JPH11222524A - Hydrosilylation catalyst and silicone composition using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrosilylation catalyst which can give a silicone composition having good storage stability, excellent curability, and a reduced time lag between the curing temperature and the reaction rate, can be produced easily and has quality having good uniformity by production lot. SOLUTION: There is provided a hydrosilylation catalyst containing 0.1-50 wt.% (in terms of the platinum atoms) platinum catalyst, the platinum catalyst being included in a compound having a melting point between 40 and 200 deg.C and containing at least one structure or group selected among aliphatic unsaturations, carbonyls, carboxyls, and thioether groups in the molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel hydrosilylation reaction catalyst and a silicone composition containing the same.

[0002]

2. Description of the Related Art
Platinum group metal catalyzed addition reactions between aliphatic unsaturated bonds and hydrosilyl groups are utilized in many fields. Among them, platinum compounds are used as the most versatile catalyst compounds in this field, and are used as a means for crosslinking of addition-resin resins or rubber in the silicone industry, in addition to organic synthesis reactions such as synthesis of silalkane bonds. Have been. Applications include adhesives, coatings, potting agents, gels, foams, extrusion with liquid or millable rubber, compression molding or injection molding.In these fields, the shelf life is limited from the viewpoint of processability and workability. There is a need for a long, fast curing material.

[0003] Therefore, with respect to compositions utilizing this addition reaction as a crosslinking system, there have hitherto been proposed many control agents for controlling the shelf life and pot life of platinum-based catalysts, for example, benzotriazole. Compounds (JP-B-40-25069)
Publication), acetylene alcohol compounds (JP-B-44)
JP-A-31476), vinyl group-containing polysiloxane compounds (JP-B-48-10947), hydroperoxides (JP-B-57-20340), amine compounds (JP-A-63-56563) and the like. No. However, such a chemical control has a limit in the balance between the pot life and the curing speed, and it has become impossible to cope with market demands for longer storage stability and sharper curability.

[0004] From such a viewpoint, a method has been attempted in which a platinum-based catalyst is embedded in a thermoplastic resin or a silicone resin, and the catalyst is released into the silicone composition by melting the thermoplastic resin or the silicone resin with temperature. Prior literature relating to this technology is disclosed in Japanese Patent Application Laid-Open No. 49-1347.
No. 86, JP-A-58-37053 and JP-A-6
JP-A-4-51140, JP-A-2-9448, JP-A-2-14244, JP-A-5-202193, JP-A-7-196921 and the like.

However, when a catalyst is embedded in such a thermoplastic resin or silicone resin, a time lag occurs until the resin is dissolved. On the other hand, if the molecular weight distribution is not controlled, there is a disadvantage that a time lag also occurs in the dissolution temperature and there is a large variation between synthesis lots.

The present invention has been made in view of the above circumstances,
It is a curing catalyst for room-temperature or heat-curable silicone compositions, has good storage properties and excellent curability, and is easy to manufacture, with no time lag between the curing temperature and the reaction rate, and the quality of each production is constant. An object of the present invention is to provide a certain hydrosilylation reaction catalyst and a silicone composition using the same.

[0007]

Means for Solving the Problems and Embodiments of the Invention The present inventors have conducted intensive studies to achieve the above object, and as a result, they have sharp thermal melting characteristics instead of the conventional polymer thermoplastic resin. Compound, that is, the melting point is 40 to 200 ° C.
And a compound containing at least one structure or group selected from an aliphatic unsaturated bond, a carbonyl group, a carboxyl group, and a thioether group in one molecule, particularly a compound having a molecular weight of 1,000 or less. It has been found that by using a hydrosilylation reaction catalyst obtained by encapsulation or inclusion (so-called microencapsulation), it is possible to obtain a silicone composition having both good preservability and rapid curability, and the present invention. Was reached.

Accordingly, the present invention provides a catalyst comprising 0.1 to 50% by weight of a platinum-based catalyst in terms of platinum atoms, wherein the platinum-based catalyst has a melting point of 40 to 200 ° C. and has an aliphatic unsaturated bond in one molecule. , A carbonyl group, a carboxyl group, a hydrosilylation reaction catalyst encompassed by a compound containing at least one structure or group selected from thioether groups, and (A) at least two or more alkenyl groups and / or 100 parts by weight of organopolysiloxane containing two or more hydroxyl groups (B) Organohydrogenpolysiloxane containing at least two hydrogen atoms directly bonded to silicon atoms in the molecule Total of alkenyl groups and hydroxyl groups of component (A) The amount of hydrogen atoms directly connected to silicon atoms is from 0.4 to 1 mol.
(C) The above hydrosilylation reaction catalyst The platinum catalyst is used in an amount of 0.1% based on the total of the components (A) and (B).
Provided is a silicone composition comprising 1 to 1000 ppm as an essential component.

Hereinafter, the present invention will be described in more detail. As described above, the hydrosilylation reaction catalyst according to the present invention uses a platinum-based catalyst in an amount of 0.1 to 50% based on platinum atoms.
(Weight%, the same applies hereinafter), having a melting point of 40 to 200 ° C., and having at least one structure or group selected from an aliphatic unsaturated bond, a carbonyl group, a carboxyl group, and a thioether group in one molecule. A hydrosilylation reaction catalyst containing the above-mentioned platinum-based catalyst in a heat-fusible compound contained therein.

Here, in the present invention, the platinum-based catalyst is
Includes platinum alone, platinum compounds and complexes thereof containing a platinum atom as a catalytic metal. As a platinum-based catalyst,
Conventionally known ones may be used, such as platinum black, platinum chloride, chloroplatinic acid or various complexes derived therefrom.Specifically, platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, chloride A complex of platinum acid with an olefin, aldehyde, vinyl siloxane, acetylene alcohol or the like is exemplified, but a platinum complex of vinyl siloxane is preferably used.

The amount of the platinum-based catalyst used is 0.1 to 50%, preferably 0.1%, as platinum atoms, based on the entire hydrosilylation reaction catalyst after embedding (including) in a heat-fusible compound described later. When the number of platinum atoms is small, the concentration of the heat-meltable compound in the reaction system and the composition becomes relatively high, and the physical properties of the silicone composition and the like are reduced. The effect of which cannot be ignored. On the other hand, if there are too many platinum atoms, the amount of the compound to be carried will be too small, and the pot life of the addition-curable silicone composition will be short as in the case of ordinary platinum-based catalysts, and storage stability will not be obtained.

On the other hand, the heat-meltable compound is 40 to 200.
° C, preferably 40 to 150 ° C, more preferably 40 to 150 ° C.
Compounds having a melting point of 100 ° C., and compounds having a melting point of less than 40 ° C. may be melted when the temperature and room temperature are raised. Be practical. This heat-meltable compound is
One molecule contains at least one structure or group selected from an aliphatic unsaturated bond, a carbonyl group, a carboxyl group, and a thioether group, and contains an organosilyl group, an organosiloxanyl group, or an organosiloxane group. And a hydrocarbon compound.

The aliphatic unsaturated bond in the heat-fusible compound includes an aliphatic double bond represented by C ＝ C (alkenyl structure) and an aliphatic triple bond represented by C≡C (alkynyl structure). And the carbon atom having these aliphatic multiple bonds is located at the terminal of the molecule (ie,
Even if CHR = CR- or HC≡C- (R is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group), it is located inside the molecule (ie, -C
R = CR- or an internal multiple bond represented by -C≡C-). Among such compounds, those having an aromatic ring such as an aliphatic unsaturated bond and an aryl group, an aralkyl group (phenyl skeleton, naphthyl skeleton), or an arylene group (phenylene skeleton, naphthylene skeleton) in one molecule are preferable. .

The molecular weight of the heat-meltable compound is 1000
Hereinafter, those having a molecular weight of 50 to 500 are particularly preferable, and those having a high molecular weight may not have a sharp melting temperature and may not be suitable for obtaining a sharp curability which is the object of the present invention.

Examples of the heat-fusible compound used in the present invention include 2-butyne-1,4-diol, diphenylacetylene, 4-hexylresorcin, 2-vinylnaphthalene, 2-acetyl-1-tetralone, 5-diphenyloxazole, 2,5-toluquinone, 3,6-dimethyl-4-octyne-3,6-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 1,3-bis (trimethylsilyl (Ethynyl) benzene, thiochroman-4-ol and the like can be used.

The hydrosilylation reaction catalyst of the present invention is preferably obtained by contacting the above-mentioned heat-fusible compound with a platinum-based catalyst in a state where the heat-fusible compound is melted or dissolved. In the case of melting, the compound is heated to a temperature equal to or higher than the melting point of the compound. In the case of dissolution, the platinum-based catalyst is supported in a uniform or dispersed state in a solvent. This is cooled or the solvent is distilled off to solidify, whereby a solid catalyst in which the platinum-based catalyst is uniformly dispersed is obtained. In addition to these methods, these are sprayed in the form of a mist in the liquid state of melting or dissolving to solidify or remove the solvent, and spray drying to obtain fine particles (microcapsules). A method for obtaining a solid catalyst by a so-called freeze-drying method in which the solvent is cooled to a temperature lower than the solidification temperature of the solvent while being dissolved in the solvent, and the solvent is removed under reduced pressure.

The solid catalyst thus obtained may be used as a powder or may be used as a solution or dispersed again in a solvent or silicone oil. In this case, it is preferable to select a solvent that is not completely compatible with the organopolysiloxane as the main component of the composition at normal temperature (usually about 5 to 35 ° C.).

Some of the above heat-meltable compounds belong to the acetylene alcohols mentioned in the prior art, but the conventional acetylene alcohol compounds are liquid at room temperature or easily dissolved in polysiloxane. Substance. According to the present invention, a platinum compound-containing solid (at room temperature) is formed by pre-coordinating a platinum compound to these substances, and these are mechanically dispersed or dissolved in a solution during the production process, and this is used as a polysiloxane. It differs from the prior art in that it is reprecipitated and dispersed microscopically by being added to the composition to form a platinum-based catalyst contained in a compound having a melting point in the composition. Among these heat-meltable compounds that are solid at room temperature, compounds containing an aliphatic multiple bond (aliphatic double bond or triple bond) are preferred in view of changes in catalytic activity due to long-term storage. Further, aryl groups such as phenyl group, tolyl group, xylyl group, ethylphenyl group, and naphthyl group, and aralkyl groups such as benzyl group, phenylethyl group and phenylpropyl group (phenyl skeleton, Compounds which also have an aromatic ring structure such as an arylene group (a phenylene skeleton or a naphthylene skeleton) such as a naphthyl skeleton, a phenylene group, a tolylene group, a xylylene group, or a naphthylene group are suitable for use. Further, the platinum compound-containing compound of the present invention may be further included in other resins, for example, a silicone resin, a vinyl polymer, or any other substance having a softening point or melting point according to the purpose, as long as the properties of the present invention are not impaired. good.

When the hydrosilylation reaction catalyst of the present invention is used, when the silicone composition as the final product is mechanically re-dispersed with, for example, ditrol, the platinum contained in a conventional thermoplastic resin or silicone resin is used. Surprisingly, it has been confirmed that, unlike the system catalyst, the curing speed is accelerated and the storage time is not shortened. That is, when microcapsules are formed by a conventional polymer film, the catalyst is exposed when the film is destroyed by mechanical dispersion, which promotes the reaction and reduces the storage time. Since such a problem does not occur and only the reaction rate is accelerated, it has an excellent property that it is not necessary to consider the avoidance of the mechanical shearing step in the step after mixing the catalyst in the production.

As an example, the hydrosilylation reaction catalyst of the present invention can be cured to form an elastomer (rubber-like elastic body), gel, foam (sponge), etc., at room temperature or heat curable silicone composition of the following formulation. Used as a catalyst. (A) 100 parts by weight of an organopolysiloxane containing at least two or more alkenyl groups and / or two or more hydroxyl groups in the molecule (B) At least two hydrogen atoms directly bonded to silicon atoms in the molecule Organohydrogenpolysiloxane An amount in which the amount of hydrogen atoms directly bonded to silicon atoms is 0.4 to 20 moles per 1 mole of the total of the alkenyl groups and hydroxyl groups of the component (A) [however, preferably (A) The total of the number of alkenyl groups and / or hydroxy groups per component molecule and the number of hydrogen atoms (SiH groups) directly bonded to silicon atoms per component (B) molecule is 5 or more. (C) The above hydrosilylation reaction catalyst As platinum metal, 0.1 to 1000 ppm based on the total of components (A) and (B) (D) Addition inhibitor 0 to 10 parts by weight (E) Filler 0 to 200 Parts by weight Here, as the component (A), those represented by the following average composition formula R _a SiO _{(4-a) / 2} can be used. In this formula, R is substituted or unsubstituted, preferably having 1 to 10 carbon atoms,
In particular, a monovalent hydrocarbon group or a hydroxyl group of 1 to 8, for example, an alkyl group such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl, Alkenyl groups such as allyl, propenyl, butenyl, and hexenyl; aryl groups such as phenyl and tolyl; aralkyl groups such as benzyl and phenylethyl; and some or all of the hydrogen atoms bonded to carbon atoms of these groups are halogen atoms. An atom, a group substituted with a cyano group, such as chloromethyl, bromoethyl, cyanoethyl, 3,
Examples include a substituted hydrocarbon group such as 3,3-trifluoropropyl and a hydroxyl group. A is a positive number of 1.85 to 2.3, particularly 1.95 to 2.05.

In this case, in the organopolysiloxane of the component (A), the alkenyl group and the hydroxyl group are functional groups that contribute to a crosslinking reaction, and are alkenyl groups and / or hydroxyl groups relative to the entire monovalent group R bonded to a silicon atom in one molecule. Or the content of a hydroxyl group is 0.001 to 5 mol%, preferably 0.01 to 2 mol%.
It needs to be in the range of mol%. If the amount is less than 0.001 mol%, the cured molded product is weak and has no strength, and does not function as a rubber elastic body. If it is more than 5 mol%, the crosslink density is high and the cured product becomes brittle.

The viscosity of the organopolysiloxane is not particularly limited, but is usually 100 to 1,000,000 c.
p, preferably about 100 to 100,000 cp, and more preferably about 100 to 10,000 cp. A viscosity of 100 to 5,000 cp is particularly recommended as a viscosity suitable for lowering the viscosity. All of these can be obtained by a conventionally known manufacturing method.

As a functional group contributing to the crosslinking reaction, a hydroxyl group is preferably bonded only to silicon atoms at both ends of the molecular chain, and an alkenyl group is preferably bonded to any silicon atom at the molecular chain terminal or in the middle of the molecular chain. It may be bonded to an atom or may be bonded to both atoms.However, in terms of the properties of the cured product, at least an alkenyl group bonded to silicon atoms at both ends of the molecular chain is used. It is preferable that it contains.

The organopolysiloxane of the component (A) is
In general, the main chain is basically composed of repeating diorganosiloxane units, and has a linear structure in which both molecular chain terminals are blocked with a triorganosilyl group or a diorganohydroxysilyl group. The portion may contain a branched structure, or may be a cyclic body.

Specific examples of the component (A) include the following.

[0026]

Embedded image

Although R has the same meaning as described above, a group other than an alkenyl group and a hydroxyl group is particularly preferable. Also,
x is 1 to 5000, preferably 10 to 2000, and y is 1
~ 200, preferably 1-100, x + y is 10-50
00, preferably about 15 to 2,000. z is 2 or 3.

As the component (B), one molecule represented by the following average composition formula R ¹ _b H _c SiO _{(4-bc) / 2} contains at least two hydrogen atoms bonded to silicon atoms (ie, SiH groups). And preferably three or more organohydrogenpolysiloxanes. Here, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms, similar to the above R, and specifically contains the same groups as those exemplified for R. And preferably those containing no aliphatic unsaturated bonds. Also, b is 0.7 to 2.2, preferably 1 to 2, c is 0.005 to 1.2, preferably 0.01 to 1, and b + c = 0.8 to 3, preferably 1 to 1.
It is a positive number that satisfies 2.4.

The organohydrogenpolysiloxane of the component (B) may have any molecular structure such as a linear, cyclic, branched, or resinous resin having a three-dimensional network structure. The atom (SiH group) may be located either at the terminal of the molecular chain or in the middle of the molecular chain, or may be located at both. The number of silicon atoms (or degree of polymerization) in the molecule is 2 to 400, preferably 4 to 1
It may be about 50.

In this case, the amount of the SiH group in the component (B) is 0.4 to 20 mol, preferably 0.1 to 10 mol, per 1 mol of the total of the alkenyl group and the hydroxyl group in the component (A).
It is in the range of 4 to 10 moles, more preferably 0.5 to 2.5 moles, but when a foam is obtained, it is preferably 2 to 2 moles based on 1 mole of the total of all alkenyl groups and hydroxyl groups in the composition.
The amount is preferably 0 mol.

It is preferable that the total of the number of alkenyl groups and / or hydroxyl groups per molecule of component (A) and the number of SiH groups per molecule of component (B) be 5 or more. After the conversion or dehydrogenation reaction, a three-dimensional crosslinked structure is reliably formed, and curing takes place, thereby making it possible to obtain an elastomer.
The component (B) has a alkenyl group and / or a hydroxyl group in the component (A) in which the SiH group is outside the above range,
A sufficient crosslinked structure is not formed. The amount of the component (C) (the hydrosilylation reaction catalyst) to be added is 0.1% based on the total weight of the components (A) and (B) as the platinum metal in the component (C).
1 to 1000 ppm, and the amount of platinum metal is (A)
If the total amount of (B) is less than 0.1 ppm, the curing reaction does not proceed sufficiently, and if it exceeds 1000 ppm, it is economically disadvantageous.

In order to control the hydrosilylation reaction, the silicone composition contains, as component (D), 0 to 10 parts by weight, preferably 0.0 to 10 parts by weight, per 100 parts by weight of component (A).
From 0.01 to 5 parts by weight of a vinyl group-containing organopolysiloxane, acetylene alcohol, triallyl isocyanurate, alkyl maleate, hydroperoxide,
If necessary, an addition reaction controlling agent selected from the group consisting of tetramethylethylenediamine, benzotriazole and a mixture thereof may be added. These compounds are
A free platinum-based catalyst derived from a trace amount of the heat-fusible compound contained in the component (C) during the long-term storage period as one component or added to ensure initial foaming when the present composition is used as a foam. It is effective for controlling platinum compounds.

In order to increase the physical strength and hardness of the silicone elastomer, fine powdered calcined silica, finely powdered precipitated silica, quartz powder, alumina, aluminum hydroxide, carbon black, silver powder, Fillers such as gold powder, magnesium compounds, zinc white, zinc carbonate and the like can be added in an amount of 0 to 800 parts by weight, preferably 1 to 200 parts by weight, per 100 parts by weight of the component (A).

Further, as long as the object of the present invention is not impaired, a substance containing one or more groups selected from an alkoxysilyl group, an epoxy group, a hydrosilyl group, an acryl group, a hydroxysilyl group, etc. The mixture can be used as an adhesive component, non-reactive organopolysiloxanes and the like can be blended as a diluent, a viscosity regulator and a hardness regulator, and an inorganic pigment such as cobalt blue and a coloring agent such as an organic dye such as azo and anthracene. It is also possible to add heat-resistant and flame-retardant improvers such as cerium oxide, zinc carbonate, manganese carbonate, red iron oxide, titanium oxide and carbon black.

The curing conditions of the above silicone composition can be generally at 60 to 200 ° C. for about 2 to 20 minutes. When curing at room temperature is desired, the addition of a solvent that dissolves the platinum-containing catalyst promotes the hydrosilylation reaction and / or dehydrogenation reaction, and cures at a low temperature without heating. It is possible to do.

[0036]

Industrial Applicability The hydrosilylation reaction catalyst of the present invention provides a silicone composition which has good storage stability and excellent curability, hardly causes a time lag in curing temperature and reaction rate, and is easy to produce. Quality is constant.

[0037]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples.

Synthesis Example 1 To 5 g of 3,6-dimethyl-4-octyne-3,6-diol (melting point: 54 ° C.) was added 5 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid. After heat treatment at 80 ° C. for 1 hour, stripping and cooling, a solid hydrosilylation reaction catalyst (platinum atom content: 0.5% by weight) was produced.

Synthesis Example 2 5 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid was added to 2.5 g of 3,6-dimethyl-4-octyne-3,6-diol (melting point: 54 ° C.). In addition, heat treated at 80 ° C for 1 hour,
After stripping, it is cooled and rolled at 25 ° C. with 2.5 g of dimethylpolysiloxane having a viscosity of 1000 cS to produce a paste-like hydrosilylation reaction catalyst (platinum atom content: 0.5% by weight). did.

[Synthesis Example 3] To 5 g of 3,6-dimethyl-4-octyne-3,6-diol (melting point: 54 ° C.), 10 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid was added. Heat treatment was carried out at 80 ° C. for 1 hour, stripping, cooling, and spray drying were performed to produce a fine powdery hydrosilylation reaction catalyst (platinum atom content: 0.7% by weight).

Synthesis Example 4 To 5 g of thiochroman-4-ol (melting point 69 ° C.) was added 5 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid, and the mixture was heated at 80 ° C. in the presence of 5 g of toluene as a solvent. The mixture is heat-treated for 1 hour, emulsified with 0.5 g of a polyglycerin-based surfactant in water, and then filtered to obtain a finely powdered hydrosilylation reaction catalyst (platinum atom content: 0.5% by weight). Manufactured.

Synthesis Example 5 To 5 g of 2-acetyl-1-tetralone (melting point 56 ° C.) was added 5 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid.
Heat treatment at 80 ° C for 1 hour, cool after stripping,
Solid hydrosilylation reaction catalyst (platinum atom content: 0.5
% By weight).

Synthesis Example 6 2,4,7,9-Tetramethyl-5-decyne-4,7-diol (melting point: 44 ° C.)
g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid, and heat-treated at 80 ° C. for 1 hour together with 6 g of a trisiloxane containing a phenyl group. A catalyst (platinum atom content: 0.2% by weight) was produced.

Synthesis Example 7 To 5 g of 1,3-bis (trimethylsilylethynyl) benzene (melting point: 58 ° C.) was added 5 g of a toluene solution of a siloxane complex containing a vinyl group derived from chloroplatinic acid. After heat treatment for an hour, stripping and cooling, a solid hydrosilylation reaction catalyst (platinum atom content: 0.5% by weight) was produced.

Example 1 100 g of dimethylpolysiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with a dimethylvinylsiloxy group, and methylhydrogenpolysiloxane 1 represented by the following average molecular formula (1) 0.8 g, 10 g of fumed silica having a surface area treated with dimethyldichlorosilane (BET method) of 200 m ² / g, and the hydrosilylation reaction catalyst of Synthesis Example 5 mixed at a platinum concentration of 30 ppm. A pot life of 72 hours or more was given, and the composition was completely cured by heating at 105 ° C. for 15 minutes to obtain a rubber-like elastic body.

[0046]

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Example 2 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with dimethylvinylsiloxy groups, the average degree of polymerization was 50, and both ends were blocked with trimethylsilyl groups. Polymethyl hydrogen siloxane (SiH group;
9 g, 5 g of polydimethylsiloxane having both ends capped with hydroxyl groups and having an average degree of polymerization of 20, and a surface area treated with dimethyldichlorosilane (BET).
Law) is 200 meters ² / g fumed silica 10 g, Synthetic Example 1
Of the hydrosilylation reaction catalyst synthesized in
When mixed at a temperature of 105 ° C. for 5 minutes, the mixture was completely cured as a sponge-like foam having uniform microcells (1 mm or less) by heating at 105 ° C. for 5 minutes, and provided a pot life of 100 hours or more at 25 ° C. .

Example 3 100 g of polydimethylsiloxane having a viscosity of 20,000 cS at 25 ° C., both ends of which are blocked with a hydroxyl group, 100 g of polymethylhydrogen having an average degree of polymerization of 50 and both ends blocked with a trimethylsilyl group Gensiloxane (SiH group; 0.0158 mol /
g) 9 g, average degree of polymerization of 20 having both ends blocked with hydroxyl groups
5 g of polydimethylsiloxane, surface area of which was treated with dimethyldichlorosilane (BET method) was 200 m ² /
g of the fumed silica (10 g) and the hydrosilylation reaction catalyst synthesized in Synthesis Example 6 were mixed at a platinum concentration of 30 ppm, and were completely cured by heating at 120 ° C. for 10 minutes.
A sponge-like foam having uniform fine cells (1 mm or less) was obtained. Also, a pot life of 100 hours or more was given at 25 ° C.

Example 4 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which were blocked with dimethylvinylsiloxy groups, the average degree of polymerization was 50, and both ends were blocked with trimethylsilyl groups. Polymethyl hydrogen siloxane (SiH group;
9 g, 5 g of polydimethylsiloxane having both ends capped with hydroxyl groups and having an average degree of polymerization of 20, and a surface area treated with dimethyldichlorosilane (BET).
Method) is 200 m ² / g fumed silica 10 g, Synthesis Example 7
Of the hydrosilylation reaction catalyst synthesized in
The mixture was heated to 105 ° C. for 10 minutes and completely cured as a sponge-like foam having uniform fine cells (1 mm or less) by heating at 105 ° C. for 10 minutes, and was given a pot life of 20 hours at 25 ° C.

Example 5 100 g of polydimethylsiloxane having a molecular chain end blocked with a dimethylvinylsiloxy group, having one branch point in the molecule and having a viscosity of 1000 cS at 25 ° C., and having an average degree of polymerization of 30 Polydimethylsiloxane having both ends blocked with a dimethylhydrogensilyl group (SiH group; 0.085 mol / 100 g) 6
g, the hydrosilylation reaction catalyst synthesized in Synthesis Example 3 was mixed to a platinum concentration of 30 ppm.
The composition was completely cured as a gel-like elastic body by heating at 15 ° C. for 15 minutes, and gave a pot life of 6 hours at 25 ° C.

Example 6 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with dimethylvinylsiloxy groups, the average degree of polymerization was 50, and both ends were blocked with trimethylsilyl groups. Polymethyl hydrogen siloxane (SiH group;
9 g, 5 g of polydimethylsiloxane having both ends capped with hydroxyl groups and having an average degree of polymerization of 20, and a surface area treated with dimethyldichlorosilane (BET).
Method) is 200 m ² / g fumed silica 10 g, Synthesis Example 4
Of the hydrosilylation reaction catalyst synthesized in
When mixed at a temperature of 105 ° C. for 5 minutes, the mixture was completely cured as a sponge-like foam having uniform microcells (1 mm or less) by heating at 105 ° C. for 5 minutes, and provided a pot life of 100 hours or more at 25 ° C. .

Comparative Example 1 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with dimethylvinylsiloxy groups, 100 g of methyl hydrogen polysiloxane represented by the above average molecular formula (1) 1.8 g, 10 g of fumed silica having a surface area (BET method) of 200 m ² / g treated with dimethyldichlorosilane, and a vinyl group-containing siloxane complex derived from chloroplatinic acid were mixed to a platinum concentration of 30 ppm. When left at 25 ° C., it was cured in one minute.

Comparative Example 2 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with dimethylvinylsiloxy groups, 100 g of methyl hydrogen polysiloxane represented by the above average molecular formula (1) 1.8 g, 10 g of fumed silica having a surface area treated with dimethyldichlorosilane having a surface area (BET method) of 200 m ² / g, and 5 g of n-octacosan (melting point: 64 ° C.)
5 g of a 0.1 wt% platinum vinyl group-containing siloxane complex
, And heat-treated at 80 ° C. for 1 hour. After stripping, the resulting hydrosilylation reaction catalyst was cooled to a platinum concentration of 30 pp.
m, and the mixture was left at 25 ° C. and cured in 1 minute.

Comparative Example 3 Both ends of the molecular chain were dimethyl vinyl
30000 cS at 25 ° C.
100 g of polydimethylsiloxane having viscosity,
Methyl hydrogen poly represented by average molecular formula (1)
1.8 g of siloxane, dimethyldichlorosilane on the surface
The treated surface area (BET method) is 200m^Two/ G haze
10 g of silica, the following average composition formula (C₆H_Five) SiO_3/2: 80 mol% (C H_Two= CH) SiO_3/2: 5 g of silicone resin having a melting point of 50 to 85 ° C. represented by 20 mol%
5 g of a 0.1 wt% platinum vinyl group-containing siloxane complex
The hydrosilylation reaction catalyst obtained by incorporating
When mixed at 0 ppm, 5 hours at 25 ° C
But it was heated at 120 ° C for 20 minutes
Cured.

Comparative Example 4 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which are blocked with dimethylvinylsiloxy groups, 100 g of methylhydrogenpolysiloxane represented by the above average molecular formula (1) 1.8 g, 10 g of fumed silica having a surface treated with dimethyldichlorosilane having a surface area (BET method) of 200 m ² / g, the following average composition formula (C ₆ H ₅ ) SiO _3/2 : 70 mol% (C ₃ H ₇ ) 5 g of silicone resin having a melting point of 35 to 70 ° C., expressed by SiO _3/2 : 30 mol%
5 g of a 0.1 wt% platinum vinyl group-containing siloxane complex
The hydrosilylation reaction catalyst obtained by incorporating
When the mixture was adjusted to 0 ppm, it was completely cured at 100 ° C. for 5 minutes, but only a 15-minute pot life at 25 ° C. was obtained.

Comparative Example 5 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which were blocked with dimethylvinylsiloxy groups, the average degree of polymerization was 50, and both ends were blocked with trimethylsilyl groups. Polymethyl hydrogen siloxane (SiH group;
9 g, 5 g of polydimethylsiloxane having both ends capped with hydroxyl groups and having an average degree of polymerization of 20, and a surface area treated with dimethyldichlorosilane (BET).
Method), 10 g of fumed silica of 200 m ² / g and a vinyl-containing siloxane complex derived from chloroplatinic acid were mixed to a platinum concentration of 30 ppm and left at 25 ° C. for 1 minute to cure. Was.

Comparative Example 6 100 g of polydimethylsiloxane having a viscosity of 30,000 cS at 25 ° C., both ends of which were blocked with dimethylvinylsiloxy groups, the average degree of polymerization was 50, and both ends were blocked with trimethylsilyl groups. Polymethyl hydrogen siloxane (SiH group;
9 g, 5 g of polydimethylsiloxane having both ends capped with hydroxyl groups and having an average degree of polymerization of 20, and a surface area treated with dimethyldichlorosilane (BET).
Law) is 200 meters ² / g fumed silica 10 g, 3,5-
Dimethyl-1-hexyn-3-ol (melting point -68 ° C)
0.02 g of a siloxane complex containing a vinyl group derived from chloroplatinic acid was mixed at a platinum concentration of 30 ppm to give a pot life of 24 hours at 25 ° C.
When the composition was cured at 05 ° C. for 5 minutes, a very strong tackiness was left and the curing was insufficient.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C08L 83/05 C08L 83/05 83/06 83/06 83/07 83/07 (72) Inventor Hironobu Muramatsu Matsuida-machi, Daishihito, Usui-gun, Gunma Prefecture No. 1-10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Technology Laboratory

Claims (5)

[Claims] 1. A platinum-based catalyst containing 0.1 to 5 platinum atoms.
0% by weight, and the platinum-based catalyst has a melting point of 40 to 200 ° C.
A hydrosilylation reaction catalyst comprising a compound having at least one structure or group selected from an aliphatic unsaturated bond, a carbonyl group, a carboxyl group, and a thioether group in one molecule. 2. The molecular weight of a compound having a melting point between 40 and 200 ° C. and containing at least one structure or group selected from aliphatic unsaturated bonds, carbonyl groups, carboxyl groups and thioether groups in one molecule. The hydrosilylation reaction catalyst according to claim 1, wherein is less than or equal to 1,000. 3. A compound having a melting point of 40 to 200 ° C. and containing at least one structure or group selected from an aliphatic unsaturated bond, a carbonyl group, a carboxyl group and a thioether group in one molecule, and platinum. The hydrosilylation reaction catalyst according to claim 1 or 2, which is obtained by including a step of contacting a system catalyst with the compound in a molten or dissolved state. 4. A step of bringing a compound having a melting point of 40 to 200 ° C. and containing an aliphatic unsaturated bond and an aromatic ring in one molecule into contact with a platinum-based catalyst in a molten or dissolved state of the compound. The hydrosilylation reaction catalyst according to claim 3, which is obtained by including the compound. (A) 100 parts by weight of an organopolysiloxane containing at least two or more alkenyl groups and / or two or more hydroxyl groups in the molecule; and (B) a hydrogen atom directly bonded to a silicon atom in the molecule. Organohydrogenpolysiloxane containing at least 2 components The amount of hydrogen atoms directly bonded to silicon atoms is 0.4 to 1 mol based on the total 1 mol of alkenyl groups and hydroxyl groups of component (A).
(C) The hydrosilylation reaction catalyst according to any one of claims 1 to 4, wherein the platinum metal is 0.1 mol based on the total of the components (A) and (B).
A silicone composition comprising 1 to 1000 ppm as an essential component.