JP3359530B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an impact resistance containing a graft copolymer excellent in the stability and productivity of a polymerized latex at the time of production, excellent in heat stability, weather resistance and pigment coloring. The present invention relates to a thermoplastic resin composition.

[0002]

2. Description of the Related Art Improving the impact resistance of a resin material is extremely useful for industrial applications, such as not only expanding the application of the material but also making it possible to reduce the thickness of the molded product and increase its size. Large and various proposals have been made so far. Especially Tg
A resin material in which a rubber component having a low modulus of elasticity is dispersed in a resin matrix has been commercialized because of its excellent impact resistance.

In order to further improve the impact resistance of a resin material in which such a rubber component is dispersed, a method of utilizing a polyorganosiloxane having a lower Tg and a lower elastic modulus as a rubber component is disclosed in Japanese Patent Application Laid-Open No. 60-252613. It is proposed in the gazette. However, in this method, a mat-like molded appearance defect derived from polyorganosiloxane occurs, and if the particle size of the graft rubber is reduced to improve the molded appearance, the impact resistance is reduced. It was difficult to achieve both good properties and good molded appearance.

[0004] Japanese Patent Publication No. 8-30102 discloses a graft obtained by graft-polymerizing a vinyl monomer onto a composite worm made of a polyorganosiloxane rubber and an alkyl (meth) acrylate rubber in order to improve the surface appearance of a resin molded product. Copolymers have been proposed, and JP-A-64-79257 has proposed a polycarbonate resin-based resin composition containing this graft copolymer. Further, Japanese Patent Application Laid-Open No. 5-279
Japanese Patent No. 434 discloses a method for improving the pigment coloring property of an impact-resistant resin, in which a vinyl monomer is graft-polymerized to a composite rubber comprising a polyorganosiloxane and an alkyl (meth) acrylate rubber to have a number average particle diameter of 0.1. 01-0.07
It has been proposed to use a graft copolymer in which the particles having a particle size of more than 0.10 μm are not more than 20% by volume.
JP-A-157889 proposes a polycarbonate resin-based resin composition containing the graft copolymer.

Conventionally, all of these graft copolymers containing a composite rubber comprising a polyorganosiloxane and an alkyl (meth) acrylate rubber have been produced by an emulsion polymerization method. Generally, in the emulsion polymerization method, the stability of the polymerized latex against the shearing force is one of the important factors for producing a stable polymer. This is not preferable because the latex collapses due to a shear force or the like given by a pump for performing the polymerization, and the polymer component precipitates and solidifies.

As a method for improving the stability of the polymerized latex against shearing, there are a method of lowering the solid content at the time of polymerization and a method of adding an emulsifier additionally.
From the viewpoint of economy and operability, a method of additionally adding an emulsifier is preferable. However, although the stability of the polymerized latex is improved in accordance with the amount of the emulsifier to be added, when the added amount is increased, the amount of the coagulant required for coagulating and recovering the polymer increases, which is economical. In addition to disadvantages, the coagulant component remaining in the coagulated and recovered polymer increases, and the physical properties and moldability of the resin composition containing the polymer deteriorate.

When coagulating and recovering a polymer from a polymerized latex, it is important to reduce the water content in the polymer after dehydration and before drying. If the water content is high, the polymer is dried. Therefore, a large amount of energy is required, and the treatment time is extended or the size of the apparatus is increased, which is industrially disadvantageous.

[0008]

[Problems to be Solved by the Invention] Japanese Patent Publication No. Hei 8-30102
In the method for producing a graft copolymer disclosed in Japanese Patent Application Laid-Open No. H06-264, there is no description about the stability of a polymerized latex against shear force and the water content after coagulation and recovery. Although the resin composition of JP-79257A is excellent in impact resistance, it has problems in thermal stability such as residence stability in a molding machine at the time of molding and molding appearance at a high temperature molding, and also pigment coloring property. There was a problem.

On the other hand, in the method for producing a graft copolymer disclosed in Japanese Patent Application Laid-Open No. 5-279434, there is no description about the stability of the polymerized latex against the shearing force and the moisture content after coagulation and recovery, and the graft copolymer obtained by this method is not described. Although the resin composition described in JP-A-6-157889 using a polymer is excellent in impact resistance and pigment coloring property, it has poor retention stability in a molding machine during molding and appearance of a molded article during high-temperature molding. There was a problem with thermal stability.

[0010] Also, Japanese Patent Application Laid-Open No. 8-41149 discloses that
A graft copolymer containing a composite rubber composed of polydimethylsiloxane and an alkyl (meth) acrylate rubber having a specific structure and composition is disclosed. However, the stability of a polymerized latex against shear force and the moisture content after coagulation are described. Absent. In addition, this graft copolymer is excellent in impact resistance and pigment coloring property when mixed with an acrylonitrile-styrene copolymer, but when thermoforming a material mixed with a resin having poor thermal stability such as a polycarbonate resin. In addition, there has been a problem that the thermal stability of the entire material is reduced, and the width of the molding temperature condition range is reduced, or the retention stability in the molding machine is insufficient.

That is, conventionally, in a method for producing a graft copolymer containing a composite rubber composed of a polyorganosiloxane and an alkyl (meth) acrylate rubber, the stability of a polymerized latex is excellent, and the water content after coagulation is reduced. Further, no technique has been found for improving the thermal stability and pigment coloring properties of a resin composition mixed with a thermoplastic resin, and there has been a strong demand for the development of a technique that satisfies both of them.

[0012]

Means for Solving the Problems The present inventors have proposed a method for producing a graft copolymer obtained by graft polymerization of a vinyl monomer onto a composite rubber composed of a polyorganosiloxane and an alkyl (meth) acrylate rubber by an emulsion polymerization method. The type of emulsifier used for coagulation and the type of coagulant used when coagulating and collecting the polymerized latex, and the stability of the polymerized latex to the shear force, the water content after coagulation and the resin composition containing the obtained graft copolymer. As a result of intensive studies on physical properties and thermal stability, surprisingly, by coagulating and recovering a polymer latex produced by an emulsion polymerization method using two specific emulsifiers in combination with a specific coagulant, there is an unprecedented superiority Is exhibited, and the resin composition containing the graft copolymer obtained by this method has excellent heat stability, physical properties and Found to exhibit a fee colorability, we have reached the present invention.

That is, the present invention provides: (a) a polyorgano
Siloxane and (b) alkyl (meth) acrylate
(C) aromatic alkenyl compound
Products, methacrylates, acrylates and
At least one kind of vinyl cyanide compound
Graft copolymer latex obtained by graft polymerization of
The graft copolymer (A) obtained by salting out and collecting
After the start of the production of composite rubber,
Before salting out and recovering the sulfonate,
Sulfate emulsifier (1) and carboxylate (2) were added
Manufactured using an aqueous calcium salt solution for salting out.
Graft copolymer (A) and thermoplastic resin (B)
And a thermoplastic resin composition comprising:

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Graft copolymer (A) of the present invention
The polyorganosiloxane (a) used in the production method of
Although not particularly limited, a polyorganosiloxane containing a vinyl polymerizable functional group is preferable. 0.3 to 3 siloxane units containing vinyl polymerizable functional groups
More preferably, it is composed of 97 to 99.7 mol% of dimethylsiloxane units and the silicon atom having three or more siloxane bonds is 1 mol% or less based on all silicon atoms in the polydimethylsiloxane.

If the amount of the siloxane unit having a vinyl polymerizable functional group in the polyorganosiloxane (a) is less than 0.3% by mole, the complexation with the alkyl (meth) acrylate rubber (b) tends to be insufficient, and the graft copolymerization is difficult. Inferior appearance due to bleed-out of the polyorganosiloxane on the surface of the resin composition molded article containing the union is likely to occur. In addition, when the vinyl polymerizable functional group-containing siloxy unit in the polyorganosiloxane exceeds 3 mol%, or when the silicon atom having three or more siloxane bonds exceeds 1 mol% based on all silicon atoms in the polyorganosiloxane. , The impact resistance of the resin composition containing the graft copolymer tends to be low.

Further, considering both the impact resistance and the molded appearance of the resin composition containing the graft copolymer, the amount of the siloxane unit having a vinyl polymerizable functional group in the polyorganosiloxane (a) is 0.5 to 2 mol%. Is preferably
More preferably, it is 0.5 to 1 mol%.

The amount of the polyorganosiloxane (a) in the composite rubber in the production method of the present invention is preferably 1 to 20% by weight. If it is less than 1% by weight, the impact resistance tends to be low due to the small amount of polyorganosiloxane,
If the amount is more than 10% by weight, the pigment coloring property of the resin composition molded article containing the graft copolymer (A) tends to decrease. Also,
In consideration of both impact resistance and pigment coloring of the resin composition containing the graft copolymer (A), the amount of the polyorganosiloxane in the composite rubber is preferably 6 to 20% by weight, more preferably 10 to 20% by weight. % By weight.

The method for producing the polyorganosiloxane (a) includes a latex obtained by emulsifying a mixture of a dimethylsiloxane compound and a siloxane containing a vinyl polymerizable functional group or, if necessary, a mixture containing a siloxane-based crosslinking agent with an emulsifier and water. Is atomized using a homomixer that atomizes by shearing force due to high-speed rotation or a homogenizer that atomizes by jet power from a high-pressure generator, and then polymerized at high temperature using an acid catalyst, and then an alkaline substance. To neutralize the acid. As a method for adding the acid catalyst used for the polymerization, a siloxane mixture,
There are a method of infiltrating with an emulsifier and water, a method of dropping a latex in which a siloxane mixture is finely divided into a high-temperature acid aqueous solution at a constant speed, etc., in consideration of the ease of controlling the particle diameter of polyorganosiloxane A method in which the latex in which the siloxane mixture is finely divided is dropped at a constant rate into a high-temperature aqueous acid solution is preferable.

Although the size of the polyorganosiloxane particles is not particularly limited, the weight average particle diameter is preferably 0.2 μm or less, and more preferably, in consideration of the pigment coloring property of the resin composition containing the graft copolymer (A). Is 0.1 μm
It is as follows.

The dimethylsiloxane compound used in the production of the polyorganosiloxane (a) includes a cyclic dimethylsiloxane having three or more member rings, preferably a three- to six-membered ring. Specific examples include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and the like. These may be used alone or as a mixture of two or more.

The siloxane containing a vinyl polymerizable functional group is a siloxane containing a vinyl polymerizable functional group and capable of bonding to a dimethyl siloxane compound through a siloxane bond. Considering the reactivity with the dimethyl siloxane compound, Various alkoxysilane compounds containing a vinyl polymerizable functional group are preferred. Specifically, β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane, γ-methacryloyloxypropylmethoxydimethylsilane,
methacryloyloxysiloxanes such as γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane and δ-methacryloyloxybutyldiethoxymethylsilane, tetramethyltetravinylcyclotetrasiloxane And mercaptosiloxanes such as p-vinylphenyldimethoxymethylsilane and γ-mercaptopropyldimethoxymethylsilane and γ-mercaptopropyltrimethoxysilane. These vinyl polymerizable functional group-containing siloxanes can be used alone or as a mixture of two or more.

As the siloxane crosslinking agent, a trifunctional or tetrafunctional silane crosslinking agent such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane and the like are used. .

As the emulsifier used in the production of the polyorganosiloxane (a), an anionic emulsifier is preferable, and an emulsifier selected from sodium alkylbenzene sulfonate, sodium polyoxyethylene nonylphenyl ether sulfate and the like. Is used. Particularly, sulfonic acid emulsifiers such as sodium alkylbenzene sulfonate and sodium lauryl sulfonate are preferable. These emulsifiers are used in an amount of about 0.05 to 5 parts by weight based on 100 parts by weight of the siloxane mixture. If the amount used is small, the dispersion state becomes unstable and the emulsified state with a fine particle diameter cannot be maintained. On the other hand, if the amount is too large, the resin composition molded article caused by the emulsifier becomes extremely colored, which is inconvenient.

The method of mixing the siloxane mixture, emulsifier, water and / or acid catalyst includes mixing by high-speed stirring and mixing by a high-pressure emulsifying device such as a homogenizer. The method using a homogenizer is a method of mixing a polyorganosiloxane latex. This is a preferable method because the particle size distribution is reduced.

Examples of the acid catalyst used for the polymerization of the polyorganosiloxane (a) include sulfonic acids such as aliphatic sulfonic acids, aliphatic substituted benzenesulfonic acids and aliphatic substituted naphthalenesulfonic acids, and mineral acids such as sulfuric acid, hydrochloric acid and nitric acid. Is mentioned. These acid catalysts are used alone or in combination of two or more. Further, among these, aliphatic substituted benzenesulfonic acid is preferable in that it is also excellent in stabilizing action of the polyorganosiloxane latex,
n-Dodecylbenzenesulfonic acid is particularly preferred. When n-dodecylbenzenesulfonic acid and a mineral acid such as sulfuric acid are used in combination, the coloring of the resin composition due to the emulsifier component of the polyorganosiloxane latex can be reduced.

The polymerization temperature of the polyorganosiloxane (a) is preferably 50 ° C. or higher, more preferably 80 ° C. or higher. The polymerization time of the polyorganosiloxane (a) is 2 hours or more, more preferably 5 hours or more, when the acid catalyst is mixed with a siloxane mixture, an emulsifier, and water to form fine particles and polymerized. In the method of lowering the latex in which the siloxane mixture has become fine particles, it is preferable to hold the latex for about 1 hour after completion of dropping of the latex.

The termination of the polymerization can be carried out by cooling the reaction solution and neutralizing the latex with an alkaline substance such as caustic soda, caustic potash and sodium carbonate.

The alkyl (meth) acrylate rubber (b) constituting the graft copolymer (A) is a polymer of an alkyl (meth) acrylate and a polyfunctional alkyl (meth) acrylate, and the composite rubber is a polyorgano rubber. It can be produced by impregnating the siloxane (a) latex with an alkyl (meth) acrylate component composed of an alkyl (meth) acrylate and a polyfunctional alkyl (meth) acrylate, followed by polymerization. Examples of the alkyl (meth) acrylate include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and hexyl methacrylate, 2-ethylhexyl methacrylate, and n-
Examples thereof include alkyl methacrylates such as lauryl methacrylate, and use of n-butyl acrylate is particularly preferable.

Examples of the polyfunctional alkyl (meth) acrylate include allyl methacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, triallyl cyanurate. , Triallyl isocyanurate and the like. The amount of the polyfunctional alkyl (meth) acrylate used is 0.1 to 20% by weight, preferably 0.2 to 5% by weight in the alkyl (meth) acrylate component.
More preferably, it is 0.2 to 1% by weight. The alkyl (meth) acrylate and the polyfunctional alkyl (meth) acrylate are used alone or in combination of two or more.

The composite rubber comprising the polyorganosiloxane (a) and the alkyl (meth) acrylate rubber (b) used in the present invention is prepared by adding the above-mentioned alkyl (meth) acrylate component to the latex of the polyorganosiloxane component, It can be prepared by allowing a radical polymerization initiator to act to polymerize. As a method of adding the alkyl (meth) acrylate, there are a method of mixing the poly (organosiloxane component) with the latex of the polyorganosiloxane component at a time and a method of dropping into the latex of the polyorganosiloxane component at a constant rate. In consideration of the impact resistance of the obtained resin composition containing the graft copolymer, a method of mixing the latex of the polyorganosiloxane component at a time is preferable. Also,
As the radical polymerization initiator used for the polymerization, peroxide,
An azo initiator or a redox initiator obtained by combining an oxidizing agent and a reducing agent is used. Among these, a redox initiator is preferable, and a sulfoxylate initiator obtained by combining sodium salt, Rongalit, and hydroperoxide with ferrous sulfate / ethylenediaminetetraacetic acid is particularly preferable.

In the graft copolymer (A) according to the method of the present invention, at least one monomer selected from aromatic alkenyl compounds, methacrylates, acrylates and vinyl cyanide compounds is graft-polymerized. The amount of the graft component (c) is not particularly limited, but is preferably 50 to 80% by weight, more preferably 50 to 70% by weight, and more preferably 50 to 70% by weight.
60% by weight. If the amount is less than 50% by weight, the pigment coloring property of the resin composition molded article containing the graft copolymer tends to decrease. If the amount exceeds 80% by weight, the rubber amount becomes low, so that the impact resistance tends to be low.

The aromatic alkenyl compounds include, for example, styrene, α-methylstyrene, vinyltoluene and the like. The methacrylic esters include, for example, methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate and the like. Examples thereof include methyl acrylate, ethyl acrylate, and butyl acrylate. Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile. Among them, a mixture of styrene and acrylonitrile is preferable in consideration of compatibility with the thermoplastic resin (B) described later.

In the graft polymerization, the composite rubber ((a) +
At least one monomer selected from aromatic alkenyl compounds, methacrylic esters, acrylic esters and vinyl cyanide compounds is added to the latex of (b), and the reaction can be carried out in one step or in multiple steps by a radical polymerization method. However, in consideration of the impact resistance and pigment coloring of the obtained resin composition containing the graft copolymer (A), the polymerization is preferably performed in two or more stages. As the radical polymerization initiator used for the polymerization, a peroxide, an azo initiator, or a redox initiator obtained by combining an oxidizing agent and a reducing agent is used. Among these, a redox initiator is preferable, and a sulfoxylate initiator obtained by combining sodium salt, Rongalit, and hydroperoxide with ferrous sulfate / ethylenediaminetetraacetic acid is particularly preferable.

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

The particle size of the graft copolymer (A) prepared as described above is not particularly limited, but the impact resistance and pigment coloring of the resin composition containing the obtained graft copolymer are not limited. Considering both properties, the number average particle diameter is preferably 0.10 to 0.5 μm, more preferably 0.10 to 0.30 μm, and more preferably 0.10 to 0.30 μm.
0 to 0.15 μm.

The method for producing the graft copolymer of the present invention comprises:
An emulsifier must be additionally added at a stage after the production of the composite rubber is started and before the salting out and recovery of the graft copolymer latex is performed.

When the polymerization is carried out only with the emulsifier contained in the polyorganosiloxane (a) latex without adding an emulsifier, the stability of the polymerized latex against shearing force is low, The latex is easily disintegrated due to the shearing force of the pump for transferring the latex after polymerization, and the polymerization cullet or the pump is blocked, which is not preferable.

In general, the stability of the polymerized latex against the shearing force is determined by the time required for applying a shearing force to the latex using a stirring and mixing device such as a homomixer, until the latex collapses and the flow due to stirring stops. Considering the shear force caused by the transfer pump or the stirring during polymerization which is generally used in industry, the preferred range of the time until the flow is stopped (hereinafter referred to as flow stop time) measured by the above method using a homomixer is 3 Minutes or more, more preferably 5 minutes or more. When the flow stop time measured by this method is 1 minute or less, the stability of the polymerized latex against the shearing force is insufficient. The latex disintegrates soon, causing blockage of the polymerization cullet or pump.

In the method for producing a graft copolymer according to the present invention, the emulsifiers to be added additionally include a sulfonate or sulfate emulsifier (1) and a carboxylate emulsifier (2).
To be used together. Sulfonate or sulfate emulsifier (1)
When only the addition is performed, the stability of the polymerized latex against the shearing force is insufficient, and the moisture content after coagulation increases. In order to improve this, it is necessary to increase the amount of the emulsifier, but if the amount of the emulsifier is increased, the coagulation recovery of the latex and the thermal stability of the resin composition containing the graft copolymer are impaired. On the other hand, when only the carboxylate emulsifier (2) is additionally added, the thermal stability of the resin composition containing the graft copolymer is impaired.

As the salt emulsifier (1), sulfonic acid emulsifiers such as sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate, sodium alkyldiphenyletherdisulfonate, and naphthalenesulfonic acid formalin condensate, and lauryl sulfate Sulfate emulsifiers such as sodium, sodium stearyl sulfate, polyoxyethylene alkyl ether sulfate and polyoxyethylene alkyl phenyl ether sulfate are exemplified, and one or more of these can be used. Among these, polyoxyethylene alkyl phenyl ether sulfate is preferred in consideration of the thermal stability of the resin composition containing the graft copolymer.

On the other hand, examples of the carboxylate emulsifier (2) include various refined fatty acid soaps such as tallow fatty acid soap, coconut oil fatty acid soap, rosin acid soap, stearates and oleates, dipotassium alkenylsuccinate and N
And N-acyl sarcosine salts such as sodium lauroyl sarcosine. Among them, dipotassium alkenyl succinate is preferable in consideration of the stability of the polymerized latex against the shearing force and the moisture content after coagulation.

The emulsifiers (1) and (2) are used in necessary amounts in consideration of the stability of the polymerized latex against the shearing force. The preferred range of the amount of the emulsifier (1) used is 0.01 to 5 parts by weight, more preferably 0.1 to 1.0 part by weight, based on the solid content in the polymerized latex. Also emulsifier (2)
The preferred range of the amount used is 0.01 to 5 parts by weight, more preferably 0.1 to 5 parts by weight, based on the solid content in the polymerization latex.
1.0 part by weight.

The method of adding the emulsifiers (1) and (2) is as follows.
Addition before impregnating and polymerizing acrylate, addition before graft-polymerizing at least one monomer selected from aromatic alkenyl compounds, methacrylates, acrylates or vinyl cyanide compounds, graft polymerization The addition can be carried out at any time during the addition until the completion and before the salting out after the completion of the graft polymerization. The order of adding the emulsifiers (1) and (2) is not particularly limited.

In the method for producing a graft copolymer of the present invention, after performing the graft polymerization, this polymerized latex is poured into an aqueous calcium solution and salted out to recover the graft copolymer. As the calcium salt used,
Examples include water-soluble calcium salts such as calcium chloride, calcium acetate, calcium nitrate and calcium bromide. Among them, calcium chloride and calcium acetate are preferable in view of coagulation and economy. The amount of the calcium salt used is not particularly limited, but if too small, coagulation and recovery cannot be performed, and if too large, the amount of calcium element remaining in the coagulated and collected graft copolymer increases, The thermal stability of the resin composition containing the graft copolymer tends to decrease.

The amount of calcium element remaining in the graft copolymer can also be reduced by washing the coagulated and recovered polymer with water. Considering the thermal stability of the resin composition containing the graft copolymer, the preferred amount of the remaining calcium element is 5000 ppm or less, more preferably 1000 ppm or less, and particularly preferably 50 ppm or less.
It is 0 ppm or less.

When a salt other than a calcium salt such as a magnesium salt or an aluminum salt is used as a coagulant, the obtained graft copolymer is mixed with another thermoplastic resin to be used as a resin composition. In addition, the impact resistance of the molded product is low, and the molded product is inferior in thermal stability.

In the method for producing a graft copolymer of the present invention, the graft copolymer coagulated as described above is separated and recovered from water, and then the moisture in the polymer is removed by a drying treatment. From the viewpoint of the amount of energy required for the drying treatment, the smaller the amount of water in the graft copolymer after the coagulation and recovery and before the drying, the better. When using a fluid drying apparatus or flash drying apparatus that is usually used industrially, in consideration of the drying capacity of the apparatus and the processing time, a preferable range of the moisture content in the graft copolymer before the drying operation after the coagulation recovery is: It is at most 50% by weight, more preferably at most 40% by weight, based on the polymer that has absorbed moisture.

The graft copolymer (A) produced by the production method of the present invention can be used in various applications as a resin composition mixed with a thermoplastic resin (B).

The thermoplastic resin (B) to be mixed with the graft copolymer (A) is not particularly limited, but a thermoplastic resin which remarkably exhibits the characteristics of the graft copolymer produced by the production method of the present invention. Examples of the resin include a polycarbonate resin or a mixture of a polycarbonate resin and another thermoplastic resin.

As the polycarbonate resin, a resin produced by a known method is used. That is, a transesterification reaction between a diester of carbonic acid obtained from a monofunctional aromatic or aliphatic hydroxy compound and a dihydroxy compound, and a transesterification reaction between a dihydroxy compound and itself or another dihydroxy compound with a bisalkyl or bisallyl carbonate. A reaction method between a dihydroxy compound and phosgene in the presence of an oxygen binder, and a reaction method between a dihydroxy compound and a bischlorocarbonate of the dihydroxy compound in the presence of an oxygen binder. Typically, there is a production method in which bisphenol A is reacted with carbonyl chloride in the presence of an oxygen binder and a solvent.

Other thermoplastic resins used in the mixture with the polycarbonate resin include acrylonitrile-styrene copolymer, N-phenylmaleimide-acrylonitrile-styrene copolymer, polystyrene, high-impact polystyrene, ABS resin, and AAS resin. , AES resin, ACS resin, polymethyl methacrylate, methyl methacrylate-styrene copolymer, polybutylene terephthalate, polyethylene terestarate, polyester elastomer, urethane elastomer, polyether elastomer, styrene elastomer, acrylic elastomer, Examples thereof include polypropylene, polyethylene, and olefin-based elastomers, which can be used alone or as a mixture of two or more.

The mixing ratio of the graft copolymer (A) to the thermoplastic resin (B) is not particularly limited,
In order to make the properties of the thermoplastic resin effective, the graft copolymer (A) is 0.01 to 80% by weight, the thermoplastic resin (B) is 20 to 99.9% by weight, and more preferably the graft copolymer. 1 to 50% by weight of the copolymer (A), 50 to 99% by weight of the thermoplastic resin (B), particularly preferably 1 to 30% by weight of the graft copolymer (A) and 70 to 70% by weight of the thermoplastic resin (B). 99% by weight.

The resin composition comprising the graft copolymer (A) and the thermoplastic resin (B) according to the present invention can be produced by extrusion molding using a usual known kneading machine. Examples of such a molding machine include an extruder, an injection molding machine, a blow molding machine, a calender molding machine, and an inflation molding machine.

The resin composition containing the graft copolymer (A) may further contain a dye, a pigment, a stabilizer, a reinforcing agent, a filler, a flame retardant and the like, if necessary.

The use of the thermoplastic resin containing the graft copolymer according to the present invention is not particularly limited. For example, when the thermoplastic resin contains a polycarbonate resin, it may be used for automobile exterior parts, automobile interior parts, and various OA equipment. Examples include housings, chassis parts for OA equipment, housings for home appliances, tableware applications, display parts, and various building materials.

[0056]

The present invention will be described below with reference to examples. In Reference Examples, Examples and Comparative Examples, "parts" and "%" are "parts by weight" and "% by weight" unless otherwise specified.
Means 1) The weight average particle diameter of the polyorganosiloxane in the latex and the weight average particle diameter of the graft copolymer in the latex were determined by a dynamic light scattering method using DLS-700 manufactured by Otsuka Electronics Co., Ltd. . 2) The stability of the polymerized latex with respect to the shearing force was determined by keeping 300 g of the polymerized latex in a beaker at 50 ° C. and homogenizing it with a homomixer (T.R.
K. The stirring was carried out under the conditions of 10,000 revolutions per second with an AUTO homomixer, and the time required for the latex to collapse due to the shearing force due to the stirring and to stop the flow by solid analysis was measured. 3) The moisture content in the polymer after coagulation and before drying was measured by measuring the weight before drying and the weight after drying when the centrifugally dehydrated graft copolymer was dried at 85 ° C., and calculated by the following formula. . Moisture percentage (%) = (weight before drying−weight after drying) / weight before drying × 100 4) The calcium element concentration in the graft copolymer was determined by ashing a predetermined amount of the graft polymer at 600 ° C. The determination was performed by quantifying calcium by atomic absorption spectrometry from an aqueous hydrochloric acid solution. 5) Izod impact strength was measured by a method based on ASTM D258. 6) Surface hardness (Rockwell hardness) is measured by ASTM
The test was performed according to a method based on D785. 7) Pigment coloring property is injection molding machine IS-1 manufactured by Toshiba Machine Co., Ltd.
1 molded at 250 ° C. cylinder temperature using 00EN
JIS using 00mm × 100mm × 3mm black colored plate
It was evaluated by hue measurement according to Z8729. 8) The evaluation of the molded appearance was carried out by visually observing the presence or absence of molding fogging and silver on the surface of the molded plate and measuring the glossiness. 9) The retention stability at the time of injection molding was determined by using an injection molding machine set at a cylinder temperature of 260 ° C. and measuring 100 mm × 10
After molding a molded article having a shape of 0 mm × 3 mm for 20 shots under the condition of one cycle 60 seconds, the molding is interrupted for 15 minutes while the resin remains in the cylinder, and the second shot is formed after the molding is started. This was performed by visual observation of the molded appearance of the product and measurement of glossiness.

Reference Example 1 Polyorganosiloxane (L-
1) Production of Latex 98 parts of octamethylcyclotetrasiloxane and 2 parts of γ-methacryloyloxypropyldimethoxymethylsilane were mixed to obtain 100 parts of a siloxane-based mixture. To this, 300 parts of distilled water in which 0.67 part of sodium dodecylbenzenesulfonate is dissolved is added, and 10 parts are added with a homomixer.
After stirring at 2,000 rpm for 2 minutes, the mixture was passed through a homogenizer once at a pressure of 300 kg / cm ² to obtain a stable premixed organosiloxane latex.

On the other hand, 10 parts of dodecylbenzenesulfonic acid and 90 parts of distilled water were injected into a reactor equipped with a reagent injection container, a cooling pipe, a jacket heater and a stirrer.
A 0% dodecylbenzenesulfonic acid aqueous solution was prepared.
While the aqueous solution was heated to 85 ° C., the premixed organosiloxane latex was added dropwise over 4 hours, and after the completion of the addition, the temperature was maintained for 1 hour and cooled. The reaction was then neutralized with aqueous sodium hydroxide.

The latex thus obtained was mixed with 17
When the solid content was determined by drying at 0 ° C. for 30 minutes, 17.
7%. The weight average particle diameter of the polyorganosiloxane in the latex was 0.05 μm.

Reference Example 2 Polyorganosiloxane (L-
2) Production of latex 97.5 parts of octamethyltetracyclosiloxane, γ-
Methacryloxypropyldimethoxymethylsilane 0.
5 parts and ethyl orthosilicate 2 parts were mixed to obtain 100 parts of a siloxane-based mixture. To this was added 0.67 parts of sodium dodecylbenzenesulfonate and 200 parts of distilled water in which 1 part of dodecylbenzenesulfonate was dissolved, and the mixture was stirred with a homomixer at 10,000 rpm for 2 minutes, and then added to a homogenizer at 300 kg / cm ^2. Once to obtain a stable premixed organosiloxane latex. This mixed solution was transferred into a reactor equipped with a cooling pipe, a jacket heater and a stirrer, heated at 85 ° C. for 5 hours while stirring and mixing, and allowed to stand at 30 ° C .; Was neutralized to pH 7.

The latex thus obtained was mixed with 17
After drying at 0 ° C. for 30 minutes to determine the solid content, 29.
It was 0%. The average particle size of the polyorganosiloxane in the latex was 0.21 μm.

Example 1 Production of Graft Copolymer (S-1) and Production of Resin Composition The production was carried out in Reference Example 1 in a reactor equipped with a reagent injection vessel, a cooling pipe, a jacket heater and a stirring device. 56.5 parts of a polyorganosiloxane latex (L-1) and 0.2 parts of Emal NC-35 (polyoxyethylene alkylphenyl ether sulfate; manufactured by Kao Corporation) were collected, and 148.5 parts of distilled water was collected. After addition and mixing, 40 parts of butyl acrylate, 0.3 part of allyl methacrylate,
A mixture of 0.1 part of 3-butylene glycol dimethacrylate and 0.18 part of cumene hydroperoxide was added.

The atmosphere was replaced with nitrogen by passing a nitrogen stream through the reactor, and the temperature was raised to 60 ° C. When the internal liquid temperature reaches 60 ° C., ferrous sulfate 0.00
01 parts, ethylenediaminetetraacetic acid disodium salt 0.0
An aqueous solution in which 003 parts and 0.24 parts of Rongalite were dissolved in 10 parts of distilled water was added to initiate 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 has dropped to 70 ° C.,
An aqueous solution obtained by dissolving 0.4 part of Rongalite in 10 parts of distilled water is added, and then 7.5 parts of acrylonitrile, 22.5 parts of styrene and 0.1 parts of cumene hydroperoxide are added.
4 parts of the mixture was added dropwise over 2 hours to carry out polymerization. After completion of the dropping, the temperature of 60 ° C. was maintained for 1 hour, and then 0.0002 part of ferrous sulfate, 0.0006 part of ethylenediaminetetraacetic acid disodium salt, 0.23 part of Rongalite and 0.2 part of Emal NC-35 Was dissolved in 10 parts of distilled water, and then acrylonitrile 5.0 was added.
, 15.0 parts of styrene and 0.10 parts of cumene hydroperoxide were dropped and polymerized over 2 hours. After completion of the dropping, the temperature of 60 ° C. was maintained for 1 hour and then cooled. Then, 0.3 part of latemul ASK (dipotassium alkenyl succinate; manufactured by Kao Corporation) was added, and polyorganosiloxane, butyl acrylate rubber and Was obtained by graft-polymerizing acrylonitrile and styrene onto the composite rubber made of the above, to obtain a polymerized latex of a graft copolymer (S-1). The average particle size of the graft copolymer in the latex determined by the dynamic light scattering method was 0.12 μm.
Further, the stability of this polymerized latex against shearing force was as good as 5 minutes in a homomixer test.

Next, 150 parts of an aqueous solution in which calcium acetate was dissolved at a ratio of 1% was heated to 60 ° C. and stirred. In this, 100 parts of a latex of a graft copolymer was gradually dropped and solidified. Next, the precipitate was separated, washed, and then centrifuged using a centrifuge (H-130E, manufactured by Domestic Centrifuge Co., Ltd.).
Dehydration treatment was performed for 2 minutes at the condition of 00 rotations per second. The water content of the obtained powdery graft copolymer was 35% by weight.

Next, the resultant was dried at 85 ° C. for 24 hours to obtain a graft copolymer (S-1). The calcium concentration in this graft copolymer (S-1) was 300 ppm.

Then, 20 parts of the graft copolymer, 50 parts of a polycarbonate resin (Iupilon S2000F, manufactured by Mitsubishi Engineering-Plastics Corporation) and SAN
Resin (Slilac AS709, manufactured by Asahi Kasei Corporation) 3
0 parts were added, and 0.8 part of carbon black (CB-960, manufactured by Mitsubishi Chemical Corporation) was further added as a colorant, followed by thorough mixing using a Hensiel mixer. These mixtures were shaped by a twin-screw extruder set at a barrel temperature of 260 ° C. to produce pellets. Test pieces were molded from the obtained pellets using an injection molding machine set at a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. The Izod impact strength and Rockwell hardness were evaluated using the test pieces.

Further, 100 × 10 4
A flat plate having a shape of 0 × 3 mm was injection-molded, and the pigment coloring property, the appearance of the molded article, and the retention stability during injection molding were evaluated. The results are shown in Table 1.

Example 2 Production of Graft Copolymer (S-2) and Production of Tree Composition In the procedure for producing the graft copolymer (S-1) of Example 1, the polyorganosiloxane latex used was L-
And the amount of distilled water charged to the reactor was changed to 170.5 parts, and the polymerization of the graft copolymer (S-2) was changed in the same manner. Latex was obtained. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.29 μm. Further, the stability of this polymerized latex against shearing force was as good as 5 minutes in a homomixer test.

Next, coagulation and dehydration were performed in the same manner as in Example 1. The water content of the obtained powdery graft copolymer was 33%. After drying at 85 ° C. for 24 hours, a graft copolymer (S-2) was obtained. The calcium concentration in this graft copolymer (S-2) was 300 pp
m.

A resin composition pellet comprising the graft copolymer (S-2), the polycarbonate resin and the SAN resin was produced in the same manner as in Example 1, and the pellet was evaluated in the same manner as in Example 1. . The results are shown in Table 1.

Comparative Example 1 Production of Graft Copolymer (T-1) and Production of Resin Composition Emul NC-35 was not added at the time of production of the composite rubber and at the start of the graft polymerization, and latemul ASK was used during the graft polymerization. A polymerization latex of the graft copolymer (T-1) was obtained in exactly the same manner as in Example 1 except that was not added. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.15 μm.
m. The stability of this polymerized latex to shearing force was extremely low at 1 minute in a homomixer test.

Next, coagulation and dehydration were performed in the same manner as in Example 1. The water content of the obtained powdery graft copolymer was 38%. Dried at 85 ° C for 24 hours,
A graft copolymer (T-1) was obtained. The calcium concentration in this graft copolymer (T-1) was 250 ppm.

A resin composition pellet comprising the graft copolymer (T-1), the polycarbonate resin and the SAN resin was produced in the same manner as in Example 1, and the pellet was evaluated in the same manner as in Example 1. . The results are shown in Table 1.

Comparative Example 2 Production of Graft Copolymer (T-2) and Production of Resin Composition Latemul ASK added during graft polymerization was converted to Emal N
A polymerization latex of a graft copolymer (T-2) was obtained in exactly the same manner as in Example 1 except that C-35 was used. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.12 μm. Also, the stability of this polymerized latex against shear force is
The homomixer test was as good as 5 minutes.

The water content of the obtained powdery graft copolymer showed a very high value of 50%. After drying at 85 ° C. for 24 hours, a graft copolymer (T-2) was obtained. The calcium concentration in the graft copolymer (T-2) is 25
It was 0 ppm.

In the same manner as in Example 1, resin composition pellets comprising the graft copolymer (T-2), the polycarbonate resin and the SAN resin were produced, and the pellets were evaluated in the same manner as in Example 1. . The results are shown in Table 1.

Comparative Example 3 Production of Graft Copolymer (T-3) and Production of Resin Composition In place of Emal NC-35 added at the time of production of the composite rubber and at the start of graft polymerization, it was changed to Latemul ASK and added. Except for this, a polymerization latex of the graft copolymer (T-3) was obtained in exactly the same manner as in Example 1. The weight average particle diameter of the graft copolymer in the latex determined by the dynamic light scattering method was 0.12 μm. Further, the stability of this polymerized latex against shearing force was as good as 5 minutes in a homomixer test.

The water content of the obtained powdery graft copolymer was 30%. After drying at 85 ° C. for 24 hours, a graft copolymer (T-3) was obtained. The calcium concentration in this graft copolymer (T-3) was 1500 ppm.

A resin composition pellet comprising the graft copolymer (T-3), a polycarbonate resin and a SAN resin was produced in the same manner as in Example 1, and the pellet was evaluated in the same manner as in Example 1. . The results are shown in Table 1.

Comparative Example 4 Production of Graft Copolymer (T-4) and Production of Resin Composition Except that the coagulant used in the production procedure of the graft copolymer of Example 1 was changed from calcium acetate to aluminum sulfate. A graft polymer (T-4) was obtained in the same manner. The water content of the obtained powdery graft copolymer is 30.
% By weight.

In the same manner as in Example 1, the graft copolymer (T-4), polycarbonate resin and SA
A resin composition pellet made of N resin was produced, and the same evaluation as in Example 1 was performed on the pellet. The results are shown in Table 1.

[0083]

[Table 1]

From the above Examples and Comparative Examples, the following became clear. 1) When a graft copolymer is produced by the methods of Examples 1 and 2, the stability of the polymerized latex is high, and the moisture content after coagulation and before drying is low at 35% and 33%. When the graft copolymer is produced on an industrial scale, the latex can be stably produced without disintegration due to shearing force of a stirring or transfer pump, and the water content is 40% or less.
Less energy is spent in drying the water. 2) The resin compositions of Examples 1 and 2 exhibited high Izod impact strength, good molded appearance, and good retention stability during injection molding. 3) The resin composition of Example 1 had excellent pigment coloring properties. 4) When the graft copolymer is produced by the method of Comparative Example 1, the stability of the polymerized latex by the homomixer method is as low as 1 minute, and thus the polymerized latex having poor stability against shearing force is produced on an industrial scale. In the case of production, latex may be easily disintegrated due to stirring during polymerization or shearing force of a transfer pump or the like, and a polymer component may be precipitated and solidified. 5) When the graft copolymer is produced by the method of Comparative Example 2, although the stability of the polymerized latex is good, the moisture content after coagulation and before drying is as high as 50%, and the energy required for the drying treatment is large. This leads to an increase in the processing time or an increase in the size of the drying equipment. 6) When the graft copolymer is produced by the methods of Comparative Examples 3 and 4, the stability of the polymerized latex and the moisture content after coagulation and before drying are good, but the resin containing the graft copolymer produced by this method is good. The Izod impact strength of the composition was low, and the molding appearance of the injection molded plate and the retention stability during injection molding were both poor.

[0085]

Industrial Applicability The method for producing a graft copolymer of the present invention is excellent in stability against shearing force of a polymerized latex and reduction of moisture content after coagulation and before drying. Can be manufactured on a scale. Further, the thermoplastic resin composition containing the graft copolymer produced by the method of the present invention has impact resistance, surface hardness, molded appearance,
It has an excellent balance of pigment coloring properties and also has excellent heat stability during injection molding, and is useful as various industrial materials.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuaki Ii 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Otake Works Resin Development Center (56) References JP-A-4-306212 (JP) , A) JP-A-9-20815 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 291/02

Claims (2)

(57) [Claims] 1. A composite rubber comprising (a) a polyorganosiloxane and (b) an alkyl (meth) acrylate rubber, and (c) an aromatic alkenyl compound, a methacrylate, an acrylate and a vinyl cyanide compound. A graft copolymer (A) obtained by salting out and recovering a graft copolymer latex obtained by graft polymerization of at least one monomer, wherein the graft copolymer latex is salted out after production of the composite rubber is started. Before collection, sulfonate or sulfate emulsifier (1)
And carboxylate (2) are added , and the graft copolymerization is carried out using an aqueous calcium salt solution for salting out.
Thermoplastic tree comprising body (A) and thermoplastic resin (B)
Fat composition. 2. The method according to claim 1, wherein the thermoplastic resin (B) is a polycarbonate resin.
Resin or polycarbonate resin and other thermoplastic resin
The thermoplastic resin composition according to claim 1, which is a mixture of the following.