JP3521590B2 - Catalyst composition for addition reaction and curable organopolysiloxane composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organosilicon compound such as an organopolysiloxane having an aliphatic unsaturated group and an organohydrogenpolysiloxane containing an active hydrogen atom such as an SiH group (that is, a hydrosilyl group). Regarding a composition for a catalyst used in an addition reaction with an organosilicon compound, particularly suitable as a curing catalyst used for curing an addition reaction-curing organopolysiloxane composition, which has an excellent pot life near room temperature and a high temperature. Relates to a catalyst composition for addition reaction having excellent curing properties and a curable organopolysiloxane composition containing the catalyst composition.

[0002]

2. Description of the Related Art Platinum alkenyl siloxane complexes produced by the reaction of alkenyl group-containing siloxanes with chloroplatinic acid and the like have high catalytic activity and are used for addition reaction-curing organopolysiloxane compositions. It is useful as a curing catalyst used for curing (Japanese Patent Publication No. 46-28795, Japanese Patent Publication No. 51-8926, and Japanese Patent Publication No. 55-423). Further, when the platinum alkenylsiloxane complex is added to an organopolysiloxane composition composed of an organopolysiloxane having an aliphatic unsaturated group and an organohydrogenpolysiloxane having a SiH group, a curing reaction occurs instantaneously. Therefore, when using it, store it under normal storage conditions, for example 25 ° C.
A large amount of platinum catalyst inhibitor is required to prolong the pot life at room temperature in the vicinity.

Conventionally, polymethylvinylsiloxane cyclic compounds and acetylene compounds have been known as inhibitors of these platinum-based catalysts. However, if a large amount of these is used, the crosslink density is affected and the properties of the cured product are impaired. There was a problem of being lost. In order to solve this problem, it has been desired to develop a catalyst for addition reaction which has an excellent pot life near room temperature and an excellent curing property at high temperatures.

[0004]

Means for Solving the Problems and Modes for Carrying Out the Invention As a result of intensive studies to solve the above-mentioned conventional problems, the present inventor has found that an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane is used as a ligand. 1 to 3 in each molecule of a platinum complex and a hydrogen atom bonded to a silicon atom.
Organohydrogen siloxane or organohydrogensyl alkylene compound is contained in an amount of 1 mole of platinum atom in the platinum complex, and the silicon atom-bonded hydrogen atom (that is, , SiH
It was found that a catalyst composition effective for a hydrosilylation addition reaction, which is excellent in long-term storage stability and hardly deteriorates even at high temperatures, can be obtained by contacting and mixing such that the amount of the base group is 10 mol or more. A composition obtained by uniformly blending an alkenyl group-containing organopolysiloxane as a main agent and an organohydrogenpolysiloxane having at least two, preferably three or more silicon-bonded hydrogen atoms in a molecule as a crosslinking agent. Has been confirmed to have an excellent pot life at around room temperature and an excellent curing property at high temperatures, and has completed the present invention.

Therefore, according to the present invention, (A) a platinum complex having an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand, and (B) a hydrogen atom bonded to a silicon atom in an amount of 1 to 1 per molecule. Consisting of 3 hydrogen-containing organohydrogensiloxanes or organohydrogensyl alkylene compounds, and 1 mol of platinum atoms in component (A) has 10 or more mols of silicon-bonded hydrogen atoms in component (B). A catalyst composition for addition reaction obtained by mixing the above components is provided. The present invention also relates to an organopolysiloxane containing an organopolysiloxane containing at least two alkenyl groups in one molecule and an organohydrogenpolysiloxane containing at least two silicon-bonded hydrogen atoms in one molecule. The composition contains (A) a platinum complex having an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand, and (B) an organopolysiloxane containing 1 to 3 hydrogen atoms bonded to a silicon atom in one molecule. A hydrogen siloxane or an organohydrogensyl alkylene compound, and the amount of silicon atom-bonded hydrogen atoms in the component (B) is 10 moles or more per mole of the platinum atom in the component (A). Contact at a temperature of 50 ° C for 1 to 4 hours,
A curable organopolysiloxane composition comprising a catalyst composition for addition reaction obtained by uniformly mixing the composition.

The present invention will be described in more detail below. In the catalyst composition for addition reaction of the present invention, a platinum complex having an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand is used as the component (A).

The platinum complex of the component (A) is known per se in the art. For example, JP-B-46-28795, JP-B-51-8926, and JP-B-55-423.
JP-A-56-136655 and Japanese Patent Application Laid-Open No. 56-136655 disclose a platinum complex having an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand.

The alkenyl group in the alkenyl group-containing organosilane or alkenyl group-containing organosiloxane as a ligand is, for example, a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, or the like. Examples of the lower alkenyl group of about 2 to 4 include a substituent bonded to a silicon atom other than the alkenyl group in the organosilane or organosiloxane, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. Group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, etc., alkyl group having about 1 to 8 carbon atoms, phenyl group, tolyl group, xylyl group, naphthyl group Number of carbon atoms in groups such as 6-10 1 to 4 carbon atoms such as aryl group, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, tert-butoxy group, methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group Alkoxy groups or alkoxy-substituted alkoxy groups, etc. are mentioned to the extent that among these, vinyl groups are preferable as alkenyl groups from the viewpoints of ease of synthesis, stability of the complex, etc., and substituents other than alkenyl groups Of these, a methyl group and a phenyl group are preferable, and a methyl group is particularly preferable.

In this alkenyl group-containing organosilane or alkenyl group-containing organosiloxane, the number of alkenyl groups bonded to a silicon atom in one molecule is preferably 2 or more, particularly 2 to 4.

The alkenyl group-containing organosiloxane has 2 to 8 silicon atoms, particularly 2 to 2 silicon atoms.
A linear or cyclic low-polymerization degree siloxane oligomer of about 4 is preferably used.

Specifically as the alkenyl group-containing organosilane or the alkenyl group-containing organosiloxane,
Tetravinylsilane, trivinylmethylsilane, trivinylphenylsilane, trivinylmethoxysilane, trivinylethoxysilane, triallylmethylsilane, triallylphenylsilane, divinyldimethylsilane, divinyldiphenylsilane, divinylmethylethoxysilane, divinylmethylmethoxysilane , Divinyldiethoxysilane, divinyldimethoxysilane, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,
3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane, 1,3,5,7-tetravinyl-1,
Examples include 3,5,7-tetramethylcyclotetrasiloxane and the like.

The platinum complex having the alkenyl group-containing organosilane or the alkenyl group-containing organosiloxane as the component (A) as a ligand can be produced by a conventionally known method, for example, chloroplatinic acid (H ₂ PtCl ₆ ). Or a platinum compound and an alkenyl group-containing organosilane or alkenyl group-containing organosiloxane in an amount of about 4 to 6 times the molar amount thereof in the presence of a diluent such as ethanol or a neutralizing agent such as sodium hydrogen carbonate. 60 to 8
It can be obtained by reacting at about 0 ° C. for 2 to 6 hours.

The component (B) of the present invention is an organohydrogensiloxane or an organohydrogensylalkylene compound having 1 to 3 hydrogen atoms bonded to silicon atoms (ie, SiH groups) in one molecule. It is an essential component for stabilizing the platinum complex of the component (A).

[0014] The organohydrogenpolysiloxane or organohydrogen sill alkylene compounds, for example, the following average compositional formula _{(I): R p H q} SiZ (4-p-q) / 2 (I) ( wherein, R Is an unsubstituted or substituted monovalent hydrocarbon group, Z is an oxygen atom or a lower alkylene group, p is 0 <p <3,
q is a number satisfying 0 ≦ q ≦ 2 and 1 ≦ p + q ≦ 3). The structure of such a compound is not particularly limited and may be linear, branched or cyclic.

In the average composition formula (I), suitable examples of R include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group and hexyl group. Groups, octyl groups, decyl groups, dodecyl groups, and other alkyl groups; cyclopentyl groups, cyclohexyl groups, cyclobutyl groups, and other cycloalkyl groups; phenyl groups, tolyl groups, xylyl groups,
Aryl groups such as naphthyl groups; aralkyl groups such as benzyl groups, phenylethyl groups, phenylpropyl groups; and some or all of the hydrogen atoms of these hydrocarbon groups are halogen atoms such as chlorine, fluorine and bromine, cyano groups, etc. A group substituted with, for example, a chloromethyl group, a trifluoropropyl group,
Halogenated hydrocarbon groups such as chlorophenyl group, dibromophenyl group, dibromophenyl group, tetrachlorophenyl group, diflurophenyl group, α-cyanoethyl group, β
-A cyanoalkyl group such as a cyanopropyl group and a γ-cyanopropyl group, which is usually an unsubstituted or substituted 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms excluding an aliphatic unsaturated bond. A valent hydrocarbon group can be mentioned.

In the above average composition formula, Z is an oxygen atom or a lower alkylene group, and examples of such a lower alkylene group include a methylene group, an ethylene group, a trimethylene group, a methylmethylene group, a methylethylene group and a tetramethylene group. And those having 6 or less carbon atoms such as hexamethylene group, preferably those having 2 to 4 carbon atoms.

In the organohydrogensiloxane or the organohydrogensylalkylene compound as the component (B), the number of silicon atoms (or the degree of polymerization) in one molecule is 2 to 50, particularly 2 to 20, and especially 2 to 2.
The thing of about 10 is used suitably.

Further, it is necessary that the number of hydrogen atoms bonded to silicon atoms in one molecule (ie, SiH group) is 1 to 3, and an organo group having four or more silicon atom-bonded hydrogen atoms in one molecule. When hydrogen siloxane or an organohydrogensyl alkylene compound is used (A)
Foams or gels when mixed with the ingredients.

Specific examples of the component (B) include those exemplified below.

[0020]

[Chemical 1] (However, n is an integer of 1 to 50, Me is a methyl group,
Ph represents a phenyl group. )

The amount of the component (B) blended is such that the amount of silicon atom-bonded hydrogen atoms (that is, SiH groups) in the component (B) is 10 times the molar amount of platinum in the component (A). It is necessary to make the amount equal to or more than that, and usually 10 to 1000 times equivalent, preferably 200 to 500 times equivalent. If this molar ratio is less than 10 times equivalent, sufficient stability may not be obtained, and if it exceeds 1000 times equivalent, the catalytic activity may decrease.

The catalyst composition of the present invention is produced by bringing the above-mentioned components (A) and (B) into contact with each other at room temperature of, for example, 0 to 30 ° C. or higher and for 1 to 4 hours to uniformly mix them. However, if the temperature is too high, foaming occurs and the platinum complex precipitates as platinum black. Therefore, it is preferable to contact and mix at usually 50 ° C or lower, particularly 40 ° C or lower.

The catalyst composition for addition reaction thus obtained is used as a catalyst for a hydrosilylation reaction and can be incorporated into a known addition reaction-curing organopolysiloxane composition.

Usually, this addition reaction-curable organopolysiloxane composition comprises an organopolysiloxane containing at least two alkenyl groups in one molecule and at least two, preferably three or more silicon atoms in one molecule. This composition contains an organohydrogenpolysiloxane containing a bonded hydrogen atom (that is, SiH group), and known components such as various fillers can be added to this composition at a usual dose.

Here, the alkenyl group-containing organopolysiloxane is a known organopolysiloxane used as a main raw material of a usual addition-curable silicone rubber, and is 60 to 50,000,000 cp (centipoise) at 25 ° C., particularly 100 to 5,000,000 cp. A composition represented by the general composition formula: R ¹ _a SiO 2 _{(4-a) / 2} having a viscosity of the order of magnitude can be used.

Here, R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, especially 1 to 8 carbon atoms, which is bonded to a silicon atom, such as a methyl group, an ethyl group, Alkyl groups such as propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, decyl group; vinyl group, allyl group, propenyl group, isopropenyl group Group, butenyl group, isobutenyl group,
Alkenyl groups such as hexenyl group; aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups such as benzyl group, phenylethyl group, phenylpropyl group; and some hydrogen atoms of these hydrocarbon groups Is a halogen atom such as chlorine, fluorine or bromine, a group substituted with a cyano group, for example, a chloromethyl group, a bromoethyl group,
Examples thereof include trifluoropropyl group and cyanoethyl group. The unsubstituted or substituted monovalent hydrocarbon groups may be the same or different, but it is necessary that they contain at least two alkenyl groups in the molecule, and preferably they are bonded to a silicon atom. 0.01 to ¹ of the substituent R ¹
It generally contains 0 mol%, particularly about 0.05 to 5 mol% of alkenyl groups. Also, a is 1.9 ≦ a
It is a positive number satisfying ≦ 2.25, preferably 1.95 ≦ a ≦ 2.1.

The substituent bonded to the silicon atom may be basically any of the above, but the alkenyl group is preferably a vinyl group or an allyl group, and the other substituents are a methyl group or a phenyl group. Introduction is desirable.

The organopolysiloxane may have a linear, branched, or cyclic molecular structure, but the main chain is usually basically represented by R ¹ ₂ SiO _2/2. Consisting of repeating diorganosiloxane units,
In general, both ends of the molecular chain are linear diorganopolysiloxanes capped with triorganosiloxy groups represented by R ¹ ₃ SiO _1/2 .

The alkenyl group may be bonded to either a silicon atom at the terminal of the molecular chain, a silicon atom in the middle of the molecular chain, or both, but the curing rate and cured product From the viewpoint of physical properties such as mechanical strength, it is preferable that the alkenyl groups are bonded to both ends of the molecular chain.

Such an organopolysiloxane can be produced by a known method and can be obtained by carrying out an equilibration reaction of an organocyclopolysiloxane and a hexaorganodisiloxane in the presence of an alkali or acid catalyst. .

The organohydrogenpolysiloxane reacts with the above-mentioned alkenyl group-containing organopolysiloxane and acts as a cross-linking agent, and its molecular structure is not particularly limited, and is conventionally produced, for example, linear, Various materials such as a resin material having a cyclic structure, a branched structure or a three-dimensional network structure can be used, but at least 2, preferably 3 or more hydrogen atoms bonded to one silicon atom (ie, SiH group).

This organohydrogenpolysiloxane usually has a general compositional formula: R ² _b H _c SiO ^2.
What is represented by _{(4-bc) / 2} can be used. Here, R ² is a carbon number 1 excluding unsaturated bond of resin group.
-10, especially a C1-C8 unsubstituted or substituted monovalent hydrocarbon group, and the same groups as the groups other than the alkenyl group for R ¹ can be exemplified. Also, b and c are 0.6 <b <2.2, 0.002 ≦ c <2, and
0.8 <b + c ≦ 3, preferably 1.5 ≦ b ≦ 2.0,
It is a positive number that satisfies 0.01 ≦ c ≦ 1 and 1.5 <b + c ≦ 2.7.

The organohydrogenpolysiloxane has a viscosity at 25 ° C. of usually 0.5 to 500 cp, especially 1 to 300 cp, and the number of silicon atoms (or the degree of polymerization) in one molecule is 2 to 250, especially It corresponds to about 4 to 100.

Examples of such an organohydrogenpolysiloxane include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7. Siloxane oligomers such as 9-pentamethylcyclopentasiloxane,
Molecular chain both ends trimethylsiloxy group blocked methyl hydrogen polysiloxane, molecular chain both ends trimethylsiloxy group blocked dimethylsiloxane-methyl hydrogen siloxane copolymer, molecular chain both ends silanol group blocked methyl hydrogen polysiloxane, molecular chain both ends Silanol group-blocked dimethyl siloxane / methyl hydrogen siloxane copolymer, molecular chain both ends dimethyl hydrogen siloxy group blocked dimethyl polysiloxane, molecular chain both ends dimethyl hydrogen siloxy group blocked methyl hydrogen polysiloxane, molecular chain both ends dimethyl hydro Jenshirokishi group dimethylsiloxane-methylhydrogensiloxane copolymer siloxane polymer ^consists _R 2 2 _{(H) SiO 1/2} units and _{SiO 4/2} units Optionally ^R ₂ 3 _{SiO 1/2} ^{units, R} _{2 2}
SiO _2/2 unit, R ² (H) SiO _2/2 unit,
(H) Examples include silicone resins and the like that may contain SiO _3/2 units or R ² SiO _3/2 units and the like (wherein R ² has the same meaning as described above).

The amount of the organohydrogenpolysiloxane blended is such that the number of moles of hydrogen atoms (SiH groups) bonded to silicon atoms in the organohydrogenpolysiloxane is the same as the alkenyl group-containing organopolysiloxane. 0.4 to 5 in molar ratio to 1 mol
It is an equivalent amount, and preferably in the range of 0.8 to 2 equivalents. If this molar ratio is less than 0.4 equivalent, the crosslink density becomes too low, which adversely affects the heat resistance of the cured silicone rubber. If it is more than 5 equivalents, a problem of foaming due to dehydrogenation reaction or heat resistance may occur. It may adversely affect the sex.

Such an organohydrogenpolysiloxane can be produced by a known method, for example, octamethylcyclotetrasiloxane and / or tetramethylcyclotetrasiloxane and hexamethyldisiloxane which can serve as an end group, or 1,3. -Dihydro-
A compound containing a triorganosiloxy unit or a diorganohydrogensiloxy unit such as 1,1,3,3-tetramethyldisiloxane and -1 in the presence of a catalyst such as sulfuric acid, trifluoromethanesulfonic acid or methanesulfonic acid
It can be easily obtained by equilibrating at a temperature of about 0 ° C to + 40 ° C.

The composition of the present invention has a specific surface area of 50 to 1 such as fumed silica and precipitated silica as a reinforcing filler.
Fine silica powder of about 000 m ² / g (BET method) can be blended, non-reinforcing fillers such as quartz powder, diatomaceous earth and calcium carbonate, inorganic pigments such as cobalt blue, and colorants such as organic dyes. , Cerium oxide, zinc carbonate,
Manganese carbonate, red iron oxide, titanium oxide, heat resistance improver such as carbon black, flame retardant improver and adhesion improver, or triallyl isocyanurate, alkyl maleate, acetyl alcohols and their silanes, siloxane modified products, It is permissible to add a conventionally known addition reaction control agent selected from the group consisting of hydroperoxide, tetramethylethylenediamine, benzotriazole and mixtures thereof.

When the catalyst composition of the present invention is added to the addition-curable organopolysiloxane composition, the compounding amount is a catalytic amount, preferably in the composition as the weight of platinum atom, particularly 1 to 500 ppm, especially 3 based on the total weight of the alkenyl group-containing organopolysiloxane and the organohydrogenpolysiloxane.
It is about 100 ppm.

[0039]

The catalyst composition for addition reaction of the present invention comprises an organosilicon compound such as an organopolysiloxane having an aliphatic unsaturated group and an organohydrogenpolysiloxane having an active hydrogen atom such as a SiH group. It is effective as a catalyst for accelerating the hydrosilylation addition reaction with a silicon compound, and when it is added to an addition reaction-curing organopolysiloxane composition, it has an excellent pot life at around room temperature (pot life) compared to conventional catalysts. And has an effect of exhibiting excellent curing characteristics at high temperature.

[0040]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples. Me represents a methyl group, and% is% by weight.
And parts are parts by weight. In addition, the viscosity shows a value at 25 ° C.

[Example 1] 80 parts of chloroplatinic acid, 1,3-
To a mixture of 160 parts of divinyl-1,1,3,3-tetramethyldisiloxane and 400 parts of ethanol was added 160 parts of sodium hydrogen carbonate. With stirring, mix this mixture with 7
The reaction was carried out at 0 to 80 ° C for 4 hours. Next, the generated salt was filtered, and then the volatile component was distilled off from the filtrate under reduced pressure at 50 ° C.
After re-precipitating the reprecipitated salt, it was diluted with toluene so that the amount of platinum was 0.5%, 1,3, divinyl-1,1,
A platinum complex (Platinum catalyst A) having 3,3-tetramethyldisiloxane as a ligand was obtained.

10 parts of this platinum catalyst C ₆ H ₅ Si (O
10 parts of SiHMe ₂ ) ₃ was added at room temperature of 25 ° C.,
The mixture was uniformly mixed and allowed to stand at room temperature for 2 hours to obtain a brown transparent platinum complex (platinum catalyst B).

Next, 100 parts of a dimethylpolysiloxane capped with vinyl dimethylsiloxy groups at both ends of the molecular chain (viscosity 60
0 cs) and 62 mol% Me ₂ SiO _2/2 units, 28
Mol% HMeSiO _2/2 units, 10 mol% HMe
8.3 parts of methyl hydrogen polysiloxane consisting of ₂ SiO _1/2 units were uniformly mixed at room temperature. Platinum catalyst B obtained above in this organopolysiloxane composition
When 2 parts were added at room temperature of 25 ° C and mixed uniformly, 7
Hardened in minutes.

[0044] [Example 2] _C 6 _{H 5} in the platinum catalyst A10 parts
0.3 part of Si (OSiHMe ₂ ) ₃ was added at room temperature of 25 ° C., uniformly mixed and allowed to stand at room temperature for 2 hours to obtain a dark brown transparent platinum complex (platinum catalyst C). Next, 1 part of this platinum catalyst C was added to an organopolysiloxane composition similar to that of Example 1 at room temperature of 25 ° C., and the mixture was uniformly mixed and cured in 6 minutes.

Example 3 Me ₃ S was added to 10 parts of platinum catalyst A.
13 parts of iOSiMe ₂ H was added at room temperature of 25 ° C.,
The mixture was uniformly mixed and allowed to stand at room temperature for 2 hours to obtain a yellow transparent platinum complex (platinum catalyst D). Next, 2.3 parts of this platinum catalyst D was added to the same organopolysiloxane composition as in Example 1 at room temperature of 25 ° C., and the mixture was uniformly mixed, whereupon it was cured in 17 minutes.

Example 4 Me ₃ S was added to 10 parts of platinum catalyst A.
0.4 part of iOSiMe ₂ H was added at room temperature of 25 ° C., uniformly mixed and allowed to stand at room temperature for 2 hours to obtain a dark brown transparent platinum complex (platinum catalyst E). Next, the platinum catalyst E1 was added to the same organopolysiloxane composition as in Example 1.
When the parts were added at room temperature of 25 ° C. and mixed uniformly, curing took place in 8 minutes.

[Comparative Example 1] Platinum catalyst A was added to the same organopolysiloxane composition as in Example 1 at room temperature of 25 ° C.
When added in parts, it was cured in 15 seconds.

The above results are summarized in Table 1.

[0049]

[Table 1] * SiH / Pt molar ratio: The molar ratio of the SiH group in the component (B) to the platinum atom in the component (A).

From Table 1, it can be seen that the catalyst composition of the present invention has a longer pot life and a better workability than the conventional catalyst because of its longer curing time at room temperature.

[Example 5] 100 parts of a dimethylpolysiloxane capped with vinyl dimethylsiloxy groups at both ends of a molecular chain (viscosity 600 cs), 62 mol% Me ₂ SiO _2/2 units, 28 mol% HMeSiO _2/2 units, 10 mol%
8.3 parts of methylhydrogenpolysiloxane consisting of HMe ₂ SiO _1/2 unit and 0.1 part of ethynylcyclohexanol as a reaction control agent were uniformly mixed at room temperature of 25 ° C. 0.6 part of platinum catalyst B was added to this organopolysiloxane composition and uniformly mixed at room temperature of 25 ° C. to obtain a composition 1.

Example 6 In the same formulation as in Example 5, 0.3 parts of platinum catalyst C was added instead of platinum catalyst B, and 2
Composition 2 was obtained by uniformly mixing at room temperature of 5 ° C.

Example 7 In the same formulation as in Example 5, 0.7 parts of platinum catalyst D was added instead of platinum catalyst B, and 2
Composition 3 was obtained by uniformly mixing at room temperature of 5 ° C.

[Example 8] In the same formulation as in Example 5, 0.3 parts of platinum catalyst E was added in place of platinum catalyst B, and 2
Composition 4 was obtained by uniformly mixing at room temperature of 5 ° C.

[Comparative Example 2] In the same formulation as in Example 5, 0.3 part of platinum catalyst A was added instead of platinum catalyst B, and 2
Composition 5 was obtained by uniformly mixing at room temperature of 5 ° C.

The curing exothermic peaks of these compositions 1 to 5 at 90 ° C. were measured by DSC (differential thermal analysis), and the time to the apex of the exothermic peaks is summarized in Table 2.

[0057]

[Table 2]

From Table 2, it can be seen that the catalyst composition of the present invention is superior in curability at high temperature as compared with the conventional catalyst.

Claims (3)

(57) [Claims] 1. A platinum complex having (A) an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand, and (B) one to three hydrogen atoms bonded to silicon atoms in one molecule. It is composed of an organohydrogensiloxane or an organohydrogensyl alkylene compound, and the number of silicon atom-bonded hydrogen atoms in the component (B) is 10 relative to 1 mol of platinum atom in the component (A).
A catalyst composition for addition reaction, which is mixed so as to have a mole or more. 2. The component (A) and the component (B) are 0-5.
The catalyst composition for addition reaction according to claim 1, which is obtained by contacting at a temperature of 0 ° C for 1 to 4 hours and uniformly mixing. 3. An organopolysiloxane composition comprising an organopolysiloxane containing at least two alkenyl groups in one molecule and an organohydrogenpolysiloxane containing at least two silicon-bonded hydrogen atoms in one molecule. (A) a platinum complex having an alkenyl group-containing organosilane or an alkenyl group-containing organosiloxane as a ligand, and (B) an organohydro compound containing 1 to 3 hydrogen atoms bonded to a silicon atom in one molecule. A siloxane or an organohydrogensyl alkylene compound, and 0 to 50 such that the silicon atom-bonded hydrogen atom in the component (B) is 10 mol or more per 1 mol of the platinum atom in the component (A). 1-4 at a temperature of ℃
A curable organopolysiloxane composition comprising a catalyst composition for addition reaction obtained by contacting for a period of time and uniformly mixing.