hydrogen peroxide and ascorbic acid, t-butyl hydroperoxide and Rongalite, potassium persulfate and metal salts, ammonium persulfate Redox polymerization initiators such as sodium hydrogen sulfite and the like, can be used alone or in combination of two or more thereof.
The amount of the polymerization initiator used is not particularly limited, and may be appropriately set according to the type of the polymerization initiator. For example, the total amount of monomer components used to form the polymer emulsion is 100 parts by weight. On the other hand, it is preferably 0.1 to 2 parts by weight, more preferably 0.2 to 1 part by weight.

In order to accelerate the polymerization, the polymerization initiator may be used in combination with a reducing agent as necessary. As a reducing agent, the thing similar to the thing of Unexamined-Japanese-Patent No. 2013-199622 can be used, and the usage-amount is also the same.

As the polymerization chain transfer agent, the same ones as described in JP2013-199622A can be used.
The amount of the polymerization chain transfer agent used is, for example, preferably 20 parts by weight or less, more preferably 10 parts by weight or less, still more preferably 5.0 parts by weight or less, particularly preferably 100 parts by weight of all monomer components. Is 2.0 parts by weight or less, most preferably 1.0 part by weight or less.

The polymerization may be performed in the presence of a chelating agent such as sodium ethylenediaminetetraacetate, a dispersing agent such as sodium polyacrylate, an inorganic salt, or the like, if necessary. Moreover, as addition methods, such as a monomer component and a polymerization initiator, methods, such as a batch addition method, a continuous addition method, a multistage addition method, are applicable, for example. Moreover, you may combine these addition methods suitably.

Regarding the polymerization conditions in the said manufacturing method, it does not specifically limit as polymerization temperature, For example, 0-100 degreeC is preferable and 40-95 degreeC is more preferable. Also, the polymerization time is not particularly limited, and for example, 1 to 15 hours is preferable, and 5 to 10 hours is more preferable.
The addition method of the monomer component, the polymerization initiator, and the like is not particularly limited, and for example, a batch addition method, a continuous addition method, a multistage addition method, or the like can be applied. Moreover, you may combine these addition methods suitably.

In the method for producing a polymer emulsion by emulsion polymerization, it is preferable to neutralize the emulsion with a neutralizing agent after producing the emulsion by emulsion polymerization. Thereby, the emulsion is stabilized.
The neutralizing agent is not particularly limited, and for example, tertiary amines such as triethanolamine, dimethylethanolamine, diethylethanolamine and morpholine; diglycolamine, aqueous ammonia; sodium hydroxide and the like can be used. These may be used alone or in combination of two or more. Among these, since the water resistance of the coating film formed from the resin composition for vibration damping material is improved, it is preferable to use a volatile base that volatilizes when the coating film is heated. Therefore, it is more preferable to use an amine having a boiling point of 80 to 360 ° C. because vibration damping properties are improved. Examples of such a neutralizing agent include tertiary amines such as triethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, and diglycolamine. Among them, amines having a boiling point of 130 to 280 ° C. are more preferable. . In addition, the said boiling point is a boiling point in a normal pressure. It is also preferable to use aqueous ammonia as a neutralizing agent.

The resin composition for vibration damping material of the present invention contains 10 to 90% by mass of a polymer emulsion, a plasticizer, and a polymer emulsion in a total solid content of 100% by mass of the vinyl lactam polymer in the composition. Is preferred.
The content of the polymer emulsion is more preferably 15% by mass or more, still more preferably 20% by mass or more, still more preferably 25% by mass or more, and particularly preferably 30% by mass or more. The content is more preferably 80% by mass or less, still more preferably 75% by mass or less, still more preferably 70% by mass or less, and particularly preferably 65% by mass or less.

The resin composition for vibration damping material of the present invention may contain other components as long as it contains a polymer emulsion, a plasticizer, and a vinyl lactam polymer. The term “other components” as used herein means the non-volatile content (solid content) remaining in the coating film after the resin composition for vibration damping material is applied and dried by heating. Not included.
As other components, thickeners other than the above-mentioned vinyl lactam monomers are preferable.

Examples of the thickener other than the vinyl lactam monomer include polyvinyl alcohol, cellulose derivatives, polycarboxylic acid resins, and the like. The blending amount of the thickening agent other than the vinyl lactam monomer is 0.01 to 2 in terms of solid content with respect to 100 parts by weight of the total solid content of the polymer emulsion, plasticizer, and vinyl lactam polymer. Part by weight is preferred, 0.05 to 1.5 parts by weight is more preferred, and 0.1 to 1 part by weight is even more preferred. By setting the content of such a thickener, the dispersibility of the pigment and the heat drying property of the coating film are improved, and the vibration damping property can be more sufficiently exhibited without impairing the appearance of the coating film.

The resin composition for vibration damping material of the present invention may further contain a pigment.
As a pigment, 1 type (s) or 2 or more types, such as a coloring agent mentioned later and a rust preventive pigment, can be used, for example. The blending amount of the pigment is preferably 0.1 to 700 parts by weight, more preferably 0.2 to 550 parts by weight based on 100 parts by weight of the total solid content of the polymer emulsion, the plasticizer, and the vinyl lactam polymer. preferable. When the amount of the pigment is such, the dispersibility of the pigment is improved and vibration damping is more fully exhibited.

Other components that can be blended in the vibration damping material resin composition of the present invention include, for example, a foaming agent; an aqueous crosslinking agent; a filler; a gelling agent; a dispersing agent; an antifoaming agent; Antirust pigments; Stabilizers; Wetting agents; Preservatives; Antifoaming agents; Anti-aging agents; Antifungal agents; Ultraviolet absorbers; Antistatic agents, etc. These are used as vibration damping materials. It can be appropriately selected and used according to the form of the resin composition.
In addition, the said other component can be mixed with the said resin composition for vibration damping materials etc. using a butterfly mixer, a planetary mixer, a spiral mixer, a kneader, a dissolver etc., for example.

As the foaming agent, those similar to those described in JP2013-199622A can be used.
As a compounding quantity of the said foaming agent, 0.5-5.0 weight part is preferable with respect to 100 weight part of solid content total of a polymer emulsion, a plasticizer, and a vinyl lactam polymer, and 1.0-4 0.0 part by weight is more preferable. By setting the content of such a foaming agent, the heat drying property of the coating film is improved, and vibration damping properties can be more fully exhibited without impairing the coating film appearance.

As the water-based crosslinking agent, the same ones as described in JP2013-199622A can be used. The blending amount of the water-based cross-linking agent is preferably 0.01 to 20 parts by weight in terms of solid content with respect to 100 parts by weight of the total solid content of the polymer emulsion, plasticizer, and vinyl lactam polymer, for example. -15 parts by weight is more preferable, and 0.5-15 parts by weight is still more preferable. By setting the content of such a water-based cross-linking agent, the heat drying property of the coating film is improved, and vibration damping properties can be more fully exhibited without impairing the coating film appearance.
The water-based cross-linking agent may be added to the polymer emulsion before the plasticizer is added, or may be added simultaneously with the addition of the other components after the plasticizer is added. By mixing a water-based crosslinking agent with the resin composition for vibration damping material, the toughness of the resin is improved, and as a result, sufficient high vibration damping properties are exhibited in a high temperature region. Among them, it is preferable to use an oxazoline compound.

As said filler, the thing similar to the thing of Unexamined-Japanese-Patent No. 2013-199622 other than calcium carbonate can be used.
As a compounding quantity of the said filler, it is preferable to set it as 50-700 weight part with respect to 100 weight part of solid content of a polymer emulsion, a plasticizer, and a vinyl lactam polymer, 100-550 weight part and More preferably.

When a particulate filler is used as the filler, the average particle diameter of the filler is preferably 0.5 to 50 μm, and more preferably 2 to 25 μm. When such a filler is used, the dispersibility of the filler and the heat drying property of the coating film are improved, and vibration damping properties can be more fully exhibited without impairing the appearance of the coating film.
Examples of the particulate filler include calcium carbonate and titanium oxide.
When calcium carbonate is used as the filler, NS # 100, NN # 200, SS # 30 (manufactured by Nitto Flour Chemical Co., Ltd.), R heavy charcoal (manufactured by Maruo Calcium Co., Ltd.) have the preferable average particle diameter as described above. Is preferred.
The average particle size of the filler can be measured by a fully automatic particle size measuring device, and is a value of 50% by weight from the particle size distribution.

Examples of the gelling agent include starch and agar. Among them, starch is preferable.
The blending amount of the gelling agent is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the solid content of the polymer emulsion, plasticizer, and vinyl lactam polymer, and 5 to 50 parts by weight. More preferably.

Examples of the dispersant include inorganic dispersants such as sodium hexametaphosphate and sodium tripolyphosphate, and organic dispersants such as polycarboxylic acid dispersants. Among them, organic dispersants such as polycarboxylic acid dispersants. Is preferred.
The blending amount of the dispersant is preferably 0.1 to 80 parts by weight with respect to 100 parts by weight of the total solid content of the polymer emulsion, the plasticizer, and the vinyl lactam polymer, and is preferably 0.3 to More preferably 8 parts by weight.

Examples of the antifoaming agent include silicon-based antifoaming agents.
Examples of the colorant include organic or inorganic colorants such as titanium oxide, carbon black, dial, hansa yellow, benzine yellow, phthalocyanine blue, and quinacridone red.
Examples of the rust preventive pigment include a metal phosphate, a metal molybdate, and a metal borate.
As the other component, a polyvalent metal compound may be used.

The resin composition for vibration damping material of the present invention preferably has a nonvolatile content (solid content) of 20 to 90% by mass in 100% by mass of the composition. When the non-volatile content is in such a range, the resin composition for vibration damping material tends to form a coating film by coating, and the coating film exhibits excellent vibration damping properties. The non-volatile content is more preferably 30 to 87% by mass, still more preferably 40 to 84% by mass, and particularly preferably 50 to 80% by mass. By setting it as such a ratio of a non-volatile content, heat drying property improves and it becomes possible to exhibit vibration damping property, without impairing a coating-film external appearance.

In addition, when the resin composition for vibration damping material of the present invention is an aqueous composition, the pH of the composition is not particularly limited, but is preferably 4 to 12, more preferably 5 to 11. 6 to 10 is more preferable, and 7 to 9 is particularly preferable. The pH can be adjusted by adding ammonia water, water-soluble amines, alkaline hydroxide aqueous solution and the like to the resin. When such pH is set, the mechanical stability of the resin composition for vibration damping material is improved, and vibration damping properties can be more fully exhibited without impairing the appearance of the coating film during heat drying.
In this specification, pH can be measured with a pH meter. For example, it is preferable to measure the value at 25 ° C. using a pH meter (“F-23” manufactured by Horiba, Ltd.).

The viscosity of the vibration damping material resin composition of the present invention is preferably 50 to 200 Pa · s, more preferably 60 to 150 Pa · s. When the viscosity is such, it is suitable as a resin composition for a coating-type vibration damping material that can be easily applied to a substrate and has no dripping.
The viscosity of the vibration damping material resin composition can be measured by the same method as described above as the method for measuring the viscosity of the polymer emulsion.

This invention is also a vibration damping material obtained using the resin composition for vibration damping materials of this invention.
The vibration damping material of the present invention can be obtained by using the above-described resin composition for vibration damping material of the present invention as a vibration damping material (damping material).
For example, the resin composition for vibration damping material of the present invention is applied to a substrate and dried to form a coating film, which can be used as the vibration damping material of the present invention.
The resin composition for vibration damping material of the present invention is desirably used as a paint, and can be used by applying a resin composition for vibration damping material as a paint to a substrate to form a coating film.

Examples of the method for applying the resin composition for vibration damping material of the present invention to a substrate include a method using a brush, a spatula, an air spray, an airless spray, a mortar gun, a lysine gun and the like.
After applying the resin composition for vibration damping material of the present invention, the condition for drying to form a coating film may be heat drying or room temperature drying, but heat drying from the viewpoint of efficiency. It is preferable. The lower limit of the heat drying temperature is preferably 110 ° C, more preferably 120 ° C. Moreover, 210 degreeC is preferable and the upper limit of the temperature of heat drying has more preferable 170 degreeC. By setting it to such a drying temperature, heat drying property improves and it becomes possible to exhibit vibration damping more fully, without impairing a coating-film external appearance.
The resin composition for vibration damping material of the present invention can also be used as a vibration damping material by preparing a coating film by drying and molding it, and affixing the coating film to a necessary part of the substrate.

The vibration damping property of the vibration damping material of the present invention (hereinafter also referred to as the vibration damping property of the vibration damping material resin composition of the present invention) is evaluated by measuring the loss coefficient of the vibration damping material of the present invention. can do.
The loss factor is usually represented by η and indicates how much the vibration applied to the vibration damping material is attenuated. The loss factor indicates that the higher the numerical value, the better the vibration damping performance.
As a method for measuring the loss factor, a resonance method for measuring near the resonance frequency is generally used, and there are a half width method, an attenuation rate method, and a mechanical impedance method. In the vibration damping material resin composition of the present invention, the loss factor of the film formed from the vibration damping material resin composition is preferably measured by a resonance method using a cantilever method (3 dB method). is there. The measurement using the cantilever method can be performed using, for example, a CF-5200 FFT analyzer manufactured by Ono Sokki Co., Ltd.
Further, the loss factor is obtained by applying the resin composition for vibration damping material on a cold-rolled steel plate (SPCC: width 15 mm × length 250 mm × thickness 1.5 mm) with a coating capacity of 15 mm width × length 250 mm × thickness 3 mm. It is preferable to form a coating film having a surface density of 4.0 kg / m ² on a cold-rolled steel sheet by applying and drying at 150 ° C. for 30 minutes to form a coating film, and measuring using the coating film is preferable. The loss factor is measured by, for example, measuring the loss factor at each temperature of 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. by the resonance method (3 dB method), and each measured numerical value is a smooth curve. And the evaluation is based on the peak value of the curve, and the DPT described above is preferably the peak temperature of the curve. The DPT of the resin composition for vibration damping material of the present invention is preferably 0 ° C. or higher and 100 ° C. or lower. The DPT is more preferably 10 ° C. or higher, and further preferably 20 ° C. or higher. The DPT is more preferably 80 ° C. or less, and further preferably 60 ° C. or less. When the DPT is in such a range, the vibration damping performance in the practical temperature range of the vibration damping material can be expressed more effectively.
Moreover, since the practical temperature range of the film formed from the resin composition for vibration damping material is usually 10 to 60 ° C., the temperatures at 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. The vibration damping performance may be evaluated by a value obtained by summing the loss coefficients, and the films formed from the resin composition for vibration damping material are 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C., respectively. The larger the total loss factor of the total loss factors at temperature, the better the vibration damping performance is exhibited in the practical temperature range of 10 to 60 ° C. of the film formed from the resin composition for vibration damping material. it can.

The resin composition for vibration damping material of the present invention has the above-described configuration, exhibits excellent vibration damping properties in a wide temperature range, has excellent color development properties, and sufficiently slides the coating film when forming a coating film. In particular, it can be suitably used as a coating-type vibration damping material resin composition.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.

<K value>
The K value was measured by the method described above.
<Glass transition temperature>
The measurement of the glass transition temperature was calculated by the calculation formula (1) described above.
<Viscosity>
The viscosity was measured by the method described above.
<Average particle size>
The average particle size was measured by the method described above.
<PH>
The pH was measured by the method described above.

(Production Example 1)
150 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 56.5 parts of methyl methacrylate, 90 parts of styrene, 96 parts of 2-ethylhexyl acrylate, 7.5 parts of acrylic acid, 0.2 part of t-dodecyl mercaptan, Lebenol WZ adjusted to 20% aqueous solution in advance. A first stage monomer emulsion consisting of 45 parts (trade name, manufactured by Kao Corporation) and 48.5 parts deionized water was charged.
Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 4 parts of the above monomer emulsion, 2.5 parts of 5% potassium persulfate aqueous solution and 5 parts of 2% sodium hydrogensulfite aqueous solution were added. The initial polymerization was started. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 120 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 25 parts of a 5% aqueous potassium persulfate solution and 25 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 120 minutes, and the same temperature was maintained for 60 minutes after completion of the addition.
Next, 80 parts of styrene, 17.5 parts of methyl methacrylate, 145 parts of butyl acrylate, 7.5 parts of acrylic acid, 0.2 part of t-dodecyl mercaptan, Lebenol WZ (trade name, A second stage monomer emulsion consisting of 45 parts by Kao Corporation and 48.5 parts deionized water was charged and added dropwise uniformly over 120 minutes. At the same time, 25 parts of a 5% aqueous potassium persulfate solution and 25 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 120 minutes.
After cooling the obtained reaction liquid to room temperature, 5.7 parts of 25% ammonia water was added, non-volatile content 54.5%, pH 7.3, viscosity 700 mPa · s, average particle diameter 190 nm, weight average molecular weight 160,000, An emulsion having a first stage Tg of 10 ° C., a second stage Tg of −10 ° C., and a total Tg of 0 ° C. was obtained. In each production example, the weight average molecular weight was measured by a method of measuring the weight average molecular weight by GPC of a polymer obtained by polymerizing the monomer component.

(Production Example 2)
150 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 70 parts of methyl methacrylate, 25.5 parts of n-butyl acrylate, 100 parts of isobornyl methacrylate, 4.5 parts of acrylic acid, 0.16 part of t-dodecyl mercaptan, LATEMUL PD-104 (product) (First name, manufactured by Kao Corporation, 20% aqueous solution) 36 parts of deionized water and 38.8 parts of deionized water were charged.
Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 4 parts of the above monomer emulsion, 2.5 parts of 5% potassium persulfate aqueous solution and 5 parts of 2% sodium hydrogensulfite aqueous solution were added. The initial polymerization was started. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 120 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 25 parts of a 5% aqueous potassium persulfate solution and 25 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 120 minutes, and the same temperature was maintained for 60 minutes after completion of the addition.
Subsequently, 30 parts of methyl methacrylate, 63 parts of 2-ethylhexyl acrylate, 200.3 parts of isobornyl methacrylate, 6.75 parts of acrylic acid, 0.24 part of t-dodecyl mercaptan, Latemul PD-104 (trade name, A second stage monomer emulsion consisting of 54 parts by Kao Corporation (20% aqueous solution) and 58.2 parts deionized water was charged and added dropwise uniformly over 120 minutes. At the same time, 25 parts of a 5% aqueous potassium persulfate solution and 25 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 120 minutes, and the same temperature was maintained for 90 minutes after completion of the addition to complete the polymerization.
After cooling the obtained reaction liquid to room temperature, 4.3 parts of 25% aqueous ammonia was added, and the nonvolatile content was 54.2%, pH 7.4, viscosity 500 mPa · s, average particle diameter 200 nm, weight average molecular weight 150,000, An emulsion having a first stage Tg of 100 ° C., a second stage Tg of 80 ° C., and a total Tg of 88 ° C. was obtained.

(Production Example 3)
150 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, to the dropping funnel, 277.5 parts of methyl methacrylate, 90 parts of 2-ethylhexyl acrylate, 125 parts of n-butyl acrylate, 7.5 parts of acrylic acid, 2.5 parts of t-dodecyl mercaptan, Latemul PD-104 (product) (Name, Kao Corporation, 20% aqueous solution) 90 parts of monomer and 97 parts of deionized water were charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 4 parts of the above monomer emulsion, 2.5 parts of 5% potassium persulfate aqueous solution and 5 parts of 2% sodium hydrogensulfite aqueous solution were added. The initial polymerization was started. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 240 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 50 parts of a 5% potassium persulfate aqueous solution and 50 parts of a 2% sodium hydrogensulfite aqueous solution were uniformly added dropwise over 240 minutes.
After cooling the obtained reaction liquid to room temperature, 2.8 parts of 25% ammonia water was added, non-volatile content 54.4%, pH 7.3, viscosity 230 mPa · s, average particle diameter 190 nm, weight average molecular weight 80,000, An emulsion having a Tg of 9 ° C. was obtained.

(Production Example 4)
150 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 45.0 parts of methyl methacrylate, 25.0 parts of n-butyl acrylate, 400.0 parts of isobornyl methacrylate, 30.0 parts of acrylic acid, 2.5 parts of t-dodecyl mercaptan, Latemu PD A monomer emulsion consisting of 90 parts of -104 (trade name, manufactured by Kao Corporation, 20% aqueous solution) and 97 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 4 parts of the above monomer emulsion, 2.5 parts of 5% potassium persulfate aqueous solution and 5 parts of 2% sodium hydrogensulfite aqueous solution were added. The initial polymerization was started. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 240 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 50 parts of a 5% potassium persulfate aqueous solution and 50 parts of a 2% sodium hydrogensulfite aqueous solution were uniformly added dropwise over 240 minutes, and the same temperature was maintained for 90 minutes after completion of the dropwise addition to complete the polymerization.
After cooling the obtained reaction liquid to room temperature, 11.3 parts of 25% aqueous ammonia was added, and the nonvolatile content was 54.0%, pH 7.4, viscosity 8500 mPa · s, average particle diameter 180 nm, weight average molecular weight 80,000, An emulsion having a Tg of 144 ° C. was obtained.

(Production Example 5)
150 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 250.0 parts methyl methacrylate, 52.5 parts styrene, 50.0 parts 2-ethylhexyl acrylate, 140.0 parts n-butyl acrylate, 7.5 parts acrylic acid, t-dodecyl mercaptan 2 A monomer emulsion comprising 5 parts, 90 parts of Latemul PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution) and 97 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 4 parts of the above monomer emulsion, 2.5 parts of 5% potassium persulfate aqueous solution and 5 parts of 2% sodium hydrogensulfite aqueous solution were added. The initial polymerization was started. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 240 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 50 parts of a 5% potassium persulfate aqueous solution and 50 parts of a 2% sodium hydrogensulfite aqueous solution were uniformly added dropwise over 240 minutes.
After cooling the obtained reaction liquid to room temperature, 2.8 parts of 25% aqueous ammonia was added, 54.3% nonvolatile content, pH 7.2, viscosity 800 mPa · s, average particle diameter 190 nm, weight average molecular weight 70,000, An emulsion having a Tg of 19 ° C. was obtained.

(Examples 1-4, Comparative Examples 1-3)
As shown in Table 1, plasticizers (1) to (4) and water-soluble polymers I to III were added to the polymers prepared in Production Examples 1 to 5 to prepare mixtures.
In Table 1, the amount of the plasticizer added is shown as a ratio (mass%) with respect to a total of 100 mass% of the nonvolatile content (solid content) of the polymer emulsion and the plasticizer. Moreover, the addition amount of water-soluble polymer was shown by the ratio (mass%) with respect to a total of 100 mass% of polymer emulsion, a plasticizer, and the non volatile matter (solid content) of water-soluble polymer. The nonvolatile content of the obtained mixture of the polymer emulsion, the plasticizer and the water-soluble polymer was adjusted with deionized water so as to be 54% by mass.
Furthermore, the following component was mix | blended with the mixture and the resin composition for vibration damping materials (vibration damping coating material) was obtained.

Mixture of paint blended polymer emulsion, plasticizer and water-soluble polymer 359 parts Calcium carbonate (NN # 200 ^{* 1} ) 620 parts Carbon black 1 part Starch 46.8 parts Dispersant (Aquaric DL-40S ^{* 2} ) 6 parts 4 parts of thickener (Examples 1 and 4 and Comparative Examples 1 to 3 used A as thickener, Example 2 used B, and Example 3 used C.)
A: Acre Reset WR-650 ^{* 3}
B: Primal TT-615 ^{* 4}
C: Primal ASE-95 ^{* 5}
Antifoaming agent (Nopco 8034L ^{* 6} ) 1 part Foaming agent (F-30 ^{* 7} ) 6 parts * 1: Filling material (average particle size 20 μm) manufactured by Nitto Powder Industries
* 2: Nippon Shokubai Co., Ltd. polycarboxylic acid type dispersant (active ingredient 44%)
* 3: Acrylic thickener (30% active ingredient) manufactured by Nippon Shokubai Co., Ltd.
* 4: Acrylic thickener (30% active ingredient) manufactured by Rohm & Haas Co., Ltd.
* 5: Acrylic thickener (30% active ingredient) manufactured by Rohm & Haas Co., Ltd.
* 6: Defoaming agent manufactured by San Nopco Co., Ltd. * 7: Foaming agent manufactured by Matsumoto Yushi Co.

Plasticizer (1): 2,2′-methylenebis (4-ethyl-6-tert-butylphenol) (made by Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK NS-6)
(2): Octylated diphenylamine (Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK AD-F)
(3): N, N-dicyclohexylbenzothiazole-2-sulfenamide (manufactured by Wako Pure Chemical Industries)
(4): Styrenated phenol (Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK SP)

Water-soluble polymer I: Polyvinylpyrrolidone K-30 (trade name, K value of about 30, manufactured by Nippon Shokubai Co., Ltd.)
II: Polyvinylpyrrolidone K-90 (trade name, K value of about 90, manufactured by Nippon Shokubai Co., Ltd.)
III: Polyoxyethylene alkyl ether Emulgen 1150S-60 (trade name, molecular weight 2000 or more, manufactured by Kao Corporation)

<Vibration suppression test>
The obtained resin composition for vibration damping material was applied to a cold-rolled steel plate (SPCC, width 15 mm × length 250 mm × thickness 1.5 mm) at a thickness of 3 mm, dried at 150 ° C. for 30 minutes, and cold-rolled. A coating film having a surface density of 4.0 kg / m ² was formed on the steel plate. The vibration damping property was measured using a cantilever method (loss factor measurement system, manufactured by Ono Sokki Co., Ltd.) at a loss factor η at 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. Was measured by a resonance method (3 dB method). The greater the peak height of the loss factor, the better the damping performance. The total loss coefficient at 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. is preferably 0.45 or more. It can be said that it has.
The half-value width indicates the temperature width of the peak at the portion where the peak top value of the loss coefficient is halved. The peak temperature of the loss factor is also referred to as DPT in this specification. The evaluation results are shown in Table 1. In Table 1, the sum of the loss factors of 10 ° C., 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. is 0.45 or more, and less than 0.45 is x.
The peak height is preferably 0.14 or more. The half width is preferably larger than 25. The peak height x half-value width is preferably 4.5 or more.

<Carbon black coloring, pigment dispersibility>
The appearance of the obtained resin composition for vibration damping material was observed, and pigment dispersibility and coloring of carbon black were evaluated.
◯: Appearance of smooth and smooth carbon black with no pigment fouling ×: Appearance of fouling of pigment or non-uniform coloration of carbon black

<Slip test>
The obtained resin composition for vibration damping material was applied on a cationic electrodeposition coated plate so that the dry film thickness was 3.0 mm, and was kept standing vertically at 60 ° C. using a hot air dryer. The state of the paint after being held for 30 minutes was observed.
○: The paint is in close contact without slipping ×: The paint is sliding 3 mm or more from the initial position

<Mechanical stability>
The obtained resin composition for vibration damping material was stirred with a disper at 3000 rpm × 10 minutes, and the appearance of the composition was evaluated.
○: No change in the composition appearance ×: Aggregates are generated or the viscosity is significantly increased.

As described in Comparative Example 2, in the nonionic surfactant Emulgen 1150S-60 (trade name, polyoxyethylene alkyl ether, manufactured by Kao) as a water-soluble polymer, carbon black coloring, slip test, mechanical stability All were good with polyvinylpyrrolidone. From this result, carbon black coloring, slip test, and mechanical stability are poor with simple water-soluble polymer, but when vinyl lactam polymer having vinylolactam structure is used like polyvinyl pyrrolidone, characteristic performance is exhibited. Thus, it is considered that the present invention can exhibit excellent vibration damping properties in a wide temperature range, improve the color developability of the coating film, and sufficiently prevent the coating film from slipping.
In Comparative Example 2, the mechanical stability was x, but it was possible to produce a vibration damping test sample. However, compared with Comparative Example 2, Comparative Example 3 was worse in mechanical stability and greatly thickened, making it impossible to produce a vibration damping test sample.
Moreover, since the comparative example 1 does not use a plasticizer, it could not exhibit excellent vibration damping performance in a wide temperature range.

Claims (4)

A resin composition for vibration damping material comprising a polymer emulsion,
The composition further comprises a plasticizer and a vinyl lactam polymer, and the resin composition for a vibration damping material. 2. The resin composition for vibration damping material according to claim 1, wherein the polymer emulsion contains a polymer obtained by polymerizing a monomer component containing a (meth) acrylic (acid) monomer. 3. The plasticizer according to claim 1, wherein the plasticizer is at least one selected from the group consisting of aromatic hydrocarbons, heteroaromatic compounds, organic acids, and modified products thereof. A resin composition for vibration damping materials. A vibration damping material obtained using the resin composition for vibration damping material according to claim 1.