JPH09157338A - Graft copolymer and thermoplastic resin composition containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic resin compsn. excellent in the balance among low-temp. impact resistance, surface hardness, colorability with a pigment, and molded appearance. SOLUTION: This graft copolymer is obtd. by grafting an arom. alkenyl compd., a methacrylic ester, an acrylic ester, a vinyl cyanide compd., etc., onto a composite rubber comprising 60-80wt.% alkyl (meth)acrylate rubber and 20-40wt.% polyorganosiloxane having polymerizable vinyl groups, a gel content of 60-95wt.%, and a degree of swelling of 10-30 in toluene, and has a wt. average particle size of 0.01-0.20μm. A thermoplastic resin compsn. contg. the graft copolymer is prepd.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an impact resistant resin which is excellent in impact resistance and pigment coloring property.

[0002]

2. Description of the Related Art Generally, when a resin material is used for industrial purposes, the appearance after molding, mechanical strength, and when used without painting, discoloration due to sunlight or rainfall, little deterioration of physical properties, so-called weather resistance is good. At the same time, the color developability and the pigment colorability when a colorant such as a pigment is mixed must be good.

In particular, in resin parts used in the vehicle field, it is necessary that the molding appearance, impact strength and pigment coloration are at a high level. Of these, the impact strength is generally A
It is evaluated by the Izod impact strength according to the STM D256 test method. For example, in order to determine whether it can be used as a material for automobile exteriors, in addition to the impact strength at room temperature, a low temperature atmosphere of -30 ° C or -40 ° C is used. Judging by impact strength. The Izod impact strength under low temperature atmosphere required as a resin material for automobile exterior parts varies depending on each application, but generally -30 ° C or further-
A resin material having an impact strength of 10 kgcm / cm or more under a temperature atmosphere of 40 ° C. has high industrial value because of its high reliability regarding the durability of the material.

Further, the pigment coloring property required for a resin material used in the vehicle field is generally evaluated by its most representative color tone, that is, black coloring property, although it varies depending on the use and the desired hue. In this case, as an evaluation method, the lightness (L *) of a resin molded product to which a certain amount of a coloring agent such as carbon black is added is determined by hue / color difference analysis. A resin material having a smaller L * value has a higher pigment coloring property. It is judged to be excellent. For example, for applications requiring a high degree of design, such as automotive exterior materials such as automobile door handles and wheel covers, for example, the L * value of the resin molded product when carbon black is added by 0.8 parts by weight is 13 or less. A material having excellent jet blackness and transparency is used.

Heretofore, as a method for dealing with such an application in which particularly high impact resistance and pigment coloring property are required, for example, a resin material having high impact resistance is provided with excellent weather resistance and pigment coloring property. A method of laminating materials, a method of coating, a method of coating, and the like are used, but these methods require complicated steps, resulting in high cost, and are not industrially preferable methods.

On the other hand, as a conventional method for improving the impact resistance of a resin material, a resin material in which a rubber component having a low glass transition temperature (Tg) and a low elastic modulus is dispersed in a resin matrix is known.

Further, in order to improve the impact resistance of the resin material in which the rubber component is dispersed, it is possible to utilize polyorganosiloxane having a lower Tg and a lower elastic modulus as the rubber component. JP-A-61-138654.

However, in these methods, a matte-shaped molding appearance defect derived from polyorganosiloxane occurs, and when the rubber graft copolymer to be added has a small particle diameter to improve the molding appearance, impact resistance is improved. Since it is not possible to achieve both high impact resistance and good molding appearance at the same time, the industrial value is low.

Further, in JP-A-1-190746, a vinyl monomer is graft-polymerized to a composite rubber composed of a polyorganosiloxane rubber and a poly (meth) acrylate rubber in order to improve the surface appearance of a resin molded product. A resin composition prepared by blending a graft copolymer with a thermoplastic resin has been proposed.

Further, in Japanese Patent Laid-Open No. 5-279434, as a method for improving the pigment coloring of impact-resistant resin, a vinyl monomer is graft-polymerized on a composite rubber composed of polyorganosiloxane and (meth) acrylate. It has been proposed to use a graft copolymer having a number average particle diameter of 0.01 to 0.07 μm and 20% by volume or less of particles larger than 0.10 μm.

Further, in Japanese Patent Laid-Open No. 62-280210, a graft copolymer composed of a core of crosslinked silicone, a first shell of crosslinked acrylate rubber, and a second shell of a vinyl polymer component is prepared. Resin compositions in combination with a plastic resin have been proposed.

Further, Japanese Patent Laid-Open No. 7-33836 discloses a graft copolymer in which specific polyorganosiloxane fine particles are impregnated with an alkyl (meth) acrylate and then polymerized to form a composite rubber, and a vinyl monomer is graft-polymerized on the composite rubber. A method for producing a polymer has been proposed.

[0013]

However, in JP-A-1-190746, a vinyl-based monomer is added to a composite rubber composed of polyorganosiloxane and polyalkyl (meth) acrylate and having an average particle diameter of 0.08 to 0.6 μm. Regarding the graft copolymer in which the polymer is graft-polymerized, although the ratio of the polyorganosiloxane to the polyalkyl (meth) acrylate and the amount of the graft component in the composite rubber for expressing the impact resistance are mentioned, Describes only a graft copolymer having a graft component amount of 30% by weight and a graft copolymer having a graft component amount of 50% by weight and a polyorganosiloxane content of a composite rubber of 50% by weight. The pigment coloring properties of the graft copolymer and the resin composition containing the graft copolymer are not poor. For its industrial use is low value.

Further, in the method disclosed in Japanese Patent Laid-Open No. 62-280210, there is no description about the pigment coloring property of the graft copolymer and the resin composition containing the graft copolymer, and the silicone rubber in the graft copolymer is not described. Although the amount and the amount of acrylate rubber are mentioned, the ratio of the core made of silicone rubber to the first shell made of acrylate rubber is 48:12 in the examples, The weight fraction of the second shell is described only when it is 40 parts by weight when the total graft copolymer is 100 parts by weight. This graft copolymer and the resin containing the graft copolymer are described. Since the pigment coloring property of the composition is poor, the industrial utility value is low.

In the method of using a graft copolymer proposed in JP-A-5-279434, the number average particle diameter is 0.01 to 0.07 μm and the proportion of particles larger than 0.10 μm is 20% by volume or less. -30 ℃ or-required for automobile exterior parts etc.
Due to its low impact resistance in a low temperature atmosphere of 40 ° C,
Its industrial utility value is low because it can be used for a limited number of purposes.

Further, in the method of Japanese Patent Laid-Open No. 7-33836, the content of polyorganosiloxane in the composite rubber composed of polyorganosiloxane and alkyl (meth) acrylate rubber is mentioned, but the examples are not shown. Only the graft copolymer having a content of 0.29% by weight to 13.5% by weight is described, and the resin composition containing these graft copolymers has low impact resistance under a low temperature atmosphere, and thus is industrially used. Low utility value.

That is, conventionally, in a graft copolymer obtained by graft-polymerizing a vinyl monomer to a composite rubber composed of a polyorganosiloxane and an alkyl (meth) acrylate rubber, and a resin composition containing the graft copolymer, No method has been found for simultaneously satisfying impact resistance in the atmosphere and pigment coloring, and it is possible to satisfy these requirements at the same time and to use it in applications such as automobile exterior parts with particularly high required performance levels. The development of coalescence was strongly desired.

[0018]

The present inventors have found that the polymer structure of polyorganosiloxane constituting the graft copolymer, the polymer composition of the graft copolymer and the impact resistance of the resin composition containing the same in a low temperature atmosphere. As a result of diligent studies on the properties and pigment coloring properties, surprisingly, the crosslinking density of polyorganosiloxane and the amount of polyorganosiloxane in the composite rubber, the amount of alkyl (meth) acrylate rubber, and the amount of graft component in the graft copolymer were By producing by limiting the weight average particle diameter of the graft copolymer, it is possible for the resin composition containing this graft copolymer to exhibit impact resistance and pigment colorability under an unprecedentedly excellent low temperature atmosphere. Heading The invention has been reached.

That is, the gist of the present invention is that
(A) It has a vinyl polymerizable functional group and has a gel content of 60 to
90% by weight, swelling degree measured in toluene solvent is 10
In the composite rubber composed of the polyorganosiloxane of 30 and the (B) alkyl (meth) acrylate rubber,
(C) A graft copolymer obtained by graft-polymerizing at least one monomer selected from an aromatic alkenyl compound, a methacrylic acid ester, an acrylic acid ester and a vinyl cyanide compound, which is a composite rubber ((A) +
(B)) containing 20 to 40% by weight of polysiloxane (A), 60 to 80% by weight of alkyl (meth) acrylate rubber, and 50 to 80% by weight of a graft component (C) based on a graft copolymer. %, And the weight average particle diameter of the graft copolymer is 0.10 to 0.20 μm, and a thermoplastic resin composition containing the same.

The polyorganosiloxane (A) constituting the graft copolymer according to the present invention is produced by adding a crosslinking agent and a vinyl polymerizable functional group-containing siloxane, which is a graft crossing agent, to dimethylsiloxane and condensing it. be able to.

The dimethylsiloxane may be a dimethylsiloxane having a 3- or more-membered ring, preferably a 3- to 6-membered ring. Specific examples include hexamethylcyclotrisiloxane, octamethyltetracyclosiloxane, decamethylpentacyclosiloxane, dodecamethylhexacyclosiloxane, and the like. These may be used alone or as a mixture of two or more.

The vinyl-polymerizable functional group-containing siloxane is not particularly limited as long as it has a vinyl-polymerizable functional group and can be bonded to dimethylsiloxane through a siloxane bond, but the reactivity with dimethylsiloxane is not limited. Considering the above, various alkoxysilane compounds having a vinyl polymerizable functional group are preferable. Specifically, β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane,
Methacryloyloxy such as γ-methacryloyloxypropylmethoxydimethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane and δ-methacryloyloxybutyldiethoxymethylsilane. Examples thereof include siloxane, vinyl siloxane such as tetramethyltetravinylcyclotetrasiloxane, p-vinylphenyldimethoxymethylsilane, and mercaptosiloxane such as γ-mercaptopropyldimethoxymethylsilane and γ-mercaptopropyltrimethoxysilane.

These vinyl-polymerizable functional group-containing siloxanes may be used either individually or as a mixture of two or more, and the amount used is the impact resistance and molding of the resin composition containing the resulting graft copolymer. Considering the appearance, the vinyl-polymerizable functional group-containing siloxane unit is preferably 0.2 to 3 mol%, more preferably 0.3 to 2 mol%, and even more preferably the polyorganosiloxane siloxane unit. It is 0.3 to 1 mol%.

The cross-linking agent is trifunctional or tetrafunctional.
Functional siloxane-based crosslinking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, and tetrabutoxysilane are used.

These cross-linking agents may be used either individually or as a mixture of two or more. The amount of the cross-linking agent used is such that the gel content of the polyorganosiloxane obtained is 60-9.
5% by weight and a swelling degree measured in a toluene solvent of 10
It needs to be adjusted to a range of 30. When the gel content is less than 60% by weight, the graft copolymer containing the polyorganosiloxane and the resin composition containing the same have low impact resistance in a low temperature atmosphere, which is not preferable. When the degree of swelling is less than 10, rubber elasticity is lost due to an increase in the crosslink density of the polyorganosiloxane, and the graft copolymer containing this polyorganosiloxane and the resin composition containing the same are resistant to room temperature. The shock resistance will be low. On the other hand, when the degree of swelling exceeds 30, the impact resistance of the graft copolymer containing the polyorganosiloxane and the resin composition containing the graft copolymer in a low temperature atmosphere becomes low. Considering both the impact resistance at room temperature and the impact resistance in a low temperature atmosphere, the swelling degree of the polyorganosiloxane is more preferably 10 to 20.

The swelling degree according to the present invention is a value which is measured by the following method and serves as an index of the crosslink density of the polyorganosiloxane. The prepared polyorganosiloxane latex is added to about 3 to 5 times the amount of isopropyl alcohol with stirring, and the emulsion is broken and coagulated to obtain a siloxane polymer. The polymer thus obtained is dried under reduced pressure at 80 ° C. for 10 hours. After drying, about 1 g of the polymer is precisely weighed, immersed in about 30 g of toluene, and left at 25 ° C. for 100 hours to swell the toluene in the polymer. Then, the residual toluene was separated and removed by decantation, and the balance was accurately weighed.
After drying under reduced pressure for a period of time, the absorbed toluene is removed by evaporation, and the sample is weighed again. The degree of swelling is calculated by the following equation.

Swelling degree = ((weight of swollen polymer) −
(Dry polymer weight) / (Dry polymer weight) As a method for producing the polyorganosiloxane according to the present invention,
A mixture of the above-mentioned dimethyl siloxane, vinyl-polymerizable functional group-containing siloxane, and cross-linking agent is emulsified with an emulsifier and water, and a homomixer that atomizes the latex by shearing force due to high-speed rotation, or atomization by the jet output from a high-pressure generator. After atomizing using a homogenizer etc.
Polymerization is carried out at a high temperature using an acid catalyst, and then the acid is neutralized with an alkaline substance.

The method of adding the acid catalyst used in the polymerization is as follows.
There are a method of mixing the siloxane mixture with the emulsifier and water, and a method of dropping the latex in which the siloxane mixture is atomized into a high-temperature acid aqueous solution at a constant speed.The method for controlling the particle diameter of the polyorganosiloxane is easy. Considering this, a method is preferred in which a latex in which the siloxane mixture is atomized is dropped at a constant rate into a high-temperature acid aqueous solution.

The emulsifier used in the production of polyorganosiloxane is preferably an anionic emulsifier, and an emulsifier selected from sodium alkylbenzene sulfonate, sodium polyoxyethylene nonylphenyl ether sulfate, etc. is used. Particularly, sulfonic acid emulsifiers such as sodium alkylbenzene sulfonate and sodium lauryl sulfonate are preferable.

These emulsifiers are based on the siloxane mixture 10
It is used in the range of about 0.05 to 5 parts by weight with respect to 0 parts by weight. When the amount used is small, the dispersion state becomes unstable, and it becomes impossible to maintain the emulsified state with a fine particle size. On the other hand, if the amount is too large, coloring of the resin composition molded article caused by the emulsifier becomes excessively disadvantageous.

Examples of the acid catalyst used for the polymerization of polyorganosiloxane include sulfonic acids such as aliphatic sulfonic acid, aliphatic substituted benzenesulfonic acid and aliphatic substituted naphthalenesulfonic acid, and mineral acids such as sulfuric acid, hydrochloric acid and nitric acid. . These acid catalysts are used alone or in combination of two or more. Among these, aliphatic-substituted benzenesulfonic acid is preferable, and n-dodecylbenzenesulfonic acid is particularly preferable, because it is also excellent in stabilizing the polyorganosiloxane latex. The amount of the acid catalyst used in the production of the polyorganosiloxane is not particularly limited, but is considered in consideration of the pigment coloring property and the low-temperature impact property of the obtained graft copolymer and the resin composition containing the same. Siloxane mixture 100
The amount is preferably 0.5 to 10 parts by weight, more preferably 1 to 5 parts by weight, even more preferably 1 to 3 parts by weight with respect to parts by weight.

The polymerization temperature of the polyorganosiloxane is 5
The temperature is preferably 0 ° C or higher, more preferably 80 ° C or higher.

Further, after the polyorganosiloxane is polymerized at a high temperature, the polyorganosiloxane is allowed to stand at a temperature equal to or lower than the polymerization temperature, whereby the crosslinking reaction of the polyorganosiloxane proceeds, the gel content of the obtained polyorganosiloxane increases, and The degree of swelling in the toluene solvent decreases. The polymerization reaction and the crosslinking reaction can be stopped by cooling the reaction solution and then neutralizing the polymerization latex with an alkaline substance such as sodium hydroxide, sodium hydroxide, and sodium carbonate.

The time of the polymerization reaction is 2 hours or more, more preferably 5 hours or more when the acid catalyst is mixed with the siloxane mixture, the emulsifier and water to be finely divided and polymerized, and the siloxane is added to the aqueous solution of the acid catalyst. In the method of dropping the latex in which the mixture is atomized, it is preferable to keep the mixture for 1 hour or more after the dropping of the latex.

The time after which the latex after polymerization is left at a temperature not higher than the polymerization temperature is such that the polyorganosiloxane obtained has a gel content of 60 to 95% by weight and a swelling degree measured in a toluene solvent of 10 to 30. However, this standing time is appropriately selected depending on the amount of the crosslinking agent used.

The size of the polyorganosiloxane particles is
The weight average particle diameter of the graft copolymer using the polyorganosiloxane is not particularly limited as long as it is in the range of 0.10 μm to 0.20 μm, but the weight average particle diameter is preferably 0.05 to 0. It is in the range of 0.13 μm.

The polyorganosiloxane latex thus produced is impregnated with an alkyl (meth) acrylate component composed of an alkyl (meth) acrylate and a polyfunctional alkyl (meth) acrylate, and then polymerized to form a composite rubber. Obtainable.

As the alkyl (meth) acrylate,
For example, methyl acrylate, ethyl acrylate, n-
Examples thereof include alkyl acrylates such as propyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate, and alkyl methacrylates such as hexyl methacrylate, 2-ethylhexyl methacrylate, and n-lauryl methacrylate. The use of n-butyl acrylate is particularly preferable. Examples of polyfunctional alkyl (meth) acrylates include allyl methacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, triallyl cyanurate, triallyl isocyanate. Nurate and the like are included. The amount of the polyfunctional alkyl (meth) acrylate used is 0.1 to 20% by weight in the alkyl (meth) acrylate component, preferably 0.2 to.
1% by weight.

The alkyl (meth) acrylate and polyfunctional alkyl (meth) acrylate may be used alone or in combination of two or more.

The composite rubber comprising the polyorganosiloxane and the alkyl (meth) acrylate rubber according to the present invention is
It can be produced by adding the above-mentioned alkyl (meth) acrylate component to the latex of the polyorganosiloxane component and polymerizing it by the action of a usual radical polymerization initiator. As a method of adding the alkyl (meth) acrylate, there are a method of mixing with the latex of the polyorganosiloxane component at once and a method of dropping it into the latex of the polyorganosiloxane component at a constant rate. Considering the impact resistance of the resulting graft copolymer and the resin composition containing the same, a method of mixing the latex of the polyorganosiloxane component at once is preferable. As the radical polymerization initiator used for the polymerization, a peroxide, an azo type initiator or a redox type initiator in which an oxidizing agent and a reducing agent are combined is used. Among these, a redox type initiator is preferable, and a sulfoxylate type initiator in which ferrous sulfate / ethylenediaminetetraacetic acid disodium salt / longalide / hydroperoxide is combined is particularly preferable.

In the composite rubber comprising the polyorganosiloxane and the alkyl (meth) acrylate rubber according to the present invention, the amount of polyorganosiloxane is 20 to 40% by weight and the amount of alkyl (meth) acrylate rubber is 60 to 8.
0% by weight. When the amount of polyorganosiloxane in the composite rubber is less than 20% by weight, the resulting graft copolymer and the resin composition containing the same have low impact resistance under a low temperature atmosphere because the content of polyorganosiloxane is small. If it exceeds 40% by weight, the pigment copolymer and the resin composition containing the same have poor pigment colorability and low industrial value. In consideration of both the impact resistance of the graft copolymer and the resin composition containing the same in a low temperature atmosphere and the pigment coloring property, the amount of the polyorganosiloxane in the composite rubber is preferably 22 to 35% by weight, The amount of the alkyl (meth) acrylate rubber is 65 to 78% by weight, more preferably 25 to 30% by weight of the polyorganosiloxane in the composite rubber, and the amount of the alkyl (meth) acrylate rubber is 70 to 7%.
5% by weight.

The graft copolymer according to the present invention comprises a composite rubber produced by emulsion polymerization as described above, and at least one monomer selected from aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters and vinyl cyanide compounds. It can be produced by graft polymerization of the body. Among the monomers used for the graft polymerization, the aromatic alkenyl compound is, for example, styrene, α-methylstyrene, vinyltoluene, etc., and the methacrylic acid ester is, for example, methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, etc.
The acrylic ester is, for example, methyl acrylate, ethyl acrylate, butyl acrylate and the like, and the vinyl cyanide compound is, for example, acrylonitrile, methacrylonitrile and the like. Of these, considering the compatibility between the graft copolymer and a copolymer obtained from an aromatic alkenyl compound and a vinyl cyanide compound described later, the monomer used in the graft polymerization is an aromatic alkenyl compound and an acyan compound. A vinyl chloride compound is preferred, and a mixture of styrene and acrylonitrile is more preferred.

In the graft polymerization, at least one monomer selected from an aromatic alkenyl compound, a methacrylic acid ester, an acrylic acid ester and a vinyl cyanide compound is added to a latex of a composite rubber, and it is subjected to a radical polymerization technique in one step or in a multi-step manner. Polymerization can be carried out with
Considering the impact resistance and pigment coloring of the resulting graft copolymer and the resin composition containing the same, it is preferable to carry out the polymerization in two or more stages.

Further, various chain transfer agents for adjusting the molecular weight and graft ratio of the graft copolymer can be added to the monomers used in the graft polymerization.

In the graft copolymer according to the present invention, the amount of the graft polymerization component obtained by graft polymerization of at least one monomer selected from aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters and vinyl cyanide compounds is , 50 to 80% by weight based on all graft copolymers
It is. If the graft polymerization component is less than 50% by weight, the pigment coloring property of the graft copolymer and the resin composition containing it will be poor, and if it exceeds 80% by weight, the amount of rubber will be low and the impact resistance will be low, such being undesirable. In consideration of both impact resistance and pigment coloring of the graft copolymer and the resin composition containing the same, the aromatic alkenyl compound, the methacrylic acid ester, the acrylic acid ester and the vinyl cyanide compound in the graft copolymer are considered. The amount of the graft polymerization component obtained by graft polymerization of at least one selected monomer is preferably 50 to 7 based on the total graft copolymer.
0% by weight, more preferably 50 to 60% by weight.

The weight average particle diameter of the graft copolymer according to the present invention is 0.10 to 0.20 μm, and is 0.10 μm.
If less than 0.20 μm, the impact resistance of the resin composition containing the graft copolymer in a low temperature atmosphere becomes low, and if it exceeds 0.20 μm, the pigment coloring property of the resin composition containing the graft copolymer is poor. Low industrial value. Considering both the impact resistance of the resin composition containing the graft copolymer in a low temperature atmosphere and the pigment coloring property, it is more preferable that the weight average particle diameter of the graft copolymer is 0.10 to 0.15 μm. preferable.

The graft copolymer according to the present invention is prepared by adding the graft copolymer latex produced as described above to hot water in which a metal salt such as calcium chloride, calcium acetate or aluminum sulfate is dissolved, and salting out and coagulating. By doing so, the graft copolymer can be separated and recovered.

In the present invention, the above graft copolymer further includes a copolymer obtained from at least one selected from aromatic alkenyl compounds, vinyl cyanide compounds and vinyl monomers copolymerizable therewith. Can be blended.

The aromatic alkenyl compound is, for example, styrene, α-methylstyrene, vinyltoluene, monochlorostyrene, dichlorostyrene, monobromostyrene, p-tert-butylstyrene, ethylstyrene, vinylnaphthalene, etc., and preferably styrene,
It is α-methylstyrene. Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile, and acrylonitrile is preferable.
Examples of the copolymerizable vinyl monomer include methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate and glycidyl methacrylate, acrylic acid esters such as methyl acrylate, ethyl acrylate and butyl acrylate, and N.
Examples include maleimide compounds such as -phenylmaleimide and N-methylmaleimide, and maleic anhydride.

Preferred examples of the copolymer include a styrene-acrylonitrile copolymer (SAN resin) and a styrene-acrylonitrile-N-phenylmaleimide copolymer.

As the method for producing the copolymer, generally known methods such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization are used.

The amount of addition can be arbitrarily selected for the graft copolymer.

The graft copolymer and the thermoplastic resin composition of the present invention can be extruded and molded by a commonly known kneading machine. Examples of the molding machine used for kneading include an extruder, an injection molding machine, a blow molding machine, a calender molding machine, and an inflation molding machine.

Further, the graft copolymer and the thermoplastic resin composition of the present invention may contain, if necessary, dyes, pigments, stabilizers, reinforcing agents, fillers, flame retardants and the like.

[0055]

EXAMPLES The present invention will be described below with reference to examples. In addition,
In the Reference Examples, Examples and Comparative Examples, "parts" and "%" are "parts by weight" and "% by weight" unless otherwise specified.
Means

The weight average particle diameters of the polyorganosiloxane in the latex in the reference example and the graft copolymer in the example are DLS-700 manufactured by Otsuka Electronics Co., Ltd.
It was determined by a dynamic light scattering method using a mold.

The measurement of Izod impact strength in Examples and Comparative Examples was carried out by the method according to ASTM D258, and the measurement of Izod impact strength particularly in a low temperature atmosphere was carried out for 12 hours or more in an atmosphere of -30 ° C or -40 ° C. The measurement was performed after leaving the Izod test piece to stand.

The surface hardness (Rockwell hardness) in the examples and comparative examples was measured by the method according to ASTM D785.

In addition, the pigment coloring properties of the resin compositions in Examples and Comparative Examples were evaluated using an injection molding machine IS-100EN manufactured by Toshiba Machine Co., Ltd. 100 mm * 10.
It was performed by a hue measurement of a 0 mm * 3 mm plate in accordance with JIS Z8729.

Reference Example 1 Production of Polyorganosiloxane Latex L-1 96 parts of octamethyltetracyclosiloxane, 2 parts of γ-methacryloyloxypropyldimethoxymethylsilane and 2 parts of ethyl orthosilicate were mixed to obtain 100 parts of a siloxane mixture. Got 300 ml of distilled water containing 0.67 parts of sodium dodecylbenzenesulfonate dissolved therein.
And 10,000 parts / min with a homomixer.
After stirring for 300 minutes, add 300 kg / cm ^{2 to the} homogenizer.
Once to obtain a stable premixed organosiloxane latex.

On the other hand, 2 parts of dodecylbenzenesulfonic acid and 98 parts of distilled water were injected into a reactor equipped with a reagent injection container, a cooling tube, a jacket heater and a stirring device, and 2% by weight of dodecylbenzenesulfonic acid was added. An aqueous solution was prepared.

With this aqueous solution heated to 85 ° C., the premixed organosiloxane latex was added dropwise over 4 hours, and the temperature was maintained and cooled for 1 hour after the completion of the addition. The reaction solution was left at room temperature for 48 hours, and then neutralized with an aqueous solution of sodium hydroxide.

The latex (L-
When 1) was dried at 170 ° C. for 30 minutes to obtain a solid content, it was 17.3%. The weight average particle diameter of the polyorganosiloxane in the latex was 0.08 μm. Also, the gel content of polyorganosiloxane is 8
The swelling degree measured in a 5% toluene solvent was 14.5.

Reference Example 2 Polyorganosiloxane L-
Preparation of 2 95 parts of octamethyltetracyclosiloxane, 2 parts of γ-methacryloyloxypropyldimethoxymethylsilane and 3 parts of ethyl orthosilicate were mixed to obtain 100 parts of a siloxane-based mixture. 300 ml of distilled water containing 0.67 parts of sodium dodecylbenzenesulfonate dissolved therein.
And 10,000 parts / min with a homomixer.
After stirring for 300 minutes, add 300 kg / cm ^{2 to the} homogenizer.
Once to obtain a stable premixed organosiloxane latex.

On the other hand, 2 parts of dodecylbenzenesulfonic acid and 98 parts of distilled water were injected into a reactor equipped with a reagent injection container, a cooling pipe, a jacket heater and a stirrer.
An aqueous solution of dodecylbenzenesulfonic acid was prepared.

With the aqueous solution heated to 85 ° C., the premixed organosiloxane latex was added dropwise over 4 hours, and the temperature was maintained and cooled for 1 hour after the completion of the addition. After the temperature of the reaction solution dropped to 40 ° C., the reaction solution was neutralized with a caustic soda aqueous solution.

The latex (L-
The solid content of 2) was 17.7%, and the weight average particle diameter of the polyorganosiloxane in the latex was 0.08 μm. Also, the gel content of polyorganosiloxane is 80
%, The swelling degree measured in a toluene solvent was 17.7.

Reference Example 3 Polyorganosiloxane L-
Preparation of 3 Latex (L-3) was prepared in the same manner as in Reference Example 1 except that the siloxane mixture in Reference Example 1 was changed to 98 parts of octamethyltetracyclosiloxane and 2 parts of γ-methacryloyloxypropyldimethoxymethylsilane. . The solid content of the obtained polyorganosiloxane latex was 17.5%, and the weight average particle diameter was 0.08 μm. The polyorganosiloxane was soluble in the toluene solvent, and no gel component was observed.

Reference Example 4 Polyorganosiloxane L-
Preparation of 4 Latex (L) in the same manner as in Reference Example 1 except that the siloxane-based mixture in Reference Example 1 was changed to 93 parts octamethyltetracyclosiloxane, 2 parts γ-methacryloyloxypropyldimethoxymethylsilane and 5 parts ethyl orthosilicate. -4) was prepared. The solid content of the obtained polyorganosiloxane latex was 17.5%, and the weight average particle diameter was 0.08 μm. The gel content of the polyorganosiloxane was 95%, and the degree of swelling measured in a toluene solvent was 7.0.

Reference Example 5 Polyorganosiloxane L-
Production of 5 Polyorganosiloxane latex (L-5) was prepared in the same manner as in Reference Example 1 except that the amount of dodecylbenzenesulfonic acid used was changed to 10 parts. The solid content of the obtained polyorganosiloxane latex was 17.5%, and the weight average particle diameter was 0.05 μm. Also, the gel content of polyorganosiloxane is 10
%, The swelling degree measured in a toluene solvent was 25.0.

Reference Example 6 Polyorganosiloxane L-
Preparation of 6 96 parts of octamethyltetracyclosiloxane, 2 parts of γ-methacryloyloxypropyldimethoxymethylsilane and 2 parts of ethyl orthosilicate were mixed to obtain 100 parts of a siloxane-based mixture. To this was added 200 parts of distilled water in which 0.67 part of sodium dodecylbenzenesulfonate and 0.67 part of dodecylbenzenesulfonic acid were dissolved, and the mixture was stirred with a homomixer at 10,000 rpm for 2 minutes. One pass at a pressure of ² cm ² resulted in a stable premixed organosiloxane latex. This organosiloxane latex was transferred into a reactor equipped with a condenser, a jacket heater and a stirrer, heated at 85 ° C. for 5 hours while stirring and mixing, and then cooled. The reaction solution was left at room temperature for 48 hours, and then neutralized with an aqueous solution of sodium hydroxide. The solid content of the obtained polyorganosiloxane latex (L-6) was 29.0%, and the weight average particle diameter was 0.19 μm. The gel content of the polyorganosiloxane was 95%, and the degree of swelling measured in a toluene solvent was 7.0.

Table 1 shows the preparation conditions and the results of the polyorganosiloxane of the above reference example.

[0073]

[Table 1]

Example 1 Preparation of Graft Copolymer S-1 A polyorganosiloxane latex (reference example 1) was placed in a reactor equipped with a reagent injection container, a cooling tube, a jacket heater and a stirrer. L-1) 119.5 parts and sodium polyoxyethylene alkylphenyl ether sulfate (Emal NC-35 manufactured by Kao Co., Ltd.) 0.8 parts were collected and added with 203 parts of distilled water and mixed, and then n-butyl acrylate. 53.2 parts, allyl methacrylate 0.21 parts,
1,3-butylene glycol dimethacrylate 0.11
Parts and 0.13 parts of tertiary butyl hydroperoxide were added.

By passing a nitrogen stream through this reactor, the atmosphere was replaced with nitrogen, and the temperature was raised to 60.degree. When the internal liquid temperature reaches 60 ° C., ferrous sulfate 0.00
01 parts, ethylenediaminetetraacetic acid disodium salt 0.0
An aqueous solution obtained by dissolving 003 parts and 0.24 parts of Rongalit in 10 parts of distilled water was added to start radical polymerization. The liquid temperature rose to 78 ° C. due to the polymerization of the acrylate component. This state was maintained for 1 hour to complete the polymerization of the acrylate component, thereby obtaining a composite rubber latex of polyorganosiloxane and butyl acrylate rubber.

After the liquid temperature inside the reactor dropped to 60 ° C.,
An aqueous solution prepared by dissolving 0.4 parts of Rongalit in 10 parts of distilled water was added, and then a mixed solution of 11.1 parts of acrylonitrile, 33.2 parts of styrene and 0.2 parts of tert-butyl hydroperoxide was added for about 1 hour. It was dropped and polymerized. After holding for 1 hour after the completion of the dropwise addition, ferrous sulfate was added to a solution containing 0.1 mg of ferrous sulfate.
An aqueous solution prepared by dissolving 0002 parts, 0.0006 parts of ethylenediaminetetraacetic acid disodium salt and 0.25 part of Rongalit in 10 parts of distilled water was added, and then 7.4 parts of acrylonitrile, 22.2 parts of styrene and tertiary butyl hydro. A mixed solution of 0.1 part of peroxide was added dropwise over about 40 minutes to carry out polymerization. After the completion of dropping, the mixture was maintained for 1 hour and then cooled to obtain a latex of a graft copolymer obtained by graft-polymerizing acrylonitrile and styrene onto a composite rubber composed of polyorganosiloxane and butyl acrylate rubber. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.13 μm.

Then, 150 parts of an aqueous solution in which aluminum sulfate was dissolved at a ratio of 7.5% was heated to 60 ° C. and stirred. 100 parts of the latex of the graft copolymer was gradually dropped into this, and solidified. Next, the precipitate was separated, washed and dried to obtain a graft copolymer (S-1).

48 parts of this graft copolymer and a mixture of acrylonitrile-styrene copolymer (abbreviated as SAN-1, 70 parts of styrene and 30 parts of acrylonitrile) prepared by the suspension polymerization method were polymerized by suspension polymerization to give dimethyl. 52 parts of reduced viscosity (ηsp / c) of 0.60 measured in formamide solution (25 ° C.) and 0.3 part of phosphite antioxidant Adecastable C (manufactured by Asahi Denka Co., Ltd.) as an auxiliary agent , Barium stearate 0.4
Parts and 0.4 parts of ethylenebisstearylamide are mixed using a Henschel mixer, and the mixture is heated to 230 ° C.
The mixture was fed to a degassing extruder heated to 1, and kneaded to give a post-strand shape, which was cut with a cutter to obtain pellets of the mixed resin composition. The obtained pellets were molded into a test piece by an injection molding machine in which the cylinder temperature was 230 ° C and the mold temperature was 60 ° C. Using this test piece, Izod impact strength and Rockwell hardness were measured under normal temperature and low temperature atmosphere.

The Izod impact strength at 23 ° C. of 1/4 ″ thickness is 38.0 kgcm / cm, and the Izod impact strength under −30 ° C. atmosphere is 15.6 kgcm / cm, −
Izod impact strength in an atmosphere of 40 ° C is 10.6k
gcm / cm and Rockwell hardness (R scale)
Was 95.2.

Then, 48 parts of the graft copolymer and S
AN-1 52 parts Further, phosphite type antioxidant Adecastable C (manufactured by Asahi Denka Co., Ltd.) 0.3 as an auxiliary agent
Parts, 0.4 parts of barium stearate, 0.4 parts of ethylenebisstearylamide and 0.8 parts of carbon black (CB-960 manufactured by Mitsubishi Chemical Corporation) were mixed using a Henschel mixer, and this mixture was mixed with 230 parts. The pellets of the mixed resin composition were obtained by supplying the mixture to a degassing extruder heated to ℃, kneading and shaping it into a strand, and then cutting this with a cutter. Cylinder temperature of the obtained pellets 2
A plate having a size of 100 mm * 100 mm * 3 mm was molded by an injection molding machine set at 30 ° C. and a mold temperature of 60 ° C.
The appearance of the obtained molded plate was very good with high gloss. Moreover, when the hue of the molded plate was measured,
* Indicates a pigment coloring property with low brightness of 12 and jet blackness.

Table 2 shows the above evaluation results.

[0082]

[Table 2]

Example 2 Production of Graft Copolymer S-2 Using the polyorganosiloxane latex (L-2) obtained in Reference Example 2, the same composite rubber reaction and graft copolymerization as in Example 1 were carried out. Polymer preparation was carried out. The weight average particle size of the graft copolymer in the obtained latex is
It was 0.13 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 38.6 kgcm / c
m, Izod impact strength at -30 ℃, 15.3kg
Izod impact strength at 10 cm / cm and -40 ° C is 10.
The 7 kgcm / cm and Rockwell hardness (R scale) was 95.3. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. The appearance of the obtained molded plate was very good with high gloss. Further, when the hue of the molded plate was measured, L * was 12, which was low in lightness and high in jet black, and showed good pigment colorability.

Table 2 shows the above evaluation results.

Comparative Example 1 Production of Graft Copolymer T-1 Using the polyorganosiloxane latex (L-3) obtained in Reference Example 3, the same composite rubber reaction and graft copolymerization as in Example 1 were carried out. Polymer preparation was carried out. The weight average particle size of the graft copolymer in the obtained latex is
It was 0.13 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 37.6 kgcm / c
m, Izod impact strength at -30 ℃, 9.1kgc
Izod impact strength at m / cm and -40 ° C is 5.0k
gcm / cm and Rockwell hardness (R scale)
Was 95.2. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L
* Was 12.

Table 2 shows the above evaluation results.

Comparative Example 2 Preparation of Graft Copolymer T-2 Using the polyorganosiloxane latex (L-4) obtained in Reference Example 4, the same composite rubber reaction and graft copolymerization as in Example 1 were carried out. Polymer preparation was carried out. The weight average particle size of the graft copolymer in the obtained latex is
It was 0.13 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 25.1 kgcm / c
m, Izod impact strength at -30 ℃, 8.7kgc
Izod impact strength at m / cm and -40 ° C is 4.3k
gcm / cm and Rockwell hardness (R scale)
Was 95.4. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L
* Was 12.

Table 2 shows the above evaluation results.

Comparative Example 3 Production of Graft Copolymer T-3 Using the polyorganosiloxane latex (L-5) obtained in Reference Example 5, the same composite rubber reaction and graft copolymerization as in Example 1 were carried out. Polymer preparation was carried out. The weight average particle size of the graft copolymer in the obtained latex is
It was 0.08 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 25.3 kgcm / c
m, Izod impact strength at -30 ℃, 6.1kgc
Izod impact strength at m / cm and -40 ° C is 4.0k
gcm / cm and Rockwell hardness (R scale)
Was 94.3. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L
* Was 11.

Comparative Example 4 Preparation of Graft Copolymer T-4 The polyorganosiloxane latex charged in the reactor in Example 1 was changed to L-6 prepared in Reference Example 6, and this polyorganosiloxane was further prepared. Latex (L
-6) was charged to 71.3 parts and distilled water to 251.
A graft copolymer was produced in the same manner as in Example 1 except that the amount was changed to 2 parts. The weight average particle diameter of the graft copolymer in the obtained latex was 0.25 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 32.2 kgcm / c
m, Izod impact strength at -30 ℃, 14.6kg
Izod impact strength at 10 cm / cm and -40 ° C is 10.
The 1 kgcm / cm and Rockwell hardness (R scale) was 96.0. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L * was 16.

Table 2 shows the above evaluation results.

(Comparative Example 5) Production of Graft Copolymer T-5 A polyorganosiloxane latex obtained in Reference Example 1 was placed in a reactor equipped with a reagent injection container, a cooling tube, a jacket heater and a stirrer. 16 parts of L-1) and 0.8 parts of sodium polyoxyethylene alkylphenyl ether sulfate (Emal NC-35 manufactured by Kao Co., Ltd.) were collected and mixed with 163.4 parts of distilled water, and then n- Butyl acrylate 74.4 parts, allyl methacrylate 0.30
Part, 1,3-butylene glycol dimethacrylate 0.
A mixture of 15 parts and 0.19 parts of tertiary butyl hydroperoxide was added.

By passing a nitrogen stream through this reactor, the atmosphere was replaced with nitrogen, and the temperature was raised to 60.degree. When the internal liquid temperature reaches 60 ° C., ferrous sulfate 0.00
01 parts, ethylenediaminetetraacetic acid disodium salt 0.0
An aqueous solution obtained by dissolving 003 parts and 0.24 parts of Rongalit in 10 parts of distilled water was added to start radical polymerization. The liquid temperature rose to 82 ° C. due to the polymerization of the acrylate component. This state was maintained for 1 hour to complete the polymerization of the acrylate component, thereby obtaining a composite rubber latex of polyorganosiloxane and butyl acrylate rubber.

After the liquid temperature inside the reactor dropped to 60 ° C.,
An aqueous solution prepared by dissolving 0.4 parts of Rongalit in 10 parts of distilled water was added, and then a mixed solution of 7.4 parts of acrylonitrile, 22.1 parts of styrene and 0.13 parts of tertiary butyl hydroperoxide was added for about 40 minutes. It was dropped and polymerized. After holding for 1 hour after completion of dropping, an aqueous solution prepared by dissolving 0.0002 parts of ferrous sulfate, 0.0006 parts of ethylenediaminetetraacetic acid disodium salt and 0.25 parts of Rongalit in 10 parts of distilled water was added, and then acrylonitrile. A mixed solution of 3.7 parts, 11.1 parts of styrene and 0.1 part of tert-butyl hydroperoxide was added dropwise over about 10 minutes to carry out polymerization. After the completion of dropping, the mixture was maintained for 1 hour and then cooled to obtain a latex of a graft copolymer in which acrylonitrile and styrene were graft-polymerized to a composite rubber composed of polyorganosiloxane and butyl acrylate rubber. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method is 0.11 μm.
Met.

Next, 150 parts of an aqueous solution in which aluminum sulfate was dissolved in a ratio of 7.5% was heated to 60 ° C. and stirred. 100 parts of the latex of the graft copolymer was gradually dropped into this, and solidified. Next, the precipitate was separated, washed and dried to obtain a graft copolymer (T-5).

34.3 parts of this graft copolymer and S
AN-1 65.7 parts Further as a auxiliary phosphite antioxidant Adecastable C (manufactured by Asahi Denka Co., Ltd.)
0.3 parts, barium stearate 0.4 parts and ethylenebisstearylamide 0.4 parts were mixed using a Henschel mixer, and this mixture was supplied to a degassing extruder heated to 230 ° C. and kneaded. Then, the mixture was shaped into a post-strand and cut with a cutter to obtain pellets of the mixed resin composition. Cylinder temperature 23
A test piece was molded by an injection molding machine set at 0 ° C and a mold temperature of 60 ° C. Using this test piece, Izod impact strength and Rockwell hardness were measured under normal temperature and low temperature atmosphere.

The Izod impact strength at 1/4 "thickness at 23 ° C was 32.1 kgcm / cm, and the Izod impact strength at -30 ° C was 14.2 kgcm / cm,-
Izod impact strength at 40 ° C is 8.4kg
cm / cm and Rockwell hardness (R scale)
It was 95.2.

Next, 34.3 parts of graft copolymer part and 65.7 parts of SAN-1 were further added, and 0.3 part of phosphite antioxidant Adecastable C (manufactured by Asahi Denka Co., Ltd.) as an auxiliary agent, stearin. 0.4 parts of barium acid, 0.4 parts of ethylenebisstearylamide and 0.8 parts of carbon black (CB-960 manufactured by Mitsubishi Chemical Corporation) were mixed using a Henschel mixer, and this mixture was heated to 230 ° C.
The mixture was fed to a degassing extruder heated to 1, and kneaded to give a post-strand shape, which was cut with a cutter to obtain pellets of the mixed resin composition. The obtained pellets were molded into a plate having dimensions of 100 mm × 100 mm × 3 mm by an injection molding machine in which the cylinder temperature was 230 ° C. and the mold temperature was 60 ° C. Moreover, when the hue of the molded plate was measured,
* Was 15.

Table 2 shows the above evaluation results.

Comparative Example 6 Production of Graft Copolymer T-6 In Example 1, the amount of polyorganosiloxane latex (L-1) charged into the reactor was 59.8 parts, and the amount of distilled water was 252. 6 parts of n-butyl acrylate in 3 parts
3.5 parts, 0.25 parts allyl methacrylate, 1,3
-0.13 parts of butylene glycol dimethacrylate and 0,3 parts of tertiary butyl hydroperoxide.
A graft copolymer (T-6) was produced in the same manner as in Example 1 except that the amount was changed to 16 parts. The weight average particle size of the graft copolymer in the latex determined by the dynamic light scattering method was 0.15 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 36.4 kgcm / c
m, Izod impact strength at -30 ℃, 8.5kgc
Izod impact strength at m / cm and -40 ° C is 5.1k
gcm / cm and Rockwell hardness (R scale)
Was 95.1. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L
* Was 11.

Table 2 shows the above evaluation results.

Comparative Example 7 Preparation of Graft Copolymer T-7 In Example 1, the amount of polyorganosiloxane latex (L-1) charged in the reactor was 192.1 parts, and the amount of distilled water was 142 parts. .9 parts to 4 parts of n-butyl acrylate
0.6 parts, allyl methacrylate 0.16 parts, 1,3
-0.08 part of butylene glycol dimethacrylate and 0. 8 parts of tertiary butyl hydroperoxide.
A graft copolymer (T-7) was produced in the same manner as in Example 1 except that the amount was changed to 10 parts. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.11 μm.

Then, the obtained graft copolymer and S
A mixture of AN-1 was extruded and molded to obtain a test piece. 2
Izod impact strength at 3 ° C is 27.8 kgcm / c
m, Izod impact strength at -30 ℃, 13.8kg
Izod impact strength at -40 ° C in cm / cm is 9.8.
kgcm / cm and Rockwell hardness (R scale)
Was 94.7. Further, as in Example 1, carbon black was added and extrusion / molding was carried out to obtain a molded plate for evaluating pigment colorability. When the hue of the molded plate was measured, L
* Was 15.

Table 2 shows the above evaluation results.

From the examples and comparative examples, the following facts have become clear.

1) The resin compositions containing the graft copolymers of Examples 1 and 2 showed high Izod impact strength at room temperature and had a pressure of 10 kgcm / cm or more even under a low temperature atmosphere of -30 ° C and -40 ° C. It has an impact strength suitable as a material for automobile exterior parts, and has a low L * value of a black colored plate, and simultaneously satisfies the excellent pigment colorability that can be used without painting.

2) Since the resin composition containing the graft copolymer of Comparative Example 1 uses the polyorganosiloxane having no cross-linking structure as the composite rubber, the Izod impact strength at room temperature and the pigment coloring property are Although excellent, it has a low Izod impact strength in a low temperature atmosphere of −30 ° C. and −40 ° C., and therefore cannot be used in applications requiring high impact resistance in a low temperature atmosphere such as automobile exterior parts. Absent.

3) Since the resin composition containing the graft copolymer of Comparative Example 2 has a high crosslink density with a swelling degree of less than 10 measured in a toluene solvent and contains a rigid polyorganosiloxane in the composite rubber, Also, the Izod impact strength in a low temperature atmosphere is low, which is not preferable as an industrial material.

4) Since the resin composition containing the graft copolymer of Comparative Example 3 contains the graft copolymer having a small average particle diameter of 0.08 μm in weight average particle diameter, Izod impact strength is low, which is not preferable.

5) Since the resin composition containing the graft copolymer of Comparative Example 4 contains the graft copolymer having a large average particle diameter of 0.25 μm in weight average particle diameter, L of the black colored plate was obtained. * The value is high, and it cannot be used for applications requiring a high degree of pigment coloring, such as when an automobile exterior part is used without painting.

6) Since the resin composition containing the graft copolymer of Comparative Example 5 uses a graft copolymer having a small graft component amount of 30 parts, the pigment coloring property is poor.

7) Since the resin composition containing the graft copolymer of Comparative Example 6 uses the graft copolymer having a polyorganosiloxane content of less than 20% in the composite rubber, the pigment coloring property is excellent. However, -30 ° C and -4
Since the Izod impact strength in a low temperature atmosphere such as 0 ° C. is low, it cannot be used in applications requiring impact resistance in a high temperature atmosphere such as automobile exterior parts, which is not preferable.

8) Since the resin composition containing the graft copolymer of Comparative Example 7 uses the graft copolymer in which the polyorganosiloxane content in the composite rubber exceeds 40%,
Since the black colored plate has a high L * value, it cannot be used in applications where a high degree of pigment coloring is required, such as when an automobile exterior part is used without coating.

[0120]

As described above, the present invention has the following remarkable effects, and its industrial value is extremely large.

1) The graft copolymer according to the present invention and the resin composition containing the graft copolymer are excellent in impact resistance, particularly impact resistance in a low temperature atmosphere, surface hardness and pigment colorability.

2) Particularly, the balance between Izod impact strength and pigment colorability under a low temperature atmosphere cannot be obtained by a resin composition using a conventionally known composite rubber composed of polyorganosiloxane and acrylate rubber as a rubber source. This is a very high level, and its utility value as various industrial materials, especially materials for automobile exterior parts, is extremely high.

Claims (2)

[Claims] 1. A polyorganosiloxane having (A) a vinyl-polymerizable functional group, a gel content of 60 to 95% by weight, and a swelling degree measured in a toluene solvent of 10 to 30 and an alkyl (B). Graft copolymer in which at least one monomer selected from (C) aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester or vinyl cyanide compound is graft-polymerized to a composite rubber composed of (meth) acrylate rubber And the polyorganosiloxane (A) in the composite rubber ((A) + (B))
Content of 20 to 40% by weight, an alkyl (meth) acrylate rubber (B) of 60 to 80% by weight, and a content of a graft component (C) based on the graft copolymer of 50 to 80%.
%, And the weight average particle diameter of the graft copolymer is 0.10 to 0.20 μm. 2. The graft copolymer according to claim 1, and a copolymer obtained from at least one selected from an aromatic alkenyl compound, a vinyl cyanide compound and a vinyl monomer copolymerizable therewith. Thermoplastic resin composition.