WO2018055851A1

WO2018055851A1 - Organopolysiloxane composition for resin-adhesive oil seal and oil seal for motor vehicle

Info

Publication number: WO2018055851A1
Application number: PCT/JP2017/022053
Authority: WO
Inventors: 晃打它; 坂本　隆文
Original assignee: 信越化学工業株式会社
Priority date: 2016-09-21
Filing date: 2017-06-15
Publication date: 2018-03-29
Also published as: JPWO2018055851A1; JP6699743B2

Abstract

This organopolysiloxane composition for a resin-adhesive oil seal comprising: a silane coupling agent having at least one functional group other than an isocyanate group, said functional group containing a nitrogen atom, a sulfur atom, or an oxygen atom, and/or a partially hydrolyzed condensate of the silane coupling agent; and an isocyanate silane compound, and/or a partially hydrolyzed condensate thereof, in which an amount of a curing agent is adjusted and a high-viscosity base oil is used, can be suitably used as an oil seal for a motor vehicle, and in particular, has exceptional initial pressure resistance performance in rapid curing, improves adhesion and adhesive strength to a resin oil pan, and imparts a cured product with favorable elongation and engine oil resistance.

Description

Organopolysiloxane composition for resin adhesive oil seal and oil seal for automobile

The present invention relates to an organopolysiloxane composition for resin-adhesive oil seals that can be suitably used as an oil seal for automobiles, and in particular, is excellent in initial pressure resistance due to rapid curing and improved in adhesion and adhesive strength to resin oil pans. And an organopolysiloxane composition that gives a cured product having good elongation and resistance to engine oil, and an oil seal for automobiles obtained by curing the composition.

Conventionally, oil-resistant gaskets and packing materials made of cork, organic rubber, asbestos, etc. have been used for the seals around the engine for automobiles, but these require complicated inventory management and work processes. There are disadvantages and further disadvantages are that their sealing performance is unreliable. Therefore, the FIPG method (Formed In Place Gasket) using a room temperature curable organopolysiloxane composition as a liquid gasket is used for this type of application.

In recent years, attempts have been made to partially convert metals used in automobile engines from the viewpoint of improving fuel economy and weight reduction of automobiles. As the resin employed as such a member, a resin having a low rate of change with respect to mechanical properties and a durability test against engine oil, that is, a resin that is very stable mechanically and chemically is selected. Resins with high chemical stability have no or very few active groups, so it is difficult to obtain good adhesion and to maintain stable adhesion. . As a technique for improving the adhesion to a resin, a method of adding an oligomer of an aminosilane coupling agent to a room temperature curable organopolysiloxane composition (Japanese Patent No. 3714862: Patent Document 1) is known. When an oligomer of an aminosilane coupling agent was blended in a composition for oil seal use, it could not be used due to poor engine oil resistance. In addition, a method for selecting a filler of a dealcohol-free room temperature curable organopolysiloxane composition (Japanese Patent Laid-Open No. 2004-292724: Patent Document 2) and a method for selecting a structure of a titanium catalyst used as a curing catalyst ( Japanese Patent Nos. 4438937, 4530136, 4658654, and 4530177: Patent Documents 3 to 6) are known, but these compositions are dealcohol-type compositions. Therefore, there are problems that it takes time to obtain a cured product and that the engine oil resistance is inferior to FIPG that has been used conventionally. In addition, as a method for improving adhesion to various adherends, a report that magnesium adhesiveness is improved when a reaction product of isocyanate silane and acetic acid is used as an adhesion promoter (Patent No. 4662056: Patent Document 7), and isocyanate silane is used. As a result, a report has been reported that the oil surface adhesion is improved (Japanese Patent Laid-Open No. 2010-037507: Patent Document 8) and a method using isocyanurate silane (Japanese Patent Laid-Open No. 2015-021019: Patent Document 9). There are no reports of improving the adhesion to chemically highly stable resins.

Japanese Patent No. 3714861 JP 2004-292724 A Japanese Patent No. 4438937 Japanese Patent No. 4530136 Japanese Patent No. 4658654 Japanese Patent No. 4530177 Japanese Patent No. 4662056 JP 2010-037507 A1 Japanese Patent Laying-Open No. 2015-021019 Japanese Patent Laid-Open No. 5-105689

The present invention has been made in view of the above circumstances, and is suitably used as an oil seal for automobiles, and in particular, has excellent initial pressure resistance due to rapid curing, and improves adhesion and adhesive strength to a resin oil pan, and It is an object of the present invention to provide an organopolysiloxane composition for resin-adhesive oil seals that gives a cured product having good elongation and engine oil resistance, and an automotive oil seal obtained by curing the composition.

As a result of intensive studies to achieve the above object, the present inventors have found that a silane coupling agent having at least one functional group other than an isocyanate group containing a nitrogen atom, a sulfur atom, or an oxygen atom and / or its silane coupling agent. By using a partially hydrolyzed condensate and a hydrolyzable isocyanate silane compound and / or a partially hydrolyzed condensate thereof, the resulting cured product has good adhesion and oil resistance, and the amount of curing agent is reduced. By adjusting, it was found that an organopolysiloxane composition for resin-adhesive oil seals that has a high curability and that has achieved high elongation can be obtained by using a base oil with high viscosity. The present invention has been made.

That is, the present invention provides the following organopolysiloxane composition for resin-adhesive oil seals and an automotive oil seal obtained by curing the composition.
[1]
(A) 100 parts by mass of an organopolysiloxane having a viscosity at 23 ° C. represented by the following general formula (1) of 2,000 mPa · s or more,
HO— (SiR ¹ ₂ O) _a —H (1)
(Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ¹ may be the same or different from each other. A is an integer of 100 or more. is there.)
(B) 1 to 500 parts by mass of an inorganic filler,
(C) 1-30 parts by mass of a hydrolyzable (organo) silane compound having three or more ketoxime groups represented by the following general formula (2) in one molecule;
R ² _b Si (ON—CR ³ ₂ ) _4-b (2)
(Wherein R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms. B Is 0 or 1.)
(D) 0.01 to 5 parts by mass of a silane coupling agent represented by the following general formula (3) and / or a partial hydrolysis condensate thereof,
R ⁴ R ⁶ _c Si (OR ⁵ ) _3-c (3)
(Wherein R ⁴ is a monovalent hydrocarbon having 1 to 20 carbon atoms having at least one functional group other than an isocyanate group containing at least one atom selected from a nitrogen atom, a sulfur atom and an oxygen atom) R ⁵ and R ⁶ are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and c is 0, 1 or 2.)
(E) Hydrolyzable isocyanate silane compound represented by the following general formula (5) and / or its partial hydrolysis condensate: 0.01 to 3 parts by mass,

(Wherein R ¹² and R ¹³ are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R ¹⁴ is a divalent hydrocarbon group having 1 to 10 carbon atoms, and f is (It is an integer from 1 to 3.)
(F) Curing catalyst An organopolysiloxane composition for resin-adhesive oil seals, comprising 0.01 to 0.5 parts by mass.
[2]
(B) The resin adhesive according to [1], wherein the inorganic filler as the component is at least one selected from calcium carbonate, fumed silica, precipitated silica, carbon black, and aluminum oxide, which has been treated with a surface treating agent. An organopolysiloxane composition for oil seals.
[3]
The silane coupling agent of component (D) has the following general formula (4)

(Wherein R ⁸ and R ⁹ are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R ¹⁰ is a divalent hydrocarbon group having 1 to 10 carbon atoms, and R ¹¹ Is a divalent hydrocarbon group having 7 to 10 carbon atoms including an aromatic ring, and e is an integer of 1 to 3, provided that at least one of the NH group and the NH ₂ group is directly connected to the aromatic ring of R ^11. Absent.)
The organopolysiloxane composition for resin-adhesive oil seals according to [1] or [2], which comprises a hydrolyzable organosilane compound and / or a partially hydrolyzed condensate thereof.
[4]
An automotive oil seal comprising a cured product of the organopolysiloxane composition for resin adhesive oil seals according to any one of [1] to [3].

According to the present invention, in particular, room temperature curability that provides fast cured and excellent initial pressure resistance, improved adhesion to resin oil pans and adhesion strength, and provides a cured product having good elongation and engine oil resistance. An organopolysiloxane composition for resin adhesive oil seals can be obtained.

Hereinafter, the present invention will be described in more detail.
The component (A) of the organopolysiloxane composition for resin adhesive oil seal used in the present invention is represented by the following general formula (1), the main chain is composed of repeating diorganosiloxane units, and both ends of the molecular chain are A linear diorganopolysiloxane having a viscosity at 23 ° C. of 2,000 mPa · s or more which is blocked with a hydroxyl group (silanol group) bonded to a silicon atom, and acts as a main agent (base polymer) of the composition of the present invention. To do.
HO— (SiR ¹ ₂ O) _a —H (1)
(Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ¹ may be the same or different from each other. A is an integer of 100 or more. is there.)

In the above formula (1), R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms. For example, methyl group, ethyl group, propyl group, butyl group, hexyl Group, alkyl group such as octyl group; cycloalkyl group such as cyclohexyl group; alkenyl group such as vinyl group, allyl group, propenyl group, butenyl group, hexenyl group; aryl group such as phenyl group, tolyl group; benzyl group, phenyl An aralkyl group such as an ethyl group, or a group in which the hydrogen atom of these groups is partially substituted with a halogen atom such as chlorine, fluorine or bromine, such as a trifluoropropyl group, is preferred, and a methyl group and a phenyl group are preferred. A methyl group is particularly preferred. R ¹ may be the same group or a different group.

In the formula (1), a is an integer of 100 or more (usually 100 to 2,000), preferably 150 to 1,000, more preferably about 200 to 800. The organopolysiloxane at 23 ° C. The viscosity is 2,000 mPa · s or more, usually in the range of 2,000 to 500,000 mPa · s, preferably in the range of 3,000 to 500,000 mPa · s, particularly in the range of 5,000 to 100,000 mPa · s. It is preferable to be in the range. In the present invention, the viscosity is a value measured by a rotational viscometer (for example, BL type, BH type, BS type, cone plate type, etc.). In the present invention, the degree of polymerization (or molecular weight) is, for example, a number average degree of polymerization (or number average molecular weight) in terms of polystyrene in gel permeation chromatography (GPC) analysis using toluene, tetrahydrofuran (THF) or the like as a developing solvent. And so on.
(A) The organopolysiloxane of a component may be 1 type and may use 2 or more types together.

Next, the inorganic filler as the component (B) is a reinforcing or non-reinforcing filler for imparting rubber physical properties to the present composition. Examples of the filler include silica-based fillers such as surface-treated or untreated dry silica such as calcined silica and fumed silica, wet silica such as precipitated silica and sol-gel silica, carbon black, talc and bentonite. , Surface treated or untreated calcium carbonate, zinc carbonate, magnesium carbonate, surface treated or untreated calcium oxide, zinc oxide, magnesium oxide, aluminum oxide, aluminum hydroxide, etc., among which calcium carbonate, fumed silica Precipitating silica, carbon black, and aluminum oxide are preferable, and calcium carbonate, fumed silica, precipitating silica, carbon black, and aluminum oxide are more preferable. In this case, these inorganic fillers preferably have a low water content.
In addition, although there is no restriction | limiting in particular about the kind of this surface treating agent, an amount, a processing method, etc., Typically, organosilicon compounds, such as chlorosilane, alkoxysilane, and organosilazane, fatty acid, paraffin, a silane coupling agent, Treatment agents such as titanium coupling agents can be applied.

(B) The inorganic filler of a component may be 1 type and may use 2 or more types together.
The amount of component (B) is in the range of 1 to 500 parts by weight, preferably in the range of 20 to 300 parts by weight, per 100 parts by weight of the organopolysiloxane of component (A). If it is less than 1 part by mass, sufficient rubber strength cannot be obtained, so that there is a problem that it is not suitable for the intended use. If it exceeds 500 parts by mass, the dischargeability from the cartridge is deteriorated and the storage stability is reduced. The mechanical properties of the rubber properties are also reduced.

Next, a hydrolyzable (organo) silane compound having 3 or more (that is, 3 or 4) ketoxime groups represented by the following general formula (2) as component (C) is obtained in one molecule. In the composition, it is a component generally called a curing agent for imparting good storage stability to the composition under hermetic conditions and reacting with moisture in the air after opening to make it rubber.
R ² _b Si (ON—CR ³ ₂ ) _4-b (2)
(Wherein R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms. B Is 0 or 1.)

In the above formula (2), R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and examples thereof are the same as R ^{1 in} the above formula (1). 6 unsubstituted or substituted monovalent hydrocarbon groups are preferable, and a methyl group, a vinyl group, and a phenyl group are particularly preferable.
R ³ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms. Examples of R ³ are the same as those of R ¹ in the above formula (1), as in R ^2. 6 unsubstituted or substituted monovalent hydrocarbon groups are preferred, and those selected from methyl, ethyl, propyl, butyl, and isobutyl groups are particularly preferred.
R ² and R ³ may be the same group or different groups.

Specific examples of the hydrolyzable (organo) silane compound (C) include methyltris (dimethylketoxime) silane, methyltris (methylethylketoxime) silane, methyltris (methylisobutylketoxime) silane, methyltris (methylpropylketoxime) Silane, methyltris (methylbutylketoxime) silane, vinyltris (methylethylketoxime) silane, vinyltris (dimethylketoxime) silane, vinyltris (methylisobutylketoxime) silane, vinyltris (methylpropylketoxime) silane, vinyltris (methylbutylketoxime) ) Ketooxime silanes such as silane, tetra (methyl ethyl ketoxime) silane, tetra (methyl isobutyl ketoxime) silane These can be used in combination alone, or two or more kinds.
In addition, the hydrolyzable (organo) silane compound of component (C) is a component that does not contain a ketoxime group in the molecule in that the ketoxime group is essential in the molecule. The silane coupling agent and / or its partially hydrolyzed condensate, and the hydrolyzable isocyanate silane compound and / or its partially hydrolyzed condensate as component (E) are clearly differentiated.

The hydrolyzable (organo) silane compound (C) is used in an amount of 1 to 30 parts by weight, preferably 3 to 15 parts by weight, based on 100 parts by weight of the organopolysiloxane (A). If the amount is less than 1 part by mass, sufficient crosslinking cannot be obtained, and the composition having the desired rubber elasticity cannot be obtained. If the amount exceeds 30 parts by mass, the mechanical properties and curability of the obtained rubber properties are reduced. End up.

Next, the component (D) is a silane coupling agent represented by the following general formula (3) (that is, a hydrolyzable carbon functional organosilane compound having a functional group-containing monovalent hydrocarbon group) and / or its It is a partially hydrolyzed condensate and an essential component for allowing the composition to exhibit good adhesiveness.
R ⁴ R ⁶ _c Si (OR ⁵ ) _3-c (3)
(Wherein R ⁴ is a monovalent hydrocarbon having 1 to 20 carbon atoms having at least one functional group other than an isocyanate group containing at least one atom selected from a nitrogen atom, a sulfur atom and an oxygen atom) A group (so-called carbon functional group), wherein R ⁵ and R ⁶ are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, c is 0, 1 or 2; Preferably it is 0 or 1.)

In the above formula (3), R ⁴ is a functional group other than an isocyanate group containing an atom selected from a nitrogen atom, a sulfur atom and an oxygen atom (for example, an unsubstituted or substituted amino group, an unsubstituted or substituted imino group, an amide group). , A ureido group, a mercapto group, an epoxy group, a (meth) acryloxy group, etc.) and a monovalent hydrocarbon group having 1 to 20 carbon atoms, specifically β- (2,3-epoxycyclohexyl). ) Ethyl group, β- (3,4-epoxycyclohexyl) ethyl group, γ-glycidoxypropyl group, γ- (meth) acryloxypropyl group, γ-acryloxypropyl group, N-β (aminoethyl)- γ-aminopropyl group, γ-aminopropyl group, N-phenyl-γ-aminopropyl group, γ-ureidopropyl group, γ-mercaptopropyl group, γ-isocyanate propylene Nitrogen atom of the group, having 3 to carbon atoms other than isocyanate group containing at least one atom selected from a sulfur atom and an oxygen atom 20, in particular include monovalent hydrocarbon group having 8 to 14 carbon atoms.

R ⁵ and R ⁶ are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, and is the same as R ^{1 in} the above formula (1). Examples thereof include alkyl groups such as methyl group, ethyl group, propyl group and isopropyl group.

Specific examples of the component (D) silane coupling agent include carbon atoms having at least one functional group other than an isocyanate group containing any one or more atoms selected from a nitrogen atom, a sulfur atom, and an oxygen atom. As long as it is a hydrolyzable silane compound containing 1 to 20 monovalent hydrocarbon groups and containing 1 to 3 organooxy groups such as alkoxy groups, any component can be used. Among them, when a hydrolyzable organosilane compound represented by the following general formula (4) and / or a partially hydrolyzed condensate thereof is used, adhesion and chemical resistance are further improved.

(Wherein R ⁸ and R ⁹ are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R ¹⁰ is a divalent hydrocarbon group having 1 to 10 carbon atoms, and R ¹¹ Is a divalent hydrocarbon group having 7 to 10 carbon atoms containing an aromatic ring, and e is an integer of 1 to 3, preferably 2 or 3, more preferably 3, provided that at least of the NH group and the NH ₂ group One is not directly connected to the aromatic ring of R ^11. )

The silane compound represented by the above formula (4) has an NH group (imino group) and an NH ₂ group (amino group), includes an aromatic ring between the NH group and the NH ₂ group, and further includes an NH group and This is an alkoxysilane compound in which at least one of the NH ₂ groups is not directly bonded to the carbon atom constituting the aromatic ring, and is described in detail in JP-A-5-105689.

In the above formula (4), the unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms of R ⁸ and R ⁹ is a methyl group, an ethyl group, a propyl group, a butyl group, or a hexyl group. Alkyl groups such as cyclohexyl groups; cycloalkyl groups such as cyclohexyl groups; alkenyl groups such as vinyl groups, allyl groups, propenyl groups, butenyl groups, hexenyl groups; aryl groups such as phenyl groups, tolyl groups; benzyl groups, phenylethyl groups, etc. Aralkyl groups and the like can be mentioned, and R ⁸ is preferably a methyl group or an ethyl group, and R ⁹ is preferably a methyl group.

Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms of R ¹⁰ include methylene group, ethylene group, propylene group, tetramethylene group, hexamethylene group, octamethylene group, decamethylene group, and 2-methylpropylene group. Examples thereof include an arylene group such as an alkylene group and a phenylene group, and a group in which the alkylene group and the arylene group are bonded, and a methylene group, an ethylene group, and a propylene group are preferable, and a propylene group is particularly preferable.

Further, the divalent hydrocarbon group having 7 to 10 carbon atoms including the aromatic ring of R ¹¹ is preferably a group in which a phenylene group and an alkylene group are bonded, and examples thereof include those represented by the following formula.
—C ₆ H ₄ —CH ₂ —
—C ₆ H ₄ —CH ₂ —CH ₂ —
—C ₆ H ₄ —CH ₂ —CH ₂ —CH ₂ —
—CH ₂ —C ₆ H ₄ —
—CH ₂ —C ₆ H ₄ —CH ₂ —
—CH ₂ —C ₆ H ₄ —CH ₂ —CH ₂ —
—CH ₂ —C ₆ H ₄ —CH ₂ —CH ₂ —CH ₂ —
—CH ₂ —CH ₂ —C ₆ H ₄ —
—CH ₂ —CH ₂ —C ₆ H ₄ —CH ₂ —
—CH ₂ —CH ₂ —C ₆ H ₄ —CH ₂ —CH ₂ —
—CH ₂ —CH ₂ —CH ₂ —C ₆ H ₄ —
—CH ₂ —CH ₂ —CH ₂ —C ₆ H ₄ —CH ₂ —
Of these, —CH ₂ —C ₆ H ₄ —CH ₂ — is particularly preferred.

In this case, the alkylene group bonded to the right side of the phenylene group (NH ₂ side in the formula (4)) (when there is no alkylene group, it is —NH ₂ group) may be in the ortho, meta, or para position. Good.

The following are illustrated as a silane compound shown by the said General formula (4).

As the component (D), the silane coupling agent and / or the partial hydrolysis condensate thereof may be one kind or a combination of two or more kinds.
In the present invention, the partially hydrolyzed condensate is a residual hydrolyzate produced in the molecule, which is produced by partially hydrolyzing one or more of the raw material hydrolyzable organosilane compounds (silane coupling agents). It means an organopolysiloxane (oligomer) containing at least 2, preferably 3 or more decomposable groups (for example, organooxy groups such as unsubstituted or substituted alkoxy groups).
In addition, the silane coupling agent of component (D) and / or its partial hydrolysis-condensation product, which does not contain an isocyanate group in the molecule, will essentially contain an isocyanate group in the molecule, which will be described later. The (E) component hydrolyzable isocyanate silane compound and / or its partial hydrolysis condensate is clearly differentiated.

The blending amount of the component (D) is 0.01 to 5 parts by mass, preferably 0.1 to 3 parts by mass, with respect to 100 parts by mass of the organopolysiloxane of the component (A). If it is less than 0.01 part by mass, the cured product does not exhibit sufficient adhesion performance, and if it exceeds 5 parts by mass, the rubber strength after curing is lowered or the curability is lowered.

Next, the hydrolyzable isocyanate silane compound and / or its partially hydrolyzed condensate represented by the following general formula (5), which is the component (E), reacts with the component (D) during mixing and has good adhesiveness. And imparts oil resistance to the composition.

(Wherein R ¹² and R ¹³ are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R ¹⁴ is a divalent hydrocarbon group having 1 to 10 carbon atoms, and f is An integer of 1 to 3, preferably 2 or 3, more preferably 3.)

In the above formula (5), the unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms of R ¹² and R ¹³ is a methyl group, an ethyl group, a propyl group, a butyl group, or a hexyl group. Alkyl groups such as cyclohexyl groups; cycloalkyl groups such as cyclohexyl groups; alkenyl groups such as vinyl groups, allyl groups, propenyl groups, butenyl groups, hexenyl groups; aryl groups such as phenyl groups, tolyl groups; benzyl groups, phenylethyl groups, etc. Aralkyl groups and the like can be mentioned. R ¹² is preferably a methyl group or an ethyl group, and R ¹³ is preferably a methyl group.

Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms of R ¹⁴ include a methylene group, an ethylene group, a propylene group, a tetramethylene group, a hexamethylene group, an octamethylene group, a decamethylene group, and a 2-methylpropylene group. Examples thereof include an arylene group such as an alkylene group and a phenylene group, and a group in which the alkylene group and the arylene group are bonded, and a methylene group, an ethylene group, and a propylene group are preferable, and a propylene group is particularly preferable.

Specific examples of the component (E) include 3-isocyanatepropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatepropyltripropoxysilane, 3-isocyanatepropylmethyldimethoxysilane, 3-isocyanatepropyldimethylmethoxysilane, 3-isocyanatopropylethyldimethoxysilane, 4-isocyanatobutyltrimethoxysilane, 5-isocyanatepentyltrimethoxysilane, 6-isocyanatohexyltrimethoxysilane, 7-isocyanatoheptyltrimethoxysilane, 8-isocyanateoctyltrimethoxysilane and parts thereof Although a hydrolysis-condensation product can be illustrated, it is not this limitation. Of these, 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane can be preferably used.

The blending amount of the component (E) is 0.01 to 3 parts by mass, preferably 0.1 to 1.5 parts by mass with respect to 100 parts by mass of the organopolysiloxane of the component (A). If the blending amount is less than the above range, there is a possibility that the desired cured product (silicone rubber) adhesion and rubber properties (mechanical properties such as hardness, elongation and strength) may not be obtained. There is a risk of an increase or a decrease in rubber properties.

Next, the curing catalyst of the component (F) is generally called a curing catalyst, which is used for promoting the hydrolysis reaction between the present composition and moisture in the air. It is preferable to use components similar to those used in silicone resin compositions that cure in the presence of moisture, well known in the art.

Examples of the component (F) include a tin-based catalyst, a bismuth-based catalyst, and a titanium-based catalyst, and it is more preferable to use a tin-based catalyst and a bismuth-based catalyst. Specific examples of tin-based catalysts include tin naphthenate, tin caprylate, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltin diacetate, diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy) ) Tin, dibutyltin benzyl malate, dioctyltin diversate, etc. Specific examples of bismuth catalysts include bismuth tris (2-ethylhexanoate) or bismuth tris (neodecanoate) Can do. Specific examples of titanium-based catalysts include titanic acid esters such as tetraisopropoxy titanium, tetra-n-butoxy titanium, tetrabis (2-ethylhexoxy) titanium, dipropoxy bis (acetylacetona) titanium, titanium isopropoxyoctylene glycol, and the like. And titanium chelate compounds.

(F) The curing catalyst of a component may be 1 type and may use 2 or more types together.
The amount of component (F) is in the range of 0.01 to 0.5 parts by weight, preferably in the range of 0.03 to 0.3 parts by weight, based on 100 parts by weight of the organopolysiloxane of component (A). It is. When the amount is less than 0.01 parts by mass, good curability cannot be obtained, which causes a problem that, for example, the time is extended before the engine oil is injected at the time of manufacturing an automobile or the like. On the other hand, when the amount exceeds 0.5 parts by mass, the storage stability of the composition deteriorates and the composition may gel in the container over time.

Moreover, in the composition of the present invention, additives that are generally known in addition to the above components may be used within a range that does not impair the object of the present invention. Additives include polyethers as thixotropic agents, silicone oils as plasticizers, isoparaffins, etc., if necessary, colorants such as pigments, dyes, fluorescent brighteners, fungicides, antibacterial agents , Bioactive additives such as marine organism repellent, phenyl silicone oil as bleed oil, fluorosilicone oil, surface modifiers such as organic liquid incompatible with silicone, toluene, xylene, solvent volatile oil, cyclohexane, methyl Solvents such as cyclohexane and low boiling point isoparaffin can also be added.

The organopolysiloxane composition for resin adhesive oil seals of the present invention is a room temperature curable composition. As the curing conditions, for example, the composition (room temperature curable organopolysiloxane composition) is formed into a 2 mm formwork. The cured product (silicone rubber sheet) with a thickness of 2 mm can be obtained by rinsing (stationary) for 7 days at 23 ° C. and 50% RH.

In addition, the organopolysiloxane composition for resin adhesive oil seal of the present invention is suitably used as an oil seal for automobiles, and is particularly fast curing and excellent in initial pressure resistance, as well as adhesiveness and adhesive strength to resin oil pans. And a cured product having good elongation and engine oil resistance. In particular, it can be suitably used as a sealing material for resin oil pans for automobile engines.

Hereinafter, the present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited to the following examples. In all of the examples and comparative examples, a planetary mixer (manufactured by Inoue Seisakusho Co., Ltd.) was used as an appropriate mixer. Further, in the following examples, physical properties such as viscosity (measured value by a rotational viscometer) not particularly described indicate values at 23 ° C.

[Example 1]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1 part by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, (D) 3 -1 part by mass of aminopropyltrimethoxysilane (trade name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) and (E) 3-isocyanatopropyltriethoxysilane (trade name: KBE-9007, Shin-Etsu Chemical Co., Ltd.) )) 0.5 part by mass and (F) dioctyltin diversate 0.1 part by mass were added and mixed thoroughly under reduced pressure to obtain Composition 1.

[Example 2]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1.5 parts by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, ) Add 0.5 parts by mass of 3-isocyanatopropyltriethoxysilane (trade name; KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.1 part by mass of (F) dioctyltin diversate, and complete under reduced pressure. The composition 2 was obtained.

[Example 3]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1.5 parts by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, ) Add 0.5 parts by mass of 3-isocyanatopropyltrimethoxysilane (trade name: KBM-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.1 part by mass of (F) dioctyltin diversate, and complete under reduced pressure. The composition 3 was obtained.

[Example 4]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1.5 parts by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, ) Add 0.5 parts by mass of 3-isocyanatopropyltriethoxysilane (trade name: KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) and (F) 0.2 parts by mass of dioctyltin diversate, and complete under reduced pressure. To obtain a composition 4.

[Comparative Example 1]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1.5 parts by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, ) Dioctyltin diversate 0.1 parts by weight was added and thoroughly mixed under reduced pressure to obtain Composition 5.

[Comparative Example 2]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, 1 part by mass of (D) 3-aminopropyltrimethoxysilane (trade name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.1 part by mass of (F) dioctyltin diversate are added, and Were mixed thoroughly to obtain a composition 6.

[Comparative Example 3]
(A) Heavy calcium carbonate having a viscosity of 50,000 mPa · s at 23 ° C. and 100 mass parts of polydimethylsiloxane whose ends are blocked with silanol groups, and (B) a surface treated with fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1 part by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, (D) 3 -1 part by mass of aminopropyltrimethoxysilane (trade name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) and (E) 3-isocyanatopropyltriethoxysilane (trade name: KBE-9007, Shin-Etsu Chemical Co., Ltd.) ) Made) 0.5 parts by mass and (F) dioctyltin diversate 0.001 part by mass were added and mixed thoroughly under reduced pressure to obtain composition 7.

[Comparative Example 4]
(A) Heavy calcium carbonate having a viscosity of 1,000 mPa · s at 23 ° C. and having a terminal end blocked with a silanol group, and (B) a surface treated with a fatty acid (trade name; MC 40 parts by mass of Coat S-20, manufactured by Maruo Calcium Co., Ltd. and (B) 80 parts by mass of colloidal calcium carbonate whose surface is treated with fatty acid (trade name; Carlex 300, manufactured by Maruo Calcium Co., Ltd.) (B) After adding 2 parts by mass of fumed silica whose surface was treated with dimethyldichlorosilane and mixing, (C) 7 parts by mass of vinyltris (methylethylketoxime) silane was added and mixed under reduced pressure. Next, (D) 1 part by mass of a compound (trade name; CF-73, manufactured by Shin-Etsu Chemical Co., Ltd.) obtained by dehydrochlorination reaction of xylylenediamine and 3-chloropropyltrimethoxysilane, (D) 3 -1 part by mass of aminopropyltrimethoxysilane (trade name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) and (E) 3-isocyanatopropyltriethoxysilane (trade name: KBE-9007, Shin-Etsu Chemical Co., Ltd.) ) Made) 0.5 parts by mass and (F) dioctyltin diversate 0.1 part by mass were added and mixed thoroughly under reduced pressure to obtain composition 8.

[Test method]
The composition (organopolysiloxane composition for resin adhesive oil seal) prepared in the above examples and comparative examples is poured into a 2 mm mold and cured for 7 days at 23 ° C. and 50% RH to give a 2 mm thick rubber sheet. Got. The tack free time (touch drying time) was measured according to the method specified in JIS A 5758, and the rubber physical properties (hardness, elongation at break, tensile strength) were measured from a 2 mm thick sheet according to JIS K 6249.

The curing rate test method was to measure the thickness of a glass petri dish having an inner diameter of 10 mm filled with the composition and cured from the portion exposed to air after 1 day at 23 ° C. and 50% RH.

The initial sealability test method was a pressure test using a pressure vessel similar to a flange pressure vessel for pressure test specified in JIS K 6820 as a test apparatus. The pressure vessel comprises an upper vessel having an upper flange having an inner diameter of 58 mm, an outer diameter of 80 mm, and a height of 10 mm, and a lower vessel having a lower flange of the same size as the upper flange, and the inner side of the seal surface of the lower flange An annular cutout having a width of 3 mm and a depth of 3 mm is provided along the circumference of the edge. The sealing surface of the lower flange was washed with toluene. Thereafter, the composition was applied in an application amount sufficient to fill the seal surface, and applied in a bead shape to the central portion of the lower seal surface. Immediately after application, the upper container was placed on the lower container so that the sealing surfaces of the upper flange and the lower flange were in contact with each other, and a 20.50 mm iron spacer was installed and four fastening bolts were assembled. The spacer causes a gap of 0.5 mm between the seal surfaces, which is a so-called accelerated test that makes the pressure test more severe. After curing at 23 ° C. and 50% RH for 30 minutes, a gas was inserted from the upper pressure port, and the gas pressure that could be withstood by the sealant was taken as the seal strength.

Further, from this composition, aluminum 66 (PA66) (trade name: Seidel 80G33HS1L, manufactured by DuPont), nylon 6 (PA6), which is considered to be promising as aluminum resin having a width of 25 mm and a length of 100 mm, and resin for automobile engines. (Trade name; UBE nylon, manufactured by Ube Industries, Ltd.), polybutylene terephthalate (PBT) (trade name; DURANEX 3300, manufactured by Polyplastics Co., Ltd.), polyphenylene sulfide (PPS) (trade name; Thirsty GS) -40, manufactured by Tosoh Corp.), a shear adhesion test specimen having an adhesion area of 2.5 mm ² and an adhesion thickness of 1 mm was prepared and cured at 23 ° C. and 50% RH for 7 days. Using this specimen, the shear adhesive strength and cohesive failure rate for aluminum and each resin were measured according to the method specified in JIS K 6249, and the cohesive failure rates were compared.

In addition, in order to confirm the chemical resistance (engine oil resistance) ability, the obtained cured silicone rubber sheet and shear adhesion test specimen were immersed in engine oil [trade name: Toyota Castle Oil SN 0W-20] Deteriorate at 120 ° C. for 10 days, and then conduct the same tests as the initial stage of production (measurement of rubber physical properties (hardness, elongation at break, tensile strength) and shear adhesive strength and cohesive failure rate for aluminum and each resin). Then, a chemical resistance confirmation test was conducted.

These results are shown in Table 1 below.

Examples 1 to 4 showed good initial sealability, elongation, physical properties, resin adhesion, and oil resistance. On the other hand, in Comparative Examples 1 and 2, the initial resin adhesion was poor, and in Comparative Example 3, the initial sealing property was deteriorated. In Comparative Example 4, the adhesion and oil resistance were good, but the elongation was poor.

From the above results, it can be seen that the organopolysiloxane composition for resin adhesive oil seal according to the present invention is effective.

Claims

(A) 100 parts by mass of an organopolysiloxane having a viscosity at 23 ° C. represented by the following general formula (1) of 2,000 mPa · s or more,
HO— (SiR 1 2 O) a —H (1)
(Wherein R 1 is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R 1 may be the same or different from each other. A is an integer of 100 or more. is there.)
(B) 1 to 500 parts by mass of an inorganic filler,
(C) 1-30 parts by mass of a hydrolyzable (organo) silane compound having three or more ketoxime groups represented by the following general formula (2) in one molecule;
R 2 b Si (ON—CR 3 2 ) 4-b (2)
(Wherein R 2 is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R 3 is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms. B Is 0 or 1.)
(D) 0.01 to 5 parts by mass of a silane coupling agent represented by the following general formula (3) and / or a partial hydrolysis condensate thereof,
R 4 R 6 c Si (OR 5 ) 3-c (3)
(Wherein R 4 is a monovalent hydrocarbon having 1 to 20 carbon atoms having at least one functional group other than an isocyanate group containing at least one atom selected from a nitrogen atom, a sulfur atom and an oxygen atom) R 5 and R 6 are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and c is 0, 1 or 2.)
(E) Hydrolyzable isocyanate silane compound represented by the following general formula (5) and / or its partial hydrolysis condensate: 0.01 to 3 parts by mass,

(Wherein R 12 and R 13 are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R 14 is a divalent hydrocarbon group having 1 to 10 carbon atoms, and f is (It is an integer from 1 to 3.)
(F) Curing catalyst An organopolysiloxane composition for resin-adhesive oil seals, comprising 0.01 to 0.5 parts by mass.
The resin adhesive according to claim 1, wherein the inorganic filler of component (B) is at least one selected from calcium carbonate, fumed silica, precipitated silica, carbon black, and aluminum oxide treated with a surface treating agent. An organopolysiloxane composition for oil seals.
The silane coupling agent of component (D) is represented by the following general formula (4)

(Wherein R 8 and R 9 are each independently an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, R 10 is a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 11 Is a divalent hydrocarbon group having 7 to 10 carbon atoms including an aromatic ring, and e is an integer of 1 to 3, provided that at least one of the NH group and the NH 2 group is directly connected to the aromatic ring of R 11. Absent.)
The organopolysiloxane composition for resin-adhesive oil seals according to claim 1 or 2, which comprises a hydrolyzable organosilane compound and / or a partial hydrolysis condensate thereof.
An automobile oil seal comprising a cured product of the organopolysiloxane composition for resin adhesive oil seals according to any one of claims 1 to 3.