JPH11293020A - Foamed composition for sealing and method of use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat resistance, adhesiveness and waterproofness by blending a rubber-like organic polymer having reactive silicon groups, a silanol condensation catalyst and an organic decompositional foaming agent to give a viscosity appropriate for coating and a stability of the foaming ratio. SOLUTION: This composition comprises 100 parts by weight of a rubber-like organic polymer having a molecular weight of 500-50,000, preferably 1,000-20,000 and containing at least one reactive silicon group of formula I or II (wherein X is hydroxide or a hydrolyzable group; R<1> is a 1-20C monovalent hydrocarbon group or a siloxy wherein Si is bonded with a 1-20C monovalent hydrocarbon group; a is 1-3; b is 0-2; 1<=a+b; m is 0-18; R<2> is a 1-18C monovalent hydrocarbon group; and n is 1-3), 1-10, preferably 1-4, parts by weight of a silanol condensation catalyst, 5-30, preferably 10 25, parts by weight of an organic decompositional foaming agent, and optionally 20-80 parts by weight of an epoxy resin having not less than two oxysilane rings in a molecule with 2-8 wt.% of an epoxy resin curing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamable sealing composition suitable for sealing applications such as sealing materials and gaskets, and a method of using the same.

[0002]

2. Description of the Related Art Conventionally, as a foamable resin composition, SB
In addition to hot-melt systems using a block polymer such as S or SIS as a resin component (JP-B-7-17896, etc.),
Polyurethanes and epoxies are known, but each has the following advantages and disadvantages.

A foamable resin composition containing a block polymer such as SBS or SIS as a resin component has a hot-melt property and therefore has an advantage in use. However, the softening point of the block polymer such as SBS or SIS is, for example, 60 ° C. Therefore, there is a problem that heat resistance is low and it is difficult to use for sealing applications. For sealing applications, adhesiveness not only at room temperature but also at high temperature is required. However, the hot-melt foamable resin composition has a great problem also in this point.

[0004] The epoxy foamable resin composition hardly causes a problem of heat resistance and has sufficiently high adhesion. However, there is a problem that cracks and missing parts are apt to occur because of poor flexibility and easy cracking. On the other hand, since the polyurethane-based foamable resin composition has appropriate elasticity, it is excellent in durability, abrasion resistance and the like, and does not cause problems such as cracks and chipping. However, not only the adhesion at a high temperature but also the adhesion at a normal temperature is low, and there is a serious drawback in sealing applications that the interface is easily broken.

Until now, foamable resin compositions have been usually foamed with halogenated carbon (CFC). This is because foaming with a gas can easily obtain a sufficient foaming ratio. However, the gas foaming method using chlorofluorocarbon has a problem that the dimensions after foaming are apt to vary and the waterproofness is low, and fluorocarbons destroy the ozone layer. , Can not be used.

As another foaming method, there is a method of foaming using a reactive foaming agent such as isocyanate. In this foaming method, air bubbles often tend to be open cells, are poor in waterproofness, and have sufficient foaming. The magnification cannot be obtained.

[0007]

The problem to be solved by the present invention is to provide an appropriate viscosity for coating, heat resistance, and sufficient foaming ratio without using Freon. Is obtained, and its foaming ratio is stable, and has sufficient adhesion even at normal temperature or high temperature,
An object of the present invention is to provide a foam-type sealing composition having high waterproofness and a method for using the same.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, in order to obtain heat resistance and appropriate elasticity, select a rubber organic polymer as a resin component. It was to be. This is because the rubbery organic polymer has an appropriate viscosity at room temperature and is excellent in coatability. Then, a reactive silicon group was introduced into this rubbery organic polymer, and this was cured with a silanol condensation catalyst to form a crosslinked structure. This is because sufficient adhesion can be obtained not only at room temperature but also at high temperature, and the waterproofness can be enhanced. Next, an organic thermal decomposition type foaming agent was selected as a foaming agent. This is because the foaming method using an organic thermal decomposition type foaming agent can obtain a sufficient foaming ratio and also has good dimensional stability after foaming. The present invention has been completed as described above.

Therefore, the foamable sealing composition according to the present invention comprises a rubbery organic polymer containing at least one reactive silicon group, a silanol condensation catalyst for curing the rubbery organic polymer, Organic thermal decomposition type foaming agent. The composition has at least one selected from an epoxy resin having two or more oxirane rings in one molecule, a curing catalyst for curing the epoxy resin, a silane coupling agent, a tackifying resin, and a conductor that generates heat by induction heating. Seeds can be further included. This composition may be a sealant which is a final product.

The method of using the foam-type sealing composition according to the present invention is a method of heating and foaming the foam-type sealing composition, and the heating can be performed by high-frequency heating.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, first, essential components and preferable additional components constituting the foam-type sealing composition of the present invention will be described, and then, the structure and usage of the foam-type sealing composition will be described. I do. (Reactive silicon group-containing rubber organic polymer) The polymer chain that is the main component of the reactive silicon group-containing rubber organic polymer,
For example, it is derived from the following rubbery organic polymer. That is, a polyester-based polymer obtained by a condensation reaction of a dibasic acid such as adipic acid with glycol or a ring-opening reaction of a lactone; an ethylene-propylene-based copolymer; a polyisobutylene; a copolymer of isobutylene and isoprene; Polychloroprene; polyisoprene; a copolymer of isoprene with butadiene, styrene, acrylonitrile, etc .; polybutadiene; a copolymer of butadiene with styrene, acrylonitrile, etc .; a copolymer of polyisoprene, polybutadiene, isoprene or butadiene with styrene, acrylonitrile, etc. Polyolefin polymer obtained by hydrogenating a copolymer; Polyacrylic ester obtained by radical polymerization of monomers such as ethyl acrylate and butyl acrylate; Acrylic such as ethyl acrylate and butyl acrylate An acrylate polymer obtained by copolymerizing an ester and a monomer such as vinyl acetate, acrylonitrile, methyl methacrylate, or styrene; a vinyl monomer is graft-polymerized to the various rubbery organic polymers exemplified above. A polyether-based polymer obtained by polymerization of a cyclic ether such as propylene oxide, ethylene oxide, or tetrahydrofuran (wherein the main chain is -RO- (where R is 2 to 2 carbon atoms)
4 represents two alkylene groups. A) a polymer represented by
Among them, a vinyl polymer-modified polyether polymer obtained by polymerizing an ester of an alcohol having 1 to 13 carbon atoms and (meth) acrylic acid, vinyl acetate, acrylonitrile, styrene, etc .; a polysulfide polymer, etc. It is. Among these, as the rubber-based organic polymer, a vinyl polymer-modified polyether-based polymer obtained by polymerizing a vinyl monomer such as ethyl acrylate or butyl acrylate in a propylene oxide-based polyether; a polyacrylate ester; Acrylic esters and copolymers of vinyl acetate, acrylonitrile, methyl methacrylate, styrene and the like are preferred.

The rubbery organic polymer may have a branched structure or a linear structure. The molecular weight of the rubbery organic polymer is not particularly limited, and is preferably from 500 to 50,000, and more preferably from 1,000 to 50,000.
0 to 20,000. If the molecular weight of the rubber-based organic polymer is less than 500, elongation may be reduced upon curing and the hardness may be increased. On the other hand, when the molecular weight of the rubbery organic polymer exceeds 50,000, elongation increases when cured, and the tensile strength may be too low. At the same time, the viscosity increases, making it difficult to handle.

The rubbery organic polymer used in the present invention comprises:
The molecule contains at least one reactive silicon group. Examples of the reactive silicon group include a hydrolyzable silicon group and a silanol group. Here, the hydrolyzable silicon group is a group in which a group that is decomposed by moisture is bonded to a silicon atom. Silanol groups can also be obtained by hydrolyzing hydrolyzable silicon groups. The number of silicon atoms in the reactive silicon group may be one, or two or more. When the reactive silicon group contains a divalent siloxane group, the number of silicon atoms in the reactive silicon group can be freely used as long as the number is up to 20.

Specific examples of the reactive silicon group include the reactive silicon groups represented by the following general formulas (1) and (2). The reactive silicon group is bonded via a silicon-carbon bond to a polymer chain that is a main component of the rubbery organic polymer.

[0015]

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(Wherein X is a hydroxyl group or a hydrolyzable group;
R ¹ is a monovalent hydrocarbon group having 1 to 20 carbon atoms or a siloxy group in which a monovalent hydrocarbon group having 1 to 20 carbon atoms is bonded to a silicon atom; a is an integer of 1 to 3; Integer of 1 ≦
a + b; m = 0 to 18; )

[0017]

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(Wherein X is a hydroxyl group or a hydrolyzable group;
R ² is a monovalent hydrocarbon group having 1 to 18 carbon atoms; n = 1 to 3
Is an integer. The hydrolyzable group used as X includes, for example,
Examples include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyloxy group. 2
More than one species can coexist. Among these groups, an alkoxy group is preferred because it is mild in hydrolysis and easy to handle.

To explain, taking a hydrolyzable silicon group as an example, there are the following methods (a) to (d) as a method for introducing a reactive silicon group into a rubbery organic polymer. (A) a monomer having a copolymerizable unsaturated group such as vinyl trialkoxysilane, methacryloxypropylmethyl dialkoxysilane, methacryloxypropyl trialkoxysilane and a hydrolyzable silicon group in the molecule, ethylene, propylene, A method of copolymerizing with a polymerizable monomer such as isobutylene, chloroprene, isoprene, butadiene, or an acrylate ester; and a copolymerizable epoxy group such as γ-glycidoxypropyltrimethoxysilane or γ-glycidoxypropylmethyldimethoxysilane. A method in which a monomer having a hydrolyzable silicon group in a molecule is copolymerized with propylene oxide, ethylene oxide, or the like.

(B) A silicon compound having a mercapto group or disulfide group such as mercaptopropyl trialkoxysilane or mercaptopropylmethyldialkoxysilane which can cause a chain transfer reaction in radical polymerization and a hydrolyzable silicon group in the molecule. A method in which a radical polymerizable monomer is polymerized by using it as a chain transfer agent. (C) azobis-2- (6-methyldiethoxysilyl-
A method of polymerizing a radical polymerizable monomer using an azo-based initiator or a peroxide-based initiator containing a hydrolyzable silicon group such as 2-cyanohexane).

(D) a hydroxyl group, a carboxyl group, a mercapto group, an epoxy group,
For a polymer having a functional group such as an isocyanate group, a silicon compound containing another functional group capable of reacting with this functional group in the molecule and also containing a hydrolyzable silicon group is reacted with both functional groups. How to combine with. According to the method (a), a hydrolyzable silicon group can be introduced into the side chain of the polymer molecule. According to the above methods (b) and (c), a hydrolyzable silicon group can be introduced into the terminal of the polymer chain. [Silanol condensation catalyst] The silanol condensation catalyst promotes the condensation reaction (curing reaction) of the reactive silicon group in the rubbery organic polymer.

As the silanol condensation catalyst, for example,
Titanate such as tetrabutyl titanate and tetrapropyl titanate; dibutyltin dilaurate, dibutyltin maleate, dibutyltin acetate, tin octylate, tin naphthenate, a reaction product of dibutyltin oxide and phthalate, and organic such as dibutyltin diacetylacetonate Tin compounds; organoaluminum compounds such as aluminum trisacetylacetonate, aluminum trisethylacetoacetonate, diisopropoxyaluminum trisethylacetoacetonate; chelate compounds such as zirconium tetraacetylacetonate, titanium tetraacetylacetonate; Organic lead compounds such as lead octylate; butylamine,
Octylamine, laurylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine, xylylenediamine, triethylenediamine, guanidine, diphenylguanidine, 2 , 4,6-tris (dimethylaminomethyl) phenol, morpholine, N-methylmorpholine, 2-ethyl-4-methylimidazole, 1,8-
Diazabicyclo [5.4.0] undecene-7 (DB
Amine compounds such as U); carboxylate salts of the amine compounds; low-molecular-weight polyamide resins obtained from excess polyamine and polybasic acid; reaction products of excess polyamine and epoxy compound; , These are 1
Seeds or two or more are used.

Among the above silanol condensation catalysts, organometallic compounds and a combination of an organometallic compound and an amine compound are preferable and have high curability. As the organometallic compounds, organotin compounds are preferred, and tetravalent organotin compounds are more preferred. 4 as silanol condensation catalyst
When a valence organic tin compound is used and a compound containing a primary or secondary amino group and a hydrolyzable silicon group is used as a silane coupling agent, the elastic modulus and strength are increased. [Organic thermal decomposition type foaming agent] The organic thermal decomposition type foaming agent, when heated, foams the sealing composition with good reproducibility and sufficient expansion ratio.

Examples of the organic thermal decomposition type foaming agent include azo compounds such as azodicarbonamide; N, N '
Nitroso compounds such as -dinitropentamethylenetetramine; hydrazine derivatives such as 4,4'-oxybis (benzenesulfonylhydrazide) and hydrazocarbonamide; azide compounds; and triazole compounds. Used above.

In the present invention, an inorganic thermal decomposition type foaming agent may be used together with the organic thermal decomposition type foaming agent. Examples of the inorganic pyrolytic foaming agent include bicarbonate, carbonate,
Nitrite, hydrogen compounds and the like can be mentioned, and one or more of these are used. [Epoxy Resin and Curing Catalyst Thereof] The epoxy resin used in the present invention can form a network structure by being cross-linked, and greatly contributes to the improvement in adhesion and heat resistance of the foam-type sealing composition.

The epoxy resin used in the present invention is not particularly limited, and for example, epichlorohydrin-
Bisphenol A epoxy resin; epichlorohydrin-bisphenol F epoxy resin; epichlorohydrin-bisphenol S epoxy resin; flame-retardant epoxy resin such as glycidyl ether of tetrabromobisphenol A; novolak epoxy resin; hydrogenated Bisphenol A type epoxy resin; glycidyl ether type epoxy resin of bisphenol A type propylene oxide adduct,
Glycidyl ether type epoxy resin of bisphenol A type ethylene oxide adduct; glycidyl-p-oxybenzoic acid, diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, diglycidyl adipate, etc. Sil ester type epoxy resin; triglycidyl-m-aminophenol, N, N, N ', N'-
Tetraglycidyldiaminodiphenylmethane, N, N-
Glycidylamine type epoxy resins such as glycidylaniline and N, N-diglycidyl-o-toluidine; 1,3-
Hydantoin type epoxy resins such as diglycidyl-5-methyl-5-ethylhydantoin; triglycidyl isocyanurate; polyalkylene glycol diglycidyl ether; glycidyl ether of polyhydric alcohols such as glycerin and sorbitol; alicyclic diepoxy acetal, alisai Cycloaliphatic epoxy resins such as click diepoxy adipate, alicyclic diepoxy carboxylate, and vinylcyclohexene oxide; epoxidized unsaturated polymers such as polybutadiene and petroleum resins; Two or more are used. Among them, an epoxy resin having two or more epoxy groups is preferable because it easily forms a crosslinked structure. It is more preferable that the epoxy resin is an epichlorohydrin-bisphenol A type epoxy resin because the compatibility with the rubbery organic polymer is high.

As a catalyst for curing the epoxy resin, for example, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-
Primary and secondary such as aminoethylpiperazine, mensendiamine, isophoronediamine, morpholine, piperidine, m-xylylenediamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfonic acid, etc.
Grade amines; trialkylamine, N-methylmorpholine, N, N'-dimethylpiperazine, pyridine, picoline, guanidine, diphenylguanidine, 1,8-diazabicyclo [5.4.0] undecene-7 (DB
U), tertiary amines such as benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol and organic acid salts thereof; 2-methylimidazole, 2-ethyl- 4-methylimidazole, 2-undecylimidazole, 1-
Imidazoles such as benzyl-2-methylimidazole; polyamide resins; dicyandiamides; boron trifluoride-amine complex; phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, dodecylsuccinic anhydride Carboxylic anhydrides, such as, trimellitic anhydride, pyromellitic anhydride, chlorenic anhydride; alcohols; phenols;
Carboxylic acids: Lewis acids such as boron trifluoride, phosphorus hexafluoride, aluminum trichloride, and tin chloride, and salts thereof, and the like, and one or more of these can be used. Of these, tertiary amines, their organic acid salts, and imidazoles are preferable because of their high curability. [Silane Coupling Agent] The silane coupling agent is a functional group-containing silane containing a hydrolyzable silicon group and another functional group in one molecule. In the matrix), islands (domains) containing the epoxy resin are uniformly dispersed and exert an effect of stabilizing.

Other functional groups contained in the functional group-containing silanes include, for example, primary, secondary, and tertiary amino groups, mercapto groups, epoxy groups, ureido groups, isocyanate groups, vinyl groups, methacryl groups, Examples include a halogenoalkyl group. Among these, as the other functional groups, primary, secondary, and tertiary amino groups, mercapto groups, epoxy groups, ureido groups, and the like that can react with both the rubbery organic polymer and the epoxy resin are preferable. 1st grade, 2nd grade
Primary and tertiary amino groups are more preferred, and primary and secondary amino groups are most preferred.

Examples of the hydrolyzable silicon group contained in the functional group-containing silanes include a reactive silicon group (A) in which X is a hydrolyzable group, and among these, an alkoxysilyl group Is preferred. Examples of the functional group-containing silanes include N-β- (aminoethyl)-
γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ
-(2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl)
Aminopropylmethyldiethoxysilane, γ- (2-aminopentyl) aminopropyltrimethoxysilane, γ
-(2-aminopentyl) aminopropyltriethoxysilane, γ- (2-aminopentyl) aminopropylmethyldimethoxysilane, γ- (2-aminopentyl) aminopropylmethyldiethoxysilane, N-β- (N-
Amino group-containing silanes such as vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane and γ-anilinopropyltrimethoxysilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropyl Mercapto group-containing silanes such as methyldimethoxysilane and γ-mercaptopropylmethyldiethoxysilane; γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β
Epoxy group-containing silanes such as-(3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane; γ-ureidopropyltrimethoxysilane;
Ureido group-containing silanes such as [gamma] -ureidopropyltriethoxysilane, [gamma] -ureidopropylmethyldimethoxysilane, [gamma] -ureidopropylmethyldiethoxysilane and the like can be mentioned, and one or more of these can be used. (Tackifying resin) Tackifying resin used in the present invention,
Demonstrates the effect of improving adhesion and waterproofness.

Examples of the tackifying resin include rosin, rosin ester, aromatic petroleum resin, terpene phenol resin, and coumarone-indene resin, and one or more of these are used. For the softening point of the tackifier resin, the lower the softening point, the lower the adhesive strength at normal temperature until moisture curing proceeds, and the higher the softening point, the higher the melting temperature needs to be raised, because thermal stability becomes a problem.
The softening point is preferably from 70 to 130C, more preferably from 70 to 100C. [Foam-type sealing composition and method of using the same] The foam-type sealing composition according to the present invention is a composition containing the essential components and the preferable additional components described above, and becomes a sealing material as a final product as it is. In addition, it may be an intermediate product that is a raw material for sealing materials.

The proportion of the silanol condensation catalyst in the foam-type sealing composition is not particularly limited, but is preferably 1 to 10 parts by weight based on 100 parts by weight of the rubbery organic polymer.
Parts by weight, more preferably 1 to 4 parts by weight.
If the ratio of the silanol condensation catalyst is less than 1 part by weight, curing may be insufficient and heat resistance may decrease. On the other hand, if the ratio of the silanol condensation catalyst exceeds 10 parts by weight, the composition may be too hard to cure and may be difficult to handle.

The ratio of the organic thermal decomposition type foaming agent in the foam type sealing composition is not particularly limited, but is preferably 5 to 3 parts by weight per 100 parts by weight of the rubbery organic polymer.
0 parts by weight, more preferably 10 to 25 parts by weight. If the proportion of the organic thermal decomposition type foaming agent is less than 5 parts by weight, the foam cannot be sufficiently foamed, and a stable foaming ratio may not be obtained. On the other hand, when the proportion of the organic thermal decomposition type foaming agent exceeds 30 parts by weight, the expansion ratio becomes too high, and the resin tends to contract and expand, and the adhesion and the waterproofness may be reduced.

The foam-type sealing composition of the present invention may further contain an epoxy resin and a curing catalyst thereof. The proportion of the epoxy resin in the foam-type sealing composition is not particularly limited, but is preferably 20 to 80 parts by weight, more preferably 40 to 60 parts by weight, per 100 parts by weight of the rubbery organic polymer. Department. If the proportion of the epoxy resin is less than 20 parts by weight, there is a possibility that the adhesion and the waterproofness are reduced. On the other hand, if the proportion of the epoxy resin exceeds 80 parts by weight, the flexibility as a sealing agent may be reduced. The ratio of the epoxy resin curing agent is not particularly limited, but is preferably 2% of the epoxy resin.
-8% by weight, more preferably 4-6% by weight. If the proportion of the epoxy resin curing agent is less than 2% by weight, the curing reaction of the epoxy resin may be slow.
On the other hand, when the proportion of the epoxy resin curing agent exceeds 8 parts by weight, the unreacted epoxy resin curing agent remains after curing, and is likely to be plasticized, which may lower heat resistance.

The foam-type sealing composition of the present invention may further contain a silane coupling agent. The proportion of the silane coupling agent in the foam-type sealing composition is not particularly limited, but is preferably 1 to 10 parts by weight, more preferably 1 to 10 parts by weight, based on 100 parts by weight of the rubbery organic polymer. 7 parts by weight, most preferably 1 to 5 parts by weight. If the ratio of the silane coupling is less than 1 part by weight, the rubbery organic polymer and the epoxy resin are not uniformly dispersed, and the adhesion and heat resistance may be reduced. On the other hand, when the proportion of the silane coupling exceeds 10 parts by weight, the curing reaction may be accelerated and the handling may be difficult.

The foam-type sealing composition of the present invention may further contain a tackifier resin. The proportion of the tackifying resin in the foam-type sealing composition is not particularly limited, but is preferably 5 to 20 parts by weight, more preferably 5 to 20 parts by weight, based on 100 parts by weight of the rubbery organic polymer.
15 parts by weight. If the proportion of the tackifier resin is less than 5 parts by weight, the adhesion and waterproofness may be reduced, and the cohesive strength may be reduced. On the other hand, if the proportion of the tackifier resin exceeds 20 parts by weight, the viscosity may increase, and handling may be difficult.

The foam-type sealing composition of the present invention may further contain a conductor which generates heat by induction heating. In this case, the foam can be foamed uniformly in a short time, the expansion ratio is stable, and the adhesion can be improved. The properties and waterproofness are further improved. Induction heating is performed by, for example, high frequency. Examples of the conductor include metals such as silver and iron;
Carbon and the like can be mentioned, and these are used alone or in combination of two or more.

The form of the conductor is not particularly limited, and may be any form such as a powder form and a granular form.
Powders that generate heat more uniformly are preferred. The proportion of the conductor in the foam-type sealing composition is not particularly limited, but is preferably 1 to 10 parts by weight, more preferably 2 to 8 parts by weight, per 100 parts by weight of the rubbery organic polymer. Parts, most preferably 4 to 6 parts by weight. When the proportion of the conductor is less than 1 part by weight, the expansion ratio is not stable, and there is a possibility that the adhesion and the waterproofness are reduced. On the other hand, if the proportion of the conductor exceeds 10 parts by weight, the curing reaction will be fast, the working viscosity will be high, and the handling may be difficult.

The foam-type sealing composition of the present invention may contain the following components. Storage stability improvers such as carboxylic acids used to stabilize rubbery organic polymers, silanol condensation catalysts, fillers, etc .; dehydrating agents; compatibilizers; adhesion improvers; Antioxidants; ultraviolet absorbers; metal deactivators; antiozonants; light stabilizers; amine radical chain inhibitors; phosphorus peroxide decomposers; pigments; These are 1
Seeds or two or more are used.

The foam-type sealing composition of the present invention can be prepared by mixing the above-mentioned components and kneading them using a mixer, roll, kneader or the like. In consideration of the reactivity and storage stability of the foam-type sealing composition, it is preferably prepared immediately before use. The foam-type sealing composition may be a composition composed of a combination of two liquids, liquid A and liquid B described below. In this case, a liquid A and a liquid B prepared in advance are mixed immediately before use to obtain a foamable sealing composition. As a configuration of the liquid A and the liquid B, for example,
(1) Liquid A which essentially requires a silanol condensation catalyst, and B which essentially contains a rubbery organic polymer and an organic thermal decomposition type blowing agent
A combination of liquids is preferable, (2) liquid A containing an epoxy resin and a silanol condensation catalyst and a rubbery organic polymer,
A combination of a liquid B containing a silane coupling agent, an epoxy resin curing agent and an organic thermal decomposition type foaming agent is more preferable. In the above combination, two components that are easily reacted, that is, the epoxy resin and the epoxy resin curing agent, the rubbery organic polymer, and the silanol condensation catalyst can be separately separated, so that the storage stability of the composition is increased.

The foam-type sealing composition according to the present invention can be foamed and cured by heating, and has excellent adhesion, waterproofness and heat resistance, and a stable and sufficient expansion ratio can be obtained. , Pre-sealing material, gasket material and the like. FIG. 1 shows an example of an architectural outer wall material obtained by using a foam-type sealing composition as a pre-sealing material. Exterior wall material for construction 1
Is attached to the lap joint portion 3a of the plate-shaped outer wall material body 2,
A pre-sealing portion 3b is obtained by applying a pre-sealing material in a bead shape, and then foaming and curing the pre-sealing material. Regarding the method of applying the pre-sealing material to the lap joint portion 3a of the outer wall material main body 2 in a bead shape,
Although not particularly limited, for example, the outer wall material body 2 is
A method of applying a pre-sealing material to a bead width of 2 to 10 mm using an applicator while heating to 00 ° C. can be used. The outer wall material main body 2 is not particularly limited as long as it has a plate shape, and any material, thickness, and size are used.

As a heating method for foaming and curing the pre-sealing material applied to the lap joint,
For example, the following methods can be mentioned, and these methods may be combined. Using a drier or the like, apply 1% to the pre-sealing material applied to the outer wall material
A method of blowing hot air at 40 to 160 ° C.

The pre-sealing material applied material is
A method in which it is left in an atmosphere at a temperature of 120 ° C. A method in which high-frequency heating is applied to the pre-sealing material application. Among the above methods, the method can uniformly foam the pre-sealing material in a short time. According to the method, since the rubber organic polymer contained in the pre-sealing material is an insulator, dielectric heating is performed by high frequency, and the inside can be sufficiently heated in a short time. In addition, in the method, when the pre-sealing material includes a conductor that generates heat by induction heating, the high-frequency heating is performed by induction heating, and parts other than the pre-sealing material such as the outer wall material main body are generally not heated. It will not be deformed or damaged.

The foamed and cured pre-sealing material is, for example, allowed to stand at room temperature for about 3 to 7 days.
The cure can be completed by leaving it at about 3 days. The architectural outer wall material thus obtained is used for an outer wall of a prefabricated house. It is preferable that the manufacture of the building outer wall material is performed not in the construction site but in the factory, thereby shortening the joint finishing work at the construction site and shortening the number of days of house construction. Because.

The foam-type sealing composition according to the present invention can also be used for gasket applications such as moldings for automobile window glasses and other applications. Other uses include sealing inner and outer boxes of refrigerators, packing can lids, and the like. Also in these cases, foaming and curing can be performed by the same heating method as described above. FIG. 2 shows an example in which the present invention is used for a window glass molding of an automobile. The window glass 5 and the body 6 of the automobile are fixed via an adhesive layer 7, and the adhesive layer 7 is sandwiched between the dam rubber 8 and the molding 4. Since the molding 4 is obtained by using the foam-type sealing composition according to the present invention, the molding 4 has high adhesion to the window glass 5 and the body 6, and a gap is formed between the window glass 5 and the body 6. Without
Get high waterproofness and airtightness.

FIG. 3 shows an example used for a refrigerator seal. The inner box 10 and the outer box 11 of the refrigerator are fixed by a seal 9. Since the seal 9 is obtained by using the foam-type sealing composition according to the present invention, the seal 9 has excellent heat resistance, and has high adhesion to the inner box 10 and the outer box 11, and is high in the inner box 10. Get airtight. FIG. 4 shows an example of use for a can lid with packing. Can lid with packing 12
The foaming type sealing composition according to the present invention is applied to the outer periphery of a plate-shaped can lid body 13 in a bead shape, and then foamed and cured to form a packing 14. Packing 1
No. 4 has high adhesiveness and greatly maintains the airtightness inside the can.

[0046]

EXAMPLES Examples of the present invention and comparative examples are shown below, but the present invention is not limited to the following examples. Hereinafter, “parts” indicates “parts by weight”. Example 1-1 Four parts of a di-n-butyltin-based catalyst (trade name: No. 918, manufactured by Sankyoki Gosei Co., Ltd.) as a silanol condensation catalyst was used as Liquid A. Next, a modified silicone oligomer (trade name: SAT-2) as a rubbery organic polymer
00, manufactured by Kanegabuchi Chemical Industry Co., Ltd.), 100 parts of N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane (trade name: A-1122, manufactured by Nippon Unicar) as a silane coupling agent, 50 parts of hydroxyapatite (trade name: HAP BC, 325 mesh pass, manufactured by Nitta Gelatin Co., Ltd.) as an adhesion improver, hydrazine derivative (trade name: Neoserbon N # 5000, Eiwa Chemical Co., Ltd.) as an organic thermal decomposition type foaming agent 10 parts, terpene phenolic resin as a tackifier resin (trade name: NIR)
10 parts of EZ V-2040, manufactured by Arizona Chemical Co., Ltd. and silicone oil as a foam stabilizer (trade name: TE)
GOSTABB8404, manufactured by Goldschmidt) 1
Parts were blended to prepare solution B. According to the following test methods, viscosity, expansion ratio, adhesion strength (room temperature and 100 ° C)
And the waterproofness was measured. [Viscosity] The viscosities of the above liquids A and B were measured using a Brookfield HB viscometer at a temperature of 25 ° C. and a rotation speed of 50 rpm, and the results are shown in Table 1. [Expansion ratio] The liquid A and the liquid B obtained above are mixed at room temperature to prepare a foaming-type sealing composition (1-1), and its constant weight (g) is measured at 120 ° C for 5 minutes. The foaming ratio of the foaming type sealing composition (1-1) was calculated by the following formula, and the results are shown in Table 1.

Expansion ratio = volume increase before and after foaming / weight of foam-type sealing composition [Adhesion strength] The foam-type sealing composition (1-1)
Prepared test plates (aluminum plate (Al plate), mild steel plate (SPCC plate), fiber reinforced plastic plate (FRP)
Board), a polycarbonate board (PC board), an acrylic painted board, and a gypsum board) to apply a bead having a width of about 3 mm. Each test plate coated with the composition was left in a thermostat at 120 ° C. for 5 minutes to foam and cure, and then left at room temperature for 24 hours. Then, the adhesion strength of the beads on each test plate was measured in an atmosphere at room temperature and in an atmosphere at 100 ° C. This measurement was performed using an Autograph AG-2000.
E (manufactured by Shimadzu Corporation) with a crosshead speed of 50
The measurement was performed at 0 mm / min. The results are shown in Table 2. [Waterproofness] The foam-type sealing composition (1-1) was applied with a release paper 1 mm bead, and the foamed specimen was placed in a U-shape on a gypsum board, and an acrylic plate was overlaid thereon. A pressure was applied to the acrylic plate to adjust the lap compression to 50%, and a test piece kept at 80 ° C. for 60 hours was taken out, and then water tightness was measured. For water tightness, a certain amount of water was put in the U-shaped portion, left at 23 ° C. for 24 hours, and the degree of water leakage was observed. Table 2 shows the results. (Examples 1-2 to 1-3) In the same manner as in Example 1-1, except that the compositions of the solution A and the solution B were changed to the compositions shown in Table 1,
Foaming sealing compositions (1-2) to (1-3) were prepared, and the same measurements and calculations as in Example 1-1 were performed. The results are shown in Tables 1 and 2. (Example 1-4) A foamable sealing composition (1-4) was prepared in the same manner as in Example 1-1, except that the compositions of the solution A and the solution B were changed to the compositions shown in Table 1. . The carbon black used as the conductor was Toka Black # 4500 manufactured by Tokai Carbon Co., Ltd. The same measurements and calculations were performed as in Example 1-1, and the results are shown in Tables 1 and 2.
However, foaming of the foaming type sealing composition (1-4),
Curing was performed using a high-frequency heating device (manufactured by Yamamoto Vinita). (Example 1-5) The foaming-type sealing composition (1-1) prepared in Example 1-1 was foamed and cured under the same conditions as in Example 1-4, and the same as in Example 1-1. Was measured and calculated, and the results are shown in Table 2. (Comparative Example 1-1) A comparative composition (1-1) was prepared in the same manner as in Example 1-1 except that the organic thermal decomposition type foaming agent was not blended with the solution B. The same measurements and calculations were made as in the above, and the results are shown in Tables 1 and 2.

This comparative composition (1-1) does not contain a foaming agent and therefore does not foam, and cannot be used for sealing purposes.

[0049]

[Table 1]

[0050]

[Table 2]

As can be seen from Tables 1 and 2, the foam-type sealing composition according to the present invention has an appropriate viscosity at room temperature, a sufficient adhesive strength at room temperature and under heating, and a high waterproofness. Was. (Example 2-1) Bisphenol A diglycidyl ether as an epoxy resin (trade name: Epikote 828,
Yuka Shell Epoxy, epoxy equivalent: 184-19
4, molecular weight: 380, viscosity: 12,000-15,000
0 cps / 25 ° C.) 50 parts, hydroxyapatite (trade name: HAP BC, 325 mesh pass, manufactured by Nitta Gelatin Co., Ltd.) as an adhesion improver 7.5 parts, di-n-butyltin-based catalyst as a silanol condensation catalyst ( Product name: N
o. 918, manufactured by Sankyoki Gosei Co., Ltd., 2 parts, and hydrophobic Aerosil as a filler (trade name: Aerosil RY-20)
0, manufactured by Nippon Aerosil Co., Ltd., and 2-ethylhexanoic acid (reagent 1 manufactured by Wako Pure Chemical Industries, Ltd.) as a carboxylic acid compound for stabilizing a di-n-butyltin-based catalyst
Grade) 1 part was further added to obtain solution A. Next, 100 parts of a modified silicone oligomer (trade name: SAT-200, manufactured by Kaneka Corporation) as a rubbery organic polymer, and N-β- (aminoethyl) as a silane coupling agent
-Γ-aminopropyltrimethoxysilane (trade name: A
1122, manufactured by Nippon Unicar Co., Ltd.), 1 part, 2,4,6-tris (dimethylaminomethyl) phenol (trade name: Sumicure D, manufactured by Kayaku Akzo) as an epoxy resin curing agent, 5 parts, as a filler Hydrophobic Aerosil (Product name:
2 parts of Aerosil RY-200 (manufactured by Nippon Aerosil Co., Ltd.) and an organic pyrolysis type foaming agent (trade name: Neocervone N #)
5000 parts, manufactured by Eiwa Kasei Kogyo Co., Ltd.) to prepare a B solution.

The viscosities of Liquid A and Liquid B were measured in the same manner as in Example 1-1, and the results are shown in Table 3. A obtained above
The foaming-type sealing composition (2-1) was prepared from the liquid and the liquid B, and the same measurement and calculation as in Example 1-1 were performed. The results are shown in Tables 3 and 4. (Examples 2-2 to 2-3) In the same manner as in Example 2-1 except that the compositions of the solution A and the solution B were changed to the compositions shown in Table 3,
Liquid A and liquid B were prepared, and their viscosities were measured in the same manner as in Example 1-1. Using these, foam-type sealing compositions (2-2) to (2-3) were prepared. The same measurements and calculations as in Example 1-1 were performed, and the results are shown in Tables 3 and 4. (Example 2-4) A foam-type sealing composition (2-4) was prepared in the same manner as in Example 2-1 except that the compositions of the solution A and the solution B were changed to the compositions shown in Table 3. . The carbon black used as the conductor was the same as in Example 1-4. The same measurement and calculation as in Example 1-1 were performed.
The results are shown in Tables 3 and 4. However, the foaming and curing conditions of the foam-type sealing composition (2-4) were the same as in Example 1.
Same as -4. (Example 2-5) The foaming-type sealing composition (2-1) prepared in Example 2-1 was foamed and cured under the same conditions as in Example 2-4, and the same as in Example 1-1. Was measured and calculated, and the results are shown in Table 4. (Comparative Example 2-1) Liquid A and liquid B were prepared in the same manner as in Example 2-1 except that the organic thermal decomposition type foaming agent was not blended with liquid B, and the viscosity thereof was measured in Example 1 The measurement was carried out in the same manner as in Example 1.
-1) was prepared, and the same measurement and calculation as in Example 1-1 were performed. The results are shown in Tables 3 and 4.

Since this comparative composition (2-1) does not contain a foaming agent, it does not foam and cannot be used for sealing purposes. (Comparative Example 2-2) A commercially available polyurethane-based foam-type sealing material (ether-based urethane prepolymer-based sealing material, expansion ratio: 3 times) as a comparative composition (2-2) was the same as in Example 1-1. Measurements and calculations were performed, and the results are shown in Tables 3 and 4. (Comparative Example 2-3) Example of a commercially available hot-melt foam type sealing material (trade name: Nittite H-6636, manufactured by Nitta Gelatin Co., 3 times expansion ratio) as a comparative composition (2-3) The same measurement and calculation as in 1-1 were performed, and the results are shown in Tables 3 and 4. The melt viscosity was measured using a Brookfield type thermocell system viscometer No. 27.

[0054]

[Table 3]

[0055]

[Table 4]

As can be seen from Tables 3 and 4, the foam-type sealing composition according to the present invention has an appropriate viscosity at room temperature, a sufficient adhesive strength at room temperature and under heating, and a high waterproofness. Was. On the other hand, both the comparative composition (2-2) and the comparative composition (2-3) have undergone interfacial destruction, and have poor adhesion strength and low waterproofness.

[0057]

The foam-type sealing composition according to the present invention has an appropriate viscosity for coating, has heat resistance, and has a sufficient expansion ratio without using chlorofluorocarbon. In addition, the foaming ratio is stable, and it has sufficient adhesiveness at normal temperature and high temperature, and has high waterproofness.

The method of using the foam-type sealing composition according to the present invention can easily obtain a foam-type sealing.

[Brief description of the drawings]

FIG. 1 is a perspective view of an architectural outer wall material obtained by using the foam-type sealing composition of the present invention.

FIG. 2 is a cross-sectional view of the vicinity of a window glass molding of an automobile obtained by using the foam-type sealing composition of the present invention.

FIG. 3 is a cross-sectional view near a seal of a refrigerator obtained by using the foam-type sealing composition of the present invention.

FIG. 4 is a cross-sectional view of a can lid with packing obtained by using the foamable sealing composition of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Building exterior wall material 2 Exterior wall material main body 3a Lap joint part 3b Pre-sealing part 4 Mall 5 Window glass 6 Body 7 Adhesive layer 8 Dam rubber 9 Seal 10 Inner box 11 Outer box 12 Can lid with packing 13 Can lid body 14 Packing

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor, Mutsuo Matsumoto 2-22 Futama, Yao-shi, Osaka Nitta Gerachin Co., Ltd. Osaka Plant

Claims (8)

[Claims] 1. A foaming method comprising: a rubbery organic polymer containing at least one reactive silicon group; a silanol condensation catalyst for curing said rubbery organic polymer; and an organic pyrolytic foaming agent. Composition for mold sealing. 2. The foam-type sealing composition according to claim 1, further comprising an epoxy resin having two or more oxirane rings in one molecule, and an epoxy resin curing catalyst for curing the epoxy resin. 3. The foam-type sealing composition according to claim 1, further comprising a silane coupling agent. 4. The foam-type sealing composition according to claim 1, further comprising a tackifier resin. 5. The foam-type sealing composition according to claim 1, further comprising a conductor that generates heat by induction heating. 6. The foamable sealing composition according to claim 1, which is a sealing material. 7. A method of using the foamable sealing composition according to claim 1 wherein the foamable sealing composition is foamed by heating. 8. The method of using the foam-type sealing composition according to claim 7, wherein the heating is performed by high-frequency heating.