Liquid addition-curable fluorosilicone composition, fluorosilicone rubber, and molded article

Abstract

A first aspect of the present invention provides an addition-curable fluorosilicone composition characterized by containing: (A) a vinyl group-containing organopolysiloxane represented by general formula (1) and having a viscosity of 100-500,000 mPa * s at 25 DEG C; (B) a branched organohydrogenpolysiloxane represented by formula (3) and having three or more silicon-atom-bonded hydrogen atoms in each molecule, said branched organohydrogenpolysiloxane being such that the number of silicon-atom-bonded hydrogen atoms in the component (B) is 0.5-10 per silicon-atom-bonded vinyl group in the composition; (C) an addition reaction catalyst in a catalytic amount; and (D) 10-60 parts by mass of a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by general formula (2) per 100 parts by mass of component (A), and the composition is liquid at 23 DEG C. As a result, it is possible to provide a liquid addition-curable fluorosilicone composition which has good curability, can maintain mechanical strength, and is suitable for injection molding and the like. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a liquid addition-curing fluorosilicone composition, a fluorosilicone rubber obtained by heating and curing the composition, and a molded product thereof. Background Art

[0002] For a long time, the cured products of addition-cured fluorosilicone rubber compositions have excellent gasoline resistance and oil resistance, and therefore have been used in aircraft and vehicle-mounted rubber parts, printer parts, etc. (Patent Document 1). In addition, in recent years, the cured products of addition-cured fluorosilicone rubber compositions have been studied for use in moving parts based on their sebum resistance, and for use in sealing parts for fuel cell vehicles based on their acid resistance. For the cured products of addition-cured fluorosilicone rubber compositions used for these parts, low compression set and maintained practical strength, i.e., mechanical strength, are sought. In particular, it is desired to develop a liquid addition-cured fluorosilicone rubber composition with excellent productivity. As processing methods with excellent productivity, casting molding, compression molding, and injection molding using molds are good, but the liquid addition-cured fluorosilicone rubber composition still has the problem of being unusable if it does not have a viscosity that can be applied to the above-mentioned processing methods.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-047290 Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] The first aspect of the present invention is made in view of the above circumstances, and aims to provide a liquid addition-curable fluorosilicone composition which has good curability and can maintain mechanical strength and is suitable for injection molding, etc. In addition, the purpose is also to provide a fluorosilicone rubber obtained by heating and curing the composition and a molded product thereof.

[0008] In addition, the second embodiment of the present invention is completed in view of the above situation, and the purpose is to provide a liquid addition-curable fluorosilicone composition, which has very good curability and excellent storage stability, and can form a fluorosilicone rubber that can maintain mechanical strength and is suitable for processing with excellent productivity. In addition, the purpose is also to provide a fluorosilicone rubber obtained by curing the composition.

[0009] (II) Technical solution

[0010] In order to solve the above technical problems, the first embodiment of the present invention provides an addition-curable fluorosilicone composition, characterized in that it contains:

[0011] (A) a vinyl-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1),

[0012] [Chemical formula 1]

[0013]

[0014] In the general formula (1), R 1 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800;

[0015] (B) a branched organohydrogenpolysiloxane represented by the following formula (3) having three or more silicon-bonded hydrogen atoms in one molecule, wherein the number of hydrogen atoms bonded to silicon atoms in the component (B) is 0.5 to 10 per silicon-bonded vinyl group in the composition,

[0016] [Chemical formula 2]

[0017]

[0018] In the above formula (3), R 4 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1 is a number of 2≤x1≤4, x2 is an integer of 0≤x2≤20, x3 is an integer of 0≤x3≤20 and satisfies 0≤x2+x3≤20, y1 is an integer of 0≤y1≤30, z1 is an integer of 0≤z1≤10, y2 is an integer of 0≤y2≤30, z2 is an integer of 0≤z2≤10, and z1+z2>0;

[0019] (C) an addition reaction catalyst in a catalytic amount; and

[0020] (D) a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (2), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A);

[0021] [Chemical formula 3]

[0022]

[0023] In the above general formula (2), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, and R 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20,

[0024] The addition-curable fluorosilicone composition is in a liquid state at 23°C.

[0025] The addition-curable fluorosilicone composition according to the first aspect of the present invention has good curability and can maintain mechanical strength, and is suitable for injection molding and the like.

[0026] Furthermore, a first aspect of the present invention provides a fluorosilicone rubber characterized in that it is a cured product of the above-mentioned addition-curing fluorosilicone composition.

[0027] With the fluorosilicone rubber of the first aspect of the present invention, good mechanical strength can be maintained.

[0028] Furthermore, a first aspect of the present invention provides a fluorosilicone rubber molded product, characterized in that it is a molded body of the above-mentioned fluorosilicone rubber.

[0029] The fluorosilicone rubber molded product of the first embodiment of the present invention has excellent gasoline resistance and oil resistance, and can therefore be used in rubber parts for aircraft and vehicles, printer parts, etc. Based on its sebum resistance, it can also be used in moving parts, and based on its acid resistance, it can also be used in sealing parts for fuel cell vehicles.

[0030] In addition, in order to solve the above technical problems, the second embodiment of the present invention provides an addition-curable fluorosilicone composition, which is a liquid addition-curable fluorosilicone composition, characterized in that it contains:

[0031] (A') an alkenyl group-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1A),

[0032] [Chemical formula 4]

[0033]

[0034] In the general formula (1A), R 1are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800;

[0035] (B') an organohydrogenpolysiloxane having 3 to 5 silicon-bonded hydrogen atoms in one molecule represented by the following general formula (2A), wherein the number of hydrogen atoms bonded to silicon atoms in the component (B') is 0.5 to 10 per silicon-bonded alkenyl group in the composition,

[0036] [Chemical formula 5]

[0037]

[0038] In the above general formula (2A), R 4 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf' is independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1' is an integer of 3≤x1'≤5, x2' and x3' are integers of 0≤x2'+x3'≤20, y1' is an integer of 0≤y1'≤30, y2' is an integer of 0≤y2'≤30, z1' is an integer of 0≤z1'≤10, z2' is an integer of 0≤z2'≤10, w is 0<w≤10, and x2', x3', y1', y2', z1' and z2' are not 0 at the same time;

[0039] (C') an addition reaction catalyst in a catalytic amount; and

[0040] (D') a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (3A), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A');

[0041] [Chemical formula 6]

[0042]

[0043] In the above general formula (3A), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, R 2 Independently of each other, the above R 3or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20,

[0044] The addition-curable fluorosilicone composition is in a liquid state at 23°C.

[0045] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention cures rapidly even at relatively low temperatures, and therefore has very good curability, excellent storage stability, and can form a fluorosilicone rubber that can maintain mechanical strength by curing. The liquid addition-curable fluorosilicone composition is suitable as a material for processes with excellent productivity such as casting molding, compression molding, and injection molding, and can therefore contribute to improving the productivity of molded products.

[0046] Furthermore, a second aspect of the present invention provides a fluorosilicone rubber characterized in that it is a cured product of the addition-curing fluorosilicone composition of the second aspect of the present invention.

[0047] The fluorosilicone rubber according to the second aspect of the present invention can exhibit low compression set and high mechanical strength.

[0048] (III) Beneficial effects

[0049] The addition-curable fluorosilicone composition of the first embodiment of the present invention is in liquid form, and can be cured quickly even at a relatively low temperature, thus having good curability, and forming a fluorosilicone rubber that can maintain mechanical strength. In addition, the liquid addition-curable fluorosilicone composition is suitable as a material for casting molding, compression molding, and injection molding, and can therefore contribute to improving the productivity of molded products.

[0050] In addition, as described above, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention will cure rapidly even at a relatively low temperature, so the curing property is very good, and the storage stability is also excellent, and a fluorosilicone rubber that can maintain mechanical strength can be formed. In addition, the liquid addition-curable fluorosilicone composition is suitable as a material for processing with excellent productivity such as casting molding, compression molding and injection molding, so it can contribute to the improvement of the productivity of molded products.

[0051] Furthermore, the fluorosilicone rubber according to the second aspect of the present invention can exhibit low compression set and high mechanical strength. DETAILED DESCRIPTION

[0052] The inventors of the present application have repeatedly conducted in-depth research to achieve the above-mentioned purpose, and as a result, found that by using a hydrogen polysiloxane of a specific structure in an addition-curable fluorosilicone composition that is liquid at 23°C, a fluorosilicone rubber with good curability and mechanical strength can be obtained. It was further found that the liquid addition-curable fluorosilicone composition is suitable as a material for casting molding, compression molding and injection molding, thereby completing the first embodiment of the present invention. Specifically, the following fluorosilicone composition, fluorosilicone rubber and molded products thereof are provided.

[0053] That is, the first embodiment of the present invention is an addition-curable fluorosilicone composition, characterized in that it contains:

[0054] (A) a vinyl-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1),

[0055] [Chemical formula 7]

[0056]

[0057] In the general formula (1), R 1 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800;

[0058] (B) a branched organohydrogenpolysiloxane represented by the following formula (3) having three or more silicon-bonded hydrogen atoms in one molecule, wherein the number of hydrogen atoms bonded to silicon atoms in the component (B) is 0.5 to 10 per silicon-bonded vinyl group in the composition,

[0059] [Chemical formula 8]

[0060]

[0061] In the above formula (3), R 4are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1 is a number of 2≤x1≤4, x2 is an integer of 0≤x2≤20, x3 is an integer of 0≤x3≤20 and satisfies 0≤x2+x3≤20, y1 is an integer of 0≤y1≤30, z1 is an integer of 0≤z1≤10, y2 is an integer of 0≤y2≤30, z2 is an integer of 0≤z2≤10, and z1+z2>0;

[0062] (C) an addition reaction catalyst in a catalytic amount; and

[0063] (D) a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (2), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A);

[0064] [Chemical formula 9]

[0065]

[0066] In the above general formula (2), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, and R 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20,

[0067] The addition-curable fluorosilicone composition is in a liquid state at 23°C.

[0068] In addition, the fluorosilicone composition of the first embodiment of the present invention contains a linear polysiloxane as a main agent, and the main chain of the linear polysiloxane is a repeating structure of a diorganosiloxane unit having a fluoroalkyl group. On the other hand, a general dimethyl silicone composition uses a linear dimethyl polysiloxane having a repeating structure of a dimethyl siloxane unit as a main agent. In this respect, the fluorosilicone composition of the first embodiment of the present invention is essentially different from the dimethyl silicone composition.

[0069] As described above, there is also a need to develop a liquid addition-curable fluorosilicone composition that has very good curability and excellent storage stability and can form a fluorosilicone rubber that can maintain mechanical strength.

[0070] The inventors of the present application have repeatedly conducted in-depth studies on the above technical problems, and as a result, found that by using an alkenyl-containing organopolysiloxane of a specific structure and a hydrogenpolysiloxane of a specific structure in an addition-curable fluorosilicone composition that is liquid at 23°C, a liquid addition-curable fluorosilicone composition can be obtained, which has good curability and can form a fluorosilicone rubber that can maintain mechanical strength. It was further found that the liquid addition-curable fluorosilicone composition is suitable as a material for casting molding, compression molding and injection molding. Based on the above findings, the inventors of the present application completed the second solution of the present invention.

[0071] That is, the second embodiment of the present invention is an addition-curable fluorosilicone composition, which is a liquid addition-curable fluorosilicone composition, characterized in that it contains:

[0072] (A') an alkenyl group-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1A),

[0073] [Chemical formula 10]

[0074]

[0075] In the general formula (1A), R 1 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800;

[0076] (B') an organohydrogenpolysiloxane having 3 to 5 silicon-bonded hydrogen atoms in one molecule represented by the following general formula (2A), wherein the number of hydrogen atoms bonded to silicon atoms in the component (B') is 0.5 to 10 per silicon-bonded alkenyl group in the composition,

[0077] [Chemical formula 11]

[0078]

[0079] In the above general formula (2A), R 4are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf' is independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1' is an integer of 3≤x1'≤5, x2' and x3' are integers of 0≤x2'+x3'≤20, y1' is an integer of 0≤y1'≤30, y2' is an integer of 0≤y2'≤30, z1' is an integer of 0≤z1'≤10, z2' is an integer of 0≤z2'≤10, w is 0<w≤10, and x2', x3', y1', y2', z1' and z2' are not 0 at the same time;

[0080] (C') an addition reaction catalyst in a catalytic amount; and

[0081] (D') a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (3A), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A');

[0082] [Chemical formula 12]

[0083]

[0084] In the above general formula (3A), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, R 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20,

[0085] The addition-curable fluorosilicone composition is in a liquid state at 23°C.

[0086] Furthermore, a second aspect of the present invention is also a fluorosilicone rubber characterized in that it is a cured product of the addition-curing fluorosilicone composition of the second aspect of the present invention.

[0087] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0088] [First option]

[0089] The addition-curable fluorosilicone composition of the first embodiment of the present invention is characterized in that it contains (A) a specific vinyl-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C., (B) a specific branched organohydrogenpolysiloxane having three or more silicon-bonded hydrogen atoms in one molecule, (C) an addition reaction catalyst, and (D) a reinforcing silica filler obtained by surface treatment with a specific organosilicon compound, and the addition-curable fluorosilicone composition is liquid at 23° C. The composition may further contain components other than the above-mentioned (A) to (D) components. These components are described below.

[0090] (A) Vinyl-containing organopolysiloxane

[0091] The component (A) is an organopolysiloxane represented by the following general formula (1) and having a viscosity of 100 to 500,000 mPa·s at 25°C.

[0092] [Chemical formula 13]

[0093]

[0094] In the general formula (1), R 1 Each of the Rf radicals is independently selected from an alkyl radical having 1 to 8 carbon atoms, an aryl radical having 6 to 12 carbon atoms, and an aralkyl radical having 7 to 12 carbon atoms; each of the Rf radicals is independently selected from a perfluoroalkyl radical having 1 to 10 carbon atoms and a perfluoropolyether radical having 3 to 30 carbon atoms; X is a divalent organic radical; m is an integer having 0 to 100; n is an integer having 1 to 800; and 5≤m+n≤800.

[0095] Preferred is a perfluoroalkyl group-containing organopolysiloxane represented by the following formula (1').

[0096] [Chemical formula 14]

[0097]

[0098] In formula (1'), R 1 They are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, k is an integer of 1 to 10, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800.

[0099] In the above general formula (1), R 1They may be independently selected from the following groups: alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, hexyl, cyclohexyl, etc.; aryl groups having 6 to 12 carbon atoms, such as phenyl, tolyl, etc.; aralkyl groups having 7 to 12 carbon atoms, such as benzyl, etc. Among them, alkyl groups having 1 to 8 carbon atoms are preferred, and methyl groups are particularly preferred.

[0100] In the general formula (1), Rf is independently a group selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms. Examples of the perfluoroalkyl group include the following.

[0101] C k F 2k+1 -

[0102] k is an integer ranging from 1 to 10.

[0103] Furthermore, examples of the perfluoropolyether group include the following formulas.

[0104] [Chemical formula 15]

[0105]

[0106] s and t are integers ranging from 1 to 9 respectively.

[0107] In addition, in the above-mentioned general formula (1), X is a divalent organic group. X acts as a spacer, and it connects the main chain of the straight-chain vinyl-containing organopolysiloxane of the (A) component and the Rf group of the side chain, and can adjust the interaction between the Rf group or the Rf group and other molecules, so that the characteristics such as the hydrocarbon solvent durability of the cured product become the desired characteristics. The divalent organic group is not particularly limited, and can be set to an alkylene group with 2 to 4 carbon atoms, and the hydrogen atoms of a part of the alkylene group can be replaced by fluorine atoms, etc., and can also have an oxygen atom, an ester bond or an amide bond in the divalent organic group or at the end.

[0108] Examples of the divalent organic group include divalent organic groups such as those shown below.

[0109] [Chemical formula 16]

[0110]

[0111] * is bonded to the Rf group, ** is an atomic bond bonded to the silicon atom.

[0112] As the Rf-X group, preferably C k F 2k+1 -CH2CH2 group (k is an integer of 1 to 10), more preferably 3,3,3-trifluoropropyl group (k is 1).

[0113] m is an integer of 0 to 100, preferably an integer of 0 to 50, more preferably an integer of 0 to 30, further preferably an integer of 0 to 20, and most preferably an integer of 0 to 10. n is an integer of 1 to 800, preferably an integer of 5 to 750, more preferably an integer of 10 to 650, further preferably an integer of 50 to 650, and most preferably an integer of 100 to 650. Furthermore, (m+n) is an integer of 5≤m+n≤800, preferably an integer of 10≤m+n≤680, more preferably an integer of 60≤m+n≤680, and further preferably an integer of 120≤m+n≤680.

[0114] Relative to the total siloxane units in the molecule (particularly the total of the bifunctional siloxane units constituting the main chain (i.e., n+m)), the number of siloxane units having a fluoroalkyl group (i.e., the value of n) is preferably 10 mol% or more, more preferably 20 mol% or more, and particularly preferably 30 to 100 mol%. The upper limit is not particularly limited, as long as it is 100 mol% or less, and can be 95 mol% or less, 90 mol% or less, or 80 mol% or less. As long as it is within this range, it is possible to have excellent hydrocarbon solvent durability, so it is preferred.

[0115] The viscosity of the (A) organopolysiloxane is characterized in that the value at 25°C is in the range of 100 to 500,000 mPa·s, and more preferably in the range of 300 to 100,000 mPa·s. As long as it is within this range, the physical properties of the cured product are good, and the operability of the composition is also good. Furthermore, if the viscosity is less than 100 mPa·s, the strength of the resulting cured product will become insufficient, and if it exceeds 500,000 mPa·s, the operability of the composition will decrease, so it is not preferred. In addition, in the first embodiment of the present invention, the viscosity is a value measured by the method described in Japanese Industrial Standard JIS K 7117-1:1999 and using a rotational viscometer. The degree of polymerization of the (A) organopolysiloxane is a value that makes the viscosity at 25°C within the above range.

[0116] (B) Organohydrogenpolysiloxane

[0117] The component (B) is a branched organic hydrogen polysiloxane represented by the following formula (3) having three or more silicon-bonded hydrogen atoms in one molecule. The organic hydrogen polysiloxane reacts with the component (A) by a hydrosilylation addition reaction and acts as a curing agent (crosslinking agent). The molecular structure of the component (B) is a branched siloxane with terminal hydrogen modification. By including the organic hydrogen siloxane, the fluorosilicone composition cures quickly and its fluorosilicone rubber cured product can be strengthened.

[0118] [Chemical formula 17]

[0119]

[0120] In the above formula (3), R 4 Each of them is independently a group selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf is independently a group selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, and X is a divalent organic group. x1 is a number of 2≤x1≤4, x2 is an integer of 0≤x2≤20, x3 is an integer of 0≤x3≤20 and satisfies 0≤x2+x3≤20, y1 is an integer of 0≤y1≤30, z1 is an integer of 0≤z1≤10, y2 is an integer of 0≤y2≤30, z2 is an integer of 0≤z2≤10, and z1+z2>0.

[0121] The monovalent organic group R bonded to the silicon atom other than the hydrogen atom bonded to the silicon atom 4 It is a group selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, and can be exemplified by an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, which does not contain an aliphatic unsaturated bond such as an alkenyl group. For example, alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl, phenethyl, and phenylpropyl, etc., preferably methyl. The number of silicon atoms in one molecule of component (B) ((x1+x2+x3+y1+y2+z1+z2) or degree of polymerization) is preferably 4 to 60, more preferably 4 to 50, and even more preferably 4 to 40.

[0122] The monovalent organic group Rf bonded to the silicon atom other than the hydrogen atom bonded to the silicon atom is a group selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, and examples thereof include the groups shown in Rf of the above formula (1). A perfluoroalkyl group is preferred, and a trifluoromethyl group is more preferred.

[0123] X is a divalent organic group, and examples thereof include the groups shown as X in the above formula (1).

[0124] In addition, as the Rf-X group, C k F 2k+1 -CH2CH2 group (k is an integer of 1 to 10), more preferably 3,3,3-trifluoropropyl group (k is 1).

[0125] x1 is a number of 2≤x1≤4, x2 is an integer of 0≤x2≤20, x3 is an integer of 0≤x3≤20 and satisfies 0≤x2+x3≤20, y1 is an integer of 0≤y1≤30, z1 is an integer of 0≤z1≤10, y2 is an integer of 0≤y2≤30, z2 is an integer of 0≤z2≤10, and z1+z2>0. Furthermore, x2, x3, y1, y2, z1 and z2 are not 0 at the same time. Since z1+z2>0, the branched organohydrogenpolysiloxane represented by the above formula (3) contains one or more z1 units or z2 units as T units.

[0126] (B) Specific examples of the component include the following branched organohydrogenpolysiloxanes, but the present invention is not limited thereto.

[0127] [Chemical formula 18]

[0128]

[0129] The component (B) may be in liquid form at room temperature (25° C.). The viscosity of the component (B) at 25° C. is preferably 0.1 to 1,000 mPa·s, more preferably 0.5 to 500 mPa·s, and even more preferably 1 to 200 mPa·s. When the viscosity is within this range, the workability is good.

[0130] The amount of component (B) is such that the number of hydrogen atoms bonded to silicon atoms in component (B) is 0.5 to 10 relative to each silicon-atom-bonded vinyl group in the composition. In other words, it is such that the number ratio of silicon-atom-bonded hydrogen atoms (silicon hydrogen groups) in component (B) to one silicon-atom-bonded vinyl group (SiVi group) in the composition is 0.5 to 10, preferably 1 to 5. If the amount of component (B) is less than the above lower limit, the resulting composition will not be fully cured. In addition, if the blending amount of component (B) exceeds the above upper limit, the heat resistance of the resulting silicone rubber will become extremely poor. In addition, when a vinyl-containing silicon compound such as a vinyl-containing organosiloxane other than component (A) described later is included, the number ratio of silicon-atom-bonded hydrogen atoms in component (B) to the number of vinyl groups bonded to silicon atoms in the composition only needs to satisfy the above range.

[0131] The component (B) may be used alone or in combination of two or more.

[0132] Furthermore, the branched organohydrogenpolysiloxane represented by the above formula (3) may contain a hydroxyl group and / or an alkoxy group in the molecule. Specifically, the hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms may be contained in a range of 20 mol% or less of the total substituents of the above organopolysiloxane. Specific examples of the alkoxy group having 1 to 6 carbon atoms include: methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, pentyloxy, neopentyloxy, hexyloxy, etc., and in particular, methoxy, ethoxy, and isopropoxy.

[0133] (C) Addition reaction catalyst

[0134] The addition reaction catalyst of component (C) can be any catalyst as long as it promotes the addition reaction of the vinyl group in the composition with the hydrogen atom bonded to the silicon atom in component (B). Generally speaking, platinum group metal catalysts can be used. For example, platinum, palladium, rhodium, etc.; and platinum group metals or their compounds such as chloroplatinic acid, alcohol-modified chloroplatinic acid, chloroplatinic acid and olefins, vinyl siloxane or acetylene compounds, tetrakis(triphenylphosphine)palladium, tris(triphenylphosphine)rhodium chloride, etc., are listed, and platinum compounds are particularly preferred. Component (C) can be used alone or in combination of two or more.

[0135] The amount of component (C) added may be an effective amount (catalytic amount) as a catalyst, and is generally 0.5 to 1,000 ppm, preferably 1 to 500 ppm, and more preferably 10 to 100 ppm, relative to the amount of component (A), calculated as a catalyst metal element (platinum group metal element) on a mass basis. If this range is satisfied, the reaction rate of the addition reaction will be appropriate, and the heat resistance of the cured product will be good.

[0136] (D) Reinforcing silica filler

[0137] The component (D) is reinforcing silica obtained by surface treatment with a linear organic silicon compound having silanol groups at both ends of the molecular chain represented by the following formula (2).

[0138] [Chemical formula 19]

[0139]

[0140] In the above formula (2), R 3 Each of them is independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms. For example, the group 1 Examples described above. Methyl is preferred. 2 For the above R 3or 3,3,3-trifluoropropyl, and at least one R 2 p is an integer of 1≤p≤20, preferably an integer of 3 to 9.

[0141] In the first embodiment of the present invention, the reinforcing silica filler is necessary to impart mechanical strength to the silicone rubber obtained. If the organosilicon compound represented by the above formula (2) does not have a 3,3,3-trifluoropropyl group, the tensile strength, elongation at break and compression set of the obtained cured product are poor.

[0142] By containing a reinforcing silica filler obtained by surface-treating a linear organic silicon compound having both molecular chain ends blocked with silanol groups, the viscosity of the present composition and the compression set of the rubber after heat curing can be reduced.

[0143] As the reinforcing silica filler, any of those conventionally used in silicone rubber compositions can be used, and suitable examples include precipitated silica (wet silica), fumed silica (dry silica), and calcined silica. Fumed silica is particularly suitable.

[0144] The (D) component is obtained by pre-surface-treating the surface-untreated silica with the organosilicon compound of the above formula (2). Alternatively, the surface-untreated silica can be kneaded with a polysiloxane component (i.e., the (A) component), and the organosilicon compound of the above formula (2) can be added, preferably heated and mixed in the presence of a small amount of water to perform surface treatment in the mixture. In addition, the surface-untreated silica used in the first embodiment of the present invention refers to silica that has not been surface-treated with the organosilicon compound of the above formula (2), and can be dry silica obtained by surface treatment with dimethyldichlorosilane or the like (for example, AEROSIL R-974, etc.). Preferably, the surface of the dry silica obtained by surface treatment with dimethyldichlorosilane or the like is further treated with the organosilicon compound of the above formula (2).

[0145] Regarding the treatment amount when the silicon dioxide is surface-treated with the organosilicon compound of the above formula (2), it is preferred to use 1 to 30 parts by mass of the organosilicon compound of the above formula (2) for surface treatment, and it is particularly preferred to use 2 to 20 parts by mass of the organosilicon compound of the above formula (2) for surface treatment relative to 40 parts by mass of the silicon dioxide before the surface treatment with the organosilicon compound of the above formula (2).

[0146] In addition, an organosilane or organosilazane other than the organosilicon compound of the above formula (2) may be used as a surface treatment agent. Examples of organosilanes include: chlorosilanes such as trimethylchlorosilane, dimethyldichlorosilane, dimethylvinylchlorosilane, and trivinylchlorosilane; alkoxysilanes such as methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, trimethylmethoxysilane, triethylmethoxysilane, and vinyltri(methoxyethoxy)silane; silazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane, and 1,3-divinyl-1,1,3,3-tetramethyldisilazane, etc., among which hexamethyldisilazane and 1,3-divinyl-1,1,3,3-tetramethyldisilazane are preferred. The surface treatment is preferably performed with 0.1 to 15 parts by mass, and particularly preferably 0.1 to 10 parts by mass, of the organosilane or organosilazane relative to 40 parts by mass of the surface-untreated silica.

[0147] The specific surface area of ​​silicon dioxide before surface treatment with the organosilicon compound of the above formula (2) calculated by the BET method is 50 m 2 / g or more, preferably 100 to 400 m 2 / g, more preferably 150~350m 2 / g. As long as the specific surface area is 50m 2 / g or more, sufficient strength can be obtained and the appearance of the rubber molded product will also be improved. 2 The specific surface area of ​​the surface-treated silica calculated by the BET method may also be within the above range.

[0148] The amount of component (D) is 10 to 60 parts by mass, preferably 15 to 55 parts by mass, relative to 100 parts by mass of component (A). If the amount is less than the lower limit, the silicone rubber obtained does not have sufficient rubber strength, while if the amount exceeds the upper limit, it becomes difficult to incorporate into the composition.

[0149] Other Ingredients

[0150] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention may contain other components other than the above-mentioned (A) to (D) components as required. Other components include, for example, conductive agents such as carbon black, conductive zinc oxide, metal powder, nitrogen-containing compounds, acetylene compounds such as ethynylcyclohexanol, phosphorus compounds, nitrile compounds, carboxylates, tin compounds, mercury compounds, sulfur compounds and other hydrosilylation reaction control agents, heat resistance imparting agents such as iron oxide and cerium oxide, triazole compounds, benzotriazole derivatives such as benzotriazole silane and other compression set enhancers, internal mold release agents such as dimethyl silicone oil, adhesion imparting agents, thixotropy imparting agents, etc. However, the liquid addition-curable fluorosilicone composition of the first embodiment of the present invention does not contain isocyanuric acid derivatives having three trialkoxy groups in one molecule.

[0151] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention can be prepared by uniformly mixing the above components (A) to (D) and any optional components as required using a general mixer such as a kneader, a planetary mixer, a kneader, or the like.

[0152] The composition of the first embodiment of the present invention is characterized in that it is liquid at 23°C. Here, "liquid at 23°C" means that it has a certain volume at 23°C, but its shape changes with the shape of the container (it has fluidity). From the viewpoint of operability, etc., at 23°C, the shear rate is 10s -1 The viscosity at the time of shearing is preferably 1,500 Pa·s or less, more preferably 100 to 1,200 Pa·s, and further preferably 200 to 1,100 Pa·s. When the viscosity exceeds 1,500 Pa·s, it takes time to supply the material during injection, compression, and injection molding, and productivity is significantly reduced. In addition, in the first embodiment of the present invention, the viscosity at the above shear rate is measured using a precision rotational viscometer (manufactured by ThermoFisher Scientific).

[0153] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention can also be a two-component type. In this case, the component (B) as a crosslinking agent and the component (C) as an addition reaction catalyst can be divided in such a way that the components are not mixed in the same composition (liquid A or liquid B). For example, a two-component composition consisting of a liquid A containing components (A), (C) and (D) and a liquid B containing components (A), (B) and (D) can be prepared, and it is preferred that the composition be prepared in such a way that equal mass or equal volume can be mixed.

[0154] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention can be applied to various molding methods such as casting molding, compression molding, injection molding, etc. The molding method of fluorosilicone rubber by casting molding, compression molding or injection molding is described in detail below.

[0155] During casting, the liquid addition-curing fluorosilicone composition is divided into a two-component type of liquid A and liquid B. Regarding the material divided into two components, the liquid A and liquid B are mixed in equal amounts, injected into a metal mold, heated and cured in a constant temperature bath, and molded into silicone rubber. During compression molding, the metal mold is set in a compressor such as a press, and the above-mentioned liquid A and liquid B are mixed in equal amounts in the same way as casting, injected into the mold for heating and curing, and molded into silicone rubber. During injection molding, liquid A and liquid B are supplied to the metering device from the material supply pump. Liquid A and liquid B are converged from the metering device through the material supply pipeline in an equal ratio. The material is mixed in the spiral part and the cylinder part of the molding machine body. Then, it is injected into the mold, heated and cured in the mold, and molded into silicone rubber.

[0156] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention is particularly suitable for a liquid silicone rubber injection molding system (LIMS). LIMS is a molding processing system that combines a liquid silicone rubber with excellent properties and a molding machine that can precisely and stably inject it. It can be automated from mixing to molding, and can simplify and shorten the steps, and can also make it easy to mold high-quality products. In this molding method, the composition of the first embodiment of the present invention has the following advantages. That is, (i) the curing speed is fast and the molding time can be shortened, so the process can be shortened; (ii) since the material is in liquid form, it can be molded using a low injection pressure, and it can also cope with the molding of precision parts, so productivity will be improved; (iii) it can cope with burr-free and runner-free molding, and the demolding property after curing is also good, so the molding process can be automated; (iv) there are no by-products produced by the curing reaction, and there is no need to handle waste materials through burr-free and runner-free molding, so environmentally friendly manufacturing can be carried out.

[0157] The first embodiment of the present invention provides a cured product of the above-mentioned addition-cured fluorosilicone composition, namely, a fluorosilicone rubber. As long as it is such a fluorosilicone rubber, it can maintain good mechanical strength. The curing of the composition can be carried out according to known techniques, and the curing method and conditions are not particularly limited.

[0158] The curing molding (primary curing) conditions of the liquid addition-curing fluorosilicone composition are the same as those of the known addition-curing reaction-type silicone composition, and can be cured by heating under the following conditions: the curing temperature is 80 to 220°C, especially 120 to 200°C; the curing time is 3 seconds to 10 minutes, especially 5 seconds to 5 minutes. If necessary, the formed cured product can be post-cured (secondary cured) at 180 to 220°C for about 30 minutes to 6 hours.

[0159] The cured product (silicone rubber) obtained by the liquid addition-curing fluorosilicone composition of the present application has a compression permanent deformation of 10% or less after compression at 180°C for 22 hours based on the Japanese Industrial Standard JIS K 6249:2003, and a tensile strength of mechanical strength of 5.0 MPa or more. Alternatively, the compression permanent deformation after compression at 180°C for 22 hours at a compression rate of 25% based on Japanese Industrial Standard JIS K 6249:2003 can be 15% or less, preferably 10% or less. When the compression permanent deformation is 10% or less, the cured product can be used as a sealing material, an O-ring or a gasket (packing) and other parts (molded body). Regarding mechanical strength, from the perspective of practical strength of rubber molded products, the tensile strength can be 4.5 MPa or more, preferably 5.0 MPa or more.

[0160] Furthermore, a first aspect of the present invention provides a fluorosilicone rubber molded product, characterized in that it is a molded body of the above-mentioned fluorosilicone rubber.

[0161] The fluorosilicone rubber molded article obtained by heat-curing the liquid addition-curable fluorosilicone composition of the first embodiment of the present invention has excellent gasoline resistance and oil resistance, and can be applied to rubber parts for aircraft and vehicles, printer parts, etc. In recent years, it can also be applied to moving parts based on its sebum resistance, and can also be applied to sealing parts for fuel cell vehicles based on its acid resistance.

[0162] [Second Option]

[0163] [Liquid addition-curable fluorosilicone composition]

[0164] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention generally comprises (A') alkenyl group-containing organopolysiloxane, (B') organohydrogenpolysiloxane, (C') addition reaction catalyst, and (D') reinforcing silica filler.

[0165] Hereinafter, each component in the liquid addition-curable fluorosilicone composition according to the second embodiment of the present invention will be described in more detail.

[0166] (A') alkenyl-containing organopolysiloxane

[0167] The component (A') is an alkenyl (vinyl) group-containing organopolysiloxane represented by the following general formula (1A) and having a viscosity at 25°C of 100 to 500,000 mPa·s.

[0168] [Chemical formula 20]

[0169]

[0170] In the general formula (1A), R 1 Each of the Rf groups is independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms; each of the Rf groups is independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms; X is a divalent organic group; m is an integer of 0 to 100; n is an integer of 1 to 800; and 5≤m+n≤800.

[0171] The component (A') is preferably a perfluoroalkyl group-containing organopolysiloxane represented by the following formula (1A').

[0172] [Chemical formula 21]

[0173]

[0174] In formula (1A'), R 1 They are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 12 carbon atoms, k is an integer of 1 to 10, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800.

[0175] In the above general formula (1A) and formula (1A'), R 1 Each of them is independently selected from the following groups: alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, hexyl and cyclohexyl; aryl groups having 6 to 12 carbon atoms, such as phenyl and tolyl; and aralkyl groups having 7 to 12 carbon atoms, such as benzyl. Among them, alkyl groups having 1 to 8 carbon atoms are preferred, and methyl groups are particularly preferred.

[0176] In the general formula (1A), Rf is independently a group selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms. Examples of the perfluoroalkyl group include the following.

[0177] C k F 2k+1 -

[0178] k is an integer ranging from 1 to 10.

[0179] Furthermore, examples of the perfluoropolyether group include the following formulas.

[0180] [Chemical formula 22]

[0181]

[0182] s and t are integers ranging from 1 to 9 respectively.

[0183] In the general formula (1A), X is a divalent organic group. Examples of the divalent organic group include divalent organic groups of the following formula.

[0184] [Chemical formula 23]

[0185]

[0186] * is an atomic bond bonded to the Rf group, and ** is an atomic bond bonded to the silicon atom.

[0187] m is an integer of 0 to 100, preferably an integer of 0 to 50, more preferably an integer of 0 to 30, further preferably an integer of 0 to 20, and most preferably an integer of 0 to 10. n is an integer of 1 to 800, preferably an integer of 5 to 750, more preferably an integer of 10 to 650, further preferably an integer of 50 to 650, and most preferably an integer of 100 to 650. Furthermore, (m+n) is an integer of 5≤m+n≤800, preferably an integer of 10≤m+n≤680, more preferably an integer of 60≤m+n≤680, and further preferably an integer of 120≤m+n≤680.

[0188] The viscosity of the organopolysiloxane of the (A') component is characterized in that the value at 25°C is in the range of 100 to 500,000 mPa·s, and more preferably in the range of 300 to 100,000 mPa·s. As long as it is within this range, the physical properties of the cured product are good, and the operability of the composition is also good. Furthermore, if the viscosity is less than 100 mPa·s, the strength of the resulting cured product will become insufficient, and if it exceeds 500,000 mPa·s, the operability of the composition will decrease, so it is not preferred. In addition, in the second embodiment of the present invention, the viscosity is a value measured by the method described in Japanese Industrial Standard JIS K 7117-1:1999 and using a rotational viscometer. The degree of polymerization of the (A') organopolysiloxane is a value that makes the viscosity at 25°C within the above range.

[0189] Relative to the total siloxane units in the molecule (particularly the total of the bifunctional siloxane units constituting the main chain (i.e., n+m)), the number of siloxane units with a perfluoroalkyl group or a perfluoropolyether group (i.e., the value of n) is preferably 10 mol % or more, more preferably 20 mol % or more, and particularly preferably 30 to 100 mol %. The upper limit is not particularly limited, as long as it is below 100 mol %, and can be below 95 mol %, below 90 mol % or below 80 mol %. As long as it is within this range, it is possible to have excellent hydrocarbon solvent durability, so it is preferred.

[0190] In addition, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention contains a linear polysiloxane as a main agent, and the main chain of the linear polysiloxane is a repeating structure of a diorganosiloxane unit having a perfluoroalkyl group or a perfluoropolyether group. On the other hand, a general dimethyl silicone composition uses a linear dimethyl polysiloxane having a main chain structure of a repeating dimethyl siloxane unit as a main agent. In this respect, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention is essentially different from the dimethyl silicone composition.

[0191] (B') Organohydrogenpolysiloxane

[0192] The organohydrogenpolysiloxane as the component (B′) is an organohydrogenpolysiloxane represented by the following formula (2A) and having 3 to 5 silicon-bonded hydrogen atoms in one molecule.

[0193] [Chemical formula 24]

[0194]

[0195] In the above formula (2A), R 4 Each of them is independently a group selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf' is independently a group selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, and X is a divalent organic group. x1' is an integer of 3≤x1'≤5, x2' and x3' are integers of 0≤x2'+x3'≤20, y1' is an integer of 0≤y1'≤30, y2' is an integer of 0≤y2'≤30, z1' is an integer of 0≤z1'≤10, z2' is an integer of 0≤z2'≤10, w is 0<w≤10, and x2', x3', y1', y2', z1' and z2' are not 0 at the same time.

[0196] In the above formula (2A), w is 0<w≤10, so the organohydrogen polysiloxane as component (B') must contain "SiO 4 / 2 "Unit, that is, Q unit.

[0197] The organohydrogenpolysiloxane reacts with the component (A′) through a hydrosilylation reaction to function as a curing agent (crosslinking agent).

[0198] The molecular structure of the component (B') is preferably a branched siloxane with terminal hydrogen modification. By including such an organohydrogensiloxane, the silicone rubber cured product can be cured quickly and have a high strength.

[0199] The organohydrogenpolysiloxane as the component (B′) is preferably an organohydrogenpolysiloxane having 3 to 5 silicon-bonded hydrogen atoms in one molecule represented by the following formula (2A′).

[0200] [Chemical formula 25]

[0201]

[0202] In the above formula (2A'), R 4 They are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, and X is a divalent organic group. x1' is an integer of 3≤x1'≤5, x2' and x3' are integers of 0≤x2'+x3'≤20, y1' is an integer of 0≤y1'≤30, y2' is an integer of 0≤y2'≤30, w is 0<w≤10, k is an integer of 1 to 10, and x2', x3', y1' and y2' are not 0 at the same time.

[0203] As a monovalent organic group R bonded to a silicon atom other than a hydrogen atom bonded to a silicon atom 4 , examples include: unsubstituted or substituted monovalent hydrocarbon groups having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, not containing aliphatic unsaturated bonds such as alkenyl groups, i.e., alkyl groups; aryl groups having 6 to 12 carbon atoms and not containing aliphatic unsaturated bonds; and aralkyl groups having 7 to 12 carbon atoms and not containing aliphatic unsaturated bonds. Examples include: alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; and aralkyl groups such as benzyl, phenethyl, and phenylpropyl, preferably methyl.

[0204] The number of silicon atoms (or degree of polymerization) in one molecule of the component (B′) is preferably 4 to 60, more preferably 4 to 50, and even more preferably 4 to 40.

[0205] The monovalent organic group Rf' bonded to the silicon atom other than the hydrogen atom bonded to the silicon atom is a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, preferably a perfluoroalkyl group, more preferably a 3,3,3-trifluoropropyl group.

[0206] The component (B') may be in liquid form at room temperature (25°C). The viscosity of the component (B') at 25°C is preferably 0.1 to 1,000 mPa·s, more preferably 0.5 to 500 mPa·s, and even more preferably 1 to 200 mPa·s. When the viscosity at 25°C is 0.1 to 1,000 mPa·s, good workability can be achieved.

[0207] The amount of component (B') is an amount that makes the ratio of the number of silicon-bonded hydrogen atoms in component (B') to one silicon-bonded alkenyl group in the composition of the second embodiment of the present invention be within the range of 0.5 to 10, and preferably makes the ratio of the number of silicon-bonded hydrogen atoms in component (B') to one silicon-bonded alkenyl group in the composition of the second embodiment of the present invention be within the range of 1 to 5. If the amount of component (B') is less than the above lower limit, the resulting composition will not be fully cured. In addition, if the blending amount of component (B') exceeds the above upper limit, the heat resistance of the resulting silicone rubber will become extremely poor. In addition, when an alkenyl-containing organosiloxane other than component (A') described later is included, the ratio of the number of silicon-bonded hydrogen atoms in component (B') to the number of alkenyl groups bonded to silicon atoms in the composition only needs to satisfy the above range.

[0208] The component (B') may be used alone or in combination of two or more thereof. Furthermore, the component (B') may be used in combination of two or more thereof with another organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms in one molecule.

[0209] (C') Addition reaction catalyst

[0210] The addition reaction catalyst of the component (C') may be any catalyst as long as it promotes the addition reaction of the alkenyl (vinyl) in the component (A') and the hydrogen atom bonded to the silicon atom in the component (B'). Generally speaking, platinum group metal catalysts can be used. For example, platinum, palladium, rhodium, etc., and platinum group metals or compounds thereof such as chloroplatinic acid, alcohol-modified chloroplatinic acid, chloroplatinic acid and olefins, vinyl siloxane or acetylene compounds, tetrakis(triphenylphosphine)palladium, tris(triphenylphosphine)rhodium chloride, etc. are listed, and platinum compounds are particularly preferred.

[0211] The component (C') may be used alone or in combination of two or more.

[0212] The amount of component (C') added may be an effective amount (catalytic amount) as a catalyst, and is generally 0.5 to 1,000 ppm, preferably 1 to 500 ppm, and more preferably 10 to 100 ppm, relative to the amount of component (A'), calculated as a catalyst metal element (platinum group metal element) on a mass basis. If this range is satisfied, the reaction rate of the addition reaction will be appropriate, and the heat resistance of the cured product will be good.

[0213] (D') Reinforcing silica filler

[0214] The component (D′) is reinforcing silica obtained by surface treatment with a linear organic silicon compound having silanol groups at both ends of the molecular chain represented by the following formula (3A).

[0215] [Chemical formula 26]

[0216]

[0217] In the above formula (3A), R 3 Each of them is independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, for example, the group 1 Examples described above. Methyl is preferred. 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 p is an integer of 1≤p≤20, preferably an integer of 3 to 9.

[0218] In the second embodiment of the present invention, the reinforcing silica filler is necessary to impart mechanical strength to the silicone rubber obtained. If the organosilicon compound represented by the above formula (3A) does not have a 3,3,3-trifluoropropyl group, the tensile strength, elongation at break and compression set of the obtained cured product are poor.

[0219] By containing a reinforcing silica filler obtained by surface-treating a linear organic silicon compound having both molecular chain ends blocked with silanol groups, the viscosity of the present composition and the compression set of the rubber after heat curing can be reduced.

[0220] As the reinforcing silica filler, any of those conventionally used in silicone rubber compositions can be used, and suitable examples include precipitated silica (wet silica), fumed silica (dry silica), and calcined silica. Fumed silica is particularly suitable.

[0221] The (D') component is obtained by pre-surface-treating the surface-untreated silica with the organosilicon compound of the above formula (3A). Alternatively, the surface-untreated silica can be kneaded with a polysiloxane component (i.e., the (A') component), and the organosilicon compound of the above formula (3A) can be added, preferably heated and mixed in the presence of a small amount of water to perform surface treatment in the mixture. In addition, the surface-untreated silica preferably used in the second embodiment of the present invention can be dry silica (e.g., AEROSIL R-974, etc.) obtained by surface treatment with dimethyldichlorosilane, etc. Preferably: the surface of the dry silica obtained by surface treatment with dimethyldichlorosilane, etc. is further treated with the organosilicon compound of the above formula (3A).

[0222] Regarding the treatment amount when using the organosilicon compound of the above formula (3A) to treat the silicon dioxide surface, it is preferred to use 1 to 30 parts by mass of the organosilicon compound of the above formula (3A) for surface treatment, and it is particularly preferred to use 2 to 20 parts by mass of the organosilicon compound of the above formula (3A) for surface treatment relative to 40 parts by mass of silicon dioxide before surface treatment with the organosilicon compound of the above formula (3A).

[0223] In addition, organosilanes or organosilazanes other than the organosilicon compound of the above formula (3A) may be used as surface treatment agents. Examples of organosilanes include: chlorosilanes such as trimethylchlorosilane, dimethyldichlorosilane, dimethylvinylchlorosilane, and trivinylchlorosilane; alkoxysilanes such as methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, trimethylmethoxysilane, triethylmethoxysilane, and vinyltri(methoxyethoxy)silane; silazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane, and 1,3-divinyl-1,1,3,3-tetramethyldisilazane, etc., among which hexamethyldisilazane and 1,3-divinyl-1,1,3,3-tetramethyldisilazane are preferred. The surface treatment is preferably performed with 0.1 to 15 parts by mass, and particularly preferably 0.1 to 10 parts by mass, of the organosilane or organosilazane relative to 40 parts by mass of the surface-untreated silica.

[0224] The specific surface area of ​​silicon dioxide before surface treatment with the organosilicon compound of the above formula (3A) calculated by the BET method was 50 m 2 / g or more, preferably 100 to 400 m 2 / g, more preferably 150~350m2 / g. As long as the specific surface area is 50m 2 / g or more, sufficient strength can be obtained and the appearance of the rubber molded product will also be improved. 2 The specific surface area of ​​the surface-treated silica calculated by the BET method may also be within the above range.

[0225] The amount of component (D') is 10 to 60 parts by mass, preferably 15 to 55 parts by mass, relative to 100 parts by mass of component (A'). If the amount is less than the lower limit, the resulting silicone rubber does not have sufficient rubber strength, while if it exceeds the upper limit, it becomes difficult to incorporate into the composition.

[0226] Other Ingredients

[0227] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention may contain other components in addition to the above-mentioned components (A') to (D') as necessary. The amount of the components to be added is not particularly limited.

[0228] Other components include, for example, carbon black, conductive zinc oxide, conductive agents such as metal powder, nitrogen-containing compounds, acetylene compounds, phosphorus compounds, nitrile compounds, carboxylates, tin compounds, mercury compounds, sulfur compounds and other hydrosilylation control agents, heat resistance imparting agents such as iron oxide and cerium oxide, triazole compounds, benzotriazole derivatives and other compression set enhancers, internal mold release agents such as dimethyl silicone oil, adhesion imparting agents, thixotropy imparting agents, etc. However, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention does not contain an isocyanuric acid derivative having three trialkoxy groups in one molecule.

[0229] [Preparation method]

[0230] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention can be prepared, for example, by uniformly mixing the above components (A') to (D') and any other optional components as required using a general mixer such as a kneader, planetary mixer, or kneader.

[0231] [Properties]

[0232] The composition of the second embodiment of the present invention is characterized in that it is liquid at 23° C. From the viewpoint of operability, the shear rate is 10 s at 23° C. -1The viscosity at the time of shearing is preferably 1,500 Pa·s or less, more preferably 100 to 1,200 Pa·s, and further preferably 200 to 1,100 Pa·s. As long as the viscosity is 1,500 Pa·s or less, it will not take too much time to supply the material during injection, compression and injection molding, and high productivity can be provided. In addition, in the second embodiment of the present invention, the viscosity at the above shear rate is measured using a precision rotational viscometer (manufactured by Thermo Fisher Scientific).

[0233] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention can also be a two-component type. In this case, for the component (B') as a crosslinking agent and the component (C') as an addition reaction catalyst, it is sufficient to appropriately divide the components so that they are not mixed in the same composition (liquid A or liquid B). For example, it can be a two-component composition consisting of a liquid A containing components (A'), (C') and (D') and a liquid B containing components (A'), (B') and (D'), and it is preferably prepared in a manner that allows equal mass or equal volume mixing.

[0234] [Fluorosilicone rubber]

[0235] The fluorosilicone rubber is a cured product of the addition-curing fluorosilicone composition of the second embodiment of the present invention.

[0236] The liquid addition-curable fluorosilicone composition of the second embodiment of the present invention can be applied to various molding methods such as casting molding, compression molding, injection molding, etc. The molding method of fluorosilicone rubber by casting molding, compression molding or injection molding is described in detail below.

[0237] During casting, the liquid addition-curable fluorosilicone composition is divided into two components, namely, liquid A and liquid B. The two-component materials (ingredients) are mixed in equal amounts, injected into a metal mold, and heated and cured in a constant temperature bath to form silicone rubber.

[0238] In the case of compression molding, a metal mold is placed in a compressor such as a press machine, and the above-mentioned liquid A and liquid B are mixed in equal amounts in the same manner as in cast molding, injected into the mold, heated and cured, and molded into silicone rubber.

[0239] During injection molding, liquid A and liquid B are supplied from the material supply pump to the dosing device. Liquid A and liquid B are equal in ratio and flow from the dosing device through the material supply pipeline. The materials are mixed in the spiral part and cylinder part of the molding machine body. Then, they are injected into the mold, heated and cured in the mold, and molded into silicone rubber.

[0240] The curing molding (primary curing) conditions of the liquid addition curing type fluorosilicone composition are the same as those of the known addition reaction curing type silicone composition, and can be cured by heating under the following conditions: the curing temperature is 80 to 220°C, especially 120 to 200°C; the curing time is 3 seconds to 10 minutes, especially 5 seconds to 5 minutes. If necessary, the formed cured product can be post-cured (secondary cured) at 180 to 220°C for about 30 minutes to 6 hours.

[0241] The cured product (silicone rubber) obtained from the liquid addition-curing fluorosilicone composition of the second embodiment of the present invention, i.e., the silicone rubber of the second embodiment of the present invention, can have a compression permanent deformation of 10% or less after compression at 180°C for 22 hours based on the Japanese Industrial Standard JIS K 6249:2003, and a tensile strength of mechanical strength of 5.0 MPa or more. Alternatively, the compression permanent deformation after compression at 180°C for 22 hours at a compression rate of 25% based on Japanese Industrial Standard JIS K 6249:2003 can be 15% or less, preferably 10% or less. When the compression permanent deformation is 10% or less, the cured product can be used as a sealing material, an O-ring, a gasket or other parts (molded body). With regard to mechanical strength, from the perspective of the practical strength of rubber molded products, the tensile strength is preferably 4.5 MPa or more, and more preferably 5.0 MPa or more.

[0242] The fluorosilicone rubber molded product (silicone rubber) obtained by heat-curing the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention has excellent gasoline resistance and oil resistance, and can be used for aircraft and vehicle rubber parts, printer parts, etc. In recent years, based on the sebum resistance, it can also be used for moving parts, and based on the acid resistance, it can also be used for fuel cell vehicle sealing parts.

[0243] Example

[0244] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples; however, the present invention is not limited to the following Examples.

[0245] The viscosities of the components (A) and (A') were measured at 25°C using a BH type rotational viscometer (rotor number 7, rotation speed 10 rpm).

[0246] The curability of the composition was measured by using a curability tester (rotorless-type disk rheometer, moving-die rheometer or MDR) at 130° C. for 3 minutes, with the 10% and 90% curing times (i.e., the time from the start of measurement at 130° C. from the time when 10% and 90% of the maximum torque value were applied within 3 minutes from the start of measurement at 130° C.) as T10 and T90 (seconds).

[0247] The hardness, tensile strength, elongation at break, and tear strength (angle) of the cured product were measured by the following methods.

[0248] The composition was press cured at 150°C for 10 minutes, and further vulcanized (post-cured) for a second time in a thermostatic chamber at 200°C for 4 hours. The hardness (A-type durometer hardness), tensile strength, elongation at break, and tear strength (angle) of the obtained cured product were measured based on the Japanese Industrial Standard JIS K6249:2003.

[0249] The compression set of the cured product was measured by the following method.

[0250] The composition was cured at 150°C for 15 minutes (pressed curing), and further vulcanized twice in a thermostatic chamber at 200°C for 4 hours (post-curing). The compression set of the obtained cured product after compression at 180°C for 22 hours at a compression rate of 25% was measured based on the description of Japanese Industrial Standard JIS K6249:2003.

[0251] <Examples 1 to 4 and Comparative Examples 1 and 2>

[0252] The components used in Examples 1 to 4 and Comparative Examples 1 and 2 are as follows.

[0253] Component (A): trifluoropropylmethylpolysiloxane (vinyl content: 4.6×10 -5 mol / g]

[0254] [Chemical formula 27]

[0255]

[0256] Component (D): Specific surface area calculated by BET method: 200 m 2 / g of fumed silica (AEROSIL R-974 manufactured by Nippon Aerosil Co., Ltd.) and an organic silicon compound represented by the following formula (5).

[0257] [Chemical formula 28]

[0258]

[0259] (B) Cross-linking agent:

[0260] (B-1) Methyl hydrogen polysiloxane represented by the following formula (6-1) [SiH group content: 0.0086 mol / g]

[0261] [Chemical formula 29]

[0262]

[0263] (B-2) Methyl hydrogen polysiloxane represented by the following formula (6-2) [SiH group content: 0.0020 mol / g]

[0264] [Chemical formula 30]

[0265]

[0266] (B-3) Methyl hydrogen polysiloxane represented by the following formula (6-3) [SiH group content: 0.0016 mol / g]

[0267] [Chemical formula 31]

[0268]

[0269] (B-4) Methyl hydrogen polysiloxane represented by the following formula (6-4) [viscosity: 0.06 Pa·s, SiH group content: 0.0049 mol / g]

[0270] [Chemical formula 32]

[0271]

[0272] (C) Platinum catalyst (Pt concentration: 0.5 mass %)

[0273] (Other ingredients)

[0274] Reaction control agent: ethynyl cyclohexanol

[0275] Compression set enhancer: Benzotriazole silane represented by the following formula (7)

[0276] [Chemical formula 33]

[0277]

[0278] Heat resistance imparting agent: cerium oxide

[0279] [Preparation Example 1]

[0280] At 25°C, 55 parts by mass of (A) trifluoropropylmethylpolysiloxane represented by the above formula (4) [vinyl content of 4.6×10 -5 mol / g], 40 parts by mass of the above-mentioned fumed silica as a reinforcing silica filler, 6 parts by mass of the organosilicon compound represented by the above formula (5), 0.5 parts by mass of water and 0.4 parts by mass of 1,3-divinyl-1,1,3,3-tetramethyldisilazane were mixed for 30 minutes, the temperature was raised to 160°C, and stirring was continued for 3 hours. Further, 60 parts by mass of trifluoropropylmethylpolysiloxane represented by the above formula (4) was added, and the mixture was mixed for 30 minutes to obtain a silicone rubber base A1. In addition, in the obtained silicone rubber base, the amount of component (D) was 35 parts by mass for every 100 parts by mass of component (A).

[0281] [Examples 1 to 4, Comparative Examples 1 and 2]

[0282] The silicone rubber composition was prepared using the blending amounts shown in the following Table 1. For the resulting composition, the viscosity was measured using the above conditions, and a cured product was made to measure the above general properties. The results are recorded in Table 1. In addition, the "Curing T10 / T90" column in the table shows the 10% and 90% curing times (seconds) calculated using the above measurement method, respectively, and the difference is shown in the "Curing T90-T10" column. The smaller the difference, the faster the curing. In addition, "SiH / SiVi" is the ratio of the number of SiH groups in component (B) to the number of SiVi groups in the composition.

[0283] [Table 1]

[0284]

[0285] As shown in Table 1 above, the cured product obtained from the liquid addition-curable fluorosilicone composition of the first embodiment of the present invention has good curability (fast curing) and excellent tensile strength and elongation at break. However, the fluorosilicone compositions of Comparative Examples 1 and 2 using the linear silicone (B-4) whose side chains are hydrogen-modified using the organosilicon compound of the first embodiment of the present invention have poor curability (slightly slow curing) and poor mechanical strength.

[0286] The liquid addition-curable fluorosilicone composition of the first embodiment of the present invention is suitable as a material for casting, compression molding and injection molding, and can contribute to the improvement of the productivity of molded products. In addition, the liquid addition-curable fluorosilicone composition of the first embodiment of the present invention has a low value of compression set after heat curing, and can be suitably used as a sealing material, an O-ring, a rubber molded body such as a gasket, etc.

[0287] <Examples 5 to 8, Comparative Example 3>

[0288] In Examples 5 to 8 and Comparative Example 3, the storage stability of the compositions was evaluated by the following method.

[0289] The composition was evaluated as "○" if the fluidity was maintained and the composition was in a liquid state after visual observation at 30°C for 3 days or at 30°C for 7 days, and as "×" if the composition was gelled.

[0290] The components used in the following Examples 5 to 8 and Comparative Example 3 are as follows.

[0291] Component (A'): trifluoropropylmethylpolysiloxane having a viscosity of 76.6 Pa·s at 25°C and having a vinyl content of 4.6 × 10 -5 mol / g]

[0292] [Chemical formula 34]

[0293]

[0294] (D') component: specific surface area calculated by BET method: 200 m 2 / g of fumed silica (AEROSIL R-974 manufactured by Nippon Aerosil Co., Ltd.) and an organic silicon compound represented by the following formula (5').

[0295] [Chemical formula 35]

[0296]

[0297] (B') Cross-linking agent:

[0298] (B'-1) Methyl hydrogen polysiloxane represented by the following formula (6-1') [SiH group content: 0.012 mol / g]

[0299] [Chemical formula 36]

[0300]

[0301] (B'-2) Methyl hydrogen polysiloxane represented by the following formula (6-2') [SiH group content: 0.0018 mol / g]

[0302] [Chemical formula 37]

[0303]

[0304] (B'-3) Methyl hydrogen polysiloxane represented by the following formula (6-3') [SiH group content: 0.0017 mol / g]

[0305] [Chemical formula 38]

[0306]

[0307] (B'-4) Methyl hydrogen polysiloxane represented by the following formula (6-4') [viscosity: 0.06 Pa·s, SiH group content: 0.0049 mol / g]

[0308] [Chemical formula 39]

[0309]

[0310] (B'-5) Crosslinking agent: methyl hydrogen polysiloxane represented by the following formula (6-5') [SiH group content: 0.086 mol / g]

[0311] [Chemical formula 40]

[0312]

[0313] (C') Platinum catalyst (Pt concentration: 0.5 mass %)

[0314] (Other ingredients)

[0315] Reaction control agent: ethynyl cyclohexanol

[0316] Compression set enhancer: Benzotriazole silane represented by the following formula (7)

[0317] [Chemical formula 41]

[0318]

[0319] Heat resistance imparting agent: cerium oxide

[0320] [Preparation Example 2]

[0321] At 25°C, 55 parts by mass of (A') trifluoropropylmethylpolysiloxane represented by the above formula (4') [vinyl content of 4.6 × 10 -5mol / g], 40 parts by mass of the above-mentioned fumed silica as a reinforcing silica filler, 6 parts by mass of the organosilicon compound represented by the above formula (5'), 0.5 parts by mass of water and 0.4 parts by mass of 1,3-divinyl-1,1,3,3-tetramethyldisilazane were mixed for 30 minutes, the temperature was raised to 160°C, and stirring was continued for 3 hours. Further, 60 parts by mass of trifluoropropylmethylpolysiloxane represented by the above formula (4') was added, and the mixture was mixed for 30 minutes to obtain a silicone rubber substrate A1'. In addition, in the obtained silicone rubber substrate, the amount of the component (D') was 35 parts by mass for every 100 parts by mass of the component (A').

[0322] [Examples 5 to 8 and Comparative Example 3]

[0323] The silicone rubber composition was prepared using the blending amounts shown in Table 2 below. The viscosity of the obtained composition was measured under the above conditions, and a cured product was prepared to measure the above general properties. These results are shown in Table 2.

[0324] [Table 2]

[0325]

[0326] As shown in Table 2, the curing properties of the liquid addition-curable fluorosilicone compositions of Examples 5 to 7 as examples of the second embodiment of the present invention are much faster than those of the compositions of Comparative Example 3 and Example 8, and the tensile strength and elongation at break of the cured products of the compositions of Examples 5 to 7 are superior to those of the cured products of the compositions of Comparative Example 3 and Example 8. In addition, the curing properties of the liquid addition-curable fluorosilicone composition of Example 8 as an example of the first embodiment of the present invention are faster than those of the composition of Comparative Example 3, and the tensile strength and elongation at break of the cured product of the composition of Example 8 are superior to those of the cured product of the composition of Comparative Example 3. However, the side chain of the organosilicon compound of the second embodiment of the present invention is hydrogen-modified and does not contain SiO 4 / 2 The fluorosilicone compositions of Comparative Example 3, which contain silicone units, have a slightly slow curing property and the mechanical strength of the cured products of these compositions is also poor. In addition, the storage stability of the liquid addition-curable fluorosilicone compositions of Examples 5 to 8, which are examples of the first and second embodiments of the present invention, is the same as or better than that of the conventional ones.

[0327] That is, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention is suitable as a material for casting, compression molding and injection molding, and can contribute to the improvement of the productivity of molded products. In addition, the liquid addition-curable fluorosilicone composition of the second embodiment of the present invention has a low value of compression set after heat curing, and can be suitably used as a sealing material, an O-ring, a rubber molded body such as a gasket, etc.

[0328] In addition, the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and technical solutions having substantially the same structure and exerting the same technical effects as the technical concept described in the claims of the present invention are all included in the protection scope of the present invention.

Claims

1. An addition-curable fluorosilicone composition, characterized in that: It contains: (A) a vinyl-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1), [Chemical formula 1] In the general formula (1), R 1 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800; (B) a branched organohydrogenpolysiloxane represented by the following formula (3) having three or more silicon-bonded hydrogen atoms in one molecule, wherein the number of hydrogen atoms bonded to silicon atoms in the component (B) is 0.5 to 10 per silicon-bonded vinyl group in the composition, [Chemical formula 2] In the above formula (3), R 4 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms and a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1 is a number of 2≤x1≤4, x2 is an integer of 0≤x2≤20, x3 is an integer of 0≤x3≤20 and satisfies 0≤x2+x3≤20, y1 is an integer of 0≤y1≤30, z1 is an integer of 0≤z1≤10, y2 is an integer of 0≤y2≤30, z2 is an integer of 0≤z2≤10, and z1+z2>0; (C) an addition reaction catalyst in a catalytic amount; and (D) a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (2), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A); [Chemical formula 3] In the above general formula (2), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, and R 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20, The addition-curable fluorosilicone composition is in a liquid state at 23°C.

2. A fluorosilicone rubber, characterized in that: This is a cured product of the addition-curable fluorosilicone composition according to claim 1.

3. A fluorosilicone rubber molded product, characterized in that: It is the molded body of fluorosilicone rubber as claimed in claim 2.

4. An addition-curable fluorosilicone composition, which is a liquid addition-curable fluorosilicone composition, characterized in that: It contains: (A') an alkenyl group-containing organopolysiloxane having a viscosity of 100 to 500,000 mPa·s at 25° C. represented by the following general formula (1A), [Chemical formula 4] In the general formula (1A), R 1 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf are independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group, m is an integer of 0 to 100, n is an integer of 1 to 800, and 5≤m+n≤800; (B') an organohydrogenpolysiloxane having 3 to 5 silicon-bonded hydrogen atoms in one molecule represented by the following general formula (2A), wherein the number of hydrogen atoms bonded to silicon atoms in the component (B') is 0.5 to 10 per silicon-bonded alkenyl group in the composition, [Chemical formula 5] In the above general formula (2A), R 4 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, Rf' is independently selected from a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoropolyether group having 3 to 30 carbon atoms, X is a divalent organic group; x1' is an integer of 3≤x1'≤5, x2' and x3' are integers of 0≤x2'+x3'≤20, y1' is an integer of 0≤y1'≤30, y2' is an integer of 0≤y2'≤30, z1' is an integer of 0≤z1'≤10, z2' is an integer of 0≤z2'≤10, w is 0<w≤10, and x2', x3', y1', y2', z1' and z2' are not 0 at the same time; (C') an addition reaction catalyst in a catalytic amount; and (D') a reinforcing silica filler obtained by surface treatment with an organosilicon compound represented by the following general formula (3A), in an amount of 10 to 60 parts by mass based on 100 parts by mass of the component (A'); [Chemical formula 6] In the above general formula (3A), R 3 are independently selected from an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms, R 2 Independently of each other, the above R 3 or 3,3,3-trifluoropropyl, and at least one R 2 is 3,3,3-trifluoropropyl, p is an integer of 1≤p≤20, The addition-curable fluorosilicone composition is in a liquid state at 23°C.

5. A fluorosilicone rubber, characterized in that: This is a cured product of the addition-curable fluorosilicone composition according to claim 4.

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