WO2014126159A1

WO2014126159A1 - Resin composition for vibration-damping material

Info

Publication number: WO2014126159A1
Application number: PCT/JP2014/053352
Authority: WO
Inventors: 允彦齊藤
Original assignee: 株式会社日本触媒
Priority date: 2013-02-14
Filing date: 2014-02-13
Publication date: 2014-08-21

Abstract

Provided is a resin composition for a vibration-damping material, which can exhibit excellent vibration-damping performance and can be used suitably in use applications in which coating films are required to have a vibration-damping effect. A resin composition for a vibration-damping material, which comprises a polymer produced by polymerizing a monomer component and a plasticizer, said resin composition being characterized by being an aqueous composition in which the polymer exists in the form of an emulsion in an aqueous medium.

Description

Resin composition for vibration damping material

The present invention relates to a resin composition for vibration damping materials. More specifically, vibration damping useful as a material for vibration damping materials used to attenuate vibrations in various structures to prevent mechanical vibration and noise caused by vibrations and maintain stability and quietness. The present invention relates to a resin for a material, a composition for a vibration damping material, and a vibration damping material formed thereby.

In order to attenuate vibrations in various structures to prevent mechanical shaking and noise caused by vibrations and maintain stability and quietness, 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 a material used for such a vibration damping material, conventionally, a molded product such as a plate-shaped molded body or a sheet-shaped molded body made of a material having vibration absorption performance and sound absorption performance has been used. On the other hand, when the shape of the place where vibration or sound is generated is complicated, it is difficult to apply these molded products to the place where vibration is generated. Various methods for exerting the effect have been studied. For example, asphalt sheets containing inorganic powder have been used under the interior floor of automobiles, etc., but since there is a need for heat fusion, improvement in workability and the like is desired. Various compositions for vibration damping materials and polymers to be formed have been studied.

As described above, coating type vibration damping materials (paints) have been developed as substitute materials for molded products, and for example, by coatings formed by spraying or applying an arbitrary method to the corresponding places. Various vibration damping paints that can obtain a vibration damping effect and a sound absorbing effect have been proposed. Specifically, for example, as a water-based vibration damping paint with improved coating film hardness obtained by blending synthetic resin powder with a color developing agent such as asphalt, rubber, synthetic resin, and the like suitable for indoor use in automobiles, Vibration damping coatings in which activated carbon is dispersed as a filler in a resin emulsion have been developed. However, even with these conventional products, it cannot be said that the vibration damping performance is still at a sufficiently satisfactory level, and there is a need for a technique that can further exhibit the vibration damping performance.

As a conventional composition used for a vibration damping material, for example, an emulsion for an aqueous vibration damping material containing at least two kinds of polymers having different glass transition temperatures and specific weight average molecular weights (see Patent Document 1). Is disclosed.

As a resin composition used for such a vibration damping material, it has a hydrogen bond forming ability capable of forming and controlling a hydrogen bond between a resin emulsion having a polar group and the polar group of the resin emulsion. A vibration-damping coating composition containing a specific compound as an aromatic compound having at least one hydroxyl group and further containing an inorganic filler is disclosed (for example, see Patent Document 2). Further, the specific polymer as the base material is composed of one or more selected from a compound having a benzotriazole group that increases the amount of dipole moment in the base material and a compound having a diphenyl acrylate group. An energy conversion composition containing an active ingredient is disclosed (for example, see Patent Document 3). Furthermore, in the vibration-damping paint containing an active ingredient that increases the amount of dipole moment in the paint component in the paint composition, an acrylic polymer substituted with a carboxyl group is disclosed as a coating film component ( For example, see Patent Document 4.) Furthermore, one or two compounds selected from p- (p-toluenesulfonylamido) diphenylamine and octylated diphenylamine in a matrix phase composed of a thermoplastic resin, thermoplastic elastomer, rubber, or water-based emulsion resin An organic damping material having a dispersed phase comprising: the dispersed phase is a dispersed phase in which the compound is microphase-separated in the matrix phase or a completely compatible dispersed phase, and the thermoplastic resin is An organic damping material selected from specific resins is disclosed (for example, see Patent Document 5).

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

As described above, various resin compositions have been disclosed for use in vibration damping material applications. In applications where such resin compositions are used, even better vibration damping properties are exhibited. There is a need for a resin composition, and it has been a challenge to develop a resin composition with improved vibration damping properties that meets such requirements.
In addition, a composition having a form in which dispersion of pigments and the like in the paint is good when used as a paint and a composition having a good appearance after coating are also desired.

The present invention has been made in view of the above situation, and provides a resin composition for a vibration damping material that exhibits excellent vibration damping properties and can be suitably used in applications where a coating film is required to have a vibration damping effect. The purpose is to do.

The inventor has studied various resin compositions for vibration damping materials, and found that a composition obtained by polymerizing a monomer component and further containing a plasticizer exhibits excellent vibration damping performance. . Furthermore, the present inventors have found that the polymer exhibits particularly suitable characteristics by being present in the form of an emulsion in an aqueous solvent, and the present invention has been achieved.

That is, the present invention includes a polymer obtained by polymerizing monomer components, and a plasticizer,
A resin composition for vibration damping material, wherein the polymer is an aqueous composition in the form of an emulsion in an aqueous solvent.
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 obtained by polymerizing monomer components and a plasticizer, and may include at least one of each, and includes two or more. There may be. Moreover, as long as the polymer formed by polymerizing the monomer component and the plasticizer are included, other components may be included.
In the present invention, the plasticizer contained in the vibration damping material resin composition is a component added to improve the vibration damping properties of the vibration damping material resin composition.
By adding a plasticizer, the properties of the resin composition become close to a viscous body, and the vibration damping property (loss coefficient η) is increased.

The polymer obtained by polymerizing the monomer component contained in the resin composition for vibration damping material of the present invention is not particularly limited as long as the effects of the present invention can be exhibited. Selected from the group consisting of acid monomers, unsaturated monomers having nitrogen atoms, unsaturated monomers having aromatic rings, and other monomers copolymerizable with unsaturated carboxylic acid monomers. It is preferable that at least one monomer is included.
In particular, it is preferably obtained from a monomer component containing an unsaturated carboxylic acid monomer. More preferably, it is obtained from a monomer component containing an unsaturated carboxylic acid monomer and another monomer copolymerizable with the unsaturated carboxylic acid 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. However, it preferably contains an ethylenically unsaturated carboxylic acid monomer.
In addition to the unsaturated carboxylic acid monomer, vinyl chloride, ethylene, butadiene, styrene and the like can also be used as the monomer. As the polymer obtained by polymerizing the monomer component, vinyl chloride, polyethylene, polypropylene, polystyrene, styrene-butadiene copolymer and the like can also be used.

The ethylenically 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 One type or two or more types of unsaturated carboxylic acids such as fumarate, monomethyl maleate, monoethyl maleate, or derivatives thereof may be used.
Among these, acrylic acid, methacrylic acid, esters or salts derived from acrylic acid, and esters or salts derived from methacrylic acid are preferred as monomers.
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 A monomer in the form of a COOH group in the form of an ester or salt, or a derivative of such a monomer. The (meth) acrylic monomer includes acrylate and methacrylate.

As a monomer component used as the raw material of the polymer, a (meth) acrylic monomer is preferably contained in an amount of 20% by mass or more based on 100% by mass of all monomer components. More preferably, it is 30 mass% or more. Moreover, it is preferable that a (meth) acrylic-type monomer is 100 mass% or less with respect to 100 mass% of all the monomer components. Such a content ratio of the (meth) acrylic monomer is preferable because of excellent polymerization stability and easy adjustment of Tg.

Among the above (meth) acrylic monomers, examples of the monomer in which the —COOH group is an ester include 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 Dimethacrylate, allyl acrylate, allyl methacrylate, isobornyl acrylate, isobornyl methacrylate, and the like can be mentioned, and it is preferable to use one or more of these.

Among the above (meth) acrylic monomers, in the case of a monomer having a form in which a —COOH group is converted into a salt, the salt is preferably a metal salt, an ammonium salt, an organic amine salt, or the like. Examples of the metal atom forming the metal salt include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; divalent metal atoms such as alkaline earth metal atoms such as calcium and magnesium; aluminum, Trivalent metal atoms such as iron are preferred. Further, as the organic amine salt, an alkanolamine salt such as an ethanolamine salt, a diethanolamine salt, or a triethanolamine salt, or a triethylamine salt is preferable.

In addition, the content ratio of the (meth) acrylic acid monomer in the monomer component used as a raw material for the polymer is 0 to 20% by mass with respect to 100% by mass of the total monomer components from the viewpoint of polymerization stability. It is preferable that the content is 0 to 10% by mass. By including the (meth) acrylic acid-based monomer, when the resin composition for vibration damping material of the present invention includes a filler such as an inorganic filler described later, the dispersibility of the filler is improved and vibration damping is achieved. Will be improved.

The polymer may contain another copolymerizable ethylenically unsaturated monomer as a monomer component, an unsaturated monomer having a nitrogen atom, an unsaturated monomer having an aromatic ring. And other monomers copolymerizable with the unsaturated carboxylic acid monomer.
By including other copolymerizable ethylenically unsaturated monomers, it becomes easy to adjust the acid value, Tg, physical properties and the like of the polymer.
When the resin composition for vibration damping material of the present invention is 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, and ethylvinylbenzene. Styrene is preferred.
That is, the polymer obtained by polymerizing the monomer component is also a styrene (meth) acrylic polymer obtained from a monomer component containing styrene, which is also a preferred embodiment of the present invention. It is.

When the polymer obtained by polymerizing the monomer component is a styrene (meth) acrylic polymer, the monomer component used as a raw material is a styrene monomer with respect to 100% by mass of the monomer component. It is preferable to contain 1 to 90% by mass. More preferably, it is 1 to 80% by mass, and still more preferably 1 to 70% by mass. Further, it is particularly preferably 1 to 50% by mass, particularly preferably 5 to 45% by mass, and 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, Examples thereof include N-methoxyethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, and Ni-butoxymethyl (meth) acrylamide. Acrylonitrile is preferred.
Other monomers that can be copolymerized with the unsaturated carboxylic acid monomer include vinyl formate, vinyl acetate, vinyl propionate, vinyl chloride, ethylene, butadiene, and the like.

The polymer obtained by polymerizing the monomer component is preferably obtained from a monomer component containing a polar group-containing monomer. If the polymer contained in the resin composition for vibration damping material has a polar group, the interaction between the polymer and the plasticizer is increased, and vibration damping is more sufficiently exhibited. Furthermore, when the resin composition for vibration damping material contains two or more polymers, the interaction between these polymers becomes larger, and the friction between the polymers becomes larger. Will be demonstrated.
The content of the polar group-containing monomer is preferably 40 to 100% by mass with respect to 100% by mass of the monomer component. When the content ratio of the polar group-containing monomer is more than 40% by mass, vibration damping is more sufficiently exhibited. More preferred is 45 to 95% by mass, and still more preferred is 50 to 90% by mass. Furthermore, when the resin composition for vibration damping material contains two or more kinds of polymers, vibration damping properties are 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. It is preferable that it is at least one selected from more. More preferably, they are a carboxylic acid ester, a hydroxyl group, and / or a carboxyl group.

The monomer component forming the polymer may further contain an unsaturated monomer having a functional group. Examples of the functional group in the unsaturated monomer having the functional 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, and an alkoxysilane group. Is mentioned. One kind of these functional groups may be present in one molecule of the unsaturated monomer, or two or more kinds thereof may be present. Examples thereof include glycidyl group-containing unsaturated monomers such as glycidyl (meth) acrylate and acrylic glycidyl ether, and these may be used alone or in combination of two or more.
Moreover, the monofunctional unsaturated monomer which has one functional group in 1 molecule may be sufficient, and the polyfunctional unsaturated monomer which has two or more may be sufficient.

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.

When the resin composition for vibration damping material of the present invention contains two or more kinds of polymers obtained by polymerizing monomer components, the two kinds of polymers are used, for example, weight average molecular weight, glass transition temperature, SP value, etc. What is necessary is just to be different in any one of various physical properties such as the kind of monomer to be used and the proportion of the monomer used. Among them, it is preferable that there is a difference in at least one of the weight average molecular weight and the glass transition temperature. When two or more types of polymers having a difference in glass transition temperature are used in the configuration of the resin composition for vibration damping material of the present invention, a wider temperature range than a configuration in which two or more types of polymers are simply added. With this, vibration damping performance can be exhibited. In addition, by appropriately selecting a polymer, it is possible to arbitrarily set a temperature range in which vibration damping performance is exhibited.

The polymer obtained by polymerizing the monomer components preferably has a glass transition temperature of −25 to 180 ° C. When a polymer having such a glass transition temperature is used as the polymer, vibration damping performance in the practical temperature range of the vibration damping material can be effectively expressed. The glass transition temperature of the polymer is more preferably −20 to 150 ° C., still more preferably −20 to 120 ° C. Particularly preferred is -15 to 100 ° C, and most preferred is -10 to 80 ° C.
The glass transition temperature (Tg) of the polymer may be determined based on the knowledge already obtained, or may be controlled by the type and proportion of the monomer component described later, but theoretically It 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 the respective monomers with respect to the total monomer components. Tg ₁ , Tg ₂ ,... Tgn are glass transition temperatures (absolute temperatures) of homopolymers (homopolymers) composed of the respective monomer components.

Further, when the resin composition for vibration damping material of the present invention contains two or more kinds of polymers obtained by polymerizing monomer components, two kinds of polymers having a glass transition temperature difference of 5 to 100 ° C. among them. It is preferable to contain. 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.
By providing a difference in the glass transition temperature (Tg) in this way, for example, when applied to a vibration damping material, it becomes possible to express a higher vibration damping property under a wide temperature range. The vibration damping property in the range of 10 to 60 ° C. is significantly improved. The difference in glass transition temperature (Tg) is more preferably 5 to 90 ° C, and further preferably 5 to 80 ° C. Among them, more preferred is 5 to 60 ° C., particularly preferred is 5 to 50 ° C., and most preferred is 5 to 40 ° C. Moreover, 5 degreeC or more is preferable, as for the minimum of the difference of glass transition temperature (Tg), 10 degreeC or more is more preferable, and 15 degreeC or more is still more preferable.
As will be described later, when the resin composition for vibration damping material of the present invention contains two or more polymers obtained by polymerizing monomer components, the emulsion in which the two or more polymers have a core portion and a shell portion. The case where it exists with this form is also included. In that case, it is preferable that the difference of the glass transition temperature of the polymer which forms a core part and the glass transition temperature of the polymer which forms a shell part exists in the said range.

When the resin composition for vibration damping material of the present invention contains two or more polymers obtained by polymerizing monomer components, at least one of the polymers preferably has a weight average molecular weight of 500 to 1,500,000. By using a material having such a weight average molecular weight, the vibration damping property can be further increased. More preferably, it is 500 to 1,000,000, still more preferably 500 to 500,000, and still more preferably 500 to 300,000. Particularly preferred is 500 to 200,000, and particularly preferred is 1000 to 100,000, and most preferred is 2000 to 50,000. The weight average molecular weight of the polymer obtained by polymerizing the monomer component can be measured by a method using GPC described later.

The resin composition for vibration damping material of the present invention preferably contains 5 to 80% by mass of a polymer obtained by polymerizing monomer components with respect to 100% by mass of the total amount of the resin composition for vibration damping material. . By setting such a polymer content, vibration damping can be further enhanced. More preferably, it contains 10 to 80% by mass. More preferably, it contains 15 to 70% by mass, and particularly preferably 20 to 70% by mass.

The polymer obtained by polymerizing the monomer components preferably has a weight average molecular weight of 10,000 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 of the polymer is more preferably 10,000 to 1,000,000, still more preferably 20,000 to 400,000, particularly preferably 30,000 to 400,000, and most preferably 40,000 to 40,000. It is ten thousand.
In addition, the weight average molecular weight of the polymer formed by polymerizing the monomer component can be determined, for example, 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 obtained by polymerizing the monomer components preferably has a solubility parameter (SP value) 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 the evaporation energy of each monomer component constituting the polymer, and ΣΔe ₁ is a total value of the calculated values of all the monomer components constituting the polymer. ΔV _m is the 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 the molar distribution of each monomer component 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 composition ratio thereof.

The resin composition for vibration damping material of the present invention contains a plasticizer.
Preferable plasticizers include, for example, at least one plasticizer selected from the group consisting of aromatic hydrocarbons, heteroaromatic compounds, organic acids, and modified products thereof.
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 weight average molecular weight of the plasticizer is preferably 100 to 4000. More preferably, it is 120 to 3000, still more preferably 140 to 2000, and particularly preferably 160 to 1000. It is preferable that the weight average molecular weight of the plasticizer is within the above range because of excellent compatibility with the polymer. By setting the weight average molecular weight of the plasticizer within the above range, it is possible to prevent the plasticizer from bleeding out and volatilization at the time of heating and drying, and to further improve the vibration damping property.
The weight average molecular weight of the plasticizer can be determined, for example, 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 SuperHZ1000, TSK-GELSuperMultiporeHZ-M (both manufactured by Tosoh Corporation) are connected in series and used as 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 plasticizer preferably has a polar structure in a ratio of 1 or more to the weight average molecular weight 1000 of the plasticizer. More preferably, it is 1 or more with respect to the weight average molecular weight 900, still more preferably 1 or more with respect to the weight average molecular weight 800, still more preferably 1 or more with respect to the weight average molecular weight 700, Preferably, the number is 1 or more for a weight average molecular weight of 600, and most preferably 1 or more for a weight average molecular weight of 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. , Ethers (including cyclic ethers), thiazoles, triazoles and quinolines. More preferred are an ester group, a hydroxyl group and an amine group, still more preferred are a hydroxyl group and an amine group, and most preferred is a hydroxyl group.
For example, when a plasticizer with a weight average molecular weight of 200 has one amine group per molecule, it will have five polar structures when converted to a weight average molecular weight of 1000.
When the plasticizer has the above-mentioned ratio and the above-mentioned type of polar structure, it becomes easy to obtain a coating film having excellent compatibility with the polymer and no elution of the plasticizer.

A preferred pour point of the plasticizer is -70 to 200 ° C. More preferably, it is −60 to 170 ° C., further preferably −50 to 140 ° C., particularly preferably −40 to 110 ° C., and most preferably −30 to 80 ° C.
When the plasticizer has a pour point in the above range, the compatibility with the polymer is excellent, and the adjustment of the peak temperature (referred to as DPT) of the loss coefficient of the resin composition for vibration damping material of the present invention containing the polymer and the plasticizer is possible. It becomes easy.

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, and styrenated phenols Etc.
In addition, 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 with styrene and 2,4,4-trimethylpentane, 1,3- Guanidines such as diphenylguanidine, N, N'-diphenylguanidine, N, N'-diortolylguanidine, thioureas such as N, N'-diphenylthiourea, α, α'-bis (4-aminophenyl) Anilines such as 1,4-diisopropylbenzene, n-butyraldehyde aniline, ethyl- -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 Benzophenones such as acid, 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- Methylphenol), 2,2'-methylenebis (4-propylphenol), 2, '-Methylenebis (4-chlorophenol), 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), 2,2' -Isobutylidenebis (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 4-benzoyl-3-hydroxyphenoxy) -butane, 1- [2- {3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy} ethyl] -4- {3- (3 5-di-tert-butyl-4-hydroxyphenyl) propionyloxy} -2,2,6,6-tetramethylpiperidine, 1,1,3-tris (5-tert-butyl-4-hydroxy-2-methyl) Phenyl) butane, 2,5-di-tert-butylhydroquinone, 3,9-bis [1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl ] -2,4,8,10-tetraoxaspiro [5.5] undecane, 4-vinylphenol, tetrakis (methylene-di-t-butyl-4-hydrohydrocinnamate), Su- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, pentaerythrityl-tetra [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], Triethylene glycol-bis [3- (3-tert-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, 1,5-dihydroxynaphthalene, 5-amino-1-naphthol, 2-amino-6-hydroxynaphthol, etc. Examples include naphthols.

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-sulfen 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-tert-butyl-5- (5-chloro-2H-) Nzotriazol-2-yl) -4-hydroxyphenyl] 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 adipate esters such as 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 fats and 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-tert-butylphenyl) pentaerythritol diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl-4-hydroxy-5-tert-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-nonylpheno Shi) 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 molecules obtained by using phenols and styrenes as reaction raw materials.
Examples of phenols include polyhydric phenols such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, 1,4-dihydroxybenzene, 1,2,3-trihydroxybenzene, and the like in addition to phenol (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 styrene is preferable.

As the styrenated phenol obtained by reacting these phenols with styrene, mono (or di, tri) (α-methylbenzyl) phenol obtained by reacting phenol with styrene is preferable.
When the styrenated phenol is mono (or di, tri) (α-methylbenzyl) phenol, one of mono-α-methylbenzylphenol, di-α-methylbenzylphenol and 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.

The plasticizer content in the vibration damping material resin composition of the present invention is 10 to 2000 parts by weight with respect to 100 parts by weight of the polymer obtained by polymerizing the monomer component in the vibration damping material resin composition. It is preferable. By including the plasticizer at such a ratio, the resin composition for vibration damping material exhibits more excellent vibration damping properties. More preferably, it comprises 10 to 1000 parts by weight of a plasticizer, more preferably 10 to 500 parts by weight, per 100 parts by weight of a polymer obtained by polymerizing monomer components. . Further, it is particularly preferred that it comprises 10 to 200 parts by weight, particularly preferred that it comprises 15 to 180 parts by weight, and most preferred that it comprises 20 to 160 parts by weight.

The resin composition for vibration damping material of the present invention is an aqueous composition in which a polymer obtained by polymerizing a monomer component is present in the form of an emulsion in an aqueous solvent.
The plasticizer and the polymer thickener described below may be included in the polymer, or the plasticizer and the polymer thickener described below are present in the form of an emulsion in the aqueous solvent. However, it is particularly preferred that the thickener is in a state dissolved in the aqueous phase of the emulsion.

In the present invention, the viscosity of the polymer emulsion is not particularly limited, but is preferably 10 to 10000 mPa · s, more preferably 15 to 8000 mPa · s, and still more preferably 20 to 6000 mPa · s. By using an emulsion having such a viscosity, the dispersibility of the pigment is improved, and vibration damping properties 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.

In the present invention, the viscosity of the vibration damping material resin composition is not particularly limited. However, when the vibration damping material resin composition includes a polymer, a plasticizer, and a polymer thickener, the polymer thickener is further increased. It is determined as the viscosity measured using a B-type rotational viscometer in the state where the adhesive is mixed.
Using a B-type rotational viscometer, the viscosity measured under conditions of 25 ° C. and 20 rpm (hereinafter referred to as high shear viscosity (η2)) and the viscosity measured under conditions of 25 ° C. and 2 rpm (hereinafter referred to as low shear viscosity (hereinafter referred to as “low shear viscosity”) The ratio (= η1 / η2) between the low shear viscosity (η1) and the high shear viscosity (η2) obtained by measuring η1)) is called a TI value, and the TI value is preferably 1 or more and 9 or less.
A more preferred lower limit of the TI value is 2, and a more preferred lower limit is 3.
Further, a more preferable upper limit value of the TI value is 8, and a more preferable upper limit value is 7.
In addition, the viscosity of a composition containing a polymer obtained by polymerizing monomer components and a plasticizer that does not contain a polymer thickener is 10 to 10,000 mPa · s measured at 25 ° C. and 20 rpm. It is preferably 15 to 8000 mPa · s, more preferably 20 to 6000 mPa · s.
By using the resin composition for vibration damping material having such a viscosity, the dispersibility of the pigment is improved, and the vibration damping property can be more fully exhibited.

The resin composition for vibration damping material of the present invention preferably has a nonvolatile content in the composition of 20 to 90% by mass with respect to 100 parts by weight of the entire resin composition for vibration damping material. When the non-volatile content is in such a range, the resin composition for vibration damping material can easily form a coating film by coating, and the coating film exhibits more excellent vibration damping properties. The non-volatile content in the composition is more preferably 30 to 87% by mass, and still more preferably 40 to 84% by mass.
In addition, the non-volatile content here means components other than the aqueous solvent contained in an emulsion.

The average particle diameter of the emulsion particles in the vibration damping material resin composition of the present invention is preferably 50 to 450 nm.
By using emulsion particles with an average particle diameter in this range, the basic properties such as heat drying properties and coating properties required for vibration damping materials will be sufficient, and vibration damping properties will be even better. Can be. The upper limit is more preferably 400 nm or less, still more preferably 350 nm or less. The lower limit is particularly preferably 100 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. Moreover, the lower limit of the average particle diameter is preferably 65 nm or more, more preferably 80 nm or more.
The average particle size (volume average particle size) can be determined by, for example, diluting the emulsion with distilled water, thoroughly stirring and mixing, then collecting about 10 ml in a glass cell, and measuring the particle size distribution analyzer (Particle) by the dynamic light scattering method. It can be determined by measuring with “NICOMP Model 380” manufactured by Sizing Systems.

The emulsion particles having the above average particle diameter preferably have a particle size distribution defined by a value obtained by dividing the standard deviation by the volume average particle diameter (standard deviation / volume average particle diameter × 100) of 40% or less. More preferably, it is 30% or less. When the particle size distribution is set within such a range, the resin composition for vibration damping material can exhibit sufficient heat drying properties.

The pH of the resin composition for vibration damping material of the present invention is not particularly limited, but is preferably 4 to 12, more preferably 5 to 11, and still more preferably 6 to 10. The pH of the vibration damping material resin composition can be adjusted by adding ammonia water, water-soluble amines, alkaline hydroxide aqueous solution, or 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.).

In the present invention, the polymer obtained by polymerizing the monomer component may be one kind of polymer as described above, or may be composed of two or more kinds of polymers. Further, the polymer may be composed of two or more kinds of polymers, and may be in a form in which they are combined, but two or more kinds of polymers exist in the form of an emulsion having a core part and a shell part, so-called A core-shell structure is preferred.
An emulsion having a core-shell composite structure is excellent in vibration damping properties in a wide range within a practical temperature range. Especially in the high temperature range, it exhibits superior vibration damping properties compared to other forms of vibration damping material blends. As a result, vibration damping performance over a wide range from room temperature to high temperature within the practical temperature range. Can be demonstrated.
In the core-shell structure, it is preferable that the surface of the core part is covered with the shell part. In this case, it is preferable that the surface of the core part is completely covered with the shell part, but it may not be completely covered. For example, the core part may be covered in a mesh shape or in some places. The part may be exposed.
The emulsion particles having the core part and the shell part can be obtained by using an emulsion polymerization method (multistage polymerization) described later.

Moreover, it is preferable that at least 1 type in the polymer which forms a polymer emulsion is a form of the emulsion particle which has a core part and a shell part. Thereby, the interface between polymers can be increased and effects, such as a vibration damping improvement, can be enlarged more.

In the present invention, when the polymer obtained by polymerizing the monomer component has a core part and a shell part, an ethylenically unsaturated carboxylic acid monomer and an ethylenically unsaturated carboxylic acid monomer The other copolymerizable monomer may be contained in either the monomer component that forms the core part of the emulsion or the monomer component that forms the shell part, and is used for both of these. There may be. Moreover, the preferable content rate of each monomer in the monomer component which forms a core part, and the preferable content rate of each monomer in the monomer component which forms a shell part are the same as what was mentioned above. It is.

In the present invention, when the polymer obtained by polymerizing the monomer component is in a form having a core part and a shell part, the total mass of the monomer components constituting the core part and the monomer constituting the shell part The mass ratio (core part / shell part) to the total mass of the components is preferably 30/70 to 70/30. Within such a range, the effect of the core / shell composite structure can be more fully exhibited. More preferably, it is 35/65 to 65/35.

When at least one of the polymers contained in the resin composition for vibration damping material of the present invention is in the form of emulsion particles having a core part and a shell part, the polymer and shell part obtained from the monomer component forming the core part The polymer obtained from the monomer component that forms the weight average molecular weight, the glass transition temperature, the SP value (solubility coefficient), the type of monomer used, the usage ratio of the monomer, etc. Any one of them may be different, but among them, it is preferable that there is a difference in at least one of the weight average molecular weight and the glass transition temperature.
The difference in glass transition temperature (Tg) between the polymer obtained from the monomer component forming the core part and the polymer obtained from the monomer component forming the shell part is the glass in the case of containing two or more kinds of the above-mentioned polymers. The same as the difference in transition temperature is preferred.
The Tg of the polymer obtained from the total monomer component including the monomer component forming the core portion and the monomer component forming the shell portion is preferably −25 to 180 ° C. . More preferably, it is −20 to 150 ° C., and further preferably −20 to 120 ° C. Among them, it is more preferably −20 to 100 ° C., particularly preferably −15 to 100 ° C., particularly preferably −10 to 100 ° C., and most preferably −10 to 80 ° C.
The emulsion particles having the core part and the shell part can be obtained by using an emulsion polymerization method (multistage polymerization) described later.

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

The resin composition for vibration damping material of the present invention preferably includes a polymer thickener.
It is preferable that the composition used for the paint application has good dispersion of pigments in the paint, and the appearance after application is good without sagging the paint after application. When the resin composition for vibration damping material contains a polymer thickener, pigment dispersibility is improved when used as a paint, and sagging during application is suppressed. In addition, the coating film obtained from the resin composition for vibration damping material of the present invention by containing a polymer thickener has no impact, high impact resistance, and excellent flexibility. Even if it bends, it becomes difficult to crack. Moreover, the effect that it becomes a thin film after drying is also acquired.
Examples of preferred polymeric thickener structures include polyvinyl alcohol thickeners, polyvinylpyrrolidone thickeners, unsaturated carboxylic acid (co) polymer thickeners, cellulose derivative thickeners, and poly An ether urethane modified material thickener is mentioned.

Examples of the classification of the polymeric thickener of the present invention include thixotropy imparting type thickeners and Newtonian fluidity imparting type thickeners.
Here, the thixotropy imparting thickener in the present invention is a thickener that improves the viscosity of a liquid and has a function of imparting thixotropy (thixotropic property). On the other hand, a Newtonian fluidity-providing thickener is a thickener that has the properties of a non-Newtonian liquid such as an emulsion close to Newtonian viscosity, that is, a function that imparts Newtonian fluidity to a non-Newtonian liquid. Say.
Among these, as the polymer thickener of the present invention, a thixotropic imparting thickener is more preferable.
The thixotropy imparting thickener has a strong effect of increasing the low shear viscosity (η1), and has a weaker effect of increasing the high shear viscosity (η2). This characteristic can be said to be a characteristic suitable as a polymer thickener used in the present invention.

Specific examples of thixotropy imparting thickeners include unsaturated carboxylic acid (co) polymer thickeners such as Primal (registered trademark) ASE-60, Primal TT-615 (Rohm & Haas), Zogen (registered) Trademark) 100, Zogen 150, Zogen 200, Zogen 250, Zogen 350 (Daiichi Kogyo Seiyaku Co., Ltd.), RHEOLATE1, RHEOLATE101, RHEOLATE430 (RHEOX), SN Thickener A-815, SN Thickner A-818 (Sannopco) ), RHEOVIS CR (manufactured by Yushi Kogyo Co., Ltd.), Aron B-300K, Aron A-7070 (manufactured by Toagosei Co., Ltd.), Chikuzol K-150B (manufactured by Kyoeisha Yushi Chemical Co., Ltd.) ), Acre Reset (registered trademark) WR-503A, Acre Reset WR- 07, Acriset WR-650 (manufactured by Nippon Shokubai Co., Ltd.), polyether urethane modified thickeners such as Adecanol (registered trademark) UH-462, Adecanol UH-752 (Asahi Denka Kogyo Co., Ltd.), RHEOLATE266 and RHEOLATE288 (RHEOX) are listed. One or more of these can be used as a thixotropy imparting thickener.

Specific examples of Newtonian fluidity-providing thickeners include unsaturated carboxylic acid (co) polymer thickeners such as Primal ASE-75, Primal ASE-95, Primal ASE-108, Primal RM-5 (Rohm & Haas) SN thickener A-850 (manufactured by San Nopco), polyether polyol type thickeners such as RHEOLATE300, RHEOLATE310, RHEOLATE350 (RHEOX), SN thickener A-801, SN thickener A-806, SN thickener A-816 (manufactured by Sannopco), Tixol T-210, Tixol T-212 (manufactured by Kyoeisha Oil Chemical Co., Ltd.), polyether urethane modified thickeners such as Adecanol UH-140S, Adecanol UH-420, Adecanol U -438, Adecanol UH-472, Adecanol UH-450, Adecanol UH-540, Adecanol UH-550, Adecanol UH-541, Adecanol UH-526, Adecanol UH-530 (Asahi Denka Kogyo Co., Ltd.), RHEOLATE 244, RHEOLATE25 , RHEOLATE 278 (manufactured by RHEOX), SN thickener A-803, SN thickener A-804, SN thickener A-807, SN thickener A-812, SN thickener A-814 (manufactured by San Nopco). Specific examples of Newtonian fluidity-providing thickeners other than those mentioned above can further include DK thickener SCT-200 and DK thickener SCT-270 (Daiichi Kogyo Seiyaku Co., Ltd.). One or more of these can be used as a Newtonian fluidity-providing thickener.

Examples of the polyvinyl alcohol thickener include PVA-105, PVA-CST, PVA-217, and PVA-420H (manufactured by Kuraray Co., Ltd.).
Examples of the polyvinyl pyrrolidone thickener include polyvinyl pyrrolidone K-30, K-85, K-90 (manufactured by Nippon Shokubai Co., Ltd.) and the like.
Examples of the unsaturated carboxylic acid (co) polymer thickener include the thickeners listed as specific examples of the thixotropy imparting thickener or the Newton fluidity imparting thickener.
Examples of the cellulose derivative-based thickener include CMC Daicel 2200, 2260, 2280, 2450 (manufactured by Daicel Finechem Co., Ltd.), Poise C-60H, C-150L (manufactured by Kao Corporation), and the like.
Examples of the polyether urethane-modified thickener include the thickeners listed as specific examples of the thixotropy imparting thickener or the Newton fluidity imparting thickener.
Among these, unsaturated carboxylic acid (co) polymer thickeners are more preferable, and alkali-soluble unsaturated carboxylic acid (co) polymer thickeners are more preferable.
Unsaturated carboxylic acid (co) polymer thickeners are preferred because they have excellent affinity with polymers when used in combination with polymers obtained by polymerizing saturated carboxylic acid monomers.

The amount of the polymeric thickener added is preferably 0.1 parts by weight or more, more preferably 0.2 parts by weight, in terms of solid content with respect to 100 parts by weight of the solid content of the polymer obtained by polymerizing the monomer component. More preferably, it is 0.25 parts by weight or more, preferably 10 parts by weight or less, more preferably 5 parts by weight or less, and still more preferably 2 parts by weight or less.

The weight average molecular weight of the polymeric thickener is preferably 300,000 or more, more preferably 500,000 or more, still more preferably 700,000 or more, and most preferably 1,000,000 or more.
The weight average molecular weight of the polymeric thickener can be measured by the method using GPC as described above.

The loss tangent (tan δ) peak temperature (TPT) of the resin composition for vibration damping material of the present invention is preferably 0 ° C. or higher and 100 ° C. or lower.
The TPT of the resin composition for vibration damping material of the present invention is measured in a state where the polymer and plasticizer included in the resin composition for vibration damping material are mixed with the polymer thickener when the polymer thickener is further included. The peak temperature of the loss tangent (tan δ) in the dynamic viscoelasticity measurement.
The TPT of the vibration damping material resin composition is preferably 0 ° C. or higher, more preferably 10 ° C. or higher, and further preferably 20 ° C. or higher.
Moreover, it is preferable that TPT of the resin composition for vibration damping materials is 100 ° C. or less, more preferably 80 ° C. or less, and further preferably 60 ° C. or less.
When the TPT of the resin composition for vibration damping material of the present invention is in such a range, it is preferable because it is easy to adjust the DPT of the resin composition for vibration damping material to a practical temperature range.
As a method for measuring the loss tangent, a method for determining the loss tangent tan δ by dynamic viscoelasticity measurement can be used. The dynamic viscoelasticity measurement can be performed using, for example, a rheometer (RSAIII, manufactured by TA Instruments, or ARES, manufactured by TA Instruments).
The loss tangent peak temperature was as follows. The resin composition for vibration damping material was applied on a Teflon (registered trademark) plate with a smooth surface so that the film thickness after drying was 0.2 mm, and dried at 90 ° C. for 30 minutes. It can be measured with a sample which is dried under reduced pressure at 100 ° C. for 30 minutes and cut into a size of 25 mm long × 5 mm wide.
Alternatively, the resin composition for vibration damping material is applied on a Teflon (registered trademark) plate having a smooth surface so that the film thickness after drying is 0.5 mm, dried at 90 ° C. for 30 minutes, and then at 100 ° C. for 30 minutes. It can carry out by the measuring method by a shear mode using the sample dried under reduced pressure and cut out to the size of 25 mm in diameter.

The resin composition for vibration damping material of the present invention contains a polymer obtained by polymerizing monomer components and a plasticizer, and further contains other components as long as it contains a polymer thickener as necessary. May be included.
When other components are included, the proportion of the other components is preferably 10% by mass or less, and more preferably 5% by mass or less, with respect to the entire resin composition for vibration damping material. The term “other components” as used herein refers to the non-volatile content (solid content) remaining in the coating film even after the resin composition for vibration damping material is applied and dried by heating. Not included.
In the vibration damping material resin composition of the present invention, the solid content is preferably 40 to 90% by mass, more preferably 50 to 80% by mass, based on the entire vibration damping material resin composition. . By making the content of such a solid content, the heat drying property is improved, and the vibration damping property can be more fully exhibited without impairing the appearance of the coating film.

In the method for producing a vibration damping material resin composition of the present invention, the polymer contained in the vibration damping material resin of the present invention is produced by polymerizing a monomer component by an emulsion polymerization method in the presence of an emulsifier. be able to.
The form for carrying out the emulsion polymerization is not particularly limited. For example, the emulsion polymerization can be carried out by suitably adding a monomer component, a polymerization initiator and an emulsifier to an aqueous solvent for polymerization. Moreover, it is preferable to use a polymerization chain transfer agent or the like for molecular weight adjustment.

When the emulsion is an emulsion having a core part and a shell part, it is preferably obtained by using a usual 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, a form in which the polymer emulsion is an emulsion having a core part and a shell part, and the emulsion is obtained by multistage polymerization that forms a shell part after the core part is formed, is also of the present invention. One preferred form.

The amount of the emulsifier used is preferably 0.1 to 10% by mass with respect to 100% by mass of the total amount of compounds having a polymerizable unsaturated bond group. More preferably, it is 0.5-7% by mass, and still more preferably 1-6% by mass. If the amount used is set 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.
The anionic surfactant is not particularly limited, and examples thereof include polyoxyalkylene alkyl ether sulfate, polyoxyalkylene oleyl ether sulfate sodium salt, polyoxyalkylene alkylphenyl ether sulfate, alkyl diphenyl ether disulfonate, poly Oxyalkylene (mono, di, tri) styryl phenyl ether sulfate, polyoxyalkylene (mono, di, tri) benzyl phenyl ether sulfate, alkenyl succinate; sodium dodecyl sulfate, potassium dodecyl sulfate, ammonium alkyl sulfate Alkyl sulfate salts such as sodium dodecyl polyglycol ether sulfate; sodium sulforicinoate; Alkyl sulfonates such as sodium salts; alkyl sulfonates such as sodium dodecylbenzene sulfonate and alkali metal sulfates of alkali phenol hydroxyethylene; high alkyl naphthalene sulfonates; naphthalene sulfonic acid formalin condensates; sodium laurate, triethanolamine oleate, tri Fatty acid salts such as ethanolamine abietate; polyoxyalkyl ether sulfate ester; polyoxyethylene carboxylic ester sulfate salt; polyoxyethylene phenyl ether sulfate ester; succinic acid dialkyl ester sulfonate salt; polyoxyethylene alkyl aryl sulfate Examples include salts. These 1 type (s) or 2 or more types can be used.

Commercially available products suitable as the anionic surfactant include, for example, Latemul WX, Latemul 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.
Commercial products of 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 (Product) 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 salts (for example, “Eleminol RS-30” manufactured by Sanyo Kasei Kogyo Co., Ltd., “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-” manufactured by Kao Corporation 104 "etc.) can also be used.

Further, as the anionic surfactant, the following surfactants and the like can be used as the reactive surfactant.
Sulfoalkyl (carbon number 1 to 4) ester salt type surfactant of aliphatic unsaturated carboxylic acid having 3 to 5 carbon atoms, such as 2-sulfoethyl (meth) acrylate sodium salt, 3-sulfopropyl (meth) acrylate ammonium (Meth) acrylic acid sulfoalkyl ester salt type surfactants such as salts; sulfopropylmaleic acid alkylester sodium salt, sulfopropylmaleic acid polyoxyethylene alkylester ammonium salt, sulfoethylfumaric acid polyoxyethylene alkylester ammonium salt, etc. Aliphatic unsaturated dicarboxylic acid alkyl sulfoalkyl diester salt surfactants.

The nonionic surfactant is not particularly limited. For example, polyoxyethylene alkyl ether; polyoxyethylene alkyl aryl ether; sorbitan aliphatic ester; polyoxyethylene sorbitan aliphatic ester; aliphatic such as monolaurate of glycerol Monoglyceride; polyoxyethyleneoxypropylene copolymer; condensation products of ethylene oxide and aliphatic amines, amides or acids. Further, allyloxymethylalkoxyethylhydroxypolyoxyethylene (for example, “ADEKA rear soap ER-20” manufactured by ADEKA), polyoxyalkylene alkenyl ether (for example, “Latemul PD-420”, “Latemul PD-” manufactured by Kao Corporation Nonionic surfactants having reactivity such as “430” and the like can also be used. These 1 type (s) or 2 or more types can be used.

The cationic surfactant is not particularly limited, and examples thereof include dialkyldimethylammonium salts, ester-type dialkylammonium salts, amide-type dialkylammonium salts, dialkylimidazolinium salts, and the like. Can be used.

The amphoteric surfactant is not particularly limited, and examples thereof include alkyldimethylaminoacetic acid betaine, alkyldimethylamine oxide, alkylcarboxymethylhydroxyethylimidazolinium betaine, alkylamidopropylbetaine, alkylhydroxysulfobetaine, and the like. 1 type (s) or 2 or more types can be used.

The polymer surfactant is not particularly limited. For example, polyvinyl alcohol and a modified product thereof; (meth) acrylic water-soluble polymer; hydroxyethyl (meth) acrylic water-soluble polymer; hydroxypropyl (meth) acrylic Water-soluble polymers such as polyvinyl pyrrolidone, and one or more of them can be used.
Among the above surfactants, it is preferable to use a non-nonylphenyl type surfactant from the environmental viewpoint.

Examples of the protective colloid include polyvinyl alcohols such as partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, and modified polyvinyl alcohol; cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and carboxymethyl cellulose salt; natural polysaccharides such as guar gum Etc., and one or more of these can be used. The protective colloid may be used alone or in combination with a surfactant.
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 to form the polymer. 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, an emulsion having excellent 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 peroxides 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 set as appropriate according to the type of the polymerization initiator. For example, the total amount of monomer components used to form the polymer is 100 parts by weight. The amount 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. Examples of the reducing agent include reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, and glucose; for example, reducing inorganic compounds such as sodium thiosulfate, sodium sulfite, sodium bisulfite, and sodium metabisulfite. These 1 type (s) or 2 or more types can be used.
The amount of the reducing agent used is not particularly limited. For example, it is preferably 0.05 to 1 part by weight with respect to 100 parts by weight of the total amount of monomer components used to form the polymer.

The polymerization chain transfer agent is not particularly limited, and examples thereof include alkyl mercaptans such as hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, and n-tetradecyl mercaptan; carbon tetrachloride , Halogenated hydrocarbons such as carbon tetrabromide and ethylene bromide; mercaptocarboxylic acid alkyl esters such as mercaptoacetic acid 2-ethylhexyl ester, mercaptopropionic acid 2-ethylhexyl ester, mercaptopyropionic acid tridecyl ester; mercaptoacetic acid methoxybutyl Mercaptocarboxylic acid alkoxyalkyl ester such as ester, mercaptopropionic acid methoxybutyl ester; carboxylic acid mercaptoal such as octanoic acid 2-mercaptoethyl ester Glycol ester or, alpha-methylstyrene dimer, terpinolene, alpha-terpinene, .gamma.-terpinene, dipentene, anisole, allyl alcohol and the like. These may be used alone or in combination of two or more. Of these, alkyl mercaptans such as hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan are preferably 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, with respect to 100 parts by weight of all monomer components. More preferably, it is 5.0 parts by weight or less, particularly preferably 2.0 parts by weight or less, and 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 above production method, the polymerization temperature is not particularly limited, and for example, it is preferably 0 to 100 ° C., more preferably 40 to 95 ° C. Also, the polymerization time is not particularly limited, and for example, it is preferably 1 to 15 hours, more preferably 5 to 10 hours.
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 contained in the vibration damping material resin composition of the present invention, it is preferable to produce an emulsion by emulsion polymerization and then neutralize the emulsion with a neutralizing agent. As a result, 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 materials is improved, it is preferable to use a volatile base that volatilizes when the coating film is heated. More preferably, an amine having a boiling point of 80 to 360 ° C. is preferably used because heat drying properties are improved and vibration damping properties are improved. As such a neutralizing agent, for example, tertiary amines such as triethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, and diglycolamine are preferable. More preferably, an amine having a boiling point of 130 to 280 ° C. is used.
In addition, the said boiling point is a boiling point in a normal pressure.
The molecular weight of the neutralizing agent is not particularly limited, but is preferably 130 to 280 from the viewpoint of volatility.
Further, it is preferable to add the amine in an amount of 0.6 to 1.4 equivalents with respect to 1 equivalent of the acid group contained in the polymer emulsion. More preferably, it is 0.8 to 1.2 equivalents.

The resin composition for vibration damping material of the present invention can contain other components as necessary. The vibration damping material resin composition further comprising a pigment is one of the preferred embodiments of the present invention, and in particular, the vibration damping material further comprises a pigment and a thickener. The resin composition for use is also a preferred embodiment of the present invention. As the thickener, the above-described polymer thickener is preferable.
Such a resin composition for vibration damping material of the present invention has excellent heat drying properties, can exhibit various functions, and forms a vibration damping material that can exhibit particularly excellent vibration damping properties. It is something that can be done.

When the vibration damping material resin composition includes a pigment and a thickener, the solid content is preferably 20 to 90% by mass with respect to 100% by mass of the total amount of the vibration damping material resin composition. The amount is preferably 30 to 90% by mass, and more preferably 40 to 90% by mass. By making the content of such a solid content, the heat drying property is improved, and the vibration damping property can be more fully exhibited without impairing the appearance of the coating film.
As the blending amount of the polymer obtained by polymerizing the monomer component in the vibration damping material resin composition containing the pigment and the thickener, for example, with respect to 100% by mass of the solid content of the vibration damping material resin composition, The solid content of the polymer obtained by polymerizing the monomer components is preferably set to 10 to 60% by mass, more preferably 15 to 60% by mass. By setting the blending amount of such a polymer, vibration damping is more fully exhibited.

When the vibration damping material resin composition contains a pigment and a thickener, the pH of the vibration damping material resin composition is preferably 7 to 11, more preferably 7 to 9. The pH can be measured by the same method as described above. At such a pH, the performance of the thickener is sufficiently exhibited, and the pigment dispersibility is improved, so that the vibration damping property is more sufficiently exhibited.
When the vibration damping material resin composition includes a pigment and a thickener, the viscosity of the vibration damping material resin composition is preferably 50 to 200 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. More preferably, it is 60 to 150 Pa · s.
The viscosity of the vibration damping material resin composition can be measured by the same method as described above.

As said pigment, 1 type (s) or 2 or more types, such as the coloring agent mentioned later and a rust preventive pigment, can be used, for example. The pigment content is preferably 50 to 700 parts by weight, more preferably 100 parts by weight of the solid content of the polymer obtained by polymerizing the monomer component in the resin composition for vibration damping material. 100 to 550 parts by weight. 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; a solvent; an aqueous cross-linking agent; a filler; a gelling agent; a dispersing agent; Anticorrosive pigments, stabilizers, wetting agents, preservatives, antifoaming agents, anti-aging agents, antifungal agents, ultraviolet absorbers, antistatic agents, etc., and one or more of these may be vibrationally attenuated It can be suitably selected and used according to the form of the resin composition for materials.
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, for example, a low-boiling hydrocarbon encapsulated heated expansion capsule, an organic foaming agent, an inorganic foaming agent, and the like are suitable, and one or more of these can be used. Examples of the heat-expandable capsule include Matsumoto Microsphere F-30, F-50 (manufactured by Matsumoto Yushi Co., Ltd.); EXPANSELL WU642, WU551, WU461, DU551, DU401 (manufactured by Nippon Expandcel). Examples of the organic blowing agent include azodicarbonamide, azobisisobutyronitrile, N, N-dinitrosopentamethylenetetramine, p-toluenesulfonylhydrazine, p-oxybis (benzenesulfohydrazide), and the like. Examples of the foaming agent include sodium bicarbonate, ammonium carbonate, silicon hydride and the like.
The blending amount of the foaming agent is 0.5 to 5.0 parts by weight with respect to 100 parts by weight of the solid content of the polymer obtained by polymerizing the monomer component in the vibration damping material resin composition. The amount is preferably 1.0 to 3.0 parts by weight. 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.

Examples of the solvent include ethylene glycol, butyl cellosolve, butyl carbitol, butyl carbitol acetate, and the like. What is necessary is just to set suitably as a compounding quantity of a solvent so that the solid content concentration of the polymer which polymerizes the monomer component in the resin composition for vibration damping materials may become the range mentioned above.

Examples of the water-based crosslinking agent include oxazoline compounds such as Epocross WS-500, WS-700, K-2010, 2020, and 2030 (all trade names, manufactured by Nippon Shokubai Co., Ltd.); Adeka Resin EMN-26-60, EM- Epoxy compounds such as 101-50 (both trade names, manufactured by ADEKA); Melamine compounds such as Cymel C-325 (trade name, manufactured by Mitsui Cytec); Block isocyanate compounds; AZO-50 (trade name, 50% by mass) Zinc oxide compounds such as zinc oxide aqueous dispersion (manufactured by Nippon Shokubai Co., Ltd.) are preferred. The blending amount of the water-based crosslinking agent is, for example, 0.01 to 20 parts by weight in solid content with respect to 100 parts by weight of solid content of the polymer obtained by polymerizing the monomer component in the vibration damping material resin composition. The amount is preferably 0.15 to 15 parts by weight, more preferably 0.5 to 15 parts by weight. By setting such a content of the crosslinking agent, the heat drying property of the coating film is improved, and the vibration damping property can be more fully exhibited without impairing the appearance of the coating film.
The water-based cross-linking agent may be added to a polymer obtained by polymerizing the monomer component before adding the plasticizer and polymer thickener, and other components are blended as a resin composition for vibration damping material. May be added at the same time. By mixing a crosslinking agent with the resin composition for vibration damping material, the toughness of the resin is improved, and as a result, a sufficiently high vibration damping property is exhibited in a high temperature region. Among them, it is preferable to use an oxazoline compound.

Examples of the filler include inorganic fillers such as calcium carbonate, kaolin, silica, talc, barium sulfate, alumina, iron oxide, titanium oxide, glass talk, magnesium carbonate, aluminum hydroxide, talc, diatomaceous earth, and clay; glass Examples of such inorganic fillers include flakes and mica; and fibrous inorganic fillers such as metal oxide whiskers and glass fibers. The blending amount of the filler is preferably 50 to 700 parts by weight, more preferably 100 parts by weight of the solid content of the polymer obtained by polymerizing the monomer component in the vibration damping material resin composition. 100 to 550 parts by weight.

When a particulate filler is used as the filler, the average particle diameter of the filler is preferably 0.5 to 50 μm. More preferably, it is 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 coal (manufactured by Maruo Calcium Co., Ltd.) have the above preferred average particle diameter 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.
Examples of the dispersant include inorganic dispersants such as sodium hexametaphosphate and sodium tripolyphosphate, and organic dispersants such as polycarboxylic acid-based dispersants.
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. In this case, the polyvalent metal compound improves the stability, dispersibility, heat drying property of the vibration damping material resin composition, and the vibration damping properties of the vibration damping material formed from the vibration damping material resin composition. It becomes. It does not specifically limit as a polyvalent metal compound, For example, zinc oxide, zinc chloride, zinc sulfate etc. are mentioned, These 1 type (s) or 2 or more types can be used.
Examples of the form of the polyvalent metal compound may include a powder, an aqueous dispersion, an emulsion dispersion, and the like. Among them, since the dispersibility in the resin composition for vibration damping material is improved, it is preferably used in the form of an aqueous dispersion or an emulsified dispersion, more preferably in the form of an emulsified dispersion. .
The amount of the polyvalent metal compound used is preferably 0.05 to 5.0 parts by weight, more preferably 0.05 parts by weight with respect to 100 parts by weight of the solid content in the vibration damping material resin composition. -3.5 parts by weight.

The resin composition for vibration damping material of the present invention is desirably used as a vibration damping material.
For example, a coating film can be formed by applying a resin composition for vibration damping material to a substrate and drying, and can be used as a vibration damping material.
The resin composition for vibration damping material of the present invention is preferably used as a paint, and can be used by forming a coating film by applying the resin composition for vibration damping material as a paint to a substrate. .
As a method for applying the vibration damping material resin composition to the substrate, for example, a brush, a spatula, an air spray, an airless spray, a mortar gun, a ricin gun or the like can be used.
After applying the resin composition for vibration damping material, the conditions for drying to form a coating film may be heat drying or room temperature drying, but heat drying may be performed in terms of efficiency. preferable. The lower limit of the heat drying temperature is preferably 110 ° C. or higher, and more preferably 120 ° C. or higher. Moreover, as an upper limit of the temperature of heat drying, it is preferable to set it as 210 degrees C or less, More preferably, it is 170 degrees C or less. 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.
Moreover, it can utilize as a damping material also by drying and shape | molding the resin composition for vibration damping materials, producing a coating film, and affixing the said coating film on the required site | part of a base material.

When the resin composition for vibration attenuating material is applied to a vibration attenuating material, the vibration attenuating property can be evaluated by measuring a loss factor of a film formed from the resin composition for vibration attenuating material.
The loss coefficient is usually expressed 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 type FFT analyzer manufactured by Ono Sokki Co., Ltd.
The loss factor is a vibration damping material having a coating capacity of 200 mm length × 10 mm width × 3.0 mm thickness on a cold rolled steel plate (SPCC-SD: length 250 mm × width 10 mm × thickness 1.6 mm). It is preferable to measure by applying the resin composition for coating, drying at 95 ° C. for 30 minutes, and baking and drying at 130 ° C. for 60 minutes to form a film. The loss factor is measured, for example, by 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 measuring each numerical value with a smooth curve. In conclusion, the evaluation is preferably performed 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 of the vibration damping material resin composition is preferably 0 ° C. or higher, more preferably 10 ° C. or higher, and further preferably 20 ° C. or higher. The DPT of the vibration damping material resin composition is preferably 100 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 60 ° C. or lower. When the DPT of the resin composition for vibration damping material of the present invention is in such a range, vibration damping performance in the practical temperature range of the vibration damping material can be more effectively expressed.
Further, since the practical temperature range of the film formed from the vibration damping material resin composition is usually 10 to 60 ° C., the loss at each temperature of 10, 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 coefficients, and the film formed from the resin composition for vibration damping material is at a temperature of 10, 20 ° C., 30 ° C., 40 ° C., 50 ° C. and 60 ° C. It can be said that the greater the total loss factor, the greater the loss factor, the more excellent vibration damping is exhibited in the practical temperature range of 10 to 60 ° C. of the film formed from the resin composition for vibration damping material.

The resin composition for vibration damping material of the present invention has the above-described configuration, exhibits excellent vibration damping properties due to the interaction between the polymer obtained by polymerizing the monomer components and the plasticizer, and the polymer Since it exists in the form of an emulsion in an aqueous solvent, when used as a paint, the dispersion of pigments and the like in the paint becomes good, and the appearance after application becomes good. Therefore, it is a composition that can be suitably used for various applications in which a coating-type vibration damping material is used such as transportation equipment such as railway vehicles, ships, and aircraft, electrical equipment, building structures, and construction equipment.

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%”.

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 previously adjusted to a 20% aqueous solution were added to the dropping funnel. 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, and 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, 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, 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.
Next, 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, 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, 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, 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
Saran latex L123D (trade name, manufactured by Asahi Kasei Chemicals Corporation, vinyl chloride emulsion) was prepared.

Production Example 5
Nalstar SR-115 (trade name, manufactured by Nippon A & L Co., Ltd., SBR emulsion) was prepared.

Production Example 6
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 of methyl methacrylate, 52.5 parts of styrene, 50.0 parts of 2-ethylhexyl acrylate, 140.0 parts of n-butyl acrylate, 7.5 parts of acrylic acid, t-dodecyl mercaptan 2 were added to the dropping funnel. 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, 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, 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.

Production Example 7
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, LATEMUL 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.
After cooling the obtained reaction liquid to room temperature, 11.2 parts of 25% aqueous ammonia was added, and the non-volatile 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 8
400 parts of butyl acetate was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Furthermore, 10% of the monomer premix weighed 260 parts of methyl methacrylate, 240 parts of n-butyl acrylate and 1.0 part of n-dodecyl mercaptan was added to the polymerizer, and the internal temperature was increased while stirring under a nitrogen gas stream. The temperature was raised to 90 ° C. The remaining 90% of the monomer premix was charged into the dropping funnel. Next, while maintaining the internal temperature of the polymerization vessel at 90 ° C., 7.3 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate to a concentration of 2.1% was added. Was added to initiate the initial polymerization. After 10 minutes, the remaining monomer premix was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 90 ° C. At the same time, 65.7 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate so as to have a concentration of 2.1% was uniformly added dropwise over 180 minutes. 30 minutes and 60 minutes after completion of the dropping, 20 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate to a 2.1% concentration as a booster was added in two portions. . The same temperature was maintained for 90 minutes after addition of the booster, and the polymerization was terminated.
After cooling the obtained reaction liquid to room temperature, a resin solution having a nonvolatile content of 50.4%, a viscosity of 3,200 mPa · s, a weight average molecular weight of 110,000, and Tg of 6 ° C. was obtained.

Production Example 9
400 parts of butyl acetate was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Furthermore, among the monomer premixes weighed 250 parts of methyl methacrylate, 52.5 parts of styrene, 140 parts of n-butyl acrylate, 50 parts of 2-ethylhexyl acrylate, 7.5 parts of acrylic acid and 0.8 part of n-dodecyl mercaptan 10% was added to the polymerization vessel, and the internal temperature was raised to 90 ° C. while stirring under a nitrogen gas stream. The remaining 90% of the monomer premix was charged into the dropping funnel. Next, while maintaining the internal temperature of the polymerization vessel at 90 ° C., 7.3 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate to a concentration of 2.1% was added. Was added to initiate the initial polymerization. After 10 minutes, the remaining monomer premix was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 90 ° C. At the same time, 65.7 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate so as to have a concentration of 2.1% was uniformly added dropwise over 180 minutes. 30 minutes and 60 minutes after completion of the dropping, 20 parts of a 2,2′-azobis (2-methylbutyronitrile) solution dissolved in butyl acetate to a 2.1% concentration as a booster was added in two portions. . The same temperature was maintained for 90 minutes after addition of the booster, and the polymerization was terminated.
After cooling the obtained reaction liquid to room temperature, a resin solution having a nonvolatile content of 49.8%, a viscosity of 2,500 mPa · s, a weight average molecular weight of 70,000 and Tg of 19 ° C. was obtained.

Production Example 10
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, in the dropping funnel, 214 parts of methyl methacrylate, 34.5 parts of n-butyl acrylate, 1.5 parts of acrylic acid, 0.1 part of t-dodecyl mercaptan, Levenol WZ (trade name, A first stage monomer emulsion consisting of 45 parts Kao) 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, 147 parts of methyl methacrylate, 97.5 parts of n-butyl acrylate, 5.5 parts of acrylic acid, 0.1 part of t-dodecyl mercaptan, and Lebenol WZ (trade name, Kao Corporation) previously adjusted to a 20% aqueous solution were added to the dropping funnel. (Manufactured) A second stage monomer emulsion consisting of 45 parts and deionized water 48.5 parts 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, 2.6 parts of 25% aqueous ammonia was added, and the non-volatile content was 54.9%, pH 7.2, viscosity 300 mPa · s, average particle diameter 190 nm, weight average molecular weight 200,000, An emulsion having a first stage Tg of 20 ° C., a second stage Tg of 90 ° C., and a total Tg of 43 ° C. was obtained.

(Examples 1 to 11, Comparative Examples 1 to 4)
As shown in Table 1, plasticizers (1) to (5) were added to the polymers (emulsions or resin solutions) prepared in Production Examples 1 to 10 to prepare mixtures of polymers and plasticizers.
Table 1 shows the addition amount of the plasticizer as a ratio (% by weight) to the total nonvolatile content of the polymer and the plasticizer of 100% by weight.
Furthermore, the following component was mix | blended with the mixture of a polymer and a plasticizer, and the resin composition for vibration damping materials was obtained.

Polymer and plasticizer mixture 359 parts Calcium carbonate (NN # 200 ^{* 1} ) 620 parts Carbon black 1 part Starch 46.8 parts Dispersant (Aquaric DL-40S ^{* 2} ) 6 parts Thickener 4 parts (Example 1, (4-7, 11, Comparative Examples 1-3 used A, Examples 2, 8, 10 used B, Example 3 used C, and Example 9 used D)
A: Acre Reset WR-650 ^{* 3}
B: Axle reset WR-503A ^{* 4}
C: Primal TT-615 ^{* 5}
D: Primal ASE-95 ^{* 6}
Defoaming agent (Nopco 8034L ^{* 7} ) 1 part Foaming agent (F-30 ^{* 8} ) 6 parts * 1: Filling material (average particle size 20μm) manufactured by Nitto Flourishing Co., Ltd.
* 2: Nippon Shokubai Co., Ltd. polycarboxylic acid type dispersant (active ingredient 44%)
* 3: Nippon Shokubai Co., Ltd. alkali-soluble acrylic thickener (active ingredient 30%)
* 4: Made by Nippon Shokubai Co., Ltd. Alkali-soluble acrylic thickener (active ingredient 30%)
* 5: Rohm & Haas Co., Ltd. Alkali-soluble acrylic thickener (30% active ingredient)
* 6: Rohm & Haas Co., Ltd. Alkali-soluble acrylic thickener, Newton fluidity-imparting type (30% active ingredient)
* 7: Defoaming agent (main component: hydrophobic silicone + mineral oil) manufactured by San Nopco Co., Ltd.
* 8: Matsumoto Yushi Co., Ltd. foaming agent

<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 measurement of vibration damping uses the cantilever method (loss factor measurement system, Ono Sokki Co., Ltd.) to resonate the loss factor η at 10 ° C, 20 ° C, 30 ° C, 40 ° C, 50 ° C and 60 ° C. Measured by the 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 0.46 or more, and if it is 0.46 or more, sufficient vibration damping performance is achieved in the practical temperature range. It can be said that it has.
Note that the half-value width indicates the temperature width of the peak at a portion where the peak top value of the loss coefficient is halved, and DPT indicates the peak temperature of the loss coefficient. 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 0.46 or more, and less than 0.46 is x.

<Observation of pigment dispersibility and coating film appearance>
The appearance of the coating film formed in the vibration damping test was observed, and the pigment dispersibility, the sagging during coating, and the coating film appearance were evaluated.
The evaluation results are shown in Table 1.
<Pigment dispersibility>
The pigment dispersibility was evaluated by visual observation of the obtained resin composition for vibration damping material. The evaluation criteria are as follows.
○: Appearance of smooth and uniform carbon coloring without pigment lumps ×: Appearance of pigment lumps or non-uniform carbon coloring <sag during application>
The sagging during coating is an electrodeposited steel plate (epoxy cationic electrodeposition coating plate: Nippon Test Panel Co., Ltd., width 70 mm × length 150 mm × thickness 0.8 mm) and thickness 4 mm. It was evaluated by measuring the length of the sagging at the bottom of the coating film after heat treatment at 60 ° C. for 30 minutes. The evaluation criteria are as follows.
A: Less than 10 mm B: 10 mm to less than 15 mm X: 15 mm or more <Appearance of coating film>
The visual appearance of the coating film formed in the vibration damping test was confirmed. The evaluation criteria are as follows.
○: No crack in the coating film ×: Cracking of the coating film means cracking in a state of peeling at the interface with the steel sheet, cracking of the coating film surface, and the like.

<Evaluation of coating film properties>
About the coating film formed by the said vibration damping test, the coating film impact resistance, coating film bending, and coating film thickness were evaluated.
The evaluation results are shown in Table 1.
<Evaluation of impact resistance>
The appearance of the coating film was observed when a steel ball having a weight of 100 g was dropped from a height of 30 cm on the coating film surface of the test piece formed in the vibration damping test. The evaluation criteria are as follows.
The test temperature was the peak temperature of the loss factor.
○: No cracking or peeling of coating film ×: Cracking or peeling of coating film <Evaluation of coating film bending>
The state of the coating film when the center part of the test piece formed by the vibration damping test was bent 30 degrees in the direction opposite to the coating surface of the coating film was confirmed. The evaluation criteria are as follows.
The test temperature was the peak temperature of the loss factor.
○: No cracking or peeling of coating film ×: Cracking or peeling of coating film <Evaluation of coating film thickness>
The thickness of the coating film excluding the steel plate of the test piece formed in the vibration damping test was evaluated.
The film thickness was shown as a relative value with the film thickness of Comparative Example 1 being 1.0.

In Table 1, plasticizers (1) to (5) represent the following, respectively.
(1): 2,2′-methylenebis (4-ethyl-6-tert-butylphenol) (trade name: NOCRACK NS-6, manufactured by Ouchi Shinsei Chemical Co., Ltd.)
(2): N, N-dicyclohexylbenzothiazole-2-sulfenamide (manufactured by Wako Pure Chemical Industries, Ltd.)
(3): Styrenated phenol (Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK SP)
(4): Octylated diphenylamine (Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK AD-F)
(5): Alkylated diphenylamine (Ouchi Shinsei Chemical Co., Ltd., trade name: NOCRACK ODA)

In the resin compositions for vibration damping materials of Examples 1 to 9, the peak height of the loss factor is higher than 0.15, and the value of peak height × half-value width is also higher than 4.5. Furthermore, since the total loss coefficient at 10 ° C. to 60 ° C. exceeds 0.46, the vibration damping action is large and excellent characteristics are exhibited. Moreover, the pigment dispersibility and the coating film appearance were also excellent.
Also, in the resin compositions for vibration damping materials of Examples 10 and 11 in which two types of polymers were mixed, the peak height of the loss factor was as high as 0.14 or more, and the value of peak height × half-value width Furthermore, since the total loss coefficient of 10 ° C. to 60 ° C. exceeds 0.46, the vibration damping action is large and excellent characteristics are exhibited. Moreover, the pigment dispersibility and the coating film appearance were also excellent.

Claims

Including a polymer obtained by polymerizing monomer components and a plasticizer,
A resin composition for vibration damping material, wherein the polymer is an aqueous composition in the form of an emulsion in an aqueous solvent.
2. The vibration damping material resin according to claim 1, wherein the plasticizer is contained in the polymer, or the plasticizer is an aqueous composition in the form of an emulsion in an aqueous solvent. Composition.
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.
The resin composition for vibration damping material according to any one of claims 1 to 3, further comprising a polymer thickener.
The polymer thickener includes polyvinyl alcohol thickener, polyvinylpyrrolidone thickener, unsaturated carboxylic acid (co) polymer thickener, cellulose derivative thickener, and modified polyether urethane. The resin composition for vibration damping material according to claim 4, wherein the resin composition is at least one selected from the group consisting of a system thickener.
The resin composition for vibration damping materials according to claim 4 or 5, wherein the polymer-based thickener has a weight average molecular weight of 300,000 or more.
Ratio of low shear viscosity (η1) measured at 2 rpm using a B-type rotational viscometer and high shear viscosity (η2) measured at 20 rpm using a B-type rotational viscometer of the resin composition for vibration damping material 7. The resin composition for vibration damping material according to claim 1, wherein (η1 / η2) is 1 to 9.
The resin composition for vibration damping material according to any one of claims 1 to 7, further comprising a pigment.