Curable fluorosilicone composition

Abstract

The curable fluorosilicone composition of the present invention comprises at least: (A) an organopolysiloxane having at least two alkenyl groups and at least one fluoroalkyl group in one molecule; (B) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms and at least one fluoroalkyl group in one molecule; (C) a catalyst for platinum group metal-based hydrosilylation reaction; and (D) a hydrosilylation reaction inhibitor having an aliphatic unsaturated bond, the (C) component being a capsule-type catalyst with an acrylic resin as a wall material, the platinum group metal in the (C) component being 0.1 to 100 ppm in mass units relative to the present composition, and the molar ratio of the aliphatic unsaturated bond in the (D) component to the platinum group metal in the (C) component being 1 to 100. The present composition has good curability and a sufficient pot life at ordinary temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to a curable fluorinated silicone composition. BACKGROUND

[0002] A curable fluorinated silicone composition which cures by an addition reaction in the presence of a catalyst for a platinum group metal-based hydrosilylation reaction forms a silicone cured product which is excellent in cold resistance and solvent resistance, and is thus also used as a sealing material for electrical / electronic parts (see Patent Documents 1 and 2). Such a curable fluorinated silicone composition has a problem that the curing speed is slow, and if a sufficient curing speed is desired, the pot life at room temperature is significantly shortened.

[0003] Therefore, in Patent Document 3, a method of controlling the curing initiation time and the curing time of a curable fluorinated silicone composition by compounding a crosslinking agent mixture containing an alkylhydrogensiloxane containing a fluorine-containing alkyl group is proposed.

[0004] On the other hand, in Patent Documents 4 and 5, a method of improving the storage stability and the curability of a curable silicone composition by encapsulating a catalyst for a platinum group metal-based hydrosilylation reaction as a wall material is disclosed. However, in a curable fluorinated silicone composition, it has not been known that an encapsulated catalyst having an acrylic resin as a wall material improves the pot life of the composition at room temperature.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT DOCUMENTS

[0007] Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 05-070693

[0008] Patent Document 2: Japanese Patent Application Laid-Open (JP-A) No. 07-070444

[0009] Patent Document 3: Japanese Patent Application Laid-Open (JP-A) No. 10-081825

[0010] Patent Document 4: Japanese Patent Application Laid-Open (JP-A) No. 64-045468

[0011] Patent Document 5: Japanese Patent Application Laid-Open (JP-A) No. 02-117960 SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] An object of the present application is to provide a curable fluorinated silicone composition which is excellent in curability and has a sufficient pot life at room temperature.

[0014] SOLUTION TO PROBLEM

[0015] The curable fluorosilicone composition of the present application is characterized by comprising at least:

[0016] (A) 100 parts by mass of an organopolysiloxane having at least two alkenyl groups and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule;

[0017] (B) an organopolysiloxane having at least two silicon-bonded hydrogen atoms and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule: the silicon-bonded hydrogen atoms in this component are in an amount of 0.1 to 10 moles per 1 mole of the total of the aliphatic unsaturated bonds in the present composition;

[0018] (C) a catalyst for platinum group metal-based hydrosilylation reaction; and

[0019] (D) a hydrosilylation reaction inhibitor having an aliphatic unsaturated bond,

[0020] The (C) component is a capsule type catalyst with an acrylic resin as a wall material, the platinum group metal in the (C) component is in an amount of 0.1 to 100 ppm in mass units per the present composition, and the molar ratio of the aliphatic unsaturated bond in the (D) component to the platinum group metal in the (C) component is 1 to 100.

[0021] In the above composition, it is preferable that the (A) component comprises a branched organopolysiloxane having alkenyl groups bonded only to silicon atoms at the molecular chain terminals.

[0022] Further, in the above composition, it is preferable that the (B) component comprises an organopolysiloxane having hydrogen atoms bonded only to silicon atoms at the molecular chain terminals, and it is particularly preferable that the (B) component is a mixture of a linear organopolysiloxane having hydrogen atoms bonded only to silicon atoms at both molecular chain terminals and a branched organopolysiloxane having hydrogen atoms bonded only to silicon atoms at the molecular chain terminals.

[0023] Further, in the above composition, it is preferable that the (D) component is a silylated acetylene compound, and it is particularly preferable that the (D) component is a compound of the general formula:

[0024] [Chemical Formula 1]

[0025]

[0026] (In the formula, R 1 are the same or different, and are a hydrogen atom or a monovalent hydrocarbon group, R 2 is a linking group or an alkylene group, R 3 is an alkyl group, an alkenyl group, or an aryl group, a is an integer of 1 to 4, and b is an integer of 0 to 5.)

[0027] the silylated acetylene compound represented by the formula:

[0028] [Chemical Formula 2]

[0029]

[0030] (In the formula, R 1 , R 3 , a, and b are the same as described above, and c is an integer of 4 to 6.)

[0031] silanized acetylene compound represented by the formula (1), or a mixture thereof.

[0032] Effects of the Invention

[0033] The curable fluoroorganosilicon composition of the present application is characterized by being excellent in curability and having a sufficient pot life at ordinary temperature. DETAILED DESCRIPTION

[0034] Definitions of Terms

[0035] In the present specification, the "capsule type catalyst" means a resin particle in which a thermoplastic acrylic resin is used as a wall material, and the inside of the resin particle contains or disperses a platinum group metal-based catalyst for a hydrosilylation reaction, and the hydrosilylation reaction is not promoted or is hardly promoted, and the hydrosilylation reaction is remarkably promoted by heating to a temperature above the glass point thereof.

[0036] Further, in the present specification, the "aliphatic unsaturated bond" means the total of aliphatic carbon-carbon double bonds and aliphatic carbon-carbon triple bonds.

[0037] Further, in the present specification, the "silanized acetylene compound" means an acetylene compound having a silyl group, for example, a reaction product in which a hydroxyl group in an acetylenic alcohol is substituted with a siloxy group, which is disclosed in the specification of U.S. Patent No. 5449802 and the specification of U.S. Patent No. 5708046.

[0038] Curable fluoroorganosilicon composition

[0039] (A) component is an organic polysiloxane having at least two alkenyl groups and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule. As the alkenyl group in the (A) component, for example, a carbon atom number of 2 to 12 alkenyl group such as a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, and the like, preferably a vinyl group, a hexenyl group can be exemplified. Further, as the fluoroalkyl group in the (A) component, for example, a 3,3,3-trifluoropropyl group, a 4,4,4,3,3-pentafluorobutyl group, a 5,5,5,4,4,3,3-heptafluoropentyl group, a 6,6,6,5,5,4,4,3,3-nonafluorohexyl group, a 7,7,7,6,6,5,5,4,4,3,3-undecafluoroheptyl group, preferably a 3,3,3-trifluoropropyl group can be exemplified. Furthermore, as the group other than the alkenyl group and the fluoroalkyl group bonded to the silicon atom in the (A) component, for example, a carbon atom number of 1 to 12 alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group; a carbon atom number of 6 to 12 aryl group such as a phenyl group, a tolyl group, a xylyl group; an aralkyl group of a carbon atom number of 7 to 12 such as a benzyl group, a phenethyl group, preferably a methyl group, a phenyl group can be exemplified. Further, within a range not impairing the object of the present application, a small amount of a hydroxyl group, or an alkoxy group such as a methoxy group, an ethoxy group can be bonded to the silicon atom in the (A) component.

[0040] The molecular structure of the (A) component is not limited, and for example, a straight chain, a branched chain, a straight chain having a part of a branched chain, a resin shape, preferably a straight chain, a branched chain can be exemplified. Further, the viscosity of the (A) component at 25°C is not limited, and is preferably in a range of 100 to 100000 mPa-s or in a range of 500 to 50000 mPa-s. The reason is that, if the viscosity of the (A) component is equal to or more than the lower limit of the above range, the mechanical strength of the obtained fluorinated silicone cured product is improved, and on the other hand, if the viscosity of the (A) component is equal to or less than the upper limit of the above range, the handling workability, the filling property of the present composition are improved. Note that the viscosity of the (A) component can be measured by a rotational viscometer, a rotational rheometer according to "Plastics - Resins in liquid, cream or dispersion form - Determination of viscosity at fixed shear rate by rotational viscometer" of JIS K7117-2: 1999.

[0041] As such (A) component, for example, dimethylvinylsiloxy-terminated dimethylsiloxane / methyl (3,3,3-trifluoropropyl)siloxane copolymer, dimethylvinylsiloxy-terminated dimethylsiloxane / methylvinylsiloxane / methyl (3,3,3-trifluoropropyl)siloxane copolymer, dimethylvinylsiloxy-terminated dimethylsiloxane / methylphenylsiloxane / methyl (3,3,3-trifluoropropyl)siloxane copolymer, trimethylsiloxy-terminated methyl (3,3,3-trifluoropropyl)siloxane / methylvinylsiloxane copolymer, and a mixture of two or more of them, preferably a branched organopolysiloxane having only a silicon atom-bonded alkenyl group at the molecular chain terminal.

[0042] The (B) component is a crosslinking agent of the present composition, and is an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule. As the fluoroalkyl group in the (B) component, 3,3,3-trifluoropropyl group, 4,4,4,3,3-pentafluorobutyl group, 5,5,5,4,4,3,3-heptafluoropentyl group, 6,6,6,5,5,4,4,3,3-nonafluorohexyl group, 7,7,7,6,6,5,5,4,4,3,3-undecafluoroheptyl group, and the like can be exemplified, and preferably a 3,3,3-trifluoropropyl group. Further, as the group other than the hydrogen atom and the fluoroalkyl group bonded to the silicon atom in the (B) component, an alkyl group having 1 to 12 carbon atoms such as a methyl group, an ethyl group, a propyl group, and the like; an aryl group having 6 to 12 carbon atoms such as a phenyl group, a tolyl group, a xylyl group, and the like can be exemplified, and preferably a methyl group or a phenyl group.

[0043] The molecular structure of the (B) component is not limited, and for example, a straight chain, a branched chain, a straight chain having a part of a branched chain, a ring, a resin, and the like can be exemplified. Further, the viscosity of the (B) component is not limited, and preferably, the kinematic viscosity at 25°C is in the range of 1 to 10,000 mm 2 / s or 1 to 2,000 mm 2 / s. The reason for this is that if the viscosity of the (B) component is equal to or higher than the lower limit of the above range, the mechanical strength of the obtained fluorinated silicone cured product is improved, and on the other hand, if the viscosity of the (B) component is equal to or lower than the upper limit of the above range, the handling workability and the filling property of the present composition are improved. Note that the viscosity of the (B) component can be measured by a viscometer according to JIS K2283:2000 "Petroleum and Petroleum Products - Test Method for Kinematic Viscosity and Calculation of Viscosity Index".

[0044] As the (B) component, for example, mention can be made of: a methylhydrogensiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer terminated at both molecular chain terminals by trimethylsiloxy groups, a dimethylsiloxane / methylhydrogensiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer terminated at both molecular chain terminals by dimethylhydrogensiloxy groups, a methyl(3,3,3-trifluoropropyl)siloxane terminated at both molecular chain terminals by dimethylhydrogensiloxy groups, a dimethylsiloxane / methylhydrogensiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer terminated at both molecular chain terminals by dimethylhydrogensiloxy groups, and a mixture of two or more of these, preferably an organopolysiloxane having only silicon-bonded hydrogen atoms at the molecular chain terminals, particularly preferably a mixture of a linear organopolysiloxane having only silicon-bonded hydrogen atoms at both molecular chain terminals and a branched organopolysiloxane having only silicon-bonded hydrogen atoms at the molecular chain terminals.

[0045] The content of the (B) component is 0.1 to 10 moles of silicon-bonded hydrogen atoms in the component per 1 mole of the total of the aliphatic unsaturated bonds in the present composition, preferably 0.1 to 5 moles, 0.5 to 5 moles, or 0.5 to 3 moles. The reason for this is that if the content of the (B) component is in an amount of 0.1 moles or more of the lower limit of the above range, the present composition sufficiently cures, whereas if the content of the (B) component is in an amount of 10 moles or less of the upper limit of the above range, the heat resistance of the resulting fluorinated silicone cured product is improved.

[0046] The (C) component is a catalyst for promoting the curing of the present composition, and is a catalyst for a platinum group metal-based hydrosilylation reaction in a capsule type with an acrylic resin as the wall material. As the platinum group metal-based catalyst in the (C) component, mention can be made of: a platinum-based catalyst, a rhodium-based catalyst, a ruthenium-based catalyst, an iridium-based catalyst, a palladium-based catalyst, preferably a platinum-based catalyst. As the platinum-based catalyst, mention can be made of: chloroplatinic acid, chloroplatinic acid hexahydrate, platinum dichloride, an alcohol solution of chloroplatinic acid, an olefin complex of chloroplatinic acid, a chloroplatinic acid / alkenylsiloxane complex, a diketone complex of platinum, an alkenylsiloxane complex of platinum, an olefin complex of platinum, preferably a platinum / alkenylsiloxane complex, particularly a 1,3-diethynyl-1,1,3,3-tetramethyldisiloxane complex of platinum.

[0047] The acrylic resin as the wall material of the (C) component is not limited, and for example, polymethacrylate resin, polyacrylate resin, polyacrylamide resin, acrylic / styrene copolymer resin, preferably polymethacrylate resin, methyl methacrylate / butyl methacrylate copolymer resin, and the like can be exemplified. Such (C) component preferably has a glass transition point in the range of 50 to 100°C. Note that the glass transition temperature can be obtained according to the method described in JIS K 7121-1987 "Plastic Transition Temperature Measurement Method".

[0048] The method for producing the (C) component is not limited, and for example, a method in which a platinum group metal-based hydrosilylation reaction is carried out using a catalyst dispersed in a solution of an acrylic resin, a method in which a platinum group metal-based hydrosilylation reaction is carried out using a catalyst dispersed in water to produce a capsule type catalyst, a method in which a platinum group metal-based hydrosilylation reaction is carried out using a catalyst dispersed in an acrylic monomer, and the acrylic monomer is polymerized while being emulsified in water to produce a capsule type catalyst, as described in Japanese Patent Application Laid-Open No. 64-045468, Japanese Patent Application Laid-Open No. 64-047442, Japanese Patent Application Laid-Open No. 02-009440, and Japanese Patent Application Laid-Open No. 02-117960, can be exemplified.

[0049] The (D) component is a hydrosilylation reaction inhibitor having an aliphatic unsaturated bond, which is used to improve the storage stability of the present composition, or to adjust the curability of the present composition. As such (D) component, acetylenic alcohols such as 1-ethynylcyclohexane-1-ol, 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-phenyl-3-butyn-2-ol, and the like; enyne compounds such as 3-methyl-3-penten-1-yne, 3,5-dimethyl-3-hexen-1-yne, and the like; and silylated acetylenic compounds in which the hydroxyl group of the acetylenic alcohol is substituted with a siloxy group, preferably silylated acetylenic compounds, can be exemplified.

[0050] The silylated acetylenic compounds of such (D) component are disclosed in, for example, U.S. Patent No. 5449802, U.S. Patent No. 5708046, and can be exemplified by the general formula:

[0051] [Chemical Formula 3]

[0052]

[0053] silylated acetylenic compounds, the general formula:

[0054] [Chemical Formula 4]

[0055]

[0056] silylated acetylenic compounds, or a mixture thereof.

[0057] In the formula, R 1 They may be the same or different, consisting of a hydrogen atom or a monovalent hydrocarbon group. As R... 1 Examples of monovalent hydrocarbon groups include: alkyl groups with 1 to 12 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; aryl groups with 6 to 12 carbon atoms such as phenyl, tolyl, and xylyl; and aralkyl groups with 7 to 12 carbon atoms such as benzyl and phenethyl, with methyl being preferred.

[0058] Furthermore, in the formula, R 2 It is a linking group or an alkylene group. As R 2 Examples of alkylene groups include methylene, ethylene, propylene, butylene, pentylene, hexylene, and heptylene, which have 1 to 12 carbon atoms. 2 Preferably, it is a linking group.

[0059] Furthermore, in the formula, R 3 It is alkyl, alkenyl, or aryl. As R 3 Alkyl groups, for example, include alkyl groups with 1 to 12 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl. As R 3 Examples of alkenyl groups include vinyl, allyl, butenyl, pentenyl, hexenyl, and heptenyl alkenyl groups with 2 to 12 carbon atoms. As R 3 Examples of aryl groups include phenyl, tolyl, xylyl, and other aryl groups with 6 to 12 carbon atoms.

[0060] In the formula, a is an integer from 1 to 4, preferably 3 or 4.

[0061] Furthermore, in the formula, b is an integer from 0 to 5, preferably 0.

[0062] Furthermore, in the formula, c is an integer from 4 to 6, preferably 5.

[0063] Examples of silanized acetylene compounds that are such (D) components include the following compounds.

[0064] [Chemical Formula 5]

[0065]

[0066] [Chemical Formula 6]

[0067]

[0068] [Chemical Formula 7]

[0069]

[0070] [Chemical Formula 8]

[0071]

[0072] [Chemical Formula 9]

[0073]

[0074] [Chemical Formula 10]

[0075]

[0076] (D) The preparation method of the silanized acetylene compound is well known, for example, by means of the general formula disclosed in U.S. Patent No. 5,449,802 and U.S. Patent No. 5,708,046:

[0077] [Chemical Formula 11]

[0078]

[0079] The alkynols and / or general formulas shown are:

[0080] [Chemical Formula 12]

[0081]

[0082] The alkynols shown are of the general formula:

[0083] X d SiR 3 (4-d)

[0084] The chlorosilane shown is prepared by a condensation reaction. It should be noted that in the above formula, R... 1 R 2 R 3 b and c are the same as described above. Furthermore, in the above formula, X is a hydrolyzable group, which can be exemplified by: alkoxy groups such as methoxy, ethoxy, and propoxy; halogen atoms such as chlorine atoms; or acetoxy groups. Furthermore, in the above formula, d is an integer from 1 to 4, preferably 2 or 3.

[0085] In the present composition, with respect to the content of the (C) component and the (D) component, the molar ratio of the aliphatic unsaturated bond in the (D) component to the platinum group metal in the (C) component is 1 to 100 with respect to 0.1 to 100 ppm of the platinum group metal in the (C) component in terms of mass in the present composition, and preferably, the molar ratio of the aliphatic unsaturated bond in the (D) component to the platinum group metal in the (C) component is 1 to 50 with respect to 0.1 to 50 ppm of the platinum group metal in the (C) component in terms of mass. The reason for this is that if the content of the (C) component is above the lower limit of the above range, the curing of the present composition proceeds sufficiently, whereas if the content of the (C) component is below the upper limit of the above range, the resulting fluorinated silicone cured product becomes difficult to color. Further, if the content of the (D) component is above the lower limit of the above range, the pot life of the present composition at room temperature becomes sufficient, whereas if the content of the (D) component is below the upper limit of the above range, the curability of the present composition is good.

[0086] In the present composition, an adhesion-improving agent can also be contained as another arbitrary component for the purpose of improving the adhesion of the resulting fluorinated silicone cured product. As such an adhesion-improving agent, a silicone compound having at least one silicon-bonded alkoxy group in one molecule is preferred. As the alkoxy group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a methoxyethoxy group, and particularly a methoxy group can be exemplified. Further, as a group other than the silicon-bonded alkoxy group of the silicone compound, monovalent hydrocarbon groups substituted or unsubstituted with an alkyl group, an alkenyl group, an aryl group, an aralkyl group, a halogenated alkyl group, and the like; an epoxypropyloxyalkyl group such as a 3-epoxypropyloxypropyl group and a 4-epoxypropyloxybutyl group; an epoxy cyclohexylalkyl group such as a 2-(3,4-epoxycyclohexyl)ethyl group and a 3-(3,4-epoxycyclohexyl)propyl group; a monovalent organic group containing an epoxy group such as a 4-oxiranylbutyl group and an 8-oxiranyloctyl group; a monovalent organic group containing an acryl group such as a 3-methacryloxypropyl group; and a hydrogen atom can be exemplified. The silicone compound preferably has a silicon-bonded alkenyl group or a silicon-bonded hydrogen atom. Further, from the viewpoint of imparting good adhesion to various substrates, the silicone compound preferably has at least one monovalent organic group containing an epoxy group in one molecule. As such a silicone compound, a silane compound, a siloxane oligomer, and an alkyl silicate can be exemplified. As the molecular structure of the silane compound, the siloxane oligomer, or the alkyl silicate, a linear structure, a linear structure having a part of a branched chain, a branched chain structure, a cyclic structure, a network structure, and particularly a linear structure, a branched chain structure, and a network structure can be exemplified. As such a silicone compound, a silane compound such as a 3-epoxypropyloxypropyltrimethoxysilane, a 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and a 3-methacryloxypropyltrimethoxysilane; a mixture of a siloxane compound having at least one silicon-bonded alkenyl group or a silicon-bonded hydrogen atom and a silicon-bonded alkoxy group in one molecule, a silane compound having at least one silicon-bonded alkoxy group, or a siloxane compound and a siloxane compound having at least one silicon-bonded hydroxyl group and a silicon-bonded alkenyl group in one molecule; a polymethyl silicate; a polyethyl silicate; and an epoxy group-containing polyethyl silicate can be exemplified. The content of such an adhesion-improving agent is not particularly limited, and is preferably at most 5% by mass relative to the present composition.

[0087] In the present composition, a metal compound such as copper acetylacetonate and copper phthalocyanine can also be added as another arbitrary component for the purpose of improving the heat resistance, cold resistance, or weather resistance of the resulting fluorinated silicone cured product. The content of such a metal compound is not limited, and is preferably at most 100 ppm or at most 50 ppm by mass relative to the present composition.

[0088] In the present composition, an organopolysiloxane having no alkenyl group and hydrogen atom on a silicon atom in the molecule and a fluoroalkyl group having 3 to 12 carbon atoms can also be contained. As such an organopolysiloxane, for example, a dimethylsiloxane / methyl (3, 3, 3-trifluoropropyl) siloxane copolymer capped at both molecular chain terminals with trimethylsilyl oxide, a methyl (3, 3, 3-trifluoropropyl) polysiloxane capped at both molecular chain terminals with trimethylsilyl oxide, and a mixture of two or more of these can be exemplified. Further, the viscosity of such an organopolysiloxane at 25°C is not limited, and is preferably in the range of 100 to 100,000 mPa-s or in the range of 500 to 50,000 mPa-s. The content of such an organopolysiloxane is not limited, and is preferably at most 5 mass% relative to the present composition.

[0089] Further, in the present composition, a filler can also be contained without impairing the object of the present application. As such a filler, for example, reinforcing fillers such as fumed silica, fused silica, and precipitated silica; extending fillers such as quartz powder, diatomaceous earth, calcium carbonate, and magnesium carbonate; heat-resistant additives such as cerium oxide, cerium hydroxide, and iron oxide; pigments such as iron red, titanium oxide, and carbon black; and flame retardants can be exemplified.

[0090] Examples

[0091] The curable fluoroorganosilicon composition of the present application is described in detail by way of examples. Note that the values of viscosity in the examples are values at 25°C. Further, the pot life at 25°C of the curable fluoroorganosilicon composition and the curability thereof were measured as described below.

[0092] <Ratio of viscosity after prescribed number of days to initial viscosity>

[0093] The initial viscosity (mPa-s) at 25°C immediately after preparation, the viscosity (mPa-s) after 7 days and 21 days of standing at 25°C of the curable fluoroorganosilicon composition were measured by a rotational rheometer (viscoelasticity measuring device MCR102 or 302 manufactured by Anton-Paar) in accordance with the method prescribed in JIS K7117-2: 1999. Note that this measurement used a cone-plate with a diameter of 20 mm and an angle of 2°, and the shear rate was set to 10.0 (S -1 ). The ratio of the viscosity after the prescribed number of days to the initial viscosity was calculated.

[0094] <Curability of curable fluoroorganosilicon composition>

[0095] A cured product having a thickness of about 1.5 mm and a diameter of 15 mm was produced by heating the curable fluoroorganosilicon composition at 150°C for 1 hour. The shear modulus G' (Pa) at 23°C of the cured product was measured using a viscoelasticity measuring device (manufactured by Anton-Paar, Model MCR302). Note that the measurement was performed at an angular velocity of 6.28 x 10 -2 rad / s, and the value at 1.25 x 10 1 rad / s was calculated. -1

[0096] <Example 1-2, Comparative Examples 1-4>

[0097] A curable fluoroorganosilicon composition was produced by uniformly mixing the following ingredients so as to have the composition shown in Table 1. Note that the molar ratio of the total of 1 mole of silicon atom-bonded hydrogen atoms and aliphatic unsaturated bonds in the (B) ingredient in the present composition was set to 0.7.

[0098] The following ingredients were used as the (A) ingredient.

[0099] (a-1): a branched dimethylsiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer (content of vinyl group = about 1.03 mass%) in which at least two of the molecular chain terminals are capped with dimethylvinylsiloxy groups and the other molecular chain terminals are capped with trimethylsiloxy groups, having a viscosity of 820 mPa-s.

[0100] The following ingredients were used as the (B) ingredient.

[0101] (b-1): a dimethylsiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer (content of silicon atom-bonded hydrogen atoms = about 0.024 mass%) in which both of the molecular chain terminals are capped with dimethylhydrogensiloxy groups, having a kinematic viscosity of 710 mm 2 / s.

[0102] (b-2): a branched organopolysiloxane (content of silicon atom-bonded hydrogen atoms = about 0.59 mass%) represented by the formula:

[0103] CF3C2H4Si[OSi(CH3)2H]3

[0104] having a kinematic viscosity of 7 mm 2 / s.

[0105] The following ingredients were used as the (C) ingredient.

[0106] ​(c-1) : a methyl (3, 3, 3-trifluoropropyl) polysiloxane dispersion solution having a viscosity of 1300 mPa-s and both terminals of the molecular chain capped with trimethylsiloxy groups containing 10 mass% of a capsule type catalyst which is a 1, 3-divinyltetramethyldisiloxane solution of a 1, 3-divinyltetramethyldisiloxane complex of platinum microencapsulated with an acrylic resin (content of platinum metal = about 0.04 mass%), the glass transition temperature of the capsule type catalyst being 54.8°C.

[0107] (c-2) : a methyl (3, 3, 3-trifluoropropyl) polysiloxane dispersion solution having a viscosity of 1300 mPa-s and both terminals of the molecular chain capped with trimethylsiloxy groups containing 10 mass% of a capsule type catalyst which is a 1, 3-divinyltetramethyldisiloxane solution of a 1, 3-divinyltetramethyldisiloxane complex of platinum microencapsulated with a silicone resin (content of platinum metal = about 0.04 mass%), the glass transition temperature of the capsule type catalyst being 60.5°C.

[0108] (c-3) : a methyl (3, 3, 3-trifluoropropyl) polysiloxane dispersion solution having a viscosity of 1300 mPa-s and both terminals of the molecular chain capped with trimethylsiloxy groups containing 10 mass% of a capsule type catalyst which is a 1, 3-divinyltetramethyldisiloxane solution of a 1, 3-divinyltetramethyldisiloxane complex of platinum microencapsulated with a polycarbonate resin (content of platinum metal = about 0.04 mass%), the glass transition temperature of the capsule type catalyst being 135.1°C.

[0109] The following ingredients were used as the (D) ingredient.

[0110] (d-1) : 7.88 mass% of a compound of the formula:

[0111] [Chemical Formula 13]

[0112]

[0113] A methyl (3, 3, 3-trifluoropropyl) polysiloxane solution having a viscosity of 1300 mPa-s and both terminals of the molecular chain capped with trimethylsiloxy groups of a silylated acetylene compound shown below.

[0114] (d-2) : 1-ethynyl-cyclohexane-1-ol.

[0115] Further, the following ingredients were used as the (E) ingredient.

[0116] (e-1) : a tackifier formed from a reaction product of a dimethylsiloxane / methylvinylsiloxane copolymer oligomer (content of vinyl group = 10.9 mass%) having a viscosity of 20 mPa-s, in which both terminal groups of the molecular chain are silanol groups, and 3-glycidoxypropyltrimethoxysilane at a molar ratio of 1 : 2.2.

[0117] In addition, the following ingredients were used as the (F) component.

[0118] (f-1) : a methyl (3, 3, 3-trifluoropropyl) polysiloxane dispersion liquid having a viscosity of 1300 mPa-s, in which both terminal groups of the molecular chain are trimethylsiloxy groups, and 3.75 mass% of copper acetylacetonate.

[0119] (f-2) : a methyl (3, 3, 3-trifluoropropyl) polysiloxane dispersion liquid having a viscosity of 1300 mPa-s, in which both terminal groups of the molecular chain are trimethylsiloxy groups, and 35 mass% of carbon black.

[0120] [Table 1]

[0121]

[0122] Industrial applicability

[0123] The curable fluoroorganosilicon composition of the present application has good curability and has a sufficient pot life at ordinary temperature, and is therefore preferably used, for example, as a protective sealing material, an impact absorbing material, etc. for electrical and electronic parts such as ICs.

Claims

1. A curable fluorinated organosilicon composition, comprising at least: (A) 100 parts by mass of an organopolysiloxane having at least two alkenyl groups and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule; (B) An organopolysiloxane having at least two silicon atoms bonded to hydrogen atoms and at least one fluoroalkyl group having 3 to 12 carbon atoms in one molecule: the amount of silicon atoms bonded to hydrogen atoms in this component is 0.1 to 10 moles relative to the total amount of 1 mole of aliphatic unsaturated bonds in the composition; (C) Platinum group metal catalysts for hydrosilylation reactions; and (D) Inhibitors of hydrosilylation reactions with aliphatic unsaturated bonds. The (C) component is a capsule-type catalyst with acrylic resin as the wall material, and the amount of platinum group metals in the (C) component relative to the composition is 0.1 to 100 ppm by mass. The molar ratio of aliphatic unsaturated bonds in the (D) component to platinum group metals in the (C) component is 1 to 100.

2. The curable fluorinated organosilicon composition according to claim 1, wherein, (A) The ingredients include: branched organopolysiloxanes with alkenyl groups at the ends of the molecular chains that are bonded only to silicon atoms.

3. The curable fluorinated organosilicon composition according to claim 1, wherein, (B) The ingredients include: organopolysiloxanes with hydrogen atoms at the ends of the molecular chains that are bonded only to silicon atoms.

4. The curable fluorinated organosilicon composition according to claim 1, wherein, (B) is a mixture of linear organopolysiloxanes with hydrogen atoms bonded only to silicon atoms at both ends of the molecular chain and branched organopolysiloxanes with hydrogen atoms bonded only to silicon atoms at the ends of the molecular chain.

5. The curable fluorinated organosilicon composition according to claim 1, wherein, (D) is a silanized acetylene compound.

6. The curable fluorinated organosilicon composition according to claim 1, wherein, (D) The components are silanized acetylene compounds represented by the following general formula (chemical formula 14), silanized acetylene compounds represented by the following general formula (chemical formula 15), or mixtures thereof. [Chemical Formula 14] In the formula, R 1 Whether they are the same or different, they are either hydrogen atoms or monovalent hydrocarbon groups, R 2 R is a linking group. 3 It can be alkyl, alkenyl, or aryl, where a is an integer from 1 to 4, and b is an integer from 0 to 5. [Chemical Formula 15] In the formula, R 1 R 3 a and b are the same as described above, and c is an integer from 4 to 6.

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