Heat-resistant silicone oil composition

Abstract

Provided is a silicone oil composition which does not cause separation, precipitation or the like even when stored for a long period of time and has excellent heat resistance. The heat-resistant silicone oil composition comprises: (A) 100 parts by mass of an organopolysiloxane having a kinematic viscosity of 50-5000 mm2 / s at 25 DEG C as measured by a cannon-Vinck viscometer in accordance with the method described in JISZ 8803: 2011, and (B) 100 parts by mass of an organopolysiloxane having a kinematic viscosity of 50-5000 mm2 / s at 25 DEG C as measured by the method described in JISZ 8803: 2011; and (B) 10-100 parts by mass of a (poly) thiophene-(poly) siloxane block copolymer comprising a structure represented by formula (1) [Chemical Formula 1] # imgabs0 # [in the formula, R1 independently represents a hydrogen atom or a hydrocarbon group having 1-10 carbon atoms, R2 independently represents a hydrocarbon group having 1-10 carbon atoms, a is 1-3, b is 2-200, and c is 1-40. ]

Description

Technical Field

[0001] The invention relates to a heat-resistant silicone oil composition. Background Art

[0002] In the past, silicone oils were used for applications such as lubricating oils and hydraulic oils. In particular, for applications requiring heat resistance, phenyl silicone oils having phenyl groups or 2-phenylpropyl groups were often used. However, even these phenyl silicone oils do not have sufficient heat resistance and produce aromatic hydrocarbons during thermal decomposition, which poses problems both in terms of performance and safety.

[0003] In addition, methods of adding various heat resistance improvers to silicone oil have been studied. Heat resistance improvers used in hydrocarbon lubricating oils such as metal soaps and aromatic amines are also used in silicone oil. However, these heat resistance improvers are not only insufficiently compatible with silicone oil, but also not heat resistance improvers that can satisfy the effect of improving heat resistance.

[0004] Patent Document 1 discloses an attempt to improve heat resistance by blending fullerene into silicone oil. However, fullerene is solid and its compatibility with silicone oil is not sufficient, and there are still problems such as separation and precipitation during long-term storage.

[0005] As described above, research on a silicone oil composition having excellent heat resistance that does not cause separation, precipitation, etc. even during long-term storage has been sought.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2005-206761 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] Therefore, an object of the present invention is to provide a silicone oil composition having excellent heat resistance and which does not cause separation, precipitation, etc. even during long-term storage.

[0011] Methods used to solve problems

[0012] In order to solve the above-mentioned problems, the present inventors have repeatedly conducted in-depth studies and found that a silicone oil composition comprising silicone oil and a heat-resistant (poly)thiophene-(poly)siloxane block copolymer does not cause separation, precipitation, etc. even when stored for a long time, and has excellent heat resistance, and can achieve the above-mentioned purpose, thereby completing the present invention.

[0013] The present invention provides the following heat-resistant silicone oil composition.

[0014] [1] A heat-resistant silicone oil composition comprising:

[0015] (A) The kinematic viscosity at 25°C measured by a Cannon-Fenske viscometer according to the method described in JIS Z8803:2011 is 50 to 5000 mm 2 / s of organopolysiloxane: 100 parts by mass; and

[0016] (B) (poly)thiophene-(poly)siloxane block copolymer having a structure represented by the following formula (1): 10 to 100 parts by mass.

[0017] [Chemical formula 1]

[0018]

[0019] [In the formula, R 1 are independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R 2 They are independently a hydrocarbon group having 1 to 10 carbon atoms, a is 1 to 3, b is 2 to 200, and c is 1 to 40.]

[0020] [2] The heat-resistant silicone oil composition according to [1], wherein

[0021] (A) Component is dimethyl polysiloxane.

[0022] [3] The heat-resistant silicone oil composition according to [1] or [2], wherein

[0023] The component (B) is a (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (2).

[0024] [Chemical formula 2]

[0025]

[0026] [In the formula, R 1 are independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R 2 Each of them is independently a hydrocarbon group having 1 to 10 carbon atoms, each of a is independently 1 to 3, b is 2 to 200, and c is 1 to 40.]

[0027] Effects of the Invention

[0028] According to the present invention, a silicone oil composition can be provided which does not cause separation or sedimentation even during long-term storage and has excellent heat resistance even under high temperature conditions of 300° C. or higher. The silicone oil composition of the present invention is useful for applications such as heat transfer agents, mold release agents, and resin modifiers. DETAILED DESCRIPTION

[0029] Hereinafter, the present invention will be described in detail.

[0030] [(A) Organopolysiloxane]

[0031] The organopolysiloxane as the component (A) of the present invention is characterized in that the kinematic viscosity at 25° C. measured by a Cannon-Fenske viscometer according to the method described in JIS Z8803:2011 is 50 to 5000 mm 2 / s, and preferably 100 to 1000 mm 2 / s, more preferably 100 to 500 mm 2 / s. If the kinematic viscosity is less than 50mm 2 / s, the component (A) itself may volatilize easily under high temperature conditions, or the desired properties as silicone oil may not be obtained. 2 / s, the compatibility of the component (A) and the component (B) described later may be deteriorated, or the handling property may also be deteriorated.

[0032] The molecular structure of the organopolysiloxane may be linear or partially branched, but is preferably a linear organopolysiloxane represented by the following formula (3).

[0033] [Chemical formula 3]

[0034]

[0035] (In the formula, R is independently a group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms, and n is a number from 30 to 700.)

[0036] Among them, R is independently a group selected from an alkyl group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, preferably 6 to 8 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms, preferably 7 to 8 carbon atoms. Examples of alkyl groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl, decyl, cyclopentyl, and cyclohexyl. Examples of aryl groups include phenyl and tolyl. Examples of aralkyl groups include benzyl and 2-phenylpropyl. Among them, alkyl groups are preferred, and methyl groups are particularly preferred. R may be the same or different, but preferably 90% or more of all R are methyl groups, and more preferably all R are methyl groups.

[0037] In addition, the component (A) of the present invention is intended to reduce the volatile components under high temperature conditions, and a component with a reduced content of low molecular weight siloxanes, such as cyclic siloxanes, may also be used. Specifically, the total amount of cyclic polysiloxanes (D3-D20) having 3 to 20 silicon atoms is preferably 3000 ppm or less, more preferably 100 to 2000 ppm. If the total amount of the cyclic polysiloxane is within this range, the pollution of the surrounding environment and the occurrence of faults such as electrical contact failures can be suppressed.

[0038] [(B) (Poly)thiophene-(Poly)siloxane block copolymer]

[0039] The (poly)thiophene-(poly)siloxane block copolymer as the (B) component of the present invention is a (poly)thiophene-(poly)siloxane block copolymer having a structure represented by the following formula (1), preferably a (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (2). The (B) component is a component that imparts heat resistance to the heat-resistant silicone oil composition of the present invention.

[0040] [Chemical formula 4]

[0041]

[0042] In formula (1) and formula (2), R 1 They are independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. Examples of the hydrocarbon group having 1 to 10 carbon atoms include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; aryl groups such as phenyl and tolyl; and alkenyl groups such as vinyl and allyl. Among them, a hydrogen atom and an alkyl group are preferred, and a hydrogen atom is more preferred.

[0043] In formula (1) and formula (2), R 2 Each of them is independently a hydrocarbon group having 1 to 10 carbon atoms. Examples of the hydrocarbon group having 1 to 10 carbon atoms include alkyl groups such as methyl, ethyl, propyl, butyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; aryl groups such as phenyl and tolyl; and alkenyl groups such as vinyl and allyl. Among them, an alkyl group is preferred, and a methyl group is more preferred.

[0044] In formula (1) and formula (2), a is independently 1 to 3, preferably 1 to 2, and more preferably 1. In formula (1) and (2), b is 2 to 200, preferably 4 to 200, and more preferably 4 to 100. In formula (1) and (2), c is 1 to 40, preferably 1 to 30, and more preferably 1 to 20. Within this range, the compatibility of the component (B) with the organopolysiloxane of the component (A) is excellent, and the composition of the present invention is a composition excellent in heat resistance.

[0045] In the present invention, the bonding form of the (poly)thiophene-(poly)siloxane unit (Formula (1)) is linear or cyclic.

[0046] In addition, the component (B) of the present invention is intended to reduce the volatile components under high temperature conditions, and a component with a reduced content of low molecular weight siloxanes, such as cyclic siloxanes, may also be used. Specifically, the total amount of cyclic polysiloxanes (D3-D20) having 3 to 20 silicon atoms is preferably 3000 ppm or less, more preferably 100 to 2000 ppm. If the total amount of the cyclic polysiloxane is within this range, the pollution of the surrounding environment and the occurrence of faults such as electrical contact failures can be suppressed.

[0047] The amount of component (B) is 10 to 100 parts by mass, preferably 15 to 50 parts by mass, relative to 100 parts by mass of the organopolysiloxane of component (A). If the amount of component (B) is less than 10 parts by mass, sufficient heat resistance cannot be imparted to the composition of the present invention. If the amount of component (B) exceeds 100 parts by mass, the compatibility between component (B) and component (A) may deteriorate, or the inherent properties of the silicone oil of component (A) may be impaired.

[0048] The total content of the components (A) and (B) in the composition of the present invention is preferably 90 to 100%, more preferably 95 to 100%, and even more preferably 98 to 100%.

[0049] [Other ingredients]

[0050] The heat-resistant silicone oil composition of the present invention may contain components other than the above-mentioned components (A) and (B) within the range that does not impair the effects of the present invention. As components other than the above-mentioned components (A) and (B), heat resistance improvers such as metal soaps and aromatic amines may be cited.

[0051] [Method for producing heat-resistant silicone oil composition]

[0052] As a method for producing the heat-resistant silicone oil composition of the present invention, a known method for mixing liquid substances can be used. In particular, since the component (B) of the present invention has excellent compatibility with the organopolysiloxane of the component (A), a uniform composition can be obtained by simply mixing at room temperature (25°C).

[0053] When adding components other than the components (A) and (B) to the composition of the present invention, it is preferred that a mixture prepared by preliminarily dispersing the components in silicone oil by a known method be simply mixed at room temperature (25° C.).

[0054] [Example]

[0055] The present invention will be described in more detail below by way of examples and comparative examples, but may be appropriately modified without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited to the specific examples shown below.

[0056] The kinematic viscosity of the organopolysiloxane is a value measured at 25° C. using a Cannon-Fenske viscometer in accordance with the method described in JIS Z8803:2011.

[0057] Regarding the silicone oil composition of the present invention, a silicone oil composition that meets the standard of "the weight loss rate of the silicone oil composition after heating in an air atmosphere at 300°C for 6 hours is less than 10%, the appearance remains oily, and no separation, precipitation, etc. are observed" will be evaluated as having heat resistance, and a silicone oil composition that does not meet this standard will be evaluated as having no heat resistance.

[0058] Example 1

[0059] Relative kinematic viscosity at 25°C is 100 mm 2 / s dimethyl polysiloxane 100 parts by mass, 18 parts by mass of (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (4) were added, and stirred at room temperature (25°C) for 15 minutes. The obtained silicone composition was placed in an oven at 300°C under air atmosphere and heated for 6 hours. As a result, its weight loss rate was 8.2%. After the heating test, the above composition remained oily and no separation or precipitation occurred. The silicone composition of Example 1 has heat resistance.

[0060] [Chemical formula 5]

[0061]

[0062] Example 2

[0063] Relative kinematic viscosity at 25°C is 100 mm 2 / s dimethyl polysiloxane 100 parts by mass, 33 parts by mass of (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (4) were added, and stirred at room temperature (25°C) for 15 minutes. The obtained silicone composition was placed in an oven at 300°C under air atmosphere and heated for 6 hours. As a result, its weight loss rate was 6.8%. After the heating test, the above composition remained oily and no separation or precipitation occurred. The silicone composition of Example 2 has heat resistance.

[0064] Example 3

[0065] The kinematic viscosity at 25°C is 2000 mm 2 / s dimethyl polysiloxane 100 parts by mass, added 18 parts by mass of (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (4), and stirred at room temperature (25°C) for 15 minutes. The obtained silicone composition was placed in an oven at 300°C under air atmosphere and heated for 6 hours. As a result, its weight loss rate was 4.0%. After the heating test, the above composition remained in an oily state without separation, precipitation, etc. The silicone composition of Example 3 has heat resistance.

[0066] Comparative Example 1

[0067] The kinematic viscosity at 25°C is 100 mm 2 / s dimethyl polysiloxane was placed in an oven at 300°C under air atmosphere and heated for 6 hours. As a result, its weight loss rate was 29.5%. After the heating test, the fluidity of the composition disappeared and it changed into a gel state. The dimethyl polysiloxane of Comparative Example 1 has no heat resistance.

[0068] Comparative Example 2

[0069] The kinematic viscosity at 25°C is 2000 mm 2 / s dimethyl polysiloxane was placed in an oven at 300°C under air atmosphere and heated for 6 hours. As a result, its weight loss rate was 17.5%. After the heating test, the fluidity of the composition disappeared and it changed into a gel state. The dimethyl polysiloxane of Comparative Example 2 has no heat resistance.

Claims

1. A heat-resistant silicone oil composition, comprising: (A) The kinematic viscosity at 25°C measured by a Cannon-Fenske viscometer according to the method described in JIS Z8803:2011 is 50 to 5000 mm 2 / s of organopolysiloxane: 100 parts by mass; and (B) a (poly)thiophene-(poly)siloxane block copolymer having a structure represented by the following formula (1): 10 to 100 parts by mass, [Chemical formula 1] In the formula, R 1 are independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R 2 They are each independently a hydrocarbon group having 1 to 10 carbon atoms, a is 1 to 3, b is 2 to 200, and c is 1 to 40.

2. The heat-resistant silicone oil composition according to claim 1, wherein (A) Component is dimethyl polysiloxane.

3. The heat-resistant silicone oil composition according to claim 1 or 2, wherein The component (B) is a (poly)thiophene-(poly)siloxane block copolymer represented by the following formula (2), [Chemical formula 2] In the formula, R 1 are independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R 2 Each of them is independently a hydrocarbon group having 1 to 10 carbon atoms, each of a is independently 1 to 3, b is 2 to 200, and c is 1 to 40.

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