JP3093964B2 - Composite of silicone rubber and silicone-epoxy resin and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrally molded product of a silicone-epoxy resin and a silicone rubber, and a method for producing the same. In particular, the present invention relates to an integrally molded composite useful in the fields of electricity, electronics, OA equipment, automobiles, precision equipment, and the like, and a method for producing the composite.

[0002]

2. Description of the Related Art Hitherto, many methods have been proposed for bonding a silicone rubber and an organic resin. For example, a method has been proposed in which a primer is applied to the surface of a molding resin, and an uncured silicone rubber is applied and cured on the surface, followed by adhesion, and a method in which a self-adhesive silicone rubber material is cured from above the molding resin. This self-adhesive silicone rubber material (composition)
In particular, a large number of inventions have been filed in which the adhesive component is the essence. In addition, hydrogen atoms directly bonded to silicon atoms on the organic resin side are 30 mol% with respect to silicon atoms in one molecule.
A method in which the organopolysiloxane contained above is added and adhered to an addition-curable silicone rubber (see Japanese Patent Publication No. 2-34311), and a method of physically fitting the silicone rubber to an organic resin (Japanese Patent Publication No. 63-45292). Japanese Patent Application Laid-Open No. 63-183843), and a method of bonding and integrating silicone rubber to an olefin resin grafted with a compound having an aliphatic unsaturated group and a silicon-bonded hydrolyzable group. ing.

[0003]

However, in the method of bonding using a primer, it takes time and effort to take out a molded resin product from a mold or the like and apply the primer. The method of applying self-adhesive silicone to a resin molded article and curing it has a great difficulty in that when a resin or silicone rubber is molded using a mold or the like, the silicone rubber itself adheres to the mold. In addition, the method of adding an organopolysiloxane containing a hydrogen atom directly bonded to a silicon atom to a resin may cause a change in the physical properties of the resin itself due to the addition of the siloxane, making it difficult to obtain the original characteristics. there were. Also, in the method of integrating by physical fitting, there is a concern that the fitting may be released by physical force. On the other hand, in recent years, silicone rubber has been recognized for its high reliability in heat resistance, weather resistance, electric characteristics, and the like, and its use is expanding in fields such as electric, electronic, OA equipment, and automobiles. Thus, there has been a demand for the supply of an integrally molded product having a high quality and a stable quality. The present invention is intended to solve such a problem and to provide an integrally molded composite having a thermosetting resin and a silicone rubber firmly bonded to each other and having a stable quality, and a method for easily producing the composite. It was done as.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, an organic peroxide-curable or addition-curable organopolysiloxane composition as a silicone rubber and a silicone resin as a resin. The present inventors have found that by selecting a polymer blend system with an epoxy resin, it is possible to obtain an integrally molded composite having an adhesive force that can withstand practical use in a simple and short time, and reached the present invention.
The composite of the present invention and a method for producing the same have solved the above-mentioned problems, and the composite comprises a cured product of an organic peroxide-curable or addition-curable silicone rubber composition and a curable silicone-
The cured product of the epoxy resin composition is directly bonded and integrated at the time of curing, and the method for producing the composite is an organic peroxide-curable or addition-curable silicone rubber composition, or a curable silicone-epoxy resin. After one of the compositions is cured at room temperature or under heating, the other is adhered and cured at room temperature or under heating.

Hereinafter, the present invention will be described in more detail. The organic peroxide-curable silicone rubber composition which can be used in the present invention includes: A) an organopolysiloxane containing preferably at least two lower alkenyl groups in one molecule, and B) a catalytic amount of an organic peroxide. Is a liquid or paste-like composition at room temperature, which is a main component, and hardens when left or heated at room temperature to become a rubber-like elastic body.

The organopolysiloxane of the component A) has a viscosity of 100 cP to 10,000,000 cP, preferably 1,000 cP to 1,000,000 cP at room temperature (for example, 25 ° C.)
The one represented by the general composition formula R _a SiO _{(4-a) / 2} is used.
R is a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a hexyl group, a cyclohexyl group, an octyl group, an alkyl group such as a decyl group, a vinyl group, an allyl group, a propenyl group, Aryl groups such as alkenyl groups such as isopropenyl group, butenyl group, isobutenyl group, hexenyl group, cyclohexenyl group, phenyl group, tolyl group, xylyl group, and naphthyl group, and aralkyl groups such as benzyl group, phenylethyl group, and phenylpropyl group. Group, a chloromethyl group, a chloropropyl group, a bromoethyl group, a halogen-substituted hydrocarbon group such as 3,3,3-trifluoropropyl group, a cyano group-substituted hydrocarbon group such as a cyanoethyl group, and the like; It is preferably selected from unsubstituted or substituted monovalent hydrocarbon groups having 1 to 8 carbon atoms. May be made, preferably contains an average of at least two alkenyl groups in a molecule to improve crosslinking, more preferably contains the group at a molecular chain terminal. In order to obtain a rubber elastic body, a is in the range of 1.9 to 2.2, preferably 1.95 to 2.1, and even if this organopolysiloxane is linear,
It may be branched containing RSiO _3/2 units or SiO _4/2 units, but usually, the main chain portion basically consists of repeating R ₂ SiO _2/2 units, and the molecular chain terminal is R Generally, it has a linear structure blocked by ₃ SiO _1/2 units. The group bonded to the silicon atom may be basically any of the above, but the alkenyl group is preferably a vinyl group, and the other groups are preferably a methyl group and a phenyl group. This organopolysiloxane can be obtained by a known method, that is, by performing an equilibration reaction between an organocyclopolysiloxane and a hexaorganodisiloxane in the presence of an alkali or acid catalyst.

The organic peroxide of the component (B) is used as a catalyst for accelerating the crosslinking reaction of the component (A), for example, benzoyl peroxide, o-monochlorobenzoyl peroxide, bis-2,4. -Dichlorobenzoyl peroxide, dicumyl peroxide,
t-butylperoxybenzoate, di-t-butyl peroxide, p-monochlorobenzoyl peroxide, t-butylcumyl peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane , 2,5-dimethyl-2,5-bis (t-
Butylperoxy) hexane, 1,6-bis (t-butylperoxycarboxy) hexane, and the like.
It is not limited to these. The amount of the component (B) to be added may be appropriately selected according to the desired curing rate, and is usually 0.1 to 100 parts (parts by weight, hereinafter the same) of the component (A).
The amount may be in the range of 10 parts, preferably 0.2 to 2 parts.

[0008] A filler may be added to the components A) and B) in order to control the fluidity and to improve the mechanical strength of the molded product. Such fillers include precipitated silica, fumed silica, calcined silica, reinforcing fillers such as fumed titanium oxide, ground quartz, diatomaceous earth, asbestos, aluminosilicate, iron oxide, zinc oxide and calcium carbonate. Such non-reinforcing fillers are exemplified, and those which have been surface-treated with an organic silicon compound such as hexamethyldisilazane, trimethylchlorosilane or polymethylsiloxane may be used as they are. In addition, a pigment, a heat resistance improver, a flame retardant, a plasticizer, and the like may be added as needed.

Examples of the addition-curable silicone rubber composition include: C) an organopolysiloxane containing at least two lower alkenyl groups on average per molecule, D) an organohydrogenpolysiloxane liquid at room temperature, and E) an addition reaction. There is a liquid or paste-like composition containing a catalyst as a main component at room temperature, and when left or heated at room temperature, it cures to a rubber-like elastic body.

The alkenyl group-containing organopolysiloxane of component (C) may be used at room temperature (for example, 25 ° C.) at a pressure of 100 cP.
Those having a viscosity of about 1,000,000 cP, preferably about 1,000 cP to 300,000 cP and represented by the general composition formula R ¹ _b SiO _{(4-b) / 2} are used. R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, similar to those exemplified for R in the above component A), such as a methyl group and an ethyl group. Alkyl groups such as a propyl group, an alkenyl group such as a vinyl group, an allyl group, a propenyl group and a butenyl group; an aryl group such as a phenyl group, a tolyl group and a xylyl group; an aralkyl group such as a benzyl group; A halogen-substituted hydrocarbon group such as -trifluoropropyl group; a cyano group-substituted hydrocarbon group such as a cyanoethyl group; Each group in one molecule may be the same or different, but in order to have crosslinkability, it is necessary that at least two alkenyl groups are contained in one molecule on average, and it is preferable that the alkenyl group is contained at the terminal of the molecular chain. You. B to indicate rubber elasticity
1.8 to 2.4, preferably 1.9 to 2.2, and the organopolysiloxane may be linear or branched containing R ¹ SiO _3/2 units or SiO _4/2 units. usually is basically the main chain consists repetition of R ¹ ₂ SiO _2/2 units, linear molecular chain terminals blocked with R ¹ ₃ SiO _1/2 units chain diorganopolysiloxane It is common. The group bonded to the silicon atom may be basically any of the above, but the alkenyl group is preferably a vinyl group, and the other groups are preferably a methyl group and a phenyl group. This organopolysiloxane can be produced by a known method.

The organohydrogenpolysiloxane of the component D) has an average of at least two, preferably at least three, hydrogen atoms bonded to silicon atoms (ie, S atoms) in one molecule.
iH group) is used, and this SiH group acts as a crosslinking agent by performing an addition reaction with the alkenyl group of the component C) in the presence of the component E) described later. There is no limitation, and various types of conventionally manufactured, for example, linear, branched, cyclic, and three-dimensional network structures are used. Specifically, those represented by the following general formula can be suitably used. R ² _c H _d SiO _{(4-cd) / 2} wherein R ² has 1 to 12 carbon atoms similar to those exemplified for R in component A), and preferably has no carbon atoms containing an aliphatic unsaturated bond. 1 to 8 unsubstituted or substituted monovalent hydrocarbon groups, such as alkyl groups such as methyl group, ethyl group and propyl group, aryl groups such as phenyl group and tolyl group, cycloalkyl groups such as cyclohexyl group, and benzyl group And substituted alkyl groups such as a 3,3,3-trifluoropropyl group. Also, the nature of this thing,
From the viewpoints of reactivity, characteristics of the cured product, etc., c, d, and c + d are respectively 0.8 ≦ c ≦ 2.1, preferably 1.2 <c ≦ 2.0, 0.002.
≦ d ≦ 1, preferably 0.01 ≦ d ≦ 1, 1 ≦ c + d ≦ 3,
Preferably, the number satisfies 1.5 ≦ c + d ≦ 2.7, and the viscosity of the organohydrogenpolysiloxane at 25 ° C. is preferably 1 to 1,000 cP, particularly preferably about 5 to 200 cP.

Examples of the organohydrogenpolysiloxane include methylhydrogenpolysiloxane having trimethylsiloxy groups at both ends, a dimethylsiloxane / methylhydrogensiloxane unit copolymer having trimethylsiloxy groups at both ends, and dimethylhydrogensiloxy at both ends. Group-blocked dimethylpolysiloxane, dimethylsiloxane-methylhydrogensiloxane unit copolymer with dimethylhydrogensiloxy groups at both ends, methylhydrogensiloxane-diphenylsiloxane unit copolymer with trimethylsiloxy groups at both ends, trimethyl at both ends A siloxy group-blocked methyl hydrogen siloxane / diphenyl siloxane / dimethyl siloxane unit copolymer, a copolymer composed of (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 units, (CH ₃ ) Copolymers composed of ₂ HSiO _1/2 units, SiO _4/2 units, and (C ₆ H ₅ ) SiO _3/2 units are exemplified. The amount of the organohydrogenpolysiloxane is preferably from 0.1 to 30 parts, more preferably from 0.3 to 10 parts, per 100 parts of the organopolysiloxane of the component (C) in view of the properties of the cured product. The compounding amount is 0.2 to 10 mol / mol in a molar ratio of a hydrogen atom (SiH group) bonded to a silicon atom in the component D) to an alkenyl group in the component C).
Preferably, the amount may be 0.5 to 5 mol / mol.

The catalysts for the addition reaction of component E) include platinum black, platinum (II) chloride, chloroplatinic acid, a reaction product of chloroplatinic acid with a monohydric alcohol, a complex of chloroplatinic acid with olefins, platinum bisacetate. Examples thereof include platinum group metal compounds such as acetate, palladium-based catalyst, and rhodium-based catalyst.
The compounding amount of the addition reaction catalyst can be a catalytic amount, but usually, the C) component,
D) 0.1 to 1,000 ppm, preferably 1 to the total of the components
It is set to about 500 ppm.

A filler may be added to the components C), D) and E) in order to adjust the fluidity or to improve the mechanical strength of the molded product. Such fillers include precipitated silica, fumed silica, calcined silica, reinforcing fillers such as fumed titanium oxide, ground quartz, diatomaceous earth,
Non-reinforcing fillers such as asbestos, aluminosilicate, iron oxide, zinc oxide, and calcium carbonate are exemplified, and those that have been surface-treated with an organosilicon compound such as hexamethyldisilazane, trimethylchlorosilane, and polymethylsiloxane are used as they are. May be. In addition, a pigment, a heat resistance improver, a flame retardant, a plasticizer, and the like may be added as needed.

On the other hand, the curable silicone-epoxy resin composition (b) used in the present invention is not particularly limited as long as it has curability and can form a uniform cured product. It is. That is, 1) 100 parts of a curable epoxy resin (parts by weight, the same applies hereinafter) , 2) 5 to 500 parts of an organopolysiloxane containing at least two lower alkenyl groups in one molecule, 3) at least one part in one molecule. Having a hydrogen atom bonded to two silicon atoms and having the general formula R ⁴ _f H _g SiO _{(4-fg) / 2} (wherein R ⁴ may be the same or different, and the number of carbon atoms Represents an unsubstituted or substituted monovalent hydrocarbon group containing 1 to 12 aliphatic unsaturated bonds, f represents 1 ≦ f ≦ 2.4, and g represents 0 <g ≦ 1. 1 to 50 parts with respect to 100 parts by weight of the second component of genpolysiloxane 4) 0.1 to 10 parts of an organosilicon compound having at least one silanol group in one molecule, 5) 0.001 to 10 parts of an organoaluminum compound and 6 ) Platinum group compound Second component as platinum group metal 1,000,000 parts Composition consisting of 0.1 to 500 parts is preferred.

The curable epoxy resin of the first component may be any one as long as it is usually used in a curable epoxy resin composition, and specific examples thereof include bisphenol A
Epoxy resin, bisphenol F epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, alicyclic epoxy resin, epoxy resin containing heterocycle such as triglycidyl isocyanate and hydantoin epoxy, hydrogenated bisphenol A epoxy Resin, aliphatic epoxy resin such as propylene glycol diglycidyl ether and pentaerythritol polyglycidyl ether, epoxy resin obtained by reaction of aromatic, aliphatic or alicyclic carboxylic acid with epichlorohydrin, containing spiro ring Epoxy resin, o-
A glycidyl ether type epoxy resin which is a reaction product of an allylphenol novolak compound and epichlorohydrin, a reaction product of a diallyl bisphenol compound having an allyl group at an ortho position of each hydroxyl group of bisphenol A and epichlorohydrin Certain glycidyl ether type epoxy resins and the like can be mentioned.

The organopolysiloxane having an average of at least two lower alkenyl groups in one molecule of the second component is 100 cP to 1,000,000 cP at room temperature (for example, 25 ° C.).
Preferably, those having a viscosity of about 1,000 cP to 300,000 cP and having essentially no silanol group in the molecule represented by the general composition formula R ³ _e SiO _{(4-e) / 2} are used. R ³
Is R in component A) of the silicone rubber composition described above.
Examples thereof include unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group, and a hexyl group. An alkenyl group such as an alkyl group such as a cyclohexyl group, a vinyl group, an allyl group, a propenyl group or a butenyl group; an aryl group such as a phenyl group, a tolyl group and a xylyl group; an aralkyl group such as a benzyl group; Examples include a halogen-substituted hydrocarbon group such as a trifluoropropyl group, and a cyano-substituted hydrocarbon group such as a cyanoethyl group. Each group in one molecule may be the same or different, but in order to have cross-linking property, it is supposed that at least two alkenyl groups are included in one molecule on average, and preferably at both ends of the molecular chain. . E is from 1.8 to 2.
The organopolysiloxane is a linear or branched resin containing R ³ SiO _3/2 units or SiO _4/2 units, or a resin material having a three-dimensional network structure. may be, but typically, essentially the main chain consists of the repetition of R ³ ₂ SiO _2/2 units, the molecular chain terminals di R ³ ₃ SiO _1/2 are blocked with units linear It is generally an organopolysiloxane. The group bonded to the silicon atom may be basically any of the above, but is preferably a vinyl group as the alkenyl group, a methyl group as the other group, or a compound which improves the compatibility with the epoxy resin. From the viewpoint, a phenyl group is desirable. The organopolysiloxane of the second component essentially does not contain a silanol group in the molecule. This organopolysiloxane can be produced by a known method. If the amount of the second component is less than 5 parts per 100 parts of the curable epoxy resin as the first component, when the obtained silicone-epoxy resin composition is cured, the heat resistance characteristic of the silicone resin is obtained. If the compounding amount is more than 500 parts, sufficient strength cannot be obtained in the cured product, so that the amount is 5 to 500 parts, preferably 20 to 200 parts. You.

The organohydrogenpolysiloxane of the third component has at least one hydrogen atom bonded to one silicon atom (ie, SiH group) in one molecule, and has at least one, preferably one, hydrogen atom contained in one molecule. Two or more SiH groups undergo an addition reaction with an alkenyl group in the second component in the presence of a catalyst to extend or crosslink the chain length, and have a general composition formula of R ⁴ _f H _g SiO _{(4-fg) / 2} (wherein R ⁴ may be the same or different from each other, and is an unsubstituted or substituted monovalent hydrocarbon having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, which does not contain an aliphatic unsaturated bond. Represents a group,
f is 1 ≦ f ≦ 2.4, preferably 1.6 ≦ f ≦ 2, and g is 0 <
g ≦ 1, preferably 0.002 ≦ g ≦ 1, f + g preferably represents a number satisfying 1.6 <f + g ≦ 3). From the properties, reactivity, properties of the cured product, etc., f and g are within the above ranges, but the reason that R ⁴ does not contain aliphatic unsaturated bonds is that R ⁴ does not contain aliphatic unsaturated bonds in the molecule.
This is because the addition reaction with the iH group is not preferable. This organohydrogenpolysiloxane is linear, branched,
The organohydrogenpolysiloxane may be any resinous material having a cyclic or three-dimensional network structure, and the viscosity at 25 ° C. of the organohydrogenpolysiloxane is preferably from 1 to 1,000 cP, particularly preferably from about 5 to 200 cP. The number of hydrogen atoms bonded to silicon atoms per molecule of the organohydrogenpolysiloxane is 1 from the viewpoint of the strength of the cured product.
The number is preferably 1 to 200, particularly preferably about 2 to 20 in the molecule. The third component does not essentially contain a silanol group in the molecule. This component can be produced by a known method.

As R ⁴ in the above formula, there can be mentioned the same ones except for the alkenyl group from those exemplified as R in component A) of the above silicone rubber composition. Examples thereof include a methyl group, an ethyl group and a propyl group. Group, butyl group, hexyl group, octyl group, decyl group, undecyl group, alkyl group such as dodecyl group, cyclohexyl group,
Cycloalkyl group such as cyclooctyl group, phenyl group,
Aryl groups such as naphthyl group, methylphenyl group and xylyl group; aralkyl groups such as benzyl group, phenylethyl group and cumyl group; or part or all of the hydrogen atoms bonded to carbon atoms of these groups are halogen atoms. Substituted groups,
For example, chloromethyl group, p-chlorophenyl group, m-
Γ substituted with a chlorophenyl group, an o-chlorophenyl group, a p-trifluoromethylphenyl group, an o-trifluoromethylphenyl group, a 3,3,3-trifluoropropyl group, a cyanoethyl group, a trimethylsilyl group or a trialkoxysilyl group. -Trimethylsilylpropyl group, γ-trimethoxysilylpropyl group, γ-triethoxysilylpropyl group, γ-glycidoxypropyl group substituted with an epoxy group, β- (3,4-epoxycyclohexyl) ethyl group and the like. You. The amount of the third component is 1 to 50 parts, preferably 5 to 100 parts of the second component.
When the amount is less than 1 part, the cross-linking property as a function of this component is insufficient, and
If the amount exceeds the range, the amount of the crosslinking agent is too large, and in any case, the strength of the cured product may not be obtained. Also,
The compounding amount is 0.2 to 10 mol / mol, preferably 0.5 to 5 mol / mol, in terms of a molar ratio of a hydrogen atom (SiH group) directly bonded to a silicon atom in the third component to an alkenyl group in the second component. It may be.

As the organosilicon compound having at least one silanol group in one molecule of the fourth component, an organohydroxysilane or an organohydroxy (poly) siloxane is used. The organohydroxysilane is represented by the general formula R ⁵ _h Si (OH) _4-h (h is 1, 2 or 3), wherein R ⁵ may be the same or different, and may have 1 to 12 carbon atoms. It preferably represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms which does not contain an aliphatic unsaturated bond, and examples thereof include the same as those exemplified as R in the component A) of the silicone rubber. For example, methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group, undecyl group, alkyl group such as dodecyl group, cyclohexyl group, cycloalkyl group such as cyclooctyl group, vinyl group , Allyl group, alkenyl group such as propenyl group, phenyl group, naphthyl group, aryl group such as methylphenyl group, xylyl group, benzyl group, phenylethyl group, aralkyl group such as cumyl group, Or a group in which part or all of the hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, for example, chloromethyl group, p-chlorophenyl group, m-chlorophenyl group, o-chlorophenyl group, p-triphenyl group. Fluoromethylphenyl group, o-trifluoromethylphenyl group, 3,
Examples thereof include a 3,3-trifluoropropyl group and a cyanoethyl group.

The organohydroxy (poly) siloxane has a general composition formula: R ⁶ _i (HO) _j SiO _{(4-ij) / 2} (where R ⁶ may be the same or different, 1 to 12, preferably an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms not containing an aliphatic unsaturated bond, i is 1 ≦ i ≦ 2.5, preferably 1.5 ≦ i ≦ 2.2 , J
Is 0 <j ≦ 2, preferably 0.05 ≦ j ≦ 2, especially 0.1 ≦ j
≦ 1.5, and 1 <i + j ≦ 3, preferably 1.6 ≦ i +
j represents a number that satisfies j ≦ 2.5).
From the properties, reactivity, characteristics of the cured product, etc., i, j
Is within the above range, but the organopolysiloxane may be any of linear, branched, cyclic, and three-dimensional network resinous materials. Examples of R ⁶ include the same ones as those exemplified as R in the component A) of the silicone rubber, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a decyl group, Undecyl group, alkyl group such as dodecyl group, cycloalkyl group such as cyclohexyl group and cyclooctyl group, alkenyl group such as vinyl group, allyl group and propenyl group, aryl group such as phenyl group, naphthyl group, methylphenyl group and xylyl group Groups, benzyl groups, phenylethyl groups, aralkyl groups such as cumyl groups, or groups in which part or all of the hydrogen atoms bonded to carbon atoms of these groups have been substituted with halogen atoms, for example, chloromethyl group, p- Chlorophenyl group, m-chlorophenyl group, o
-Chlorophenyl group, p-trifluoromethylphenyl group, o-trifluoromethylphenyl group, 3,3,3-
Γ-glycidyl substituted with a trifluoropropyl group, a cyanoethyl group, a γ-trimethylsilylpropyl group substituted with a trimethylsilyl group or a trialkoxysilyl group, a γ-trimethoxysilylpropyl group, a γ-triethoxysilylpropyl group, or an epoxy group Examples include a xypropyl group and a β- (3,4-epoxycyclohexyl) ethyl group.

In the organohydroxysilane or organohydroxy (poly) siloxane compound,
If the content of the silanol group is too small, sufficient cross-linking with the epoxy resin cannot be performed, and not only the required strength cannot be obtained, but also the curing reaction itself will be extremely slow. Conversely, if the content of the silanol group is too large, the silicone compound becomes unstable. Such an organohydroxysilane or organohydroxy (poly) siloxane can be produced by a known method. For the latter, for example, vinylmethyldichlorosilane and phenyltrichlorosilane may be used, if necessary, with one or more selected from tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, diphenyldichlorosilane, and methylphenyldichlorosilane. Co-hydrolysis of the added mixture, one or two selected from tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, diphenyldichlorosilane, methylphenyldichlorosilane as required for vinyldimethylchlorosilane and phenyltrichlorosilane Co-hydrolysis of the mixture,
Methoxysilanes corresponding to the respective chlorosilanes exemplified above can be obtained by co-hydrolysis of a mixture of alkoxysilanes such as ethoxysilane in the presence of an alkali or acid catalyst, among which trifunctional silane and An organopolysiloxane resin or an organopolysiloxane resin intermediate obtained by co-hydrolyzing a silane mixture containing a tetrafunctional silane is preferred.

The content of the silanol group can be adjusted by the concentration of the catalyst, the reaction temperature, and the like. Further, in the next step, the generated silanol group is treated with a silylating agent such as trimethylchlorosilane, hexamethyldisilazane or divinyltetramethyldisilazane. Denaturation is also possible. If the amount of the fourth component is too small with respect to 100 parts of the curable epoxy resin as the first component, the curing of the epoxy resin will be insufficient, and if it is too large, it will be uneconomical. Instead, it may reduce the physical properties of the cured product,
0.1 to 10 parts, preferably 1 to 5 parts.

The organoaluminum compound of the fifth component includes an alkyl group, an unsubstituted or substituted phenyl group, a haloalkyl group, an alkoxy group, an unsubstituted or substituted phenoxy group, an acyloxy group, a β-diketonato group, an o-carbonylphenolate group and the like. Is a compound in which an organic group selected from the group is bonded or coordinated to an aluminum atom. In the organic group, as the alkyl group, a methyl group, an ethyl group, an n-propyl group,
Isopropyl group, n-butyl group, sec-butyl group, t
-Butyl group, n-pentyl group, and the like. Examples of the unsubstituted or substituted phenyl group include a phenyl group, a p-methoxyphenyl group, an o-methoxyphenyl group, and a p-ethoxyphenyl group. Group, chloroethyl group, chloropropyl group are exemplified,
Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, a butoxy group, and a pentoxy group. Examples of the unsubstituted or substituted phenoxy group include a phenoxy group and o.
-Methylphenoxy group, o-methoxyphenoxy group, o
-Nitrophenoxy group, 2,6-dimethylphenoxy group, and examples of the acyloxy group include an acetato group, a propionate group, an isopropionate group, a butyrate group, a stearat group, an ethylacetoacetato group, a propylacetoacetato group, and butylacetoacetate. Acetato group, diethyl malato group,
A dipivaloyl methanato group is exemplified, and as the β-diketonato group, an acetylacetonato group, a trifluoroacetylacetonato group, a hexafluoroacetylacetonato group,

Embedded image (The above formula is a compound before coordination), and the o-carbonylphenolate group is a salicylaldehyde group.

Specific examples of aluminum compounds include trimethoxyaluminum, triethoxyaluminum, triisopropoxyaluminum, triphenoxyaluminum, tri (p-methylphenoxy) aluminum, isopropoxydiethoxyaluminum, tributoxyaluminum, triacetoxyaluminum, Aluminum tristearate, aluminum tributyrat, aluminum tripropionate, aluminum triisopropionate, aluminum tris (acetylacetonato),
Tris (trifluoroacetylacetonato) aluminum, tris (salicylaldehyde) aluminum, tris (pentafluoroacetylacetonato) aluminum, tris (ethylacetato) aluminum, ethylacetatodiisopropoxyaluminum, tris (diethylmalorato) aluminum, Tris (propylacetoacetato) aluminum, tris (butylacetoacetato) aluminum, tris (isopropylacetoacetato) aluminum, tris (dipivaloylmethanato) aluminum, diacetylacetonatodipivaloylmethanatoaluminum, ethylacetoa Acetatodiisopropoxy aluminum,

[0026]

Embedded image And the like.

One of these aluminum compounds may be used alone, or two or more thereof may be used in combination. The amount of the aluminum compound added is 0.001 to 10 parts, preferably 100 parts to 100 parts of the epoxy resin.
It is in the range of 0.01 to 5 parts. If the amount is less than 0.001 part, sufficient curing properties cannot be obtained, and if the amount exceeds 10 parts, the cost increases and the physical properties and adhesiveness are adversely affected.

The platinum group compound of the sixth component serves as a catalyst for the addition reaction between the alkenyl group-containing organopolysiloxane of the second component and the organohydrogenpolysiloxane of the third component. Examples thereof include platinum black and platinum chloride. Chloroplatinic acid, a reaction product of chloroplatinic acid and a monohydric alcohol, a complex of chloroplatinic acid and an olefin, platinum bisacetoacetate, a palladium catalyst, a rhodium catalyst, and the like. These are 0.1 to 500 parts, preferably 0.5 part, per million parts of the second component as a metal of platinum, palladium or rhodium.
The addition amount is up to 200 parts. If the amount is less than 0.1 part, sufficient curing cannot be obtained, and if the amount is more than 500 parts, the effect is not further improved, and it is economically disadvantageous.

The first to sixth components described above do not necessarily need to be independent and separate components. For example, the first to sixth components have at least two lower alkenyl groups in one molecule and have at least one silanol. The organopolysiloxane having a group can serve both as the second component and the fourth component. The following are suitable as the curable silicone-epoxy resin composition (c) in this case. That is, 1) 100 parts of a curable epoxy resin, 2 ) a molecule having at least one hydrogen atom bonded to a silicon atom in one molecule, and having a general composition formula R ⁴ _f H _g SiO _{(4-fg) / 2} (wherein , R ⁴ may be the same or different, and represent an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond having 1 to 12 carbon atoms, and f is 1 ≦ f ≦ 2.4; g is 0 <
g represents 1) 1 to 50 parts based on 100 parts of the following third component; 3 ) at least two lower alkenyl groups and at least one silanol group per molecule on average Having the general composition formula
R ⁷ _i (HO) _j SiO _{(4-ij) / 2} (wherein, R ⁷ may be the same or different, and represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms. Represents, of which 2 to 80 mol% is a lower alkenyl group,
i is 1 ≦ i ≦ 2.5, j is 0 <j ≦ 2, i + j is 1 <i +
j represents 3).
5 to 500 parts, 4 ) 0.001 to 10 parts of an organoaluminum compound and 5 ) Platinum group compound A composition comprising 0.1 to 500 parts as a platinum group metal with respect to 1,000,000 parts of the third component is preferable.

The components other than the third component are as described above. In the above general formula, R ⁷ is a monovalent hydrocarbon radical unsubstituted or substituted with 1 to 12 carbon atoms, those this as R ⁷ is the same as those exemplified as R ⁵ or R ⁶ and the it can be cited, as the third component, in the general formula as R ⁷ average of at least two per molecule, and 2 to 80 mol% of the total R ⁷ groups, preferably 2 to 20 mol% In this case, the third component is used in an amount of 5 to 5 parts by weight per 100 parts by weight of the curable epoxy resin of the first component.
500 parts by weight, preferably 20 to 200 parts by weight. Thereby, the object can be achieved. In addition to the first to sixth (5) components, as a filler, fused silica, crystalline silica, glass powder, glass fiber, clay,
Talc, mica, asbestos, zinc oxide, magnesia,
Addition of various fine powders, fibrous materials, and the like such as aluminum silicate, zirconium silicate, alumina, fumed silica, precipitated silica, and the like can be performed without any problem as long as the adhesion to the silicone rubber is not impaired.

In the method for producing a composite of a silicone rubber and a silicone-epoxy resin according to the present invention, first, one of the above-mentioned organic peroxide-curable or addition-curable silicone rubber composition and the silicone-epoxy resin composition is used. One composition is cured and molded at room temperature or by heating. The molding method can be freely selected according to the viscosity of the composition and the like, and may be any of injection molding, compression molding, injection molding, extrusion molding, and transfer molding. After one composition is cured and molded (primary molding), the other composition is brought into close contact with the primary molded article and is cured or molded at room temperature or by heating (secondary molding) to form an integrally molded article having good adhesiveness. Obtained easily. The molding method of this secondary molded product can also be freely selected according to the viscosity of the composition and the like, and injection molding, compression molding, injection molding,
Any of extrusion molding, transfer molding and the like may be used. The timing at which the secondary molded product is cured does not necessarily need to be after the primary molded product has been completely cured, and there is no problem as long as the primary molded product is cured to such an extent that the two are not mixed and an interface can be formed.

[0032]

Next, embodiments of the present invention will be described with reference to examples. In addition, in the following examples, a part shows a weight part and% shows a weight%. The viscosity indicates a value at 25 ° C.

[0033]

【Example】

(Example 1) Epicoat 828 of epoxy resin (trade name, manufactured by Shell Chemical Company, bisphenol A type, epoxy equivalent 190 to 210, molecular weight 380) 100 parts, 10 parts of an epoxy compound represented by the following formula (I), 10 parts of an organopolysiloxane having a viscosity of 4,000 centipoise represented by the formula (II), 2 parts of an organohydrogenpolysiloxane having a viscosity of 25 centipoise represented by the following formula (III), 1.5 parts of diphenylsilanediol, aluminum benzoate
0.6 part and 0.1 part of an isopropanol solution of chloroplatinic acid (platinum content: 0.5%) were added to obtain a silicone-epoxy resin composition (A).

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On the other hand, fumed silica having a specific surface area (according to the BET method; the same applies hereinafter) of 200 m ² / g is added to 100 parts of dimethylpolysiloxane having a viscosity of 10,000 centipoise in which both ends of the molecular chain are blocked with dimethylvinylsiloxy groups. 30 copies,
6 parts of hexamethyldisilazane and 2 parts of water were added and mixed by heating at 150 ° C. for 3 hours. 50 parts of the above-mentioned dimethylvinylsiloxy-blocked dimethylpolysiloxane and a viscosity of 10 centipoise at both ends of a trimethylsilyl-blocked dimethylsiloxane. 0.4 part of a methyl hydrogen siloxane copolymer (50 mol% of a dimethyl siloxane unit, 50 mol% of a methyl hydrogen siloxane unit) and 0.1 part of an isopropanol solution of chloroplatinic acid (a platinum content of 0.5%) were added, and a silicone rubber composition ( B) was obtained.

Next, the silicone-epoxy resin composition (A) is injected into the cavity 2 of the lower mold 1 shown in FIG. 1 by a half amount in the lower mold 1 and heated and cured at 150 ° C. for 3 minutes. After that, the upper mold 3 is placed on the lower mold 1 and the lower mold 1 is closed, and the silicone-epoxy resin composition (A) is put on the silicone-epoxy resin composition (A) through the injection port 4 provided on the upper mold 3. The rubber composition (B) was injected at an injection pressure of 60 kg / cm ² and cured by heating at 150 ° C. for 5 minutes to obtain an integrated product in which the silicone-epoxy resin and the silicone rubber were firmly adhered. After this integrated material was post-cured at 150 ° C. for 3 hours, the hardness of each was measured.
A was 95 or more (that is, the measurement limit or more), and the silicone rubber part was 35 according to JIS A. The JIS A hardness was measured according to JIS K6301. (The same applies hereinafter)

(Example 2) Epoxy coat 8 of epoxy resin
28 (as described above) A mixture of 10 parts of the epoxy compound represented by the formula (I) used in Example 1, 10 parts of vinylmethyldichlorosilane, dimethyldichlorosilane, and phenyltrichlorosilane in 100 parts was co-hydrolyzed at 90 ° C. , Separated, washed with water until neutral, and remained with hexamethyldisilazane
After trimethylsilylation of OH group, further washing with water and neutralization,
50 parts of an organopolysiloxane represented by the following average composition formula (IV) (CH ₃ ) _1.02 (C ₆ H ₅ ) _0.40 (CH ₂ = CH) _0.08 SiO _1.25 (IV) obtained by isolation 2 parts of the organohydrogenpolysiloxane represented by the formula (III) used in Example 1, 3 parts of methylhydrogenpolysiloxane having a viscosity of 2 centipoise represented by the following formula (V),
1.5 parts of diphenylsilanediol, 0.6 part of aluminum benzoate, and 0.3 part of an isopropanol solution of chloroplatinic acid (platinum content: 0.5%) were added to obtain a silicone-epoxy resin composition (C).

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Next, a molded article integrated in the same manner as in Example 1 except that the silicone-epoxy resin composition (C) was used instead of the silicone-epoxy resin composition (A) of Example 1. I got When the hardness was measured after treating the obtained integrated product in the same manner as in Example 1, the silicone-epoxy resin part was 95 or more according to JIS A and the silicone rubber part was 35 according to JIS A.

Example 3 100 parts of dimethylpolysiloxane having a viscosity of 100,000 centipoise and both ends of a molecular chain blocked with a trivinylsiloxy group were mixed with 30 parts of fumed silica having a specific surface area of 200 m ² / g, 6 silazane,
2 parts of water was added and mixed by heating at 150 ° C. for 3 hours, and 50 ml of the above-mentioned dimethylpolysiloxane blocked with trivinylsiloxy group was added thereto.
Part, 1,6-bis (t-butylperoxy) hexane
1.0 part was added to obtain a silicone rubber composition (D). Silicone-epoxy resin composition (C) used in Example 2
Was injected in the same manner using the same mold as in Example 1, cured at 170 ° C. for 2 minutes, and then the silicone rubber composition (D) was similarly injected onto the silicone-epoxy resin composition (C). The mixture was cured by heating at 170 ° C. for 5 minutes to obtain an integrated product in which the silicone-epoxy resin and the silicone rubber were firmly adhered. After this integrated material was post-cured at 170 ° C. for 3 hours, the hardness of each was measured. The silicone-epoxy resin portion was 95 or more according to JIS A and the silicone rubber portion was J.
It was 40 in ISA.

(Example 4) Epicoat 8 of epoxy resin
28 (as described above) A mixture of 10 parts of the epoxy compound represented by the formula (I) used in Example 1, 10 parts of vinylmethyldichlorosilane, dimethyldichlorosilane, and phenyltrichlorosilane in 100 parts was co-hydrolyzed at 90 ° C. , Separated, washed with water until neutral, and dried to obtain the following average composition formula (VI) (CH ₂ = CH) _0.1 (CH ₃ ) _0.6 (C ₆ H ₅ ) _0.55 (HO) _0.25 SiO _1.25 ..50 parts of the organopolysiloxane represented by (VI), 8 parts of the organohydrogenpolysiloxane represented by the formula (III) used in Example 1, 0.6 part of aluminum benzoate, and an isopropanol solution of chloroplatinic acid (platinum) Content 0.5%)
0.1 part of silicone-epoxy resin composition (E)
I got Next, an integrated molded article was obtained in the same manner as in Example 1, except that the silicone-epoxy resin composition (E) was used instead of the silicone-epoxy resin composition (A) of Example 1. . When the hardness was measured after treating the obtained integrated product in the same manner as in Example 1, the silicone-epoxy resin part was 95 or more according to JIS A and the silicone rubber part was 35 according to JIS A.

Example 5 70 parts of dimethylpolysiloxane having a viscosity of 5,000 centipoise and having both ends of molecular chains blocked with dimethylvinylsiloxy groups, 30 parts of fumed silica having a specific surface area of 300 m ² / g, and hexamethyldisiloxane 6 silazane,
3 parts of water was added and mixed by heating at 150 ° C. for 3 hours, and 50 parts of the above-mentioned dimethylvinylsiloxy-blocked dimethylpolysiloxane, and a dimethylsiloxane-methylhydrogensiloxane copolymer having a viscosity of 10 centipoise and capped at both ends with a trimethylsilyl group were added. (Dimethylsiloxane unit 50 mol%,
Methyl hydrogen siloxane unit 50 mol%) 0.45
Part, chloroplatinic acid in isopropanol solution (platinum content
(0.5%) 0.1 part was added to obtain a silicone rubber composition (G). Next, the cavity 2 of the lower mold 1 shown in FIG.
The above silicone rubber composition (G) is poured into
After heating and curing for 90 seconds, the upper mold 3 is placed on the lower mold 1, the lower mold 1 is closed, and the upper mold 3 is filled through the injection port 4 provided on the upper mold 3, as described in Example 4. The silicone-epoxy resin composition (E) was injected at an injection pressure of 60 kg / cm ² and heated and cured at 150 ° C. for 7 minutes to obtain an integrated product in which the silicone-epoxy resin and silicone rubber were firmly adhered. After this integrated material was post-cured at 150 ° C. for 3 hours, the hardness of each was measured.
The silicone-epoxy resin part had a JIS A of 95 or more (measurement limit or more).

Comparative Example 1 Epicoat 8 of Epoxy Resin
28 (supra) 100 parts of the epoxy compound represented by the formula (I) used in Example 1, 10 parts of diphenylsilanediol
1.5 parts and 0.5 parts of aluminum benzoate were added to obtain an epoxy resin composition (F). Next, the epoxy resin composition (F) is injected into the cavity 2 of the lower mold 1 shown in FIG. 1 in a half amount, and is heated and cured at 150 ° C. for 3 minutes. The lower mold 1 is closed, and the silicone rubber composition (B) used in Example 1 is injected onto the epoxy resin composition (F) from the injection port 4 provided on the upper mold 3 at an injection pressure. Injected at 60 kg / cm ² and cured by heating at 150 ° C for 5 minutes, but it was not possible to obtain an integrated product of both, and the epoxy resin adhered to the mold and was removed from the mold I couldn't do that.

[0042]

The composite of the silicone-epoxy resin and the silicone rubber of the present invention is an integrated product in which both are firmly adhered, and each of them is sufficiently cured to exhibit the original characteristics. It is advantageous for use in various fields such as electronics, OA equipment, automobiles, and precision equipment. Further, this complex can be easily produced by the production method of the present invention.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a longitudinal section of a mold used in Examples and Comparative Examples of the present invention, and is a view for explaining a molding operation.

[Explanation of symbols]

 1 Lower mold 2 Cavity 3 Upper mold 4 Injection

Continued on the front page (72) Inventor Yoshiteru Kobayashi 1-10 Hitomi, Matsuida-machi, Usui-gun, Gunma Prefecture Inside Silicone Electronics Materials Technology Laboratory, Shin-Etsu Chemical Co., Ltd. (56) References JP-A-60-177030 (JP, A (58) Fields surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 C08J 5/12

Claims (4)

(57) [Claims] 1. A composite of a silicone rubber and a silicone-epoxy resin in which a cured product of the following (a) and a cured product of (b) are directly bonded and integrated upon curing. (A) Organic peroxide-curable or addition-curable silicone rubber
And (b) a curable silicone-epoxy resin composition comprising the following 1) to 6). 1) 100 parts by weight of a curable epoxy resin; 2) 5 to 500 parts by weight of an organopolysiloxane containing at least two lower alkenyl groups in one molecule ; 3) bonded to at least one silicon atom in one molecule. a hydrogen atom, generally set Narushiki ^{_{R 4 f H g SiO (4}} -fg) / 2 ( wherein, R ⁴ may be the same or different from each other, aliphatic unsaturated C1-12 does not include the coupling represents a substituted or unsubstituted monovalent hydrocarbon group, f is 1 ≦ f ≦ 2.4, g is 0 <organo Hyde Roger emissions polysiloxane second component 100, represented by representing the g ≦ 1) 1 to 50 parts by weight, 4) 0.1 to 10 parts by weight of an organosilicon compound having at least one silanol group in one molecule , 5) 0.001 to 10 parts by weight of an organoaluminum compound, and 6) a platinum group compound 0.1-500 based on 1,000,000 parts by weight of second component as platinum group metal Parts by weight. 2. A cured product of the following (a) and a cured product of (c):
Is directly bonded and integrated with the silicone rubber upon curing.
Composite of silicone-epoxy resin. (A) Organic peroxide-curable or addition-curable silicone rubber
Curable silicone composed of (c) the following 1) to 5)
-Epoxy resin compositions. 100 parts by weight 1) curable epoxy resin, 2) having hydrogen atoms bonded to at least one silicon atom in a molecule, generally set Narushiki ^{_{R 4 f H g SiO (4}} -fg) / 2 ( wherein among, R ⁴ may be the same or different from each other, represent a monovalent hydrocarbon radical unsubstituted or substituted containing no aliphatic unsaturated bonds TansoHara child number 1 to 12, f is 1 ≦ f ≦ 2.4, g is 0 <1 to 50 parts by weight based on the organohydrogenpolysiloxane III below 100 parts by weight of the component represented by the representative of g ≦ 1), 3) average of at least two lower alkenyl in each molecule having a group and at least one sheet silanol group, the general formula ^{_{R 7 i (HO) j SiO}} (4-ij) / 2 ( wherein, R ⁷ may be the same or different from each other, carbon atoms Represents an unsubstituted or substituted monovalent hydrocarbon group of the formulas 1 to 12 , in which 2 to 80 mol% is a lower alkenyl group, i is 1 ≦ i ≦ 2.5, and j is 0 <J ≦ 2, i + j is 1 <i + j ≦ 3 organopolysiloxane San 5-500 parts by weight, represented by a representative), 4) the organoaluminum compound from 0.001 to 10 parts by weight and 5) a platinum group compound platinum group metal 0.1 to 500 parts by weight per 1 million parts by weight of 3 components. 3. One of the following (a) or (b):
A method for producing a composite of a silicone rubber and a silicone-epoxy resin, wherein the composition is cured at room temperature or under heating, and then cured at room temperature or under heating by bringing the other composition into close contact. (A) Organic peroxide-curable or addition-curable silicone rubber
Curable silicone comprising the following composition: (b) 1) to 6) below
-Epoxy resin compositions. 1) 100 parts by weight of a curable epoxy resin; 2) 5 to 500 parts by weight of an organopolysiloxane containing at least two lower alkenyl groups in one molecule ; 3) bonded to at least one silicon atom in one molecule. a hydrogen atom, generally set Narushiki R ⁴ _f H _g SiO in _{(4-fg) / 2 (wherein,} R ⁴ may be the same or different from each other, aliphatic TansoHara terminal number from 1 to 12 non represents an unsubstituted or substituted monovalent hydrocarbon group not containing an unsaturated bond, f is 1 ≦ f ≦ 2.4, g is 0 <organohydrogenpolysiloxane second component 100, represented by representing the g ≦ 1) 1 to 50 parts by weight, 4) 0.1 to 10 parts by weight of an organosilicon compound having at least one silanol group in one molecule , 5) 0.001 to 10 parts by weight of an organoaluminum compound, and 6) a platinum group compound 0.1 to 500 weight per 1,000,000 parts by weight of second component as platinum group metal Part. 4. A silicone rubber and a silicone-epoxy, wherein one of the following (a) or (c) is cured at room temperature or under heating, and then the other composition is adhered and cured at room temperature or under heating. A method for producing a resin composite. (A) Organic peroxide-curable or addition-curable silicone rubber
(C) a curable silicone-epoxy resin composition comprising 1) to 5 ) below . 100 parts by weight 1) curable epoxy resin, 2) having hydrogen atoms bonded to at least one silicon atom in a molecule, generally set Narushiki ^{_{R 4 f H g SiO (4}} -fg) / 2 ( wherein among, R ⁴ may be the same or different from each other, represent a monovalent hydrocarbon radical unsubstituted or substituted containing no aliphatic unsaturated bonds TansoHara child number 1 to 12, f is 1 ≦ f ≦ 2.4, g is 0 <1 to 50 parts by weight based on the organohydrogenpolysiloxane III below 100 parts by weight of the component represented by the representative of g ≦ 1), 3) average of at least two lower alkenyl in each molecule having a group and at least one sheet silanol group, the general formula ^{_{R 7 i (HO) j SiO}} (4-ij) / 2 ( wherein, R ⁷ may be the same or different from each other, carbon atoms represents a monovalent hydrocarbon radical unsubstituted or substituted C 1 -C 12, a of which 2-80 mol% is lower alkenyl group, i is 1 ≦ i ≦ 2.5, j is 0 j ≦ 2, i + j is 1 <i + j ≦ 3 organopolysiloxane San 5-500 parts by weight, represented by a representative), 4) an organoaluminum compound from 0.001 to 10 parts by weight and 5) a platinum group compound platinum group 3 metal 0.1 to 500 parts by weight per 1 million parts by weight of component.