JP2023019548A - Addition-curable fluorosilicone composition, silicone rubber, and molded body - Google Patents

Abstract

To provide an addition-curable fluorosilicone composition which gives a cured product satisfactorily adhered to metal and thermoplastic resin and is liquid at 23°C.SOLUTION: An addition-curable fluorosilicone composition is provided, containing: (A) organopolysiloxane represented by general formula (1), in the formula, R1, R4 and R5 each independently are a group 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, x is an integer of 1 to 10, m is an integer of 0 to 100, and n is an integer of 1 to 800, provided that 5≤m+n≤800; (B) organohydrogenpolysiloxane having 2 or more silicon atom-adhered hydrogen atoms in one molecule; (C) an addition reaction catalyst; (D) a reinforcing silica filler surface-treated with an organosilicon compound; and (E) an isocyanuric acid derivative having three trialkoxysilyl groups in one molecule.SELECTED DRAWING: None

Description

The present invention provides an addition-curable fluorosilicone composition that gives a cured product that can adhere well to metals and thermoplastic resins, a fluorosilicone rubber obtained by heat-curing the composition, and a layer of the fluorosilicone rubber and metal. Alternatively, it relates to an integrally molded body comprising a layer of a thermoplastic resin.

Conventionally, liquid addition-curable fluorosilicone rubber compositions have been used for aircraft and automotive rubber parts, printer parts, etc., due to their excellent resistance to gasoline and oil (Patent Document 1). In recent years, it has also been used in mobile parts due to its resistance to sebum. Liquid addition-curable fluorosilicone rubber compositions used in these parts have been desired to be able to adhere to metals and thermoplastic resins. Examples of such methods include insert molding in which a molded metal or thermoplastic resin is placed in a mold, liquid fluorosilicone rubber is injected into the mold, cured by heating, and bonded (Patent Document 2). However, its adhesive function is not clear. Also, there is no example of a molded product obtained by molding, curing, and adhering a liquid addition-curable fluorosilicone rubber adhesive composition by injection molding, compression molding, or injection molding using a mold.

JP 2013-047290 A JP 2013-194113 A

The present invention has been made in view of the above circumstances, and provides an addition-curable fluorosilicone composition which is liquid at 23°C and which provides a cured product which adheres well to metals and thermoplastic resins, and which is obtained by heating and curing the composition. An object of the present invention is to provide a fluorosilicone rubber that can be A further object of the present invention is to provide an integrally molded product formed by adhering a layer of the fluorosilicone rubber and a layer of metal or thermoplastic resin.

The fluorosilicone composition targeted by the present invention contains linear polysiloxane having, as the main chain, a repeating structure of diorganosiloxane units having fluoroalkyl groups, as the main component constituting the matrix of the cured silicone rubber. do. On the other hand, a typical dimethylsilicone composition is based on linear dimethylpolysiloxane whose main chain is composed of repeating dimethylsiloxane units. In this respect, the fluorosilicone composition aimed at by the present invention is essentially different from the dimethylsilicone composition.

The inventors of the present invention have made intensive studies to achieve the above object, and have found that an addition-curable fluorosilicone composition containing an isocyanuric acid derivative having three trialkoxysilyl groups in one molecule as an adhesiveness imparting component. It has been found that the addition-curable fluorosilicone composition it contains gives a cured product that adheres well to metals and thermoplastic resins. Furthermore, the inventors have found that the addition-curable fluorosilicone composition is suitable as a material for injection molding, compression molding and injection molding, and have completed the present invention.

（式中、Ｒ^１、Ｒ^４、及びＲ^５は互いに独立に、炭素数１～８のアルキル基、炭素数６～１２のアリール基、炭素数７～１２のアラルキル基から選ばれる基であり、ｘは１～１０の整数であり、ｍは０～１００の整数であり、ｎは１～８００の整数であり、ただし、５≦ｍ＋ｎ≦８００である）
で示される、２５℃の粘度１００～５００，０００ｍＰａ・ｓを有するオルガノポリシロキサン
（Ｂ）ケイ素原子結合水素原子を１分子中に２個以上有するオルガノハイドロジェンポリシロキサン：（Ａ）成分中のケイ素原子結合ビニル基１個当たり（Ｂ）成分中のケイ素原子結合水素原子の個数比が０．５～１０となる量、
（Ｃ）付加反応触媒：触媒量、
（Ｄ）下記一般式（２）で示される有機ケイ素化合物で表面処理した補強性シリカ充填剤

（上記式（２）中、Ｒ^３は互いに独立に、炭素数１～８のアルキル基、炭素数６～１２のアリール基、炭素数７～１２のアラルキル基から選ばれる基であり、Ｒ^２は、上記Ｒ^３で示される基、又は３,３,３－トリフルオロプロピル基であり、ｐは１≦ｐ≦２０の整数である）
（Ａ）成分１００質量部に対して１０～６０質量部、及び
（Ｅ）１分子中にトリアルコキシシリル基を３個有するイソシアヌル酸誘導体
（Ａ）成分１００質量部に対して０．１～５質量部
を含有することを特徴とする、付加硬化型フルオロシリコーン組成物を提供する。
本発明は好ましくは、液状である上記付加硬化型フルオロシリコーン組成物を提供する。
さらに本発明は該付加硬化型フルオロシリコーン組成物の硬化物であるフルオロシリコーンゴム、及び該シリコーンゴムの成形体、並びに、該シリコーンゴムの層と金属または熱可塑性樹脂から成る層とを有する成形体を提供する。 That is, the present invention provides (A) the following general formula (1)

(wherein R ¹ , R ⁴ and R ⁵ are groups independently selected from alkyl groups having 1 to 8 carbon atoms, aryl groups having 6 to 12 carbon atoms and aralkyl groups having 7 to 12 carbon atoms; , x is an integer from 1 to 10, m is an integer from 0 to 100, and n is an integer from 1 to 800, provided that 5≦m+n≦800)
(B) Organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule: silicon in component (A) an amount such that the number ratio of silicon-bonded hydrogen atoms in component (B) per atom-bonded vinyl group is 0.5 to 10;
(C) addition reaction catalyst: catalytic amount,
(D) Reinforcing silica filler surface-treated with an organosilicon compound represented by the following general formula (2)

(In formula (2) above, R ³ is a group 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 is a group represented by R ³ above, or a 3,3,3-trifluoropropyl group, and p is an integer of 1 ≤ p ≤ 20)
(A) 10 to 60 parts by mass per 100 parts by mass of component, and (E) an isocyanuric acid derivative having three trialkoxysilyl groups in one molecule
Provided is an addition-curable fluorosilicone composition characterized by containing 0.1 to 5 parts by weight of component (A) per 100 parts by weight of component.
The present invention preferably provides the addition-curable fluorosilicone composition described above, which is liquid.
Further, the present invention provides a fluorosilicone rubber which is a cured product of the addition-curable fluorosilicone composition, a molded article of the silicone rubber, and a molded article having a layer of the silicone rubber and a layer of metal or thermoplastic resin. I will provide a.

The addition cure fluorosilicone compositions of the present invention provide self-adhesive fluorosilicone rubbers that adhere well to metals and thermoplastics. It is possible to provide an integrally molded body obtained by bonding a fluorosilicone rubber layer obtained by heating and curing the composition to a metal layer or a thermoplastic resin layer, thereby contributing to improved productivity of adhesive molding and molded products. .

The present invention will be described in more detail below.

（式中、Ｒ^１、Ｒ^４、及びＲ^５は互いに独立に、炭素数１～８のアルキル基、炭素数６～１２のアリール基、炭素数７～１２のアラルキル基から選ばれる基であり、ｘは１～１０の整数であり、ｍは０～１００の整数であり、ｎは１～８００の整数であり、ただし、５≦ｍ＋ｎ≦８００である） (A) Vinyl-containing organopolysiloxane Component (A) is an organopolysiloxane having a viscosity at 25° C. of 100 to 500,000 mPa·s represented by the following general formula (1).

(wherein R ¹ , R ⁴ and R ⁵ are groups independently selected from alkyl groups having 1 to 8 carbon atoms, aryl groups having 6 to 12 carbon atoms and aralkyl groups having 7 to 12 carbon atoms; , x is an integer from 1 to 10, m is an integer from 0 to 100, and n is an integer from 1 to 800, provided that 5≦m+n≦800)

In the above formula (1), R ¹ , R ⁴ and R ⁵ are each independently a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a hexyl group, a cyclohexyl group and the like. an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms such as a phenyl group and tolyl group, and an aralkyl group having 7 to 12 carbon atoms such as a benzyl group. Each of R ¹ , R ⁴ and R ⁵ is preferably an alkyl group having 1 to 8 carbon atoms, particularly preferably a methyl group.

m is an integer of 0-100, preferably 0-50, more preferably 0 or 1-30, even more preferably 0 or 1-20, most preferably 0 or 1-10. n is an integer of 1-800, preferably 5-750, more preferably 10-650, even more preferably 50-650, most preferably 100-650. However, (m+n) is an integer satisfying 5≦m+n≦800, preferably 10≦m+n≦680, more preferably 60≦m+n≦680, and still more preferably 120≦m+n≦680. x is an integer from 1 to 10, preferably from 1 to 3, most preferably x=1.

The viscosity of component (A) at 25° C. is in the range of 100 to 500,000 mPa·s and 300 mPa·s because the physical properties of the cured product are good and the composition is easy to handle. It is preferably in the range of up to 100,000 mPa·s. If the viscosity at 25°C is less than 100 mPa·s, the strength of the cured product will be insufficient. If it exceeds 500,000 mPa·s, the handleability of the composition deteriorates. In the present invention, viscosity is a value measured by a rotational viscometer according to the method described in JIS K 7117-1:1999. (A) The degree of polymerization of the organopolysiloxane is such that the viscosity at 25°C is from 100 to 500,000 mPa·s.

The number of siloxane units having a fluoroalkyl group (that is, the value of n) is preferably 10 with respect to all siloxane units in the molecule (in particular, the total number of bifunctional siloxane units that make up the main chain (that is, n + m). mol % or more, more preferably 20 mol % or more, and particularly preferably 30 to 100 mol %.The upper limit is not particularly limited, and may be 100 mol % or less, 95 mol % or less, 90 mol % or less. or less, or 80 mol % or less, which is preferable because excellent durability against hydrocarbon solvents can be obtained.

(B) Organohydrogenpolysiloxane Component (B) is an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule. The organohydrogenpolysiloxane undergoes a hydrosilylation addition reaction with component (A) and acts as a curing agent (crosslinking agent). There are no particular restrictions on the molecular structure of component (B), and various conventionally produced organohydrogenpolysiloxanes, such as linear, cyclic, branched, and three-dimensional network structures (resinous), can be used. be able to.

The component (B) organohydrogenpolysiloxane has 2 or more (usually 2 to 200), preferably 3 to 100, and particularly preferably 3 to 50 silicon-bonded hydrogen atoms per molecule. (that is, a hydrosilyl group represented by SiH). When the (B) component organohydrogenpolysiloxane has a linear or branched structure, these SiH groups are at the ends of the molecular chain (i.e., diorganohydrogensiloxy groups) and in the middle of the molecular chain (i.e., It may be located on either one or both of the non-terminally located bifunctional organohydrogensiloxane units or trifunctional hydrogensilsesquioxane units).

A monovalent organic group bonded to a silicon atom other than a hydrogen atom bonded to a silicon atom is a C1-10, preferably C1-8, unsubstituted or substituted aliphatically unsaturated group such as a vinyl group. A monovalent hydrocarbon group containing no bond can be exemplified. For example, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group and decyl group, Aryl groups such as phenyl group, tolyl group, xylyl group and naphthyl group; aralkyl groups such as benzyl group, phenylethyl group and phenylpropyl group; substituted with a halogen atom, such as a fluoroalkyl group such as a trifluoropropyl group. Preferred are fluoroalkyl groups such as methyl group and trifluoropropyl group. The number (or degree of polymerization) of silicon atoms in one molecule of component (B) is preferably 2 to 300, more preferably 3 to 200, still more preferably 4 to 150.

Component (B) is preferably liquid at room temperature (25°C). The viscosity of component (B) at 25° C. is preferably 0.1 to 1,000 mPa·s, more preferably 0.5 to 500 mPa·s, still more preferably 1 to 200 mPa·s. If the viscosity of the component (B) is too low or too high, the workability of the composition may deteriorate.

Examples of (B) organohydrogenpolysiloxane include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, tris(hydrogendimethylsiloxy)methylsilane, tris (Hydrogendimethylsiloxy)phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane/dimethylsiloxane cyclic copolymer, both ends trimethylsiloxy group-blocked methylhydrogenpolysiloxane, both ends trimethylsiloxy group-blocked dimethylsiloxane/methyl Hydrogensiloxane copolymer, both terminal trimethylsiloxy group-blocked methylhydrogensiloxane/trifluoropropylmethylsiloxane copolymer, both terminal dimethylhydrogensiloxy group-blocked dimethylpolysiloxane, both terminal dimethylhydrogensiloxy group-blocked dimethylsiloxane/ Methylhydrogensiloxane copolymer, both ends dimethylhydrogensiloxy group-blocked methylhydrogensiloxane/trifluoropropylmethylsiloxane copolymer, both ends dimethylhydrogensiloxy group-blocked trifluoropropylmethylpolysiloxane, both ends dimethylhydrogen Siloxy group-blocked dimethylsiloxane/methylhydrogensiloxane copolymer, both ends trimethylsiloxy group-blocked methylhydrogensiloxane/diphenylsiloxane copolymer, both ends trimethylsiloxy group-blocked methylhydrogensiloxane/diphenylsiloxane/dimethylsiloxane copolymer , both terminal trimethylsiloxy group-blocked methylhydrogensiloxane/methylphenylsiloxane/dimethylsiloxane copolymer, both terminal dimethylhydrogensiloxy group-blocked methylhydrogensiloxane/dimethylsiloxane/diphenylsiloxane copolymer, both terminal dimethylhydrogensiloxy Group-blocked methylhydrogensiloxane/dimethylsiloxane/methylphenylsiloxane copolymer, copolymer composed of (CH ₃ ) ₂ HSiO _1/2 units, (CH ₃ ) ₃ SiO _1/2 units and SiO _4/2 units , (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 units, (CH ₃ ) ₂ HSiO _1/2 units, SiO _4/2 units and (C ₆ H ₅ )SiO _3/ A copolymer consisting of _two units, , and the above-exemplified compounds in which part or all of the methyl group is substituted with another alkyl group, phenyl group, trifluoropropyl group, or the like. Organohydrogenpolysiloxane may be used alone or in combination of two or more.

式（６）中、Ｒ^１’は互いに独立に、水素原子、炭素数１～８のアルキル基、炭素数６～１２のアリール基、炭素数７～１２のアラルキル基から選ばれる基であり、上記Ｒ^１のために例示した基が挙げられる。但し、Ｒ^１’のうち少なくとも２つ、好ましくは３～１００個、より好ましくは３～５０個は水素原子である。ｘ’は１～１０の整数であり、好ましくは１～３であり、最も好ましくはｘ’＝１である。ｋは２～２００の整数、好ましくは３～１００の整数、より好ましくは５～５０の整数であり、ｑは０～２００の整数であり、好ましくは１～１００の整数であり、より好ましくは２～１００の整数である。ｋ＋ｑは２～３００であり、より好ましくは３～２００、更に好ましくは４～１５０であるのがよい。 Component (B) is more preferably represented by the following formula (6).

In formula (6), R ^1′ is a group independently selected from a hydrogen atom, 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; The groups exemplified for R ¹ above can be mentioned. However, at least two, preferably 3 to 100, more preferably 3 to 50, R ^1′ are hydrogen atoms. x' is an integer from 1 to 10, preferably from 1 to 3, most preferably x'=1. k is an integer of 2 to 200, preferably an integer of 3 to 100, more preferably an integer of 5 to 50; q is an integer of 0 to 200, preferably an integer of 1 to 100, more preferably An integer from 2 to 100. k+q is 2-300, more preferably 3-200, still more preferably 4-150.

The amount of component (B) is such that the number ratio of silicon-bonded hydrogen atoms in component (B) to one silicon-bonded vinyl group in component (A) is 0.5 to 10, preferably 1 to It is an amount that falls within the range of five. If the amount of component (B) is less than the above lower limit, the obtained composition will not be sufficiently cured. On the other hand, if the amount of component (B) exceeds the above upper limit, the heat resistance of the resulting silicone rubber will be extremely poor. When a vinyl group-containing organosiloxane other than component (A), which will be described later, is included, the ratio of the number of silicon-bonded hydrogen atoms in component (B) to the number of vinyl groups bonded to silicon atoms in the composition is It is sufficient if the above range is satisfied.

(C) Addition reaction catalyst Component (C) is an addition reaction catalyst. Component (C) may be any catalyst that promotes the addition reaction between the vinyl groups in component (A) and the silicon-bonded hydrogen atoms in component (B). Generally, a platinum group metal-based catalyst can be suitably used. For example, platinum, palladium, rhodium, etc., chloroplatinic acid, alcohol-modified chloroplatinic acid, coordination compounds of chloroplatinic acid and olefins, vinylsiloxane or acetylene compounds, tetrakis (triphenylphosphine) palladium, chlorotris (triphenylphosphine) ) platinum group metals such as rhodium or compounds thereof, and platinum-based compounds are particularly preferred. (C) component may be used individually by 1 type, or may use 2 or more types together.

The amount of component (C) to be blended may be an effective amount as a catalyst. , usually in the range of 0.5 to 1,000 ppm, preferably in the range of 1 to 500 ppm, more preferably in the range of 10 to 100 ppm. When this range is satisfied, the reaction rate of the addition reaction becomes appropriate and the heat resistance of the cured product becomes good.

上記式（２）中、Ｒ^３は互いに独立に、炭素数１～８のアルキル基、炭素数６～１２のアリール基、炭素数７～１２のアラルキル基から選ばれる基であり、例えば上記Ｒ^１のために記載した例示が挙げられる。好ましくはメチル基である。Ｒ^２は、上記Ｒ^３で示される基、又は３，３，３－トリフルオロプロピル基である。好ましくは、Ｒ^２は、メチル基又は３，３，３－トリフルオロプロピル基であり、少なくとも１のＲ^２は３，３，３－トリフルオロプロピル基であるのがよい。ｐは、１～２０の整数であり、好ましくは３～９の整数である。
本発明において該補強性シリカ充填剤は、得られるシリコーンゴムに十分な強度を与えるために必須である。 (D) Reinforcing Silica Filler Component (D) is reinforcing silica surface-treated with a linear organosilicon compound having silanol groups at both ends of the molecular chain represented by the following formula (2).

In the above formula (2), R ³ is a group 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. The examples described for ¹ can be mentioned. A methyl group is preferred. R ² is a group represented by R ³ above or a 3,3,3-trifluoropropyl group. Preferably, R ² is a methyl group or a 3,3,3-trifluoropropyl group and at least one R ² is a 3,3,3-trifluoropropyl group. p is an integer of 1-20, preferably an integer of 3-9.
In the present invention, the reinforcing silica filler is essential for imparting sufficient strength to the resulting silicone rubber.

By containing a reinforcing silica filler surface-treated with a linear organosilicon compound in which both ends of the molecular chain are blocked with silanol groups, the viscosity of the present composition and the tackiness of the rubber molded article are reduced. can be done.

As the reinforcing silica filler, those conventionally used in silicone rubber compositions can be used, and precipitated silica (wet silica), fumed silica (dry silica), pyrogenic silica and the like are suitable. Fumed silica is particularly preferred.

Component (D) may be surface-untreated silica previously surface-treated with the organosilicon compound of formula (2) above. Alternatively, surface-untreated silica and the polysiloxane component of the present invention (that is, component (A)) are kneaded, the organosilicon compound of the above formula (2) is added, and preferably in the presence of a small amount of water, Heat mixing may be used to surface treat in the mixture. In the present invention, the silica to be surface-treated with the organosilicon compound of formula (2) above may be dry silica (eg, Aerosil R-974, etc.) previously surface-treated with dimethyldichlorosilane or the like. It is preferable to further treat the surface of the dry silica surface-treated with dimethyldichlorosilane or the like with the organosilicon compound of formula (2).

When silica is surface-treated with the organosilicon compound of formula (2), the treatment amount is 1 to 1 to 40 parts by mass of silica before surface treatment with the organosilicon compound of formula (2). 30 parts by mass, preferably about 2 to 20 parts by mass.

The BET specific surface area of silica before surface treatment with the organosilicon compound of formula (2) is 50 m ² /g or more, preferably 100 to 400 ^{m 2} /g, more preferably 150 to 350 m ² /g. . If the specific surface area is less than 50 m ² /g, not only is sufficient strength not obtained, but also the appearance of the rubber molded product may be poor. If it is more than 400 m ² /g, it may become difficult to blend. The specific surface area of the silica after the surface treatment as determined by the BET method may also be within the above range.

Component (D) is added in an amount of 10 to 60 parts by mass, preferably 15 to 55 parts by mass, per 100 parts by mass of component (A). If the amount is less than the above lower limit, the resulting silicone rubber will not have sufficient rubber strength, and if it exceeds the above upper limit, it will be difficult to incorporate it into the composition.

(E) Adhesion imparting agent Component (E) is an isocyanuric acid derivative having three trialkoxy groups in one molecule. The (E) component is an adhesion imparting agent. By containing component (E), the cured product obtained from the addition-curable fluorosilicone composition of the present invention can have self-adhesive properties. More specifically, the component (E) of the present invention is an isocyanuric acid derivative having three trialkoxysilyl groups such as a trimethoxysilyl group and a triethoxysilyl group in one molecule. More preferred are isocyanuric acid derivatives having three trialkoxysilyl-substituted alkyl groups. Examples of alkyl groups such as the above trimethoxysilyl-substituted alkyl groups include ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group having 2 to 10 carbon atoms, Examples include an octyl group, and among these, a propyl group is preferred. By blending the component (E), the resulting composition can have excellent adhesion to metals and thermoplastic resins.

（Ｒ^６は、互いに独立に、炭素数１～３のアルキル基である）
トリアルコキシ基は、トリメトキシシリル基又はトリエトキシシリル基が挙げられる。 Component (E) is preferably an isocyanuric acid derivative represented by the following formula (3) and having three trialkoxysilyl-substituted propyl groups in one molecule.

(R ⁶ is each independently an alkyl group having 1 to 3 carbon atoms)
A trialkoxy group includes a trimethoxysilyl group or a triethoxysilyl group.

The amount of component (E) is 0.1 to 5 parts by mass, preferably 0.2 to 3.5 parts by mass, more preferably 0.3 to 3.0 parts by mass, per 100 parts by mass of component (A). It is in the range of parts by mass. If the amount of component (E) is less than the above lower limit, the resulting cured product cannot have good adhesion to metals and thermoplastic resins. On the other hand, when the above upper limit is exceeded, the heat resistance of the cured product may be remarkably lowered.

The addition-curable fluorosilicone composition of the present invention may optionally contain other components in addition to components (A) to (E) as long as they do not impair the appearance of the molded rubber article. For example, carbon black, conductive zinc oxide, conductive agents such as metal powder, hydrosilylation reaction control agents such as nitrogen-containing compounds, acetylene compounds, phosphorus compounds, nitrile compounds, carboxylates, tin compounds, mercury compounds, sulfur compounds, oxidation Heat resistance imparting agents such as iron and cerium oxide, compression set improvers such as triazole compounds and benzotriazole derivatives, internal release agents such as dimethyl silicone oil, adhesion imparting agents other than the above component (E), and thixotropic Sex imparting agents and the like can be mentioned.

Further, for example, a dimethylpolysiloxane containing vinyl groups at both ends and having no fluoroalkyl groups, other than the above component (A), can be included. More specifically, it is an organopolysiloxane having an average degree of polymerization of 1,500 or less and which is liquid at room temperature and has vinyl groups at both ends. The average degree of polymerization is preferably 1,500 or less, usually 100 to 1,500, preferably 150 to 1,100. The viscosity at 25° C. measured by a rotational viscometer according to JIS K 6249:2003 is 1,000 to 100,000 mPa·s, preferably 5,000 to 100,000 mPa·s. The amount of the dimethylpolysiloxane compounded is 1 to 20 parts by weight, preferably 1 to 15 parts by weight, per 100 parts by weight of component (A).

The compositions of the present invention may also contain vinyl-containing MQ resins. More specifically, it is an MQ resin having a vinyl group content of 0.01 to 5 mmol/g, preferably 0.1 to 1 mmol/g. The molar ratio of M units to Q units (M units/Q units) should be between 0.5 and 1.5, preferably between 0.7 and 1.2. The molecular weight of the vinyl group-containing MQ resin is preferably 2,000 to 8,000, particularly 4,000 to 6,000, as determined by gel permeation chromatography (GPC) using polystyrene as a standard material. , which is normally solid at room temperature. The amount of MQ resin compounded is 1 to 20 parts by mass, preferably 1 to 15 parts by mass, per 100 parts by mass of component (A).

The addition-curable fluorosilicone composition of the present invention is prepared by mixing the above components (A) to (E) and, if necessary, each optional component, using a conventional mixing agitator or kneader such as a kneader or planetary mixer. It can be prepared by mixing uniformly with

The composition of the present invention is preferably liquid at 23 ° C., and from the viewpoint of workability, etc., it is preferable that the viscosity at a shear rate of 0.9 s ^-1 at 23 ° C. is 8,000 Pa s or less, and more It is preferably 100 to 7,000 Pa·s, more preferably 500 to 6,500 Pa·s, particularly preferably 1,600 to 6,000 Pa·s, particularly preferably 2,000 to 6,000 Pa·s. If the viscosity exceeds 8,000 Pa·s, it takes a long time to supply the material during injection, compression, and injection molding, resulting in a significant drop in productivity. In the present invention, the measurement of the viscosity under the shear rate was performed using a precision rotary viscometer (manufactured by Thermo Fisher Scientific).

The addition-curable fluorosilicone composition of the present invention can also be of a two-part type. In this case, each component may be appropriately divided so that component (B) as a cross-linking agent and component (C) as an addition reaction catalyst are not mixed in the same composition (solution A or solution B). Two liquids consisting of liquid A containing components (A), (C) and (D) and liquid B containing components (A), (B), (D) and (E) It can be a composition of the type and is preferably prepared so that it can be mixed in equal mass or equal volume.

The addition-curable fluorosilicone composition of the present invention can be applied to various molding methods such as injection molding, compression molding, and injection molding. Available. The present invention further provides a molded article, preferably an integrally molded article, having a layer of fluorosilicone rubber, which is a cured product of an addition-curable fluorosilicone composition, and a layer of metal or thermoplastic resin. Methods for molding fluorosilicone rubber by injection molding, compression molding, or injection molding are described in detail below. In the present invention, an integrally molded body is, for example, a body in which resin parts or metal parts are inserted into a mold and filled with silicone rubber so as to be tightly adhered and integrated.

In the case of injection molding, addition-curable fluorosilicone compositions are divided into two types, A and B. The material divided into two liquids is mixed with equal amounts of each liquid A and B, injected into a metal mold, heated in a constant temperature bath and cured to form a silicone rubber. In the case of compression molding, a metal mold is installed in a compressor such as a press, and equal amounts of the above liquids A and B are mixed in the same manner as injection molding, injected into the mold, heated and cured to form silicone rubber. is molded. In the case of injection molding, each A liquid and B liquid are supplied to a metering device from a material supply pump. From the metering device, the A liquid and the B liquid are combined at an equal ratio through the material supply line. Materials are mixed in the screw part and the cylinder part of the molding machine body. After that, it is injected into a mold, heated in the mold and cured to form a silicone rubber.

The curing conditions for the addition-curable fluorosilicone composition may be the same as those for known liquid addition reaction-curable silicone compositions. For example, the curing temperature is 80 to 200° C., particularly 100 to 180° C., and curing and molding can be performed by heating for 3 to 60 minutes, particularly 5 to 30 minutes.

Fluorosilicone rubber molded articles obtained by heat-curing the addition-curable fluorosilicone composition of the present invention are excellent in gasoline resistance and oil resistance. From the viewpoint of sebum resistance, it can also be suitably used for mobile parts.

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

The viscosity of component (A) was measured at 25° C. with a BH-type rotational viscometer (rotor No. 7, rotation speed 10 rpm). The viscosity of component (B) was measured at 25° C. with a BL-type rotational viscometer (rotor No. 2, rotation speed 60 rpm).

The viscosity measurement of the composition was performed by the following method.
The viscosity of the composition was measured at a shear rate of 0.9 s ⁻¹ at 23° C. using a precision rotary viscometer (manufactured by Thermo Fisher Scientific) using a cone and plate measuring jig.

The hardness, tensile strength, elongation at break, and tear strength (angle) of the cured product were measured by the following methods.
The composition was subjected to primary vulcanization by press curing at 150°C/10 minutes. The hardness, tensile strength, elongation at break, and tear strength (angle) of the cured product were measured according to JIS K 6249:2003.

The shear adhesive strength of the cured product to various substrates was measured by the following method.
(1) The composition was filled between two plates of stainless steel (SUS) having dimensions of 25 mm in width, 100 mm in length, and 0.3 mm in thickness, and cured by heating in a constant temperature bath at 120°C for 30 minutes. A test piece having a rubber layer adhesion area of 25 mm×10 mm and a rubber layer thickness of 2 mm was prepared.
(2) The composition is filled between two flat aluminum (Al) sheets with dimensions of 25 mm in width, 100 mm in length and 1 mm in thickness, and cured by heating in a constant temperature bath at 120°C for 30 minutes to bond the rubber layer. A test piece having an area of 25 mm×10 mm and a rubber layer thickness of 2 mm was prepared.
(3) The composition is filled between two sheets of flat polyamide 6 resin (PA6 resin) having a width of 25 mm, a length of 100 mm and a thickness of 2 mm, and cured by heating in a constant temperature bath at 120 ° C. for 30 minutes to obtain a rubber. A test specimen was prepared with a layer adhesion area of 25 mm×10 mm and a rubber layer thickness of 2 mm.
For each of the above test pieces, a horizontal tensile stress was applied to the bonding surface to measure the shear bond strength.

で示される両末端がジメチルビニルシロキシ基で封鎖された２５℃の粘度が８０．８Ｐａ・ｓであるトリフルオロプロピルメチルポリシロキサン（ビニル基含有量４．５×１０^－５ｍｏｌ／ｇ）
（Ｄ）成分：ＢＥＴ法による比表面積が２００ｍ^２／ｇであるヒュームドシリカ（日本アエロジル社製、アエロジルＲ－９７４）と、
下記式（２）で示されるシラノール化合物

（Ｂ）架橋剤：下記式（３）で示されるメチルハイドロジェンポリシロキサン（粘度０．０６Ｐａ・ｓ、ＳｉＨ基量０．００４７ｍｏｌ／ｇ）

（Ｃ）白金触媒（Ｐｔ濃度 ０．５質量％）
（Ｅ）接着付与剤：下記式（５）で表される化合物

（Ｆ）２５℃での粘度が約５Ｐａ・ｓであり、平均重合度が約４４８の両末端ジメチルビニルシロキシ基封鎖ジメチルポリシロキサン（１分子当たりのビニル基数：２個、ビニル基含有量：０．０６０ミリモル／ｇ）
（Ｇ）（ＣＨ_３）_３ＳｉＯ_１／２（Ｍ）単位、（ＣＨ_２＝ＣＨ）（ＣＨ_３）_２ＳｉＯ_１／２（Ｍ）単位、及びＳｉＯ_４／２（Ｑ）単位からなる共重合体（１分子当たりのビニル基数：４．０個、ビニル基含有量は０．８４ミリモル／ｇ、１分子中のＭ単位のＱ単位に対するモル比（Ｍ単位／Ｑ単位）は０．８５）
反応制御剤：エチニルシクロヘキサノール
圧縮永久歪向上剤：下記式（４）で示されるベンゾトリアゾールシラン

耐熱性付与剤：酸化セリウム Each component used in the following examples and comparative examples is as follows (A) component: the following formula (1)

A trifluoropropylmethylpolysiloxane having a viscosity of 80.8 Pa s at 25° C. (vinyl group content: 4.5×10 ⁻⁵ mol/g) having both ends blocked with dimethylvinylsiloxy groups represented by
(D) component: fumed silica (Aerosil R-974, manufactured by Nippon Aerosil Co., Ltd.) having a specific surface area of 200 m ² /g by the BET method;
A silanol compound represented by the following formula (2)

(B) Cross-linking agent: methylhydrogenpolysiloxane represented by the following formula (3) (viscosity 0.06 Pa s, SiH group content 0.0047 mol/g)

(C) platinum catalyst (Pt concentration 0.5% by mass)
(E) Tackifier: a compound represented by the following formula (5)

(F) Dimethylpolysiloxane having a viscosity at 25° C. of about 5 Pa·s and an average degree of polymerization of about 448, dimethylvinylsiloxy group-blocked at both ends (number of vinyl groups per molecule: 2, vinyl group content: 0 .060 mmol/g)
(G) a copolymer consisting of (CH ₃ ) ₃ SiO _1/2 (M) units, (CH ₂ ═CH)(CH ₃ ) ₂ SiO _1/2 (M) units, and SiO _4/2 (Q) units; coalescence (number of vinyl groups per molecule: 4.0, vinyl group content is 0.84 mmol/g, molar ratio of M units to Q units in one molecule (M units/Q units) is 0.85)
Reaction control agent: ethynylcyclohexanol Compression set improver: benzotriazole silane represented by the following formula (4)

Heat resistance imparting agent: Cerium oxide

[Example 1]
(A) 55 parts by mass of trifluoropropylmethylpolysiloxane (vinyl group content: 4.5×10 ⁻⁵ mol/g) represented by formula (1) above, 40 parts by mass of fumed silica above, formula (2) above: After mixing 6.6 parts by mass of a silanol compound represented by, 0.55 parts by mass of water, and 0.3 parts by mass of 1,3-divinyl-1,1,3,3-tetramethyldisilazane at room temperature for 30 minutes, The temperature was raised to 160° C. and stirring was continued for 3 hours. Further, 65 parts by mass of trifluoropropylmethylpolysiloxane represented by the above formula (1) was added, and after mixing for 30 minutes, a silicone rubber base was obtained.
320 parts by mass of the above silicone rubber base, 17 parts by mass of trifluoropropylmethylpolysiloxane represented by the above formula (1) (the amount of component (D) per 100 parts by mass of component (A) is 31.1 parts by mass. ), (F) 2.5 parts by mass of dimethylpolysiloxane endblocked with dimethylvinylsiloxy groups at both ends, (G) 2.5 parts by mass of a copolymer comprising MQ units, and (B) the above formula (3) 8.3 parts by mass of methylhydrogenpolysiloxane shown (number ratio of SiH groups in component (B) to number of silicon-bonded vinyl groups in component (B) [SiH/SiVi] = 2.3, above (A ) The number ratio [SiH/SiVi] of SiH groups in component (B) to SiVi in component (B) is 3.6), the reaction control agent 0.08 parts by mass, (C) platinum catalyst (Pt concentration 0.5% by mass ) 0.4 parts by mass, 0.015 parts by mass of the compression set improver, 0.57 parts by mass of the heat resistance imparting agent, and (E) 1.7 parts by mass of the compound represented by the above formula (5) ( Component (E) was added in an amount of 1.4 parts by mass to 100 parts by mass of Component (A).
The viscosity of the addition-curable fluorosilicone composition 1 obtained was measured by the method described above. In addition, the composition was cured by the above method, and the hardness, tensile strength, elongation at break, tear strength (angle), and shear adhesive strength to various substrates of the cured product were measured. Table 1 shows the results.

[Example 2]
Example 1 was repeated except that the amount of the tackifier (E) was changed to 3.4 parts by mass (the amount of component (E) was 2.8 parts by mass with respect to 100 parts by mass of component A). An addition-curable fluorosilicone composition 2, which is liquid at 0° C., was prepared.
The viscosity of the obtained addition-curable fluorosilicone composition 2 was measured by the method described above. In addition, the composition was cured by the above method, and the hardness, tensile strength, elongation at break, tear strength (angle), and shear adhesive strength to various substrates of the cured product were measured. Table 1 shows the results.

[Comparative Example 1]
Addition curable fluorosilicone composition 3 liquid at 23° C. was prepared by repeating Example 1 except that (E) the tackifier was not added.
The viscosity of the resulting addition-curable fluorosilicone composition 3 was measured by the method described above. In addition, the composition was cured by the above method, and the hardness, tensile strength, elongation at break, tear strength (angle), and shear adhesive strength to various substrates of the cured product were measured. Table 1 shows the results.

[Comparative Example 2]
In Example 1, when the tackifier (E) was blended in an amount of more than 5 parts by weight per 100 parts by weight of component (A), the resulting composition had high viscosity and poor handleability.

As shown in Table 1 above, the silicone composition of the present invention exhibits excellent adhesion to all aluminum plates, stainless steel plates, and polyamide resins due to the inclusion of component (E).
Thus, the addition-curable fluorosilicone compositions of the present invention provide self-adhesive fluorosilicone rubbers that adhere well to metals and thermoplastic resins.

Claims (8)

(A) the following general formula (1)

(wherein R ¹ , R ⁴ and R ⁵ are groups independently selected from alkyl groups having 1 to 8 carbon atoms, aryl groups having 6 to 12 carbon atoms and aralkyl groups having 7 to 12 carbon atoms; , x is an integer from 1 to 10, m is an integer from 0 to 100, and n is an integer from 1 to 800, provided that 5≦m+n≦800)
(B) Organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule: silicon in component (A) an amount such that the number ratio of silicon-bonded hydrogen atoms in component (B) per atom-bonded vinyl group is 0.5 to 10;
(C) addition reaction catalyst: catalytic amount,
(D) Reinforcing silica filler surface-treated with an organosilicon compound represented by the following general formula (2)

(In formula (2) above, R ³ is a group 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 is a group represented by R ³ above, or a 3,3,3-trifluoropropyl group, and p is an integer of 1 ≤ p ≤ 20)
(A) 10 to 60 parts by mass per 100 parts by mass of component, and (E) an isocyanuric acid derivative having three trialkoxysilyl groups in one molecule
An addition-curable fluorosilicone composition characterized by containing 0.1 to 5 parts by weight per 100 parts by weight of component (A). The addition-curable fluorosilicone composition of Claim 1, wherein component (E) is represented by the following formula (3):

(R ⁵ are each independently an alkyl group having 1 to 3 carbon atoms). 3. The addition-curable fluorosilicone composition according to claim 1, wherein in component (D), ^R2 is a methyl group or a 3,3,3-trifluoropropyl group. The addition-curable fluorosilicone composition according to any one of claims 1 to 3, wherein x in formula (1) is 1. The addition-curable fluorosilicone composition according to any one of claims 1 to 4, which is liquid at 23°C. The addition-curable fluorosilicone composition according to any one of claims 1 to 5, which is for injection molding, compression molding or injection molding. A fluorosilicone rubber which is a cured product of the addition-curable fluorosilicone composition according to any one of claims 1 to 5. A molded article comprising a layer comprising the fluorosilicone rubber according to claim 7 and a layer comprising a metal or a thermoplastic resin.