JP2008031330A - Acrylic rubber composition, molded product composed of the same composition and automotive, electrical/electronic part using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acrylic rubber composition having excellent heat resistance, mechanical properties and low-temperature characteristics. <P>SOLUTION: The acrylic rubber composition comprises (A) an acrylic rubber and (B) a polyorganosiloxane compound. Furthermore, (B) the polyorganosiloxane compound has a structure composed of an R<SB>2</SB>SiO<SB>2/2</SB>unit (wherein, Rs represent each an organic group bindable to Si; and the plurality of Rs may each be same or different) and an R'SiO<SB>3/2</SB>unit (wherein, R' represents a 1-4C alkyl group or a 6-24C aromatic group). The amount of the R<SB>2</SB>SiO<SB>2/2</SB>unit is 70-0 wt.% and the amount of the R'SiO<SB>3/2</SB>unit is 30-100 wt.%. The polyorganosiloxane compound is synthesized into a particle form having 0.01-5 μm volume-average particle diameter in an aqueous system using an emulsifying agent. A molded product composed of the acrylic rubber composition can suitably be used as automotive parts, electrical/electronic parts, etc. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an acrylic rubber composition excellent in heat resistance and excellent in mechanical properties and low-temperature characteristics (cold resistance), a molded article comprising the composition, and an automobile / electric / electronic device comprising the molded article. It relates to electronic parts.

  Acrylic rubber is a polymer mainly composed of acrylate ester, and is generally known as an elastomer material with excellent heat resistance and oil resistance. It is a seal for automobile hose materials or oil seals, O-rings, packings, etc. It is used as a molding material. However, in recent years, in automotive components, the exhaust gas treatment temperature has increased to reduce NOx in automotive engines, and further heat resistance is desired.

  The heat resistance of acrylic rubber tends to be cured and deteriorated, and a general acrylic rubber component has a tendency to cure and deteriorate in the order of methoxyethyl acrylate> butyl acrylate> ethyl acrylate. Therefore, there is a problem that the tendency to cure deterioration increases as the amount of methoxyethyl acrylate and butyl acrylate is increased in order to improve cold resistance, which is a problem of acrylic rubber, and it is difficult to achieve both heat resistance and cold resistance. there were. Conventionally, softening aging inhibitors have been used as additives for improving heat resistance. However, a great effect is not obtained to suppress the curing deterioration of acrylic rubber, and if the amount added is too large, there is a problem that the influence on other properties such as cold resistance and mechanical strength becomes large (for example, non-patent) Reference 1). In addition, when the amount of carbon black, which is a general reinforcing agent for acrylic rubber, is increased in order to suppress a reduction in mechanical strength due to the addition of an anti-aging agent, there is a problem that cold resistance decreases.

As a polyorganosiloxane compound, a resin composition in which a non-silicone polymer is flame-retarded with a silsesquioxane resin mainly composed of RSiO _3/2 units is disclosed (for example, see Patent Document 1). It is also disclosed that polysiloxane containing 80% by weight or more of RSiO _3/2 unit makes thermoplastic non-silicone polymer flame retardant, and that polysiloxane preferably has a number average molecular weight of 2000 or more and 6000 or less for flame resistance. (For example, refer to Patent Document 2). Furthermore, it is disclosed that DQ silicone having a specific molecular weight composed of R ₂ SiO _2/2 units having an aromatic ring and SiO _4/2 units (see, for example, Patent Document 3) also improves flame retardancy of polycarbonate and the like. . However, these have a flame resistance effect only for specific resins and have problems in molding conditions.
Japan Rubber Association, Rubber Industry Handbook <Fourth Edition> P311 to P324 JP 54-36365 A Japanese Examined Patent Publication No. 62-60421 Japanese Patent Laid-Open No. 10-139964

  The present invention relates to an acrylic rubber composition having excellent heat resistance and excellent mechanical properties and low-temperature characteristics (cold resistance), a molded article comprising the composition, and an automobile / electric / electronic device comprising the molded article. The object is to provide electronic parts.

The present inventors have made intensive studies in order to solve the problem, (A) the acrylic rubber was synthesized by using an emulsifier in an aqueous system, R ₂ SiO ₂ in the grain structure having a specific particle size It has been found that an acrylic rubber composition excellent in heat resistance, mechanical properties and low-temperature characteristics can be obtained by blending DT silicone containing _{/ 2} units and R′SiO _3/2 units, and the present invention has been completed. .

That is, the first of the present invention comprises (A) an acrylic rubber and (B) a polyorganosiloxane compound, wherein the (B) polyorganosiloxane compound comprises R ₂ SiO _2/2 units (wherein R represents an organic group capable of bonding to Si, and a plurality of Rs may be the same or different, and R′SiO _3/2 units (wherein R ′ has 1 to 4 carbon atoms) An alkyl group or an aromatic group having 6 to 24 carbon atoms), 70 to 0% by weight of R ₂ SiO _2/2 units, 30 to 100% by weight of R′SiO _3/2 units, In addition, the present invention relates to an acrylic rubber composition, which is a polyorganosiloxane compound synthesized in the form of particles having a volume average particle size of 0.01 to 5 μm using an emulsifier in an aqueous system.

  In a preferred embodiment, the weight average molecular weight of the (B) polyorganosiloxane compound is 300,000 or more.

  In a preferred embodiment, the organic group in the (B) polyorganosiloxane compound comprises a methyl group and an aromatic group, and the molar ratio of methyl group / aromatic group is 10 or less.

  In a preferred embodiment, (B) the polyorganosiloxane is a (B ′) polyorganosiloxane-containing graft copolymer obtained by graft polymerization of a vinyl monomer.

In a preferred embodiment, (B ′) the polyorganosiloxane-containing graft copolymer comprises (B) 95 to 70% by weight of the polyorganosiloxane and 5 to 30% by weight of the graft component.
In a preferred embodiment, 1 to 50 parts by weight of (B) polyorganosiloxane or (B ′) polyorganosiloxane-containing graft copolymer is contained per 100 parts by weight of (A) acrylic rubber.

  In a preferred embodiment, (A) the acrylic rubber contains 0.01 to 20% by weight of a crosslinkable monomer unit in the whole acrylic rubber.

  In a preferred embodiment, 0.005 to 10 parts by weight of (C) a vulcanizing agent is contained per 100 parts by weight of (A) acrylic rubber.

  The second aspect of the present invention is a molded body made of the acrylic rubber composition according to the present invention described above.

  Furthermore, a third aspect of the present invention is an automotive part or an electrical / electronic part that includes the molded body.

The acrylic rubber composition of the present invention was formulated with a DT silicone containing R ₂ SiO _2/2 units and R′SiO _3/2 units in a particle structure having a specific particle size synthesized using an emulsifier in an aqueous system. Therefore, it is excellent in heat resistance, mechanical properties, and low temperature characteristics (cold resistance). Therefore, a molded article made of this acrylic rubber composition can be suitably used for automotive parts and electrical / electronic parts.

  Hereinafter, the composition of the present invention will be described in detail.

<(A) Acrylic rubber>
A publicly known acrylic rubber (A) in the present invention can be used and is not particularly limited. For example, an acrylate monomer based on at least one selected from the group consisting of an alkyl acrylate having an alkyl group having 1 to 12 carbon atoms and an alkoxyalkyl acrylate having an alkoxyalkyl group having 2 to 8 carbon atoms Preferably it is a unit. Furthermore, a copolymer obtained by copolymerizing a small amount of an unsaturated monomer having a crosslinkable group such as a hydroxyl group, an epoxy group, a carboxyl group, a reactive halogen group, an amide group or an unsaturated group is more preferably used.

  The content of the acrylate monomer unit in the acrylic rubber (A) is not particularly limited as long as it is 50% by weight or more. For example, as a unit other than the acrylate monomer unit, When the functional monomer unit is contained, the mechanical strength and compression set of the acrylic rubber composition can be particularly improved by using in combination with a vulcanizing agent described later. As content of a crosslinkable monomer unit, it is preferable that it is 0.01 to 20 weight% in the whole acrylic rubber, and it is more preferable that it is 0.02 to 15 weight%. If the content of the crosslinkable monomer unit is less than 0.01% by weight, the physical properties after crosslinking may not be sufficiently improved. Conversely, if the content is more than 20% by weight, the crosslink density becomes too high and brittle. On the contrary, physical properties may be deteriorated.

  Specific examples of acrylate monomers include, for example, acrylate esters such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, and polyalkylene glycol acrylate. Examples include, but are not limited to, acrylate monomers having an alkylalkoxy group such as methoxymethyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, and butoxyethyl acrylate.

  As the crosslinkable monomer, known crosslinkable components can be widely used. For example, a crosslinkable component such as a unit having an active halogen, a unit having an unsaturated double bond, or a unit having an epoxy group. It is preferable that it is a monomer copolymerizable with the said acrylate-type monomer containing.

  Examples of the monomer having an active halogen include (1) 2-chloroethyl vinyl ether, 2-chloroethyl acrylate, vinyl benzyl chloride, (2) vinyl chloroacetate, allyl chloroacetate, (3 ) Addition reaction product of glycidyl compound such as glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ester and monochloroacetic acid, or (4) alkenyl ester of α- or β-halogen substituted aliphatic monocarboxylic acid, (meth) acrylic acid Examples include halogen-containing monomers such as haloalkyl esters, haloalkylalkenyl esters, haloalkylalkenyl ketones or haloacetoxyalkyl esters, and haloacetyl group-containing unsaturated compounds. In the present invention, (meth) acryl means acrylic and / or methacryl unless otherwise specified.

  Examples of the unit having an unsaturated double bond include conjugated diene monomers such as butadiene, isoprene and cyclopentadiene, unsaturated norbornene monomers such as ethylidene norbornene and vinylidene norbornene, 2-butenyl (meth) acrylate, Examples include alkenyl (meth) acrylates such as 3-methyl-2-butenyl (meth) acrylate, 3-methyl-2-pentyl (meth) acrylate, and 3-methyl-2-hexenyl (meth) acrylate.

  Examples of the unit having an epoxy group include allyl glycidyl ether, glycidyl methacrylate, and glycidyl acrylate.

  In the acrylic rubber (A) used in the present invention, in addition to the above monomer units, monomer units that can be copolymerized with an acrylate-based monomer within a range that does not substantially impair the effects of the present invention. May be contained. Specific examples thereof include vinyl monomers such as ethylene, propylene, acrylonitrile, vinyl acetate, styrene, α-methylstyrene, acrylamide, vinyl chloride, acrylic acid, methyl methacrylate, ethyl methacrylate, methacrylonitrile, vinylidene chloride, Etc. The manufacturing method of an acrylic rubber (A) is not specifically limited, What is necessary is just to superpose | polymerize by a well-known method.

<(B) Polyorganosiloxane compound>
The acrylic rubber composition of the present invention has R ₂ SiO _2/2 units (wherein R represents an organic group capable of bonding to Si, and a plurality of R may be the same or different) and R Having a structure composed of a 'SiO _3/2 unit (wherein R' represents an alkyl group having 1 to 4 carbon atoms or an aromatic group having 6 to 24 carbon atoms), and R ₂ SiO _2/2 unit 70 to 0% by weight, and R'SiO _3/2 units 30-100 wt%, and a volume average particle size by using an emulsifier in an aqueous system is synthesized particulate 0.01 to 5 [mu] m (B) polyorgano A siloxane compound is blended and dispersed in the acrylic rubber (A) serving as a matrix resin, thereby enabling to exhibit heat resistance.

(B) In the polyorganosiloxane compound, the organic group R that can be bonded to the Si atom in the R ₂ SiO _2/2 unit is not particularly limited. For example, the monovalent fat having 1 to 16 carbon atoms Group hydrocarbon group; an alkyl group having 1 to 16 carbon atoms modified with a functional group selected from an epoxy group, a hydroxyl group, a vinyl group, an acrylic group, and a methacryl group; an aromatic group having 6 to 24 carbon atoms, and the like. Examples of the aromatic group include a phenyl group, a cresyl group, a xylenyl group, a naphthyl group, and an anthracenyl group. Moreover, the aromatic group substituted by the halogen atom may be sufficient. As said organic group R, only 1 type may be contained and 2 or more types may be contained. Among these, in consideration of heat resistance and flame retardancy, an aliphatic hydrocarbon group having 1 to 6 carbon atoms and an aromatic group having 6 to 12 carbon atoms are preferable. As the aliphatic hydrocarbon group, a methyl group and an ethyl group are preferable, and a methyl group is more preferable.

In the R′SiO _3/2 unit, R ′ that can be bonded to the Si atom is not particularly limited, and examples thereof include an alkyl group having 1 to 4 carbon atoms and an aromatic group having 6 to 24 carbon atoms. And may be the same or different. Among these, considering flame retardancy and availability, the alkyl group is preferably a methyl group or an ethyl group, and the aromatic group having 6 to 24 carbon atoms is preferably a phenyl group.

(B) As raw materials for the R ₂ SiO _2/2 unit of the polyorganosiloxane compound, dimethyldimethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, methylphenyldiethoxysilane, diethyl Dimethoxysilane, ethylphenyldimethoxysilane, diethyldiethoxysilane, ethylphenyldiethoxysilane, etc., hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexane In addition to cyclic compounds such as sasiloxane (D6) and trimethyltriphenylcyclotrisiloxane, linear or branched organosiloxanes and γ-mercaptopropyl Chill dimethoxysilane, .gamma.-methacryloxypropyl methyl dimethoxy silane, and the like.

(B) As raw materials for R′SiO _3/2 units of polyorganosiloxane compounds, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, Examples thereof include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the like.

The (B) polyorganosiloxane compound in the present invention has R ₂ SiO _2/2 units of 70 to 0% by weight, preferably 50 to 0% by weight, and R′SiO _3/2 units of 30 to 100% by weight, preferably Is preferably composed of 50 to 100% by weight. (B) When R ₂ SiO _2/2 units in the polyorganosiloxane compound is more than 70 wt% or more, tensile properties tend to decrease.

  The (B) polyorganosiloxane compound of the present invention is preferably synthesized into particles having a volume average particle diameter in the range of 0.01 to 5 μm by using an emulsifier in an aqueous system. If the particle diameter of the polyorganosiloxane compound is less than 0.01 μm, it may not be uniformly dispersed in the final molded product, and the heat resistance improving effect may be reduced. Moreover, when the particle diameter of (B) polyorganosiloxane compound exceeds 5 micrometers, the impact resistance of a final molded object may fall.

(B) The particle diameter of the polyorganosiloxane compound can be adjusted by a method of adding an emulsifier, an acid catalyst, and an emulsified liquid (collective charging or continuous dropping). For example, an emulsified liquid obtained by emulsifying a mixture of an emulsifier, a raw material of R ₂ SiO _2/2 units, a raw material of R′SiO _3/2 units and water with 40 to 120 ° C. water containing an acid catalyst with a line mixer or a homogenizer. By adding, (B) polyorganosiloxane compound synthesized in the form of particles can be obtained.

(B) As an emulsifier used for the synthesis | combination of a polyorganosiloxane compound, an anionic emulsifier and a nonionic emulsifier are used suitably. Specific examples of the anionic emulsifier include sodium alkylbenzene sulfonate, sodium lauryl sulfonate, potassium oleate and the like, and sodium dodecylbenzene sulfonate is particularly often used. Specific examples of nonionic emulsifiers include polyoxyethylene nonylphenyl ether and polyoxyethylene lauryl ether. The amount of the emulsifier used is not particularly limited, but is, for example, about 0.5 parts by weight with respect to 100 parts by weight in total of R ₂ SiO _2/2 units and R′SiO _3/2 units.

(B) Examples of the acid catalyst used for the synthesis of the polyorganosiloxane compound include sulfonic acids such as aliphatic sulfonic acid, aliphatic substituted benzenesulfonic acid, and aliphatic substituted naphthalenesulfonic acid, and sulfuric acid, hydrochloric acid, nitric acid, and the like. Mineral acids are mentioned. Among these, aliphatic substituted benzenesulfonic acid is preferable and n-dodecylbenzenesulfonic acid is particularly preferable from the viewpoint of excellent emulsion stability of the organosiloxane. The amount of the acid catalyst used is adjusted depending on the particle size of the polyorganosiloxane compound (B) to be synthesized. For example, the amount of acid catalyst is 0 with respect to a total of 100 parts by weight of R ₂ SiO _2/2 units and R′SiO _3/2 units. .2 to 0.3 parts by weight.

  (B) The heating for the synthesis of the polyorganosiloxane (reaction system temperature) is preferably 40 to 120 ° C, more preferably 60 to 80 ° C in that an appropriate polymerization rate can be obtained.

  In the present invention, seed polymerization may be used in order to control the stability and particle size of the (B) polyorganosiloxane compound. The seed polymer that can be added to the water containing the acid catalyst can be obtained, for example, by an ordinary emulsion polymerization method, but the synthesis method is not particularly limited. The seed polymer may be a rubber component such as butyl acrylate rubber or butadiene rubber, for example, butyl acrylate-styrene copolymer, butyl acrylate-butadiene copolymer, butyl acrylate-acrylonitrile copolymer. Further, it may be a hard polymer such as butyl acrylate-styrene-acrylonitrile copolymer or styrene-acrylonitrile copolymer. (B) From the viewpoint of narrowing the particle size distribution of the polyorganosiloxane compound, the seed polymer preferably has a low molecular weight and a small particle size. The particle diameter of the seed polymer can be appropriately set according to the final particle diameter, but it is usually preferable to set the volume average particle diameter in the range of about 0.01 to 0.1 μm. The amount of seed polymer used in seed polymerization is preferably 0.1 to 10% by weight based on the organosiloxane used.

  The volume average particle diameter of the (B) polyorganosiloxane compound of the present invention is preferably in the range of 0.01 to 5 μm, more preferably 0.05 to 5 m from the viewpoint of the heat resistance and impact resistance of the final molded body. A range of 2 μm is more preferable. The volume average particle diameter can be measured, for example, by using MICROTRAC UPA manufactured by LEED & NORTHRUP INSTRUMENTS.

  The weight average molecular weight of the (B) polyorganosiloxane compound used in the present invention should be set within a range from 300,000 or more to infinitely insoluble in the solvent, from the viewpoint of stable heat resistance not affected by molding conditions. Is preferred. In addition, the weight average molecular weight of (B) polyorganosiloxane compound in the case of melt | dissolving in a solvent can be measured using a gel permeation chromatography (GPC), for example.

  The organic group in the polyorganosiloxane compound (B) in the present invention is preferably substantially composed of a methyl group and an aromatic group from the viewpoint of availability and raw material costs. The molar ratio is more preferably 10 or less, and even more preferably 5 or less.

  In the present invention, in order to improve dispersibility in acrylic rubber and to obtain a good powder, (B) a polyorganosiloxane-containing graft copolymer is obtained by graft polymerization of a vinyl monomer to a polyorganosiloxane compound. It is also preferred to use coalescence. The amount of the vinyl monomer used is 95 to 70% by weight, preferably 90 to 80% by weight of the (B) polyorganosiloxane compound, and 5 to 30% by weight, preferably 10 to 20% by weight of the vinyl monomer. %. When the amount of the vinyl monomer used is less than 5%, the vinyl monomer is not sufficiently coated, and the effect of grafting is not observed. On the other hand, if it exceeds 30% by weight, the tensile strength decreases.

  Examples of the vinyl monomer that is a graft component include aromatic vinyl monomers such as styrene, α-methyl styrene, p-methyl styrene, p-butyl styrene, chlorostyrene, bromostyrene, acrylonitrile, and methacrylonitrile. Vinyl cyanide monomers such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, lauryl methacrylate, glycidyl methacrylate, hydroxyethyl methacrylate (Meth) acrylic acid ester monomers such as itaconic acid, (meth) acrylic acid, fumaric acid, maleic acid and other carboxyl group-containing vinyl monomers, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N- Chill maleimide, N- phenylmaleimide, etc. N-(p-methylphenyl) maleimide monomer such as maleimide and the like. These may be used alone or in combination of two or more.

  In order to obtain a polyorganosiloxane-containing graft copolymer by introducing a chemical bond between (B) the polyorganosiloxane compound and the graft component, a graft crossing agent is used. Examples of the graft crossing agent include p-vinylphenylmethyldimethoxysilane, p-vinylphenylethyldimethoxysilane, 2- (p-vinylphenyl) ethylmethyldimethoxysilane, and 3- (p-vinylbenzoyloxy) propylmethyldimethoxy. Silane, p-vinylphenylmethyldimethoxysilane, vinylmethyldimethoxysilane, tetravinyltetramethylcyclosiloxane, allylmethyldimethoxysilane, mercaptopropylmethyldimethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, (meth) acryloxy Examples thereof include propylmethyldimethoxysilane, (meth) acryloxypropyltrimethoxysilane, (meth) acryloxypropyltriethoxysilane and the like. The proportion of the grafting agent used is preferably 0.01 to 10% by weight, with 100% by weight of the total of (B) polyorganosiloxane compound, ie, organosiloxane and grafting agent. If the amount of the grafting agent used is more than 10% by weight, the low-temperature characteristics (particularly impact resistance) of the final molded product may be deteriorated. If the amount of the grafting agent used is less than 0.1% by weight, the vinyl will be sufficient. Unable to graft the monomer.

  Specific examples of the radical polymerization initiator used in the production of the (B ′) polyorganosiloxane-containing graft copolymer used in the present invention include cumene hydroperoxide, t-butyl hydroperoxide, benzoyl peroxide, t-butyl. Organic peroxides such as peroxyisopropyl carbonate, inorganic peroxides such as potassium persulfate and ammonium persulfate, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile And azo compounds. This radical polymerization is carried out by using ferrous sulfate-sodium formaldehydesulfoxylate-ethylenediaminetetraacetic acid 2Na salt, ferrous sulfate-glucose-sodium pyrophosphate, ferrous sulfate-sodium pyrophosphate-sodium phosphate, etc. When the redox system is used, the polymerization can be completed even at a low polymerization temperature.

  A method for separating the polymer from the latex of the (B) polyorganosiloxane compound or (B ′) polyorganosiloxane-containing graft copolymer obtained by the emulsion polymerization is not particularly limited. Examples include a method of coagulating and heat-treating the latex by adding a metal salt such as magnesium chloride and magnesium sulfate, and separating, washing, dehydrating and drying the resulting coagulated slurry. A spray drying method can also be used.

  In the acrylic rubber composition of the present invention, (B) polyorganosiloxane compound and (B ′) polyorganosiloxane-containing graft copolymer are in the range of 1 to 50 parts by weight with respect to 100 parts by weight of (A) acrylic rubber. It is preferably used at 1 to 20 parts by weight. When the amount of (B) polyorganosiloxane compound or (B ′) polyorganosiloxane-containing graft copolymer exceeds 50 parts by weight, mechanical properties and oil resistance tend to decrease. The effect of improving the sex may not be seen.

<(C) Vulcanizing agent>
The acrylic rubber composition of the present invention may further contain (C) a vulcanizing agent. In the present invention, (C) the vulcanizing agent is a component used for crosslinking (A) the crosslinkable monomer unit of acrylic rubber as a base point to express better rubber elasticity. (C) The vulcanizing agent can be efficiently cross-linked by properly using depending on the type of cross-linkable unit of the acrylic rubber, and it becomes possible to obtain a cross-linked rubber excellent in compression set more easily. In the present invention, a known vulcanizing agent can be used. For example, when the crosslinkable unit of acrylic rubber has an active halogen, polyamine carbamates, organic carboxylic acid ammonium salts, organic carboxylic acid alkali metal salts, sulfur compounds can be used, and the crosslinkable unit of acrylic rubber has an epoxy group. If it has, polyamine carbamates, organic carboxylic acid ammonium salts, dithiocarbamates, organic carboxylic acid alkali metal salts, sulfur compounds can be used, and the crosslinkable unit of acrylic rubber is a unit having an unsaturated double bond Sulfur, organic peroxides, and the like can be suitably used, but are not limited thereto.

  The addition amount of the (C) vulcanizing agent is preferably 0.005 to 10 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the (A) acrylic rubber. (C) If the addition amount of the vulcanizing agent is less than 0.005 parts by weight, the vulcanization may not proceed sufficiently and the effect of improving the physical properties may not be exhibited. When the amount is more than part by weight, physical properties may be deteriorated due to the influence of the remaining vulcanizing agent component.

<Other compounds>
In addition to the above, the acrylic rubber composition of the present invention may contain a lubricant or a thermoplastic resin in the range of 0.1 to 100 parts by weight with respect to 100 parts by weight of (A) acrylic rubber.

  Examples of the lubricant include fatty acids such as stearic acid and palmitic acid, fatty acid metal salts such as calcium stearate, zinc stearate, magnesium stearate, potassium palmitate and sodium palmitate, polyethylene wax, polypropylene wax, and montanic acid wax. Waxes, low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene, polyorganosiloxanes such as dimethylpolysiloxane, octadecylamines, alkyl phosphates, fatty acid esters, amide-based lubricants such as ethylene bisstearamide, 4-fluoro Examples thereof include, but are not limited to, fluororesin powder such as fluorinated ethylene resin, molybdenum disulfide powder, silicone resin powder, silicone rubber powder, and silica. These may be used alone or in combination of two or more. Of these, stearic acid, zinc stearate, calcium stearate, magnesium stearate, and stearyl amide are preferred from the viewpoint of low friction and processability on the resin surface.

  Examples of the thermoplastic resin include polyvinyl chloride resin, polyethylene resin, polypropylene resin, cyclic olefin copolymer resin, polymethyl methacrylate resin, polystyrene resin, polyphenylene ether resin, polycarbonate resin, polyester resin, Examples thereof include polyamide resins, polyacetal resins, polyphenylene sulfide resins, polysulfone resins, polyimide resins, polyetherimide resins, polyetherketone resins, polyetheretherketone resins, polyamideimide resins, and imidized polymethylmethacrylate resins. These may be used alone or in combination of two or more.

  The composition of the present invention further includes a stabilizer (anti-aging agent, light stabilizer, ultraviolet absorber, etc.), inorganic filler, flexibility imparting agent, flame retardant, mold release agent, antistatic agent, depending on the required properties. Agents, antibacterial and antifungal agents may be added. These additives may be appropriately selected and used in appropriate amounts according to the required physical properties, workability, and the like.

  Examples of the stabilizer (anti-aging agent, light stabilizer, ultraviolet absorber, etc.) include the following compounds, but are not limited thereto.

  Anti-aging agents include phenyl α-naphthylamine (PAN), octyldiphenylamine, N, N′-diphenyl-p-phenylenediamine (DPPD), N, N′-di-β-naphthyl-p-phenylenediamine (DNPD). N- (1,3-dimethyl-butyl) -N′-phenyl-p-phenylenediamine, N-phenyl-N′-isopropyl-p-phenylenediamine (IPPN), N, N′-diallyl-p-phenylene Diamine, phenothiazine derivative, diallyl-p-phenylenediamine mixture, alkylated phenylenediamine, 4,4′-α, α-dimethylbenzyldiphenylamine, p, p-toluenesulfonylaminodiphenylamine, N-phenyl-N ′-(3- Methacryloyloxy-2-hydropropyl) -p-pheny Diamines, diallylphenylenediamine mixtures, diallyl-p-phenylenediamine mixtures, N- (1-methylheptyl) -N-phenyl-p-phenylenediamine, amine-based antioxidants such as diphenylamine derivatives, 2-mercaptobenzimidazole (MBI) ) Imidazole antioxidants, phenol-based antioxidants such as 2,6-di-t-butyl-4-methylphenol, dithiocarbamate antioxidants such as nickel diethyl-dithiocarbamate, triphenyl phosphite Secondary anti-aging agents such as

  Examples of light stabilizers and ultraviolet absorbers include 4-t-butylphenyl salicylate, 2,4-dihydroxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, ethyl-2-cyano-3,3′-. Diphenyl acrylate, 2-ethylhexyl-2-diamino-3,3′-diphenyl acrylate, 2-hydroxy-5-chlorobenzophenone, 2-hydroxy-4-methoxybenzophenone-2-hydroxy-4-octoxybenzophenone, monoglycol sari Examples include tyrates, oxalic acid amides, 2,2 ′, 4,4′-tetrahydroxybenzophenone, and the like. These stabilizers may be used alone or in combination of two or more.

  Examples of inorganic fillers include titanium oxide, zinc sulfide, zinc oxide, carbon black, calcium carbonate, calcium silicate, clay, kaolin, silica, mica powder, alumina, glass fiber, metal fiber, california titanate, asbestos. , Wollastonite, mica, talc, glass flake, milled fiber, metal powder, and the like, but are not limited thereto. These may be used alone or in combination. Among these, silica is preferable from the viewpoint of the high elastic modulus of the composition, and carbon black and titanium oxide are preferable from the viewpoint that the composition can be used as weather resistance and a pigment.

  Examples of the flexibility-imparting agent include plasticizers, softeners, oligomers, oils (animal oil, vegetable oil, etc.) usually used in thermoplastic resins and rubbers, petroleum fractions (kerosene, light oil, heavy oil, naphtha, etc.). However, it is preferable to use those having excellent affinity with (A) acrylic rubber, (B) polyorganosiloxane compound and polyorganosiloxane-containing graft copolymer. Among these, low-volatility plasticizers with low heat loss are adipic acid derivatives, phthalic acid derivatives, glutaric acid derivatives, trimellitic acid derivatives, pyromellitic acid derivatives, polyester plasticizers, glycerin derivatives, epoxy derivatives polyester polymerized plastics. An agent, a polyether polymerization type plasticizer and the like are preferably used.

  Examples of the softener include process oils such as petroleum process oils such as paraffinic oils, naphthenic process oils, and aromatic process oils.

  Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, di- (2-ethylhexyl) phthalate, diheptyl phthalate, diisodecyl phthalate, di-n-octyl phthalate, and phthalic acid. Phthalic acid derivatives such as diisononyl, ditridecyl phthalate, octyl decyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate; isophthalic acid derivatives such as dimethyl isophthalate; tetrahydrophthal such as di- (2-ethylhexyl) tetrahydrophthalic acid Acid derivatives: dimethyl adipate, dibutyl adipate, di-n-hexyl adipate, di- (2-ethylhexyl) adipate, dioctyl adipate, isononyl adipate, diisodecyl adipate, dibutyl diglycol adipate, etc. Adipic acid derivatives; azelaic acid derivatives such as di-2-ethylhexyl azelate; sebacic acid derivatives such as dibutyl sebacate; dodecanedioic acid derivatives; maleic acid derivatives such as dibutyl maleate and di-2-ethylhexyl maleate; fumaric acid Fumaric acid derivatives such as dibutyl; p-oxybenzoic acid derivatives such as 2-ethylhexyl p-oxybenzoate; trimellitic acid derivatives such as tris-2-ethylhexyl trimellitic acid; pyromellitic acid derivatives; citric acid derivatives such as acetyltributyl citrate Itaconic acid derivative; oleic acid derivative; ricinoleic acid derivative; stearic acid derivative; other fatty acid derivative; sulfonic acid derivative; phosphoric acid derivative; glutaric acid derivative; dibasic acid such as adipic acid, azelaic acid, phthalic acid and glycol Polyester plasticizers that are polymers with monohydric alcohol, etc., glycol derivatives, glycerin derivatives, paraffin derivatives such as chlorinated paraffins, epoxy derivatives polyester polymerized plasticizers, polyether polymerized plasticizers, ethylene carbonate, propylene Examples thereof include carbonate derivatives such as carbonate, benzenesulfonic acid derivatives such as N-butylbenzeneamide, and the like, but are not limited to these, such as those widely marketed as plasticizers for rubber or thermoplastic resins. Various plasticizers can be used. Commercially available plasticizers include Thiocol TP (manufactured by Morton), Adekasizer O-130P, C-79, UL-100, P-200, RS-735 (Asahi Denka Kogyo Co., Ltd.), Sunsosizer N-400 (manufactured by Shin Nippon Rika Co., Ltd.), BM-4 (manufactured by Daihachi Chemical Industry Co., Ltd.), EHPB (manufactured by Ueno Pharmaceutical Co., Ltd.), UP-1000 (manufactured by Toagosei Co., Ltd.), etc. Can be given.

  Examples of the oil include vegetable oils such as castor oil, cottonseed oil, sesame oil, rapeseed oil, soybean oil, palm oil, palm oil, peanut oil, pine oil, tall oil, sesame oil, and camellia oil.

  Examples of other flexibility imparting agents include polybutene oil, spindle oil, machine oil, tricresyl phosphate, and the like.

  Examples of the flame retardant include, but are not limited to, triphenyl phosphate, tricresyl phosphate, decabromobiphenyl, decabromobiphenyl ether, and antimony trioxide. These flame retardants may be used alone or in combination of two or more.

  In order to improve the compatibility between (A) acrylic rubber and (B) polyorganosiloxane compound or (B ′) polyorganosiloxane-containing graft copolymer, various graft polymers and block polymers are used as compatibilizers. May be added.

  Examples of the compatibilizer include the Kraton series (manufactured by Shell Japan Co., Ltd.), the Tuftec series (manufactured by Asahi Kasei Kogyo Co., Ltd.), Dynalon (manufactured by Nippon Synthetic Rubber Co., Ltd.), and Epofriend (manufactured by Daicel Chemical Industries, Ltd.). ), Septon (manufactured by Kuraray Co., Ltd.), Nofaloy (manufactured by Nippon Oil & Fats Co., Ltd.), Lexpearl (manufactured by Nippon Polyolefin Co., Ltd.), Bond First (manufactured by Sumitomo Chemical Co., Ltd.), Bondine (Sumitomo Chemical Industries ( Co., Ltd.), Admer (Mitsui Chemicals Co., Ltd.), Umex (Sanyo Kasei Kogyo Co., Ltd.), VMX (Mitsubishi Chemical Co., Ltd.), Modiper (Nippon Yushi Co., Ltd.), Staphyroid (Takeda) Examples include commercial products such as Yakuhin Kogyo Co., Ltd. and Reeta (Toagosei Co., Ltd.). These can be appropriately selected and used according to the combination of (A) the polyorganosiloxane compound used to supplement the physical properties of the acrylic rubber and the polyorganosiloxane-containing graft copolymer.

  The acrylic rubber composition according to the present invention is kneaded with a predetermined amount of each component as described above in a mixer such as a Banbury mixer, a kneader, an intermixer, a two-roll roll, or a plast mill used for general rubber kneading. It is possible to manufacture easily.

  The acrylic rubber composition thus obtained is molded into a shape according to the molding purpose by, for example, a molding method such as injection molding or hot press molding, and vulcanized as necessary to form a molded product. As the vulcanization temperature, a temperature of 120 ° C. or higher is usually suitable, preferably 140 to 200 ° C., and vulcanization is performed at this temperature for about 1 to 30 minutes. Further, if necessary, post-vulcanization can be performed at a temperature of about 140 to 200 ° C. for about 1 to 48 hours to improve physical properties.

  The acrylic rubber composition of the present invention can be used as a molded product. Examples of the molding method include arbitrary molding methods such as extrusion molding, compression molding, blow molding, calendar molding, vacuum molding, foam molding, and injection molding.

  The rubber material (molded product) obtained from the acrylic rubber composition of the present invention can be widely used mainly for applications such as gaskets, packing, sealing materials, vibration proofing, waterproofing, and exercise equipment. As these uses, for example, it is suitably used for automobiles, electricity, electronics, architecture, sporting goods, particularly in the automobile field and electrical / electronic parts.

  For example, in the automobile field, for example, as a body part, it can be used as a sealing material for maintaining airtightness, an anti-vibration material for glass, an anti-vibration material for vehicle body parts, particularly a wind seal gasket and a door glass gasket. Moreover, it can be used as a chassis component for vibration-proof and sound-proof engines and suspension rubbers, particularly engine mount rubbers. Furthermore, as engine parts, they can be used for hoses for cooling, fuel supply, exhaust control, etc., sealing materials for engine oil, and the like. It can also be used for exhaust gas cleaning device parts and brake parts.

  As electrical and electronic parts, it can be used for packing, O-rings, belts and the like. Specifically, decorations for lighting fixtures, waterproof packings, anti-vibration rubbers, insect-proof packings, anti-vibration / sound absorption and air sealing materials for cleaners, drip-proof covers for electric water heaters, waterproof packings, heater parts Packing, electrode packing, safety valve diaphragm, hose for sake cans, waterproof packing, solenoid valve, waterproof packing for steam microwave oven and jar rice cooker, water tank packing, water absorption valve, water receiving packing, connection hose, belt, heat insulation Oil packing for combustion equipment such as heater packing, steam outlet seal, O-ring, drain packing, pressure tube, blower tube, feed / intake packing, anti-vibration rubber, oil filler packing, oil meter packing, oil feed tube, Speaker gaskets, speaker edges, turntables for acoustic equipment such as diaphragm valves and air pipes Seat, belts, pulleys, and the like.

  In the construction field, it can be used for structural gaskets (zipper gaskets), air membrane roof materials, waterproof materials, fixed sealing materials, vibration-proof materials, sound-proof materials, setting blocks, sliding materials, and the like.

  In the sports field, it can be used for all-weather pavement materials and gymnasium floors as sports floors, shoe sole materials and midsole materials as sports shoes, and golf balls as ball for ball games.

  In the field of anti-vibration rubber, it can be used as anti-vibration rubber for automobiles, anti-vibration rubber for railway vehicles, anti-vibration rubber for aircraft, anti-vibration materials, and the like.

  In the marine and civil engineering fields, structural materials include rubber expansion joints, bearings, waterstops, waterproof sheets, rubber dams, elastic pavements, anti-vibration pads, protective bodies, etc., rubber molds, rubber packers, rubber skirts as construction secondary materials , Sponge mats, mortar hoses, mortar strainers, etc., rubber sheets, air hoses, etc. as construction auxiliary materials, rubber buoys, wave-absorbing materials, etc. as safety measures products, oil fences, silt fences, antifouling materials, marine hoses, etc. Can be used for draging hoses, oil skimmers, etc. In addition, it can be used for sheet rubber, mats, foam boards and the like.

  Next, the composition of the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. Prior to the description of the examples, an evaluation method (test method) for various properties and a method for producing a molded article for evaluation will be described.

<Test method>
(Volume average particle diameter)
The volume average particle size of the seed polymer and polyorganosiloxane particles was measured in a latex state. The volume average particle size (μm) was measured by a light scattering method using MICROTRAC UPA manufactured by LEED & NORTHRUUP INSTRUMENTS as a measuring device.

(Weight average molecular weight of polyorganosiloxane)
The weight average molecular weight of the polyorganosiloxane was converted from the GPC measurement data using a calibration curve prepared with a polystyrene standard sample.

(Tensile property evaluation method)
According to the method described in JIS K7113, measurement was performed using an autograph AG-10TB type manufactured by Shimadzu Corporation. Measurement was performed at n = 3, and the average values of strength (MPa) and elongation (%) when the test piece was broken were adopted. A test piece having a shape of 2 (1/3) shape and a thickness of about 2 mm was used. The test was conducted at 23 ° C. and a test speed of 500 mm / min. In principle, the test piece was conditioned at a temperature of 23 ± 2 ° C. and a relative humidity of 50 ± 5% for 48 hours or more before the test.

(Heat resistance evaluation method)
After holding a test piece of type 2 (1/3) in an oven at 150 ° C. for 168 hours, the tensile strength (breaking strength) change rate (%) was measured by the above-described tensile property evaluation method. Asked.
Tensile strength (breaking strength) change rate (%) = (tensile strength after heat test / tensile strength before heat test) × 100-100

(Low temperature embrittlement)
In accordance with JIS K7216, a 2 mm thick molded product sheet was cut into 38 × 6 mm, and a low temperature embrittlement temperature measuring device “Standard Model S type (dry ice type)” (manufactured by Toyo Seiki Co., Ltd.) was used. The low temperature embrittlement temperature was measured using a methanol mixture as a refrigerant.

<Method for producing molded article for evaluation>
Predetermined amounts of (A) acrylic rubber, carbon black, lubricant, and antioxidant using a kneader “DS1-5MHB-E” (manufactured by Moriyama Co., Ltd.) under predetermined conditions (sample amount: 700 g, chamber set temperature: Kneading was performed at 50 ° C., preheating time: none, front blade rotation speed: 20 rpm, rear blade rotation speed: 14.7 rpm, chamber volume: 1 L, kneading time: 8 minutes. Thereafter, the front blade speed was changed to 34 rpm and the rear blade speed was changed to 24.9 rpm, and kneaded for 4 minutes to obtain a lump sample. A predetermined amount of the lump sample thus obtained was subjected to predetermined conditions (sample amount: 45 g, chamber set temperature: 80 ° C., preheating time: none using a plastmill “MODEL20C200” (manufactured by Toyo Seiki Co., Ltd.). , Screw rotation: 25 rpm, blade: roller type R60B biaxial, chamber capacity: 60CC, mixer: ticker anti-abrasion roller mixer R60HT, kneading time: 1 minute). Further, (B) polyorganosiloxane compound particles or (B ′) polyorganosiloxane-containing graft copolymer particles were added, and kneading was continued for 7 minutes. After kneading was stopped and the resin temperature was cooled to 70 ° C., 1.5 parts by weight of ammonium benzoate was added as a vulcanizing agent to 100 parts by weight of acrylic rubber, and kneaded for 8 minutes under predetermined conditions. A lump sample was obtained. The massive sample thus obtained was pressed for 35 minutes at a predetermined condition (press temperature: 170 ° C., press pressure: 5 MPa) using a press machine “NSF-50” (manufactured by Shinto Metal Industry Co., Ltd.). Thereafter, it was press-molded according to 2 MPa and cooled to 30 ° C. to obtain a sheet-like molded body having a thickness of 2 mm. Further, the sheet-shaped molded body was annealed at 170 ° C. for a predetermined time, and each evaluation shown in Table 1-2 was performed using the obtained sheet-shaped molded body.

<Production Example of Polyorganosiloxane Compound and Polyorganosiloxane-Containing Graft Copolymer>
(Production Example 1)
In a 5-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet, monomer addition port and thermometer, 400 parts by weight of water and 12 parts by weight (solid content) of 10% by weight aqueous sodium dodecylbenzenesulfonate After mixing, the temperature was raised to 50 ° C., and after the liquid temperature reached 50 ° C., nitrogen substitution was performed. Thereafter, 10 parts by weight of butyl acrylate and 3 parts by weight of t-dodecyl mercaptan were added. After 30 minutes, 0.01 parts by weight of paramentane hydroperoxide (solid content), 0.3 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.01 parts by weight of disodium ethylenediaminetetraacetate (EDTA), first sulfuric acid sulfate 0.0025 part by weight of iron was added and stirred for 1 hour. A mixed solution of 90 parts by weight of butyl acrylate, 27 parts by weight of t-dodecyl mercaptan and 0.09 parts by weight of paramentane hydroperoxide (solid content) was continuously added over 3 hours. Thereafter, post-polymerization was performed for 2 hours to obtain a latex (S-1) containing a seed polymer having a volume average particle size of 0.03 μm.
Next, in a 5-neck flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port, and thermometer, 500 parts by weight of pure water (total amount of water including various dilution water), the above-mentioned seed 2 parts by weight (solid content) of polymer was charged. Thereafter, it is separately composed of 100 parts by weight of pure water, 0.5 part by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 100 parts by weight of octamethylcyclotetrasiloxane, and 1 part by weight of methacryloxypropylmethyldimethoxysilane. The mixture was stirred with a homogenizer at 7000 rpm for 5 minutes to prepare an emulsion of a polyorganosiloxane-forming component and added all at once.
Then, after adding 1.5 weight part (solid content) of 10 weight% dodecylbenzenesulfonic acid aqueous solution, it heated up to 80 degreeC under nitrogen stream, stirring a system. After reaching 80 ° C., stirring was continued for 7 hours at 80 ° C., then cooled to 25 ° C. and allowed to stand for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and latex (L-1) containing polyorganosiloxane particles was obtained. The obtained latex (L-1) had a volume average particle size of 0.22 μm.
Next, in a 5-neck flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port and thermometer, 250 parts by weight of pure water (total amount of water including various dilution waters), the above-mentioned poly 2 parts by weight (solid content) of latex (L-1) containing organosiloxane particles was charged. Thereafter, a mixture comprising 98 parts by weight of pure water, 0.49 parts by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 49 parts by weight of methyltrimethoxysilane, and 49 parts by weight of octamethylcyclotetrasiloxane was prepared. The emulsion of the polyorganosiloxane formation component was prepared by stirring at 7000 rpm for 5 minutes with a homogenizer, and added all at once.
Then, after adding 1.5 weight part (solid content) of 10 weight% dodecylbenzenesulfonic acid aqueous solution, it heated up to 80 degreeC under nitrogen stream, stirring a system. After reaching 80 ° C., stirring was continued for 7 hours at 80 ° C., then cooled to 25 ° C. and left for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and a latex containing polyorganosiloxane particles was obtained. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 95 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane powder.

(Production Example 2)
A 5-neck flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port, and thermometer was prepared in Production Example 1 with 250 parts by weight of pure water (total amount of water including various dilution waters). 2 parts by weight (solid content) of latex (L-1) containing polyorganosiloxane particles was charged. Thereafter, 98 parts by weight of pure water, 0.49 parts by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 49 parts by weight of methyltrimethoxysilane, 49 parts by weight of octamethylcyclotetrasiloxane, methacryloxypropylmethyldimethoxy A mixture composed of 2.94 parts by weight of silane was stirred with a homogenizer at 7000 rpm for 5 minutes to prepare a polyorganosiloxane-forming component emulsion, which was added all at once.
Subsequently, 2 parts by weight (solid content) of a 10% by weight aqueous dodecylbenzenesulfonic acid solution was added, and then the system was heated to 80 ° C. under a nitrogen stream while stirring the system. After reaching 80 ° C., stirring was continued for 7 hours at 80 ° C., then cooled to 25 ° C. and left for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and latex (L-2) containing polyorganosiloxane particles was obtained. The obtained latex (L-2) had a volume average particle size of 0.55 μm.
Next, in a five-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer addition port, and a thermometer, 400 parts by weight of pure water (including the amount brought in from the latex containing polyorganosiloxane particles) , And 90 parts by weight (solid content) of latex (L-2) containing the above-mentioned polyorganosiloxane particles were charged, and the temperature was raised to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then ethyl acrylate A mixture of 10 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) was added dropwise over 1 hour, and after the addition was completed, the mixture was further stirred for 1 hour to obtain a polyorganosiloxane-containing graft polymer latex. Obtained. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane-containing graft polymer are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 95 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

(Production Example 3)
In a five-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet, monomer addition port and thermometer, 400 parts by weight of pure water (including the amount brought in from latex containing polyorganosiloxane particles), and production 90 parts by weight (solid content) of the latex (L-2) containing the polyorganosiloxane particles prepared in Example 2 was charged, and the temperature was raised to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then methyl methacrylate. Add a mixture of 7.5 parts by weight, ethyl acrylate 2.5 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) dropwise over 1 hour, and continue stirring for 1 hour after the addition is complete. To obtain a latex of a polyorganosiloxane-containing graft polymer. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane-containing graft polymer are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 75 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

(Production Example 4)
In a 5-neck flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port, and thermometer, 500 parts by weight of pure water (total amount of water including various dilution water) was prepared in Production Example 1. After charging 2 parts by weight (solid content) of seed polymer (S-1) and 3 parts by weight (solid content) of a 10 wt% aqueous solution of dodecylbenzenesulfonic acid, the temperature was raised to 80 ° C under a nitrogen stream while stirring the system. . Thereafter, it is separately composed of 100 parts by weight of pure water, 0.5 part by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 100 parts by weight of octamethylcyclotetrasiloxane, and 1 part by weight of methacryloxypropylmethyldimethoxysilane. The mixture was stirred with a homogenizer at 7000 rpm for 5 minutes to prepare an emulsion of a polyorganosiloxane-forming component and added all at once.
After reaching 80 ° C., the above emulsion was continuously added dropwise over 3 hours, and stirring was continued for 4 hours. After completion of stirring, the mixture was cooled to 25 ° C. and left for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and latex (L-3) containing polyorganosiloxane particles was obtained. The obtained latex (L-3) had a volume average particle size of 0.22 μm.
Next, in a 5-neck flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port, thermometer, 500 parts by weight of pure water (total amount of water including various dilution water), the above-mentioned poly 2 parts by weight (solid content) of latex (L-3) containing organosiloxane particles was charged. Thereafter, 98 parts by weight of pure water, 0.49 parts by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 73.5 parts by weight of methyltrimethoxysilane, 24.5 parts by weight of octamethylcyclotetrasiloxane, methacrylate A mixture composed of 2.94 parts by weight of roxypropylmethyldimethoxysilane was stirred with a homogenizer at 7000 rpm for 5 minutes to prepare an emulsion of a polyorganosiloxane-forming component, which was added all at once.
Subsequently, 2 parts by weight (solid content) of a 10% by weight aqueous dodecylbenzenesulfonic acid solution was added, and then the system was heated to 80 ° C. under a nitrogen stream while stirring the system. After reaching 80 ° C., stirring was continued for 7 hours at 80 ° C., then cooled to 25 ° C. and left for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and latex (L-4) containing polyorganosiloxane particles was obtained. The obtained latex (L-4) had a volume average particle size of 0.47 μm.
Next, in a five-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer addition port, and a thermometer, 850 parts by weight of pure water (including the amount brought in from the latex containing polyorganosiloxane particles) , And 90 parts by weight (solid content) of latex (L-4) containing the above-mentioned polyorganosiloxane particles, and the temperature was raised to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then ethyl acrylate A mixture of 10 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) was added dropwise over 1 hour, and after the addition was completed, the mixture was further stirred for 1 hour to obtain a polyorganosiloxane-containing graft polymer latex. Obtained. Table 1-1 shows the volume average particle size and weight average molecular weight of the polyorganosiloxane-containing graft polymer.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of a 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 95 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

(Production Example 5)
In a 5-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet, monomer addition port and thermometer, 850 parts by weight of pure water (including the amount brought in from latex containing polyorganosiloxane particles), and production 90 parts by weight (solid content) of the latex (L-4) containing the polyorganosiloxane particles prepared in Example 4 was charged, and the temperature was raised to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then methyl methacrylate. Add a mixture of 7.5 parts by weight, ethyl acrylate 2.5 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) dropwise over 1 hour, and continue stirring for 1 hour after the addition is complete. To obtain a latex of a polyorganosiloxane-containing graft polymer. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 75 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

(Production Example 6)
500 parts by weight of pure water (total amount of water including various dilution waters) was charged into a five-necked flask equipped with a stirrer, reflux cooling water, nitrogen inlet, monomer addition port, and thermometer. Thereafter, a mixture comprising 100 parts by weight of pure water, 0.5 part by weight of 15% by weight aqueous sodium dodecylbenzenesulfonate (solid content), 100 parts by weight of methyltrimethoxysilane, and 3 parts by weight of methacryloxypropylmethyldimethoxysilane. Was stirred with a homogenizer at 7000 rpm for 5 minutes to prepare a polyorganosiloxane-forming component emulsion, which was added all at once.
Subsequently, 3 parts by weight (solid content) of a 10% by weight aqueous solution of dodecylbenzenesulfonic acid was added, and the system was heated to 80 ° C. under a nitrogen stream while stirring the system. After reaching 80 ° C., stirring was continued for 7 hours at 80 ° C., then cooled to 25 ° C. and allowed to stand for 18 hours. Thereafter, the pH was adjusted to 6.5 with sodium hydroxide to complete the polymerization, and latex (L-5) containing polyorganosiloxane particles was obtained. The obtained latex (L-5) had a volume average particle size of 0.35 μm.
Next, in a five-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer addition port, and a thermometer, 950 parts by weight of pure water (including the amount brought in from latex containing polyorganosiloxane particles) , And 90 parts by weight (solid content) of latex (L-5) containing the polyorganosiloxane particles described above were charged, and the system was heated to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then ethyl acrylate A mixture of 10 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) was added dropwise over 1 hour, and after the addition was completed, the mixture was further stirred for 1 hour to obtain a polyorganosiloxane-containing graft polymer latex. Obtained. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane-containing graft polymer are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 95 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

(Production Example 7)
In a 5-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet, monomer addition port and thermometer, 950 parts by weight of pure water (including the amount brought in from latex containing polyorganosiloxane particles), and production 90 parts by weight (solid content) of latex (L-5) containing polyorganosiloxane particles prepared in Example 6 was charged, and the temperature was raised to 40 ° C. under a nitrogen stream while stirring the system. After reaching 40 ° C., 0.39 parts by weight of sodium formaldehyde sulfoxylate (SFS), 0.0048 parts by weight of disodium ethylenediaminetetraacetate (EDTA) and 0.0012 parts by weight of ferrous sulfate were added, and then methyl methacrylate. Add a mixture of 7.5 parts by weight, ethyl acrylate 2.5 parts by weight and cumene hydroperoxide 0.037 parts by weight (solid content) dropwise over 1 hour, and continue stirring for 1 hour after the addition is complete. To obtain a latex of a polyorganosiloxane-containing graft polymer. The volume average particle diameter and the weight average molecular weight of this polyorganosiloxane are shown in Table 1-1.
The latex was diluted with pure water to a solid content concentration of 15% by weight, and then 4 parts by weight (solid content) of 25% by weight calcium chloride aqueous solution was added to obtain a coagulated slurry. The coagulated slurry was heated to 75 ° C., cooled to 50 ° C., dehydrated, and dried to obtain a polyorganosiloxane-containing graft copolymer powder.

<Examples of acrylic rubber composition>
(Example 1)
As an inorganic filler, 100 parts by weight of acrylic rubber (manufactured by Nippon Zeon, trade name AR31) and 5 parts by weight of the polyorganosiloxane obtained in Production Example 1, 2 parts by weight of antioxidant (trade name Nowguard 445, made by calcium Shiraishi) 45 parts by weight of carbon black (Seast 3, manufactured by Tokai Carbon), 1 part by weight of stearic acid (manufactured by Nippon Oil & Fats) as a lubricant and 1 part by weight of Greg G-8205 (Dainippon Ink & Chemicals), ammonium benzoate as a vulcanizing agent 1 .5 parts by weight was obtained according to a predetermined method using a plastmill “MODEL20C200” (manufactured by Toyo Seiki Co., Ltd.) to obtain a lump sample. The lump sample thus obtained was press-molded according to a predetermined method to obtain a sheet-like molded body having a thickness of 2 mm. Further, the sheet-like molded body was annealed at 170 ° C. for 8 hours, and the obtained sheet-like molded body was measured for tensile properties, heat resistance, and low temperature embrittlement. The evaluation results for each characteristic are shown in Table 1-2.

(Examples 2 to 7)
In the method described in Example 1, in place of polyorganosiloxane, the polyorganosiloxane-containing graft copolymers obtained in Production Examples 2 to 7 were added, respectively, and thereafter, a sheet-like molded body was similarly prepared and evaluated. Went. The evaluation results for each characteristic are shown in Table 1-2.

(Comparative Example 1)
100 parts by weight of acrylic rubber (made by Nippon Zeon, trade name AR31), 2 parts by weight of antioxidant (made by calcium Shiraishi, trade name Nowguard 445), 50 parts by weight of carbon black (Shiest 3, made by Tokai Carbon) as an inorganic filler As a lubricant, 1 part by weight of stearic acid (manufactured by NOF Corporation), 1 part by weight of Greg G-8205 (Dainippon Ink Chemical Co., Ltd.) and 1.5 parts by weight of ammonium benzoate were subjected to a plastmill “MODEL20C200” (Toyo Seiki). The sample of the lump was obtained using Co., Ltd. The lump sample thus obtained was press-molded according to a predetermined method to obtain a sheet-like molded body having a thickness of 2 mm. Further, the sheet-like molded body was annealed at 170 ° C. for 8 hours, and the obtained sheet-like molded body was measured for tensile properties, heat resistance, and low temperature embrittlement. The evaluation results for each characteristic are shown in Table 1-2.

As is clear from Table 1-2, curing deterioration after the heat resistance test was made by adding polyorganosiloxane or polyorganosiloxane-containing graft copolymer comprising R ₂ SiO _2/2 units / R′SiO _3/2 units. It can be seen that the heat resistance is not improved or the deterioration of curing is small and the heat resistance can be improved. Moreover, the deterioration of the tensile properties and the cold resistance due to the addition of the polyorganosiloxane or the polyorganosiloxane-containing graft copolymer is not seen, and it can be seen that both heat resistance and cold resistance are compatible.

Claims (11)

(A) acrylic rubber and (B) a polyorganosiloxane compound,
(B) the polyorganosiloxane compound is an R ₂ SiO _2/2 unit (wherein R represents an organic group capable of bonding to Si, and a plurality of R may be the same or different) and R′SiO _3/2 unit (wherein R ′ represents an alkyl group having 1 to 4 carbon atoms or an aromatic group having 6 to 24 carbon atoms), and R ₂ SiO _2/2 unit Polyorganosiloxane compound which is 70 to 0% by weight, R'SiO _3/2 unit is 30 to 100% by weight, and is synthesized in the form of particles having a volume average particle diameter of 0.01 to 5 μm using an emulsifier in an aqueous system. An acrylic rubber composition, characterized in that   (B) The acrylic rubber composition according to claim 1, wherein the polyorganosiloxane compound has a weight average molecular weight of 300,000 or more.   (B) The organic group in the polyorganosiloxane compound is composed of a methyl group and an aromatic group, and the molar ratio of methyl group / aromatic group is 10 or less. Acrylic rubber composition.   The acrylic resin according to any one of claims 1 to 3, wherein the (B) polyorganosiloxane compound is a (B ') polyorganosiloxane-containing graft copolymer obtained by graft polymerization of a vinyl monomer. Rubber composition.   The (B ') polyorganosiloxane-containing graft copolymer comprises 95 to 70% by weight of polyorganosiloxane and 5 to 30% by weight of a graft component, according to any one of claims 1 to 4. Acrylic rubber composition.   1 to 50 parts by weight of (B) a polyorganosiloxane compound or (B ′) a polyorganosiloxane-containing graft copolymer with respect to 100 parts by weight of (A) acrylic rubber, The acrylic rubber composition according to any one of 5.   The acrylic rubber composition according to any one of claims 1 to 6, wherein (A) the acrylic rubber contains 0.01 to 20% by weight of a crosslinkable monomer unit in the entire acrylic rubber.   The acrylic rubber composition according to any one of claims 1 to 7, wherein 0.005 to 10 parts by weight of (C) a vulcanizing agent is contained with respect to 100 parts by weight of (A) acrylic rubber.   The molded object which consists of an acrylic rubber composition in any one of Claims 1-8.   An automotive part comprising the molded body according to claim 9. An electrical / electronic component comprising the molded body according to claim 9.