JP2906112B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin composition having excellent chemical resistance and impact resistance.

[0002]

2. Description of the Related Art Rubber-reinforced styrene resins represented by ABS resins have been used in a wide range of fields as parts of household products and vehicles because of their excellent impact strength. Therefore, in some cases, it may be used under the condition exposed to chemicals. For example, resin products such as a washing handle and a shower head in a wash basin and a bathroom are in an environment exposed to a detergent, and a resin component used in an automobile comes into contact with mechanical oil or a wax remover. Further, the resin used for the handle and the door cap of the refrigerator is exposed to CFC, which is a urethane foaming agent, at the time of manufacturing the insulating material of the refrigerator. Under such circumstances, the resin product often cracks or fine cracks are generated on the resin surface. This phenomenon, called cracking under environmental stress, occurs when the residual strain inside the molded rubber-reinforced styrenic resin product is partially released by contact with chemicals, causing the resin to dissolve. Notably visible on low chemical contact.
As a means for improving the chemical resistance (prone of cracking under environmental stress) of the rubber-reinforced styrene resin, there is a method of using a crosslinked alkyl acrylate rubber as a rubber component. An example is an AAS resin obtained by graft copolymerizing acrylonitrile and styrene on a crosslinked butyl acrylate rubber. However, AAS resins have a drawback of low impact strength, and their use as resin products is greatly restricted. In order to obtain high impact strength, it is usually possible to take measures to increase the rubber content. However, it is not preferable because the surface hardness and rigidity are reduced, causing scratches and deformation. Therefore, a rubber-reinforced styrene-based resin that is excellent in both chemical resistance and impact strength is desired.

[0003]

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies to obtain a resin composition having an excellent balance of physical properties between chemical resistance and impact strength, and as a result, have found that an alkyl acrylate and a conjugated diene rubber have been used. Graft copolymer using a rubber obtained by seed polymerization of an alkyl acrylate on a conjugated diene rubber and graft copolymer using a rubber obtained by seed polymerization of an alkyl acrylate on a polyorganosiloxane rubber One or more graft copolymers selected from and a graft copolymer using a conjugated diene rubber as an essential component,
With a hard thermoplastic resin as necessary, by blending so that the ratio of the rubber component in the thermoplastic composition becomes a specific composition, excellent in physical properties balance between chemical resistance and impact strength development Finding that a resin composition can be obtained,
The present invention has been reached.

[0004]

Means for Solving the Problems The gist of the present invention is that the following graft copolymer (I) and graft copolymer (II) are essential components, and the graft copolymer (I) and the graft copolymer (II) ) And a hard thermoplastic resin (III), wherein the proportion of the rubbery copolymer in 15% by weight of the thermoplastic resin composition is 15%.
-30% by weight, and the ratio of the alkyl acrylate unit forming the rubbery polymer is 10% by weight.
A thermoplastic resin composition characterized by being 35 to 85% by weight relative to 0% by weight. (I) The following graft copolymers (A), (B) and (C)
At least one graft copolymer (I) selected from the group consisting of: (A) 35-85% by weight of alkyl acid alkyl ester
The gel content obtained by emulsion polymerization of 15 to 65% by weight of a conjugated diene and 0 to 20% by weight of a copolymerizable monomer with the conjugated diene exceeds 70% by weight, and the average particle size is 0.03 to 0.2%.
μm rubbery copolymer (a) latex, acid group-containing copolymer latex (i) or, if necessary, metal salt of oxygen acid (ii) with acid group-containing copolymer latex (i) The average particle diameter obtained by performing
5 μm enlarged rubbery copolymer (a ′) latex 20
15 to 45% by weight of an unsaturated cyanide compound and 55 to 55% by weight of an aromatic vinyl compound in the presence of
85% by weight of a monomer mixture or 80% to 100% by weight of an alkyl methacrylate and 0% to 20% by weight of an alkyl acrylate
Graft copolymer (A) (B) Conjugated diene rubbery polymer (b) latex
In the presence of 65% by weight (as solid content), a gel content of 70 to 95% by weight of a monomer mixture composed of an alkyl acrylate and a copolymerizable monomer is obtained by seed polymerization. 20 to 80 parts by weight (as solid content) of a composite rubber-like polymer (b ') latex of at least% by weight
Graft copolymer (B) (C) obtained by graft-polymerizing 20 to 80 parts by weight of a monomer mixture comprising 15 to 45% by weight of an unsaturated cyanide compound and 55 to 85% by weight of an aromatic vinyl compound in the presence of ) Polyorganosiloxane rubbery polymer (b-
2) 35 to 95% by weight of a monomer mixture composed of an alkyl acrylate and a monomer copolymerizable therewith is seed-polymerized in the presence of 5 to 65% by weight (as solid content) of latex. Unsaturated cyanide compounds 15 to 4 in the presence of 20 to 80 parts by weight (as solid content) of a composite rubbery polymer (c ') latex having a gel content of 70% by weight or more.
Graft copolymer (C) obtained by graft polymerizing 20 to 80 parts by weight of a monomer mixture comprising 5% by weight and 55 to 85% by weight of an aromatic vinyl compound (II) 70 to 100% by weight of a conjugated diene; An acid group-containing copolymer is added to a conjugated diene rubbery copolymer (d) latex having an average particle size of 0.03 to 0.2 μm obtained by emulsion polymerization of 0 to 30% by weight of a copolymerizable monomer. An enlarged rubbery copolymer (d ') latex obtained by adding a metal salt of an oxygen acid (ii) to the combined latex (i) or the acid group-containing copolymer latex as required,
In the presence of 70 parts by weight (as solid content), 15 to 45% by weight of an unsaturated cyanide compound and 55 to 8% of an aromatic vinyl compound
A graft copolymer (II) obtained by graft polymerization of a monomer mixture consisting of 5% by weight. (III) A hard thermoplastic resin (III) obtained by copolymerizing two or more monomers selected from unsaturated cyanide compounds, aromatic vinyl compounds, unsaturated ester compounds and maleimide compounds.

Hereinafter, the present invention will be described in more detail. Alkyl acrylate rubbery copolymer (a) used for graft copolymer (A) used in the present invention
Is obtained by emulsion-copolymerizing 35 to 85% by weight of an acrylic acid alkyl ester, 15 to 65% by weight of a conjugated diene and 0 to 20% by weight of a monomer copolymerizable therewith. The alkyl acrylate used herein refers to an alkyl acrylate having 1 to 12 carbon atoms in an alkyl group or an aromatic acrylate having a benzene ring such as a phenyl group or a benzyl group. Examples thereof include n-butyl acrylate, 2-ethylhexyl acrylate, and ethyl acrylate, and one or more kinds can be used. If the amount is 30% by weight or less, an acrylate compound having a functional group such as glycidyl acrylate, 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate, or dimethylaminoethyl acrylate is used in combination with the above. It is also possible.

Preferred examples of the conjugated diene include 1,3-butadiene, isoprene, chloroprene and the like, and it is particularly preferable to use 1,3-butadiene. Examples of the monomer copolymerizable with the alkyl acrylate include allyl acrylate, allyl methacrylate, divinylbenzene, ethylene glycol dimethacrylate, butylene glycol diacrylate, triallyl cyanurate, triallyl isocyanurate, and trimethylolpropanetriene. Polyfunctional monomers such as acrylate and pentaerythritol tetraacrylate; unsaturated cyanides such as acrylonitrile; aromatic vinyl compounds such as styrene; alkyl methacrylates such as methyl methacrylate; and unsaturated carboxylic compounds such as methacrylic acid. And the like, and one kind or two or more kinds can be used. When the amount of the conjugated diene is small, one or more polyfunctional monomers are usually used.

The proportion of the alkyl acrylate in the acrylic acrylate rubber-like copolymer (a) is determined from the balance between performance of impact strength and chemical resistance.
5 to 85% by weight. If the amount is less than 35% by weight, the chemical resistance of the resin composition becomes poor, which is not preferable. If the amount exceeds 85% by weight, the impact strength of the resin composition is impaired, which is not preferable. Also, from the viewpoint of impact strength development, the gel content of the rubbery copolymer (a) is 70%.
It is necessary to exceed by weight.

The average particle size of the rubbery copolymer (a) is as follows:
The range of 0.03 to 0.2 μm is preferred. The rubbery copolymer (a) is an acid group-containing copolymer latex (i)
Alternatively, if necessary, a metal salt of oxygen acid (ii) is added to the acid group-containing copolymer latex (i),
0.15 to 0.5 μm, preferably 0.2 to 0.4 μm
Bloated to the size of. By using the enlargement operation, a rubber having a large particle diameter can be stably obtained in a short time. It is preferable that all the rubbery copolymers (a) become the enlarged rubbery copolymers (a ′) by the enlargement operation, but such cases are usually rare. However, even if a small amount of unexpanded particles (expanded rubbery copolymer (a)) remain, the physical properties of the molded product obtained from the resin composition of the present invention can be at a level with almost no problem. Can be

The acid group-containing copolymer latex (i) is selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, cinnamic acid, sorbic acid and p-styrenesulfonic acid. 3 to 40% by weight of one or more unsaturated acids, wherein the alkyl group has 1 to 12 carbon atoms.
97 to 35% by weight of at least one alkyl acrylate and 0 to 40% by weight of another monomer copolymerizable therewith can be obtained by emulsion polymerization. Among these, a copolymer of methacrylic acid and butyl acrylate is a good example.

The metal salt of an oxyacid used in the present invention (ii)
Is an alkali metal salt or an alkaline earth metal salt of an oxyacid centered on an element selected from the elements belonging to the second and third periods of Groups IIIA to VIA in the Periodic Table of the Elements. ,
Zinc, one or more oxyacid salts selected from nickel and aluminum salts, specifically, salts of sulfuric acid, nitric acid, phosphoric acid and potassium, sodium, magnesium, calcium, zinc, aluminum, Preferable examples include potassium sulfate, sodium sulfate, and sodium phosphate. The metal salt (ii) of the oxyacid is added in the form of an aqueous solution.

[0011] The amount of the above-mentioned thickening agent is based on 100 parts by weight (as solid content) of the alkyl acrylate-based rubbery copolymer (a) and 0.1% of the acid group-containing copolymer latex (i). 5 to 8 parts by weight (as a solid content), and when the metal salt of oxyacid (ii) is used in combination, an acid group-containing copolymer latex (i) 0.5 to 5 parts by weight (as a solid content)
And 0.05 to 2 parts by weight (as solid content) of an aqueous solution of a metal salt of oxyacid (ii).

The thus obtained enlarged rubbery copolymer (a ') latex is subsequently subjected to graft polymerization. The graft polymerization is performed using the enlarged rubbery copolymer (a ')
In the presence of 20 to 80 parts by weight of latex (as solid content), a monomer mixture comprising 15 to 45% by weight of an unsaturated cyanide compound and 55 to 85% by weight of an aromatic vinyl compound or 80 to 100% by weight of a methacrylic acid alkyl ester % And a monomer mixture comprising 20 to 80 parts by weight of an acrylic acid alkyl ester in an amount of 0 to 20% by weight. The monomer used for graft polymerization is 2
If the amount is less than 0 parts by weight, coarse particles may be formed in the coagulation step after the graft polymerization or the appearance of the resin composition may be impaired, which is not preferable. If the amount exceeds 80 parts by weight, a large amount of an emulsifier is required to stably carry out graft polymerization, which is not preferable because it causes coloring during the thermal processing of the resin composition.

Examples of the unsaturated cyanide compound used for the graft polymerization include acrylonitrile, methacrylonitrile, ethacrylonitrile, maleonitrile, fumaronitrile and the like, and acrylonitrile is preferably used. As the aromatic vinyl compound, styrene,
α-methylstyrene, o-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-ethylstyrene, p-tert-butylstyrene, halogenated styrene and the like are exemplified, and styrene or α-methylstyrene is used. Is preferred.

The proportion of the unsaturated cyanide compound to the aromatic vinyl compound used is 15 to 45% by weight of the unsaturated cyanide compound and 55 to 85% by weight of the aromatic vinyl compound, more preferably 20 to 35% by weight of the unsaturated cyanide compound. % By weight and aromatics from 65 to 80% by weight. 15 unsaturated cyanide
When the amount is less than 45% by weight, the impact strength is poor, so that it is not preferable. When the amount is more than 45% by weight, the moldability is deteriorated and the thermal coloring is deteriorated.

[0015] The alkyl methacrylate used for the graft polymerization refers to an alkyl group having 1 to 1 carbon atoms.
8 is a methacrylic acid ester such as a chain or cyclic alkyl group, phenyl group, benzyl group, glycidyl group, 2-hydroxyethyl group, and one or more kinds thereof can be used. Preferred is methyl methacrylate.

For the purpose of improving the thermal decomposability at the time of molding, the alkyl methacrylate can be replaced with the alkyl acrylate at a ratio of 20% by weight or less of 100% by weight of the alkyl methacrylate used for the graft polymerization. Preferred examples of the alkyl acrylate used here include methyl acrylate and ethyl acrylate.

As the graft polymerization method, a known emulsion polymerization method can be employed. A method in which monomers are charged in a lump and then polymerized, a method in which a part is charged first, and a method in which the remaining portion is dropped, and a method in which polymerization is performed as needed while dropping the entire amount, can be performed in one or more stages. At this time, the type and composition ratio of the monomer in each stage can be changed. The obtained graft copolymer latex is coagulated by a known method, and is obtained as a graft copolymer (A) through steps such as dehydration, washing, and drying.

The composite rubbery polymer (b ') latex used for the graft copolymer (B) used in the present invention is a conjugated diene rubbery polymer (b) latex 5
It is obtained by subjecting 35 to 95% by weight of a monomer mixture composed of an alkyl acrylate and a monomer copolymerizable therewith to seed polymerization in the presence of 65% by weight (as solid content). If the amount of the conjugated diene-based rubbery polymer (b) used is outside the above range, the resin composition has poor impact strength development or chemical resistance, which is not preferable.

The conjugated diene rubbery polymer (b) used herein is a copolymer comprising 50% by weight or more of a conjugated diene and 50% by weight or less of a monomer copolymerizable therewith. Examples of the conjugated diene include 1,3-butadiene, isoprene and chloroprene, and examples of the copolymerizable monomer include an unsaturated cyanide compound such as acrylonitrile and an aromatic vinyl compound such as styrene. Preferred examples of the conjugated diene rubbery polymer include polybutadiene,
Acrylonitrile-butadiene copolymer rubber, styrene-
Butadiene copolymer rubber is mentioned, and polybutadiene is most preferred. These are obtained by emulsion polymerization.

The conjugated diene rubbery polymer (b) latex is preferably large particles having an average particle diameter of 0.2 to 1.0 μm. Such large-particle rubber may be obtained over a long period of time by several stages of seed polymerization, but is preferably obtained by an enlargement operation. That is, by adding an acid group-containing copolymer latex (i) used in the graft copolymer (A) and, if necessary, a metal salt of an oxyacid to a base rubber latex of 0.03 to 0.15 μm. , And can be obtained stably and efficiently. In order to obtain an enlarged rubber having large particles as described above, it is necessary to adjust the pH of the base rubber latex to 9 or more and use an acid group-containing copolymer latex having a high unsaturated acid content. In the bloating operation, it is rare that all the base rubber becomes the bloated rubber, and usually a certain amount of unbloated base rubber remains. Therefore, the enlarged rubber has a particle size distribution of two dispersions. The preferred average particle diameter range of the conjugated diene rubber is 0.2 to 1.0 μm, but when focusing on only the large particle diameter side of the enlarged rubber excluding the unexpanded base rubber, the average particle diameter is 0%. 0.4 to 1.2 μm is a preferable range.

The composite rubbery polymer (b ') latex is
It can be obtained by seed polymerization of a monomer mixture comprising an alkyl acrylate and a monomer copolymerizable therewith in the presence of the conjugated diene rubbery polymer (b) latex.

Examples of the alkyl acrylate include those similar to those used in the graft copolymer (A). Monomers copolymerizable with the alkyl acrylate include monofunctional monomers such as acrylonitrile, styrene, n-hexyl methacrylate, 2-ethylhexyl methacrylate, and n-lauryl methacrylate, and the following crosslinking agents and grafts. Examples include polyfunctional monomers such as crosslinkers. Among them, it is preferable to use a cross-linking agent and a graft cross-linking agent in combination in terms of impact strength.

Examples of the crosslinking agent include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, and 1,4-butylene glycol dimethacrylate. Examples of the grafting agent include allyl methacrylate. , Triallyl cyanurate, triallyl isocyanurate and the like. These crosslinking agents and graft crossing agents may be used alone or in combination of two or more.

The total amount of the crosslinking agent and the graft crosslinking agent used is 0.01 to 10% by weight in the monomer mixture containing alkyl acrylate as a main component, and the monofunctional monomer is 0 to 10% by weight. Preferably it is 30% by weight.

Preferred examples of the monomer mixture used for seed polymerization include butyl acrylate of 95 to 99.95% by weight.
And a mixture consisting of 0.02 to 4.97% by weight of a crosslinking agent and 0.03 to 4.98% by weight of a graft crosslinking agent (total 1).
00% by weight).

The gel content of the composite rubber-like polymer (b ') must be more than 70% by weight from the viewpoint of exhibiting impact strength.

The method of seed polymerization of a monomer mixture containing an alkyl acrylate as a main component in the presence of a conjugated diene rubber-like polymer (b) latex is a method of dropping the monomer mixture while optionally polymerizing. A method in which a monomer mixture is previously impregnated into a base rubber-like polymer and then polymerized by adding an initiator and the like, and an operation of impregnating the monomer mixture and then polymerizing is performed on the monomer mixture in each stage. A method in which the composition is repeated several times while changing the composition may be used. Among these, a method of impregnating the monomer mixture in advance with the base rubber-like polymer and then polymerizing the mixture is preferable. In the case of seed polymerization, an emulsifier may be newly added for the purpose of improving polymerization stability, but the amount is preferably as small as possible.

As a result of the seed polymerization, in some cases, the conjugated diene-based rubber-like polymer (b) as the core is not seeded, and the rubber-like polymer consisting only of the monomer mixture containing alkyl acrylate as a main component is not obtained. Although coalescence may be formed as a by-product, there is no problem in the performance intended by the present invention. However, if the amount is large, the appearance of a molded article using the resin composition may be impaired.Therefore, the amount of the rubbery polymer composed of only a monomer mixture mainly composed of alkyl acrylate by-produced is limited. It is preferred to minimize as much as possible.

The resulting composite rubbery polymer (b ') latex is subsequently subjected to graft polymerization. The graft polymerization is performed using a composite rubber-like polymer (b ') latex 20 to 8
In the presence of 0 parts by weight (as solid content), 15 to 45% by weight of an unsaturated cyanide compound and 55 to 85% of an aromatic vinyl compound
It is carried out by graft polymerizing 20 to 80 parts by weight of a monomer mixture consisting of% by weight.

The types and amounts of the unsaturated cyanide compound and the aromatic vinyl compound, which are monomers used for the graft polymerization, and the method of the graft polymerization are the same as those of the graft copolymer (A). The obtained latex is obtained as a graft copolymer (B) through steps such as coagulation, dehydration, washing, and drying.

The polyorganosiloxane-based rubbery polymer (c) used for the graft copolymer (C) used in the present invention comprises an organosiloxane, a crosslinking agent and, if necessary, a graft crossing agent. It is a rubbery polymer. Examples of the organosiloxane include various cyclic members having three or more membered rings, and preferably a three- to six-membered ring. For example, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane, octaphenylcyclotetrasiloxane, and the like, These may be used alone or as a mixture of two or more.

Examples of the crosslinking agent include trifunctional or tetrafunctional silane crosslinking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane,
Tetrabutoxysilane or the like is used. Particularly, a tetrafunctional crosslinking agent is preferable, and among them, tetraethoxysilane is particularly preferable. The amount of the crosslinking agent used is 0.1 to 30% by weight in the polyorganosiloxane rubbery polymer (b).

As the graft crossing agent, the following formula: CH ₂ ＣC (R ² ) —COO— (CH ₂ ) _p —SiR ¹ _n O _{(3-n) / 2-} (I) CH ₂ ＣＨCH— ^{_{SiR 1 n O (3-n}} ) / 2 --- (II) HS- (CH 2) p -SiR 1 n O (3-n) / 2 --- (III) ( the formulas R ¹ is methyl A group, an ethyl group, a propyl group or a phenyl group, R ² is a hydrogen atom or a methyl group, n is 0,
1 or 2 and p represents a number of 1 to 6. A compound capable of forming the unit represented by the formula (1) is used. (Meth) acryloyloxysiloxane capable of forming the unit of the formula (I) has a high grafting efficiency and can form an effective graft chain, and is advantageous in terms of the development of impact resistance. Note that methacryloyloxysiloxane is particularly preferable as a unit capable of forming the unit of the formula (I). Specific examples of methacryloyloxysiloxane include β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropylmethoxydimethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-
Examples thereof include methacryloyloxypropylethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane, and δ-methacryloyloxybutyldiethoxymethylsilane. The amount of the grafting agent used is 0 to 0 in the polyorganosiloxane rubbery polymer (c).
10% by weight.

The average particle diameter of the polyorganosiloxane rubber-like polymer (c) latex is 0.08 to 0.6 μm.
Is preferably within the range. Average particle size 0.08μ
When the average particle diameter exceeds 0.6 μm, the impact resistance of the molded article from the obtained resin composition deteriorates, and when the average particle diameter exceeds 0.6 μm, the impact resistance of the molded article from the obtained resin composition deteriorates. The appearance of the molding surface deteriorates, which is not preferable.

The preparation of the polyorganosiloxane rubbery polymer (c) latex is described, for example, in US Pat.
Nos. 920 and 3294725 can be used, but a mixed solution of an organosiloxane and a crosslinking agent and, if necessary, a graft-linking agent can be mixed with an alkylbenzenesulfonic acid, an alkylsulfonic acid, or the like. It is preferable to produce by a method of shear-mixing with water using a homogenizer or the like in the presence of a sulfonic acid-based emulsifier. Alkylbenzene sulfonic acid is suitable because it acts as an emulsifier for the organosiloxane and also serves as a polymerization initiator. At this time, it is preferable to use a metal salt of an alkyl benzene sulfonic acid, a metal salt of an alkyl sulfonic acid or the like in combination, since this is effective for stably maintaining the polymer during graft polymerization.

The polyorganosiloxane rubbery polymer (c) latex is neutralized by adding an aqueous alkali solution such as sodium hydroxide, potassium hydroxide, sodium carbonate, and the like, and then contains the following alkyl acrylate as a main component. For the seed polymerization of the monomer.

The composite rubbery polymer (c ') latex is
In the presence of a polyorganosiloxane-based rubber-like polymer (c) latex of 5 to 65% by weight (as solid content), a monomer mixture of an acrylic acid alkyl ester and a monomer copolymerizable therewith is used. It is obtained by subjecting 95% by weight to seed polymerization.

The types and amounts of the alkyl acrylate and the monomer copolymerizable therewith, which are used in the seed polymerization,
The method of seed polymerization is the same as that described in the description of the graft copolymer (B). In addition, the composite rubber-like polymer (c ′) needs to have a gel content of more than 70% by weight from the viewpoint of exhibiting impact strength.

The obtained composite rubbery polymer (c ') latex is subsequently subjected to graft polymerization. The graft polymerization is performed using a composite rubber-like polymer (c ') latex 20 to 8
In the presence of 0 parts by weight (as solid content), 15 to 45% by weight of an unsaturated cyanide compound and 55 to 85% of an aromatic vinyl compound
It is carried out by graft polymerizing 20 to 80 parts by weight of a monomer mixture consisting of% by weight.

The types and amounts of the unsaturated cyanogen compound and the aromatic vinyl compound, which are monomers used for the graft polymerization, and the method of the graft polymerization are the same as those of the graft copolymer (A). The obtained latex is obtained as a graft copolymer (C) through processes such as coagulation, dehydration, washing, and drying.

The conjugated diene rubbery copolymer (d) latex to be used for the graft copolymer (II) is composed of 70 to 100% by weight of a conjugated diene and 0 to 3 of a monomer copolymerizable therewith.
0% by weight and emulsion polymerization. The conjugated diene used herein includes 1,3-butadiene, isoprene,
Chloroprene is mentioned as a good example, and is preferably used in an amount of 70% by weight or more from the viewpoint of exhibiting impact strength. Also,
Examples of the monomer copolymerizable with the conjugated diene include unsaturated cyanide compounds such as acrylonitrile, aromatic vinyl compounds such as styrene, alkyl methacrylates such as methyl methacrylate, and unsaturated carboxylic compounds such as methacrylic acid. Monomers can be used, and one or more kinds can be used. Preferred examples of the conjugated diene rubber polymer (d) include polybutadiene rubber, acrylonitrile-butadiene copolymer rubber, and styrene-butadiene copolymer rubber.

The average particle diameter of the conjugated diene rubbery copolymer (d) latex is preferably in the range of 0.03 to 0.2 μm. The conjugated diene-based rubbery copolymer (d) latex may be the kind and amount of an acid group-containing copolymer latex (i) described in the description of the graft copolymer (A) or, if necessary, a metal salt of oxyacid. By adding (ii), the thickness is reduced to 0.15 to 0.5 μm, preferably 0.2 to 0.5 μm.
It is enlarged to 4 μm. By this bloat operation,
An enlarged rubber-like copolymer (d ') latex having a large particle size suitable for impact strength development can be stably obtained in a short time.

The enlarged rubbery copolymer (d ') latex is subsequently subjected to graft polymerization. The graft polymerization is performed by using an enlarged rubber-like copolymer (d ') latex 20 to 8
In the presence of 0 parts by weight (as a solid content), the polymerization is performed by graft-polymerizing 20 to 80 parts by weight of one or more monomers selected from unsaturated cyanide compounds, aromatic vinyl compounds, and unsaturated ester compounds. .

Preferred examples of the monomer used for the graft polymerization include those described in the description of the graft copolymer (A). As for the graft polymerization method, a known emulsion polymerization method can be employed as in the case of the graft copolymer (A). The obtained graft copolymer latex is coagulated by a known method, and is obtained as a graft copolymer (II) through steps such as dehydration, washing, and drying.

The hard thermoplastic resin (II) used in the present invention
I) is obtained by copolymerizing two or more monomers selected from unsaturated cyanide compounds, aromatic vinyl compounds, unsaturated ester compounds and maleimide compounds.

Here, examples of the unsaturated cyanide compound include acrylonitrile, methacrylonitrile, ethacrylonitrile, maleonitrile, fumaronitrile, and the like. Of these, acrylonitrile is a preferred example.
The aromatic vinyl compound includes styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, p-ethylstyrene, p-tert-butylstyrene, 2,4
-Dimethylstyrene, halogenated styrene and the like, among which styrene and α-methylstyrene are preferred. Unsaturated ester compounds include methyl methacrylate, ethyl methacrylate, butyl methacrylate, phenyl methacrylate, benzyl methacrylate,
Examples thereof include methacrylate compounds such as glycidyl methacrylate and 2-hydroxyethyl methacrylate, and among them, methyl methacrylate is a preferred example. A maleimide compound is a maleimide having 1 carbon atom.
N-alkylmaleimides and N-phenylmaleimides substituted with an alkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, and a carbosyl group , Nitro group,
Examples include N-phenylmaleimide derivatives having one or more substituents selected from the group consisting of an amino group and a cyano group. Among these, N-phenylmaleimide and N-phenylmaleimide are exemplified.
A good example is cyclohexylmaleimide.

The hard thermoplastic resin (III) is composed of two or more of the monomers exemplified above, but preferably contains one or more unsaturated cyanide compounds. If specifically exemplified, an acrylonitrile-styrene copolymer, an acrylonitrile-α-methylstyrene copolymer, an acrylonitrile-styrene-methyl methacrylate copolymer,
Acrylonitrile-styrene-N-phenylmaleimide copolymer, acrylonitrile-α-methylstyrene-N
-Phenylmaleimide copolymer and the like. The hard thermoplastic resin (III) may be used alone or in combination of two or more. There is no particular limitation on the method for producing the hard thermoplastic resin (III), but it is preferable to employ a method that can best express the performance of the resin.

More specifically, the following are preferred. A copolymer comprising 20 to 45% by weight, more preferably 25 to 40% by weight, of acrylonitrile and 55 to 80% by weight, more preferably 60 to 75% by weight, of styrene or α-methylstyrene. It is composed of 10 to 40% by weight of acrylonitrile, 30 to 50% by weight of styrene and 30 to 50% by weight of methyl methacrylate (total 100% by weight).
Copolymer. A copolymer comprising 10 to 40% by weight of acrylonitrile, 40 to 80% by weight of styrene, and 5 to 40% by weight of N-phenylmaleimide or N-cyclohexylmaleimide.

The hard thermoplastic resin (III) may be used alone or in combination of two or more. There is no particular limitation on the method for producing the hard thermoplastic resin (III), but it is preferable to employ a method that can exhibit the best performance of the resin.

The thermoplastic resin composition of the present invention comprises one or more graft copolymers selected from the group consisting of a graft copolymer (A), a graft copolymer (B) and a graft copolymer (C). It is obtained by blending I) and the graft copolymer (II) as essential components and, if necessary, a hard thermoplastic resin (III). The graft copolymer (I) is essential for developing the chemical resistance of the resin composition. Further, the graft copolymer (II) is indispensable in terms of the impact strength of the resin composition.

The blending ratio of the graft copolymer (I), the graft copolymer (II) and the hard thermoplastic resin (III) is such that the proportion of the rubbery polymer in the thermoplastic resin composition is in a preferable range. It is decided as follows. That is, the proportion of the rubber-like polymer in 100% by weight of the thermoplastic resin composition is 15 to 30% by weight, and more preferably 20 to 28%.
It is blended so that the ratio of the alkyl acrylate unit constituting the rubber-like polymer to 100% by weight of the rubber-like polymer is 30 to 85% by weight.

If the proportion of the rubbery polymer in the thermoplastic resin composition is less than 15% by weight, the impact strength is poor, and if it exceeds 30% by weight, the surface hardness and rigidity will be poor. It is not preferable because the use purpose is restricted by the decrease of. Further, 30% by weight of alkyl acrylate units forming the rubbery polymer are contained.
If less than 85, it is not preferable because of poor chemical resistance.
If the content is more than 10% by weight, it will be difficult to obtain excellent impact strength, which is not preferable.

The rubbery weight occupying the specific resin composition according to the present invention can be obtained from the graft copolymer (I) alone or the resin composition comprising the graft copolymer (I) and the hard thermoplastic resin (III). It is possible to obtain a thermoplastic resin composition that satisfies the combined ratio and the alkyl acrylate unit ratio in the rubbery polymer. However,
Although these thermoplastic resin compositions have excellent chemical resistance, their impact strength developability is slightly inferior, and their use is restricted. In order to obtain excellent impact strength, it is necessary to increase the amount of the rubbery polymer used, which is not preferable in terms of surface hardness and rigidity as described in detail above. Therefore, in order to obtain excellent impact strength development properties, it is preferable to blend the graft copolymer (II) in an amount of 5 parts by weight or more in order to sufficiently obtain the effect of blending the graft copolymer (II). .

In order to mix the graft copolymer (I), the graft copolymer (II) and the hard thermoplastic resin (III), they are usually mixed with a V-type blender, a Henschel mixer or the like. Depending on the type, various stabilizers, lubricants, plasticizers, release agents, dyes, pigments, inorganic fillers, fine metal particles, antistatic agents, and the like can be added. These mixtures are melt-kneaded using a mixing roll, a screw extruder, or the like, and then pelletized by a pelletizer.

[0055]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. In the following Examples and Comparative Examples, "parts" indicates parts by weight. The average particle size of the rubber-like polymer latex was measured from an image taken with a transmission electron microscope after immobilization with osmium tetroxide or the like. The gel content of the rubbery polymer was determined as follows. After the dried rubber-like polymer was immersed in toluene at 30 ° C. for 24 hours, the material remaining on the 200-mesh wire net was dried to obtain a gel. I asked.

Synthesis of alkyl acrylate -based rubbery copolymer (a-1) n-butyl acrylate 50 parts 1,3-butadiene 50 parts diisopropylbenzene hydroperoxide 0.2 parts tert-dodecyl mercaptan 0.4 parts Potassium oleate 1 part Sodium N-lauroyl sarcosinate 1 part Rongalit 0.5 part Distilled water 195 parts Of the above compositions, except for 1,3-butadiene, the oxygen contained therein is replaced with nitrogen. The state was such that the reaction was not substantially inhibited. After that, all substances are
The mixture was charged in a 0-liter autoclave, and heated to 55 ° C. with vigorous stirring. Add the following mixture to this,
The polymerization was carried out at 55 ° C. for 8 hours. As a result, an acrylic acid alkyl ester-based rubbery copolymer (a-1) latex having a monomer conversion rate of 99% and a particle diameter of 0.07 μm was obtained. The gel content was found to be 82% by weight. Disodium ethylenediaminetetraacetate dihydrate 0.012 parts Ferrous sulfate heptahydrate 0.004 parts Distilled water 5 parts

Synthesis of alkyl acrylate rubber-based copolymer (a-2) 99 parts n-butyl acrylate 0.8 parts allyl methacrylate 0.2 parts divinylbenzene 0.02 parts diisopropylbenzene hydroperoxide 0.02 parts potassium oleate 1.2 parts Sodium N-lauroyl sarcosinate 0.8 part Rongalit 0.4 part Distilled water 198 parts The above composition is charged into a 50-liter polymerization vessel, and oxygen in the vessel is completely removed with nitrogen, and then up to 50 ° C. The temperature rose. The following mixture was added thereto, and polymerization was carried out at 50 ° C. for 5 hours. As a result, an alkyl acrylate rubber-like copolymer (a-2) latex having a monomer conversion rate of 98%, a particle diameter of 0.14 μm, and a gel content of 78% by weight was obtained. Disodium ethylenediaminetetraacetate dihydrate 0.000015 parts Ferrous sulfate heptahydrate 0.000005 parts Distilled water 2 parts

Synthesis of conjugated diene rubbery copolymer (d-1) 1,3-butadiene 100 parts Diisopropylbenzene hydroperoxide 0.2 parts tert-dodecylmercaptan 0.5 parts Potassium oleate 1 part Disproportionation Potassium rosinate 1 part Dextrose 0.3 part Anhydrous sodium sulfate 0.18 part Sodium hydroxide 0.02 part Distilled water 195 parts and sodium pyrophosphate decahydrate 0.5 part Ferrous sulfate heptahydrate 0. 005 parts distilled water 5 parts The above composition was polymerized for 9 hours by the same operation as in the synthesis of the alkyl acrylate rubber-based polymer (a-1). As a result, a conjugated diene rubbery copolymer (d-1) latex having a monomer conversion of 97%, a particle diameter of 0.08 μm, and a gel content of 80% by weight was obtained.

Synthesis of acid group-containing copolymer (i-1) latex Potassium oleate 2.5 parts Potassium dioctyl sulfosuccinate 2.5 parts Disodium ethylenediaminetetraacetate dihydrate 0.012 parts Ferrous sulfate 7-hydrate 0.004 parts Rongalit 0.5 parts Distilled water 200 parts The above composition was charged into a 5-liter glass separable flask, the oxygen in the system was replaced with nitrogen while stirring, and the temperature was raised to 70 ° C. . The following monomer mixture which had been subjected to nitrogen substitution was added dropwise thereto over 4 hours to carry out polymerization. 85 parts of n-butyl acrylate 15 parts of methacrylic acid 0.5 part of cumene hydroperoxide Then, the mixture is kept at 70 ° C. for 1 hour to obtain an acid group-containing copolymer (i-1) latex having a monomer conversion rate of 97%. Obtained.

Synthesis of Acid -Group-Containing Copolymer (i-2) Synthesis of acid-group-containing copolymer (i-1) latex except that the composition of the monomer mixture to be dropped was changed as follows. Polymerization was performed by the same operation. As a result, an acid group-containing copolymer (i-2) latex having a monomer conversion of 96% was obtained. n-butyl acrylate 80 parts methacrylic acid 20 parts cumene hydroperoxide 0.5 part

Synthetic rubbery copolymer (a-1) of graft copolymer (A-1) 50 parts (as solid content) latex were charged into a 20-liter separable flask,
After stirring, 0.4 part of a 10% aqueous solution of sodium sulfate was added as a solid content, and then the acid group-containing copolymer (i-1) was further added.
1.3 parts of latex was added as a solid content, and the mixture was kept for 30 minutes while stirring, and then 95 parts of distilled water was added.
As a result, an enlarged rubber-like copolymer (a'-1) latex having an average particle diameter of 0.27 µm was obtained. Sodium N-lauroyl sarcosinate 1.25 parts Disodium ethylenediaminetetraacetate dihydrate 0.003 part Ferrous sulfate heptahydrate 0.001 part Rongalite 0.5 part Enlarged rubbery copolymer (a ' -1) The above composition was added to latex, and the temperature was raised to 75 ° C. while stirring. Graft polymerization was performed by dripping the following monomer mixture over 120 minutes. Acrylonitrile 15 parts Styrene 35 parts tert-butyl hydroperoxide 0.3 parts n-octylmercaptan 0.1 parts After the dropping of the monomer mixture was completed, the mixture was kept for 1 hour to obtain a graft copolymer latex. This graft copolymer latex was put into a dilute aqueous sulfuric acid solution to coagulate, and then dehydrated, washed and dried to obtain a graft copolymer (A-1).

Synthesis of Graft Copolymer (A-2) The synthesis was carried out in the same manner as in the synthesis of the graft copolymer (A-1) up to obtaining an enlarged rubbery copolymer. Enlarged rubbery copolymer (a'-1) latex (as solid content) 60 parts Sodium N-lauroyl sarcosinate 0.75 parts Disodium ethylenediaminetetraacetate dihydrate 0.0015 parts Ferrous sulfate-7 0.0005 parts of water salt 0.4 parts of Rongalit The above composition was charged into a 20-liter separable flask, heated to 75 ° C. with stirring, and then the following monomer mixture was dropped in over 90 minutes. Graft polymerization was performed. Methyl methacrylate 36 parts Ethyl acrylate 4 parts Cumene hydroperoxide 0.15 parts n-octyl mercaptan 0.05 parts After the dropping of the monomer mixture was completed, the mixture was kept for 1 hour to obtain a graft copolymer latex. This graft copolymer latex was poured into a dilute sulfuric acid aqueous solution to coagulate, and then dehydrated, washed, and dried to obtain a graft copolymer (A-2).

A rubbery copolymer (a-2) is used as a synthetic rubbery polymer of the graft copolymer (A-3) , and an acid group-containing copolymer is used as a thickening agent used in a thickening operation. (I-1) Graft copolymer (A) except that acid group-containing copolymer (i-2) was used instead of latex.
-1), and the graft copolymer (A-
3) was obtained. The enlarged rubbery copolymer (a'-
The average particle size of 2) was 0.31 μm.

Synthesis of Composite Rubbery Polymer (b'-1) A rubbery copolymer (d) was placed in a 20-liter separable flask.
-1) Charge 20 parts of latex in solid content. To this, an acid group-containing copolymer (i-2) latex was added in an amount of 0.5 part by solid content with stirring, and after maintaining for 30 minutes, 160 parts of distilled water was added to perform an enlargement operation. .
As a result, an enlarged rubbery copolymer having an average particle diameter of 0.37 μm was obtained. n-butyl acrylate 79.55 parts allyl methacrylate 0.3 part ethylene glycol dimethacrylate 0.25 part tert-butyl hydroperoxide 0.2 part
Dissolve 0.5 part of sodium N-lauroyl sarcosinate and replace the system with nitrogen to remove oxygen. Internal temperature 45
At the time when the temperature was raised to ° C, the following composition was introduced. Rongalit 0.5 part Ferrous sulfate heptahydrate 0.0003 part Disodium ethylenediaminetetraacetate dihydrate 0.0009 part Distilled water 10 parts As a result, polymerization started and the internal temperature rose to about 70 ° C.
Thereafter, the mixture was held while stirring at 75 ° C. for 90 minutes to obtain a composite rubber-like polymer (b′-1) latex. The gel content was determined to be 84% by weight.

Synthesis of Composite Rubbery Polymer (b'-2) In the synthesis of the composite rubbery polymer (b'-1), 0.2 part of n-octyl mercaptan was added to a monomer mixture used for seed polymerization. Except for the addition, the composite rubbery polymer (b'-
It was synthesized in the same manner as in 1). The gel content of the obtained composite rubbery polymer (b′-2) was 47% by weight.

Synthetic composite rubbery polymer (b'-1) latex (as solid content ) of graft copolymer (B-1 ) 50 parts Sodium N-lauroyl sarcosinate 1.2 parts Rongalit 0.4 parts Sulfuric acid Ferrous heptahydrate 0.001 part Disodium ethylenediaminetetraacetate dihydrate 0.003 part Distilled water 100 parts The above composition was charged in a 20-liter separable flask, and the temperature was raised to 75 ° C. while stirring. . Graft polymerization was performed by dripping the following monomer mixture over 120 minutes. Acrylonitrile 15 parts Styrene 35 parts tert-butyl hydroperoxide 0.3 parts n-octyl mercaptan 0.1 parts After completion of the dropping of the monomer mixture, the mixture is kept under stirring for another 1 hour, whereby the graft copolymer latex is obtained. Obtained. This graft copolymer latex was poured into a dilute aqueous sulfuric acid solution to coagulate, and then dehydrated, washed, and dried to obtain a powdery graft copolymer (B-1).

Synthesis of Graft Copolymer (B-2) In the synthesis of the graft copolymer (B-1), the composite rubber-like polymer (b'-) was used instead of the composite rubber-like polymer (b'-1). Except that 2) was used, the graft copolymer (B
-1), the graft copolymer (B-
2) was obtained.

Synthesis of Composite Rubbery Polymer (c'-1) Dodecylbenzenesulfonic acid 1 part Sodium dodecylbenzenesulfonate 1 part Distilled water 200 parts To the above composition, a siloxane mixture having the following composition was added. The mixture was preliminarily mixed at 10,000 rpm and emulsified and dispersed with a homogenizer at a pressure of 300 kg / cm ² to obtain an organosiloxane latex. Tetraethoxysilane 1.0 part γ-methacryloyloxypropyldimethoxymethylsilane 0.25 part Octamethylcyclotetrasiloxane 48.75 parts This mixture is transferred to a 20-liter separable flask and heated at 80 ° C. for 5 hours with stirring. Then, after standing at 20 ° C. for 48 hours, the pH of this latex was neutralized to 7.5 with an aqueous sodium hydroxide solution to obtain a polyorganosiloxane rubber-like polymer (c-1) latex. The average particle size was 0.16 μm. To this, 70 parts of distilled water was added, and while stirring, the following monomer mixture was added and mixed well. n-butyl acrylate 48.6 parts Allyl methacrylate 1.05 parts Ethylene glycol dimethacrylate 0.35 parts tert-butyl hydroperoxide 0.3 parts After the system is purged with nitrogen to remove oxygen, the internal temperature is raised to 50 ° C. The polymerization was started by adding the following mixture. Rongalit 0.3 part Ferrous sulfate heptahydrate 0.002 part Disodium ethylenediaminetetraacetate dihydrate 0.006 part Distilled water 10 part As a result, the internal temperature was raised to about 65 ° C. Then 70
The composite rubber-like polymer (c'-2) latex was obtained by holding at 2 ° C. for 2 hours. Gel content is 95% by weight
Met.

Synthesis of Composite Rubbery Polymer (c'-2) In the synthesis of the composite rubbery polymer (c'-1), the monomer mixture to be subjected to seed polymerization was converted to 49.7 parts of n-butyl acrylate allyl methacrylate 0.35 parts tert-butyl hydroperoxide 0.3 parts n-octyl mercaptan 0.3 parts, except that the composite rubbery polymer (c′-
2) was obtained. The gel content was 63% by weight.

Synthetic composite rubber-like polymer (c'-1) latex (as solid content ) of graft copolymer (C-1 ) 60 parts Sodium dodecylbenzenesulfonate 0.3 parts Distilled water 80 parts , Into a 20-liter separable flask, and heated to 70 ° C. while stirring. To this, the following monomer mixture was dropped in over 60 minutes to perform graft polymerization. Acrylonitrile 12 parts Styrene 28 parts Cumene hydroperoxide 0.2 parts tert-dodecyl mercaptan 0.1 parts After the completion of dropping, the mixture was kept for 2 hours with stirring to obtain a graft copolymer latex. This graft copolymer latex was put into an aqueous calcium chloride solution to coagulate, dehydrated, washed and dried to obtain a powdery graft copolymer (C-1).

Synthesis of Graft Copolymer (C-2) In the synthesis of the graft copolymer (C-1), the composite rubber-like polymer (c'-) was used instead of the composite rubber-like polymer (c'-1). Except that 2) was used, a graft copolymer (C-2) was obtained in the same manner.

Synthesis of Graft Copolymer (D-1) Conjugated Diene Rubber Copolymer (d-1) Latex 60
Parts (as solid content) in a 20 liter separable flask and, while stirring, an acid group-containing copolymer (i-1)
The latex was added in an amount of 1.2 parts by solid content, kept for 30 minutes while stirring, and then 80 parts of distilled water was added. As a result, an enlarged rubber-like copolymer (d'-1) latex having an average particle size of 0.28 µm was obtained. Disproportionated potassium rosinate 0.4 part Sodium pyrophosphate decahydrate 0.02 part Ferrous sulfate heptahydrate 0.005 part Dextrose 0.4 part Sodium hydroxide 0.02 part The above composition was added to the polymer (d′-1) latex, and the temperature was raised to 60 ° C. with stirring. Graft polymerization was performed by dripping the following monomer mixture over 120 minutes. Acrylonitrile 12 parts Styrene 28 parts Cumene hydroperoxide 0.2 parts tert-dodecyl mercaptan 0.4 parts After the dropping of the monomer mixture was completed, the mixture was kept for 1 hour to obtain a graft copolymer latex. This graft copolymer latex was poured into a dilute aqueous sulfuric acid solution to coagulate, and then dehydrated, washed and dried to obtain a graft copolymer (D-1).

Synthetic acrylonitrile of hard thermoplastic resin (III-1) 30 parts Styrene 70 parts Azobisisobutyronitrile 0.15 parts tert-dodecylmercaptan 0.4 parts Calcium phosphate 0.5 parts Distilled water 150 parts The above composition Was charged into a 100 liter autoclave and stirred vigorously. After confirming the dispersion in the system, the temperature was raised to 75 ° C., and the polymerization was carried out for 3 hours. Thereafter, the temperature was raised to 110 ° C., and aging was performed for 30 minutes. After cooling, dehydration, washing and drying are performed to obtain a powdery hard thermoplastic resin (III-
1) was obtained.

Synthesis of rigid thermoplastic resin (III-2) Acrylonitrile 20 parts Styrene 40 parts Methyl methacrylate 40 parts Azobisisobutyronitrile 0.15 parts tert-Dodecyl mercaptan 0.2 parts Calcium phosphate 0.5 parts Distilled water 150 Part The above composition was polymerized by the same operation as in the synthesis of the hard thermoplastic resin (III-1) to obtain a powdered hard thermoplastic resin (III-2).

Synthesis of hard thermoplastic resin (III-3) Potassium oleate 3 parts Dextrose 0.5 part Ferrous sulfate heptahydrate 0.005 part Sodium pyrophosphate decahydrate 0.5 part Anhydrous sodium sulfate 0.15 parts Distilled water 200 parts Acrylonitrile 10 parts α-methylstyrene 70 parts tert-dodecyl mercaptan 0.1 parts The above composition was charged into a glass-lined 100-liter polymerization kettle, and heated to 60 ° C. with stirring. . After adding 0.5 part of cumene hydroperoxide to this,
Polymerization was carried out while 20 parts of acrylonitrile was added dropwise over 120 minutes. During this time, the internal temperature gradually increased to about 80
° C. Subsequently, the mixture was kept at 80 ° C. for 2 hours to obtain a copolymer latex. This latex was poured into an aqueous solution of magnesium sulfate, coagulated, dehydrated, washed, and dried to obtain a powdery hard thermoplastic resin (III-3).

Synthetic hard thermoplastic resin (III-4) 40 parts Styrene 10 parts Ethyl methyl ketone 10 parts The inside of a glass-lined 50 liter complete mixing type polymerization vessel was depressurized by a vacuum pump, and then nitrogen gas was introduced into the vessel. Was repeated several times, and then the mixture was charged into a vessel under a nitrogen atmosphere. After the temperature was raised to 100 ° C., the following mixture was dropped into the vessel over 60 minutes to perform solution polymerization. Acrylonitrile 20 parts N-phenylmaleimide 10 parts 1,1-dibutylperoxy-3,3,5-trimethylcyclohexane 0.07 parts Ethyl methyl ketone 20 parts -The residual amount of phenylmaleimide was greatly reduced.
Then, after the polymerization inhibitor was charged and rapidly cooled, the polymerization reaction product was quantitatively supplied to the devolatilizing extruder using a gear pump.
The copolymer was extruded in the form of a strand after removing the residual monomer and the organic solvent with a devolatilizing extruder. By treating this with a pelletizer, a pellet-shaped hard thermoplastic resin (III-4) was obtained.

Preparation of Thermoplastic Resin Composition Predetermined amounts of the graft copolymer (I), the graft copolymer (II) and the hard thermoplastic resin (III) were charged into a Henschel mixer together with the following substances and blended. ADK STAB Mark AO-20 (Asahi Denka) 0.3 parts ADK STAB Mark AO-412S (Asahi Denka) 0.3 parts Ethylene bis stearamide 1 part Magnesium stearate 0.3 parts Silicon oil SH200 (Toray Dow Corning Silicone) 0.03 parts The above mixture was melt-kneaded at 220 to 260 ° C. using a screw extruder, and then pelletized with a pelletizer. The pellets were formed into various test pieces using an injection molding machine or a press molding machine.

The obtained resin composition was evaluated by the following method. (1) Izod impact strength (Iz): ASTM D-2
It was measured at 56 (unit kg · cm / cm). (2) Rockwell hardness (R): ASTM D-785
(R scale). (3) Vicat softening temperature (VST): ISO R-30
6 (unit: ° C.). (4) Chemical resistance: A 35 × 120 mm specimen was cut out from a 2 mm thick press-formed plate of the resin composition, and the long diameter was 120 m.
m, attached to a 1/4 elliptical jig with a short diameter of 40 mm. After the chemical was applied to the surface of the test piece, it was covered with a polyethylene film and exposed to the chemical at 25 ° C. for 4 hours. For low-boiling chemicals, each jig was placed in a desiccator with an open / close cock, and exposed to the chemicals at 25 ° C. for 24 hours while being filled with the vapor of the chemical. After the exposure, the surface state of the specimen was observed, and the maximum stress-strain value at which no crack was generated was used as an index of chemical resistance. The following were used as chemicals.・ 1,1-Dichloro-1-fluoroethane ・ Brake oil (Toyota 2400G) ・ Wax remover (Yushiro Chemical ST-7) ・ Salad oil (Nisshin Oil) ・ Dioctyl phthalate

[0079]

[Table 1]

Description of the Table It can be seen that Examples 1-4 according to the present invention can provide thermoplastic resin compositions excellent in both impact strength development and chemical resistance. On the other hand, Comparative Example 1 is inferior in chemical resistance because the amount of the alkyl acrylate unit in the rubbery polymer is smaller than that of the present invention. In Comparative Example 2, since the rubbery polymer occupied more in the thermoplastic resin composition than in the present invention, the Rockwell hardness was lower than 80 and the surface was soft. Conversely, Comparative Example 3 is inferior in impact strength development due to a small amount of the rubbery polymer. In Comparative Example 4, although the amount of the rubbery polymer and the amount of the alkyl acrylate unit were in accordance with the present invention, general AAS (the rubbery polymer was a simple polybutyl acrylate rubber) was used as the graft copolymer (I). Since it is used, impact strength development is inferior. Comparative Examples 5 and 6 are graft copolymers (I) using a composite rubbery polymer having a low gel content.
Poor impact strength development. Heat-resistant hard thermoplastic resin (II
Even when I) is used, the thermoplastic resin composition using the graft copolymer (I) of the present invention has higher impact strength development property than Comparative Example 7 using the AAS resin. I understand.

[0081]

According to the present invention, there is provided a thermoplastic resin obtained by blending a graft copolymer obtained by graft polymerization on an alkyl acrylate rubber, a graft copolymer obtained by graft polymerization on a conjugated diene rubber, and a hard thermoplastic resin. It is a plastic resin composition, and has characteristics that are extremely excellent in chemical resistance and impact resistance. Therefore, the thermoplastic resin composition of the present invention is extremely useful as a part for home appliances, vehicles, etc., which comes into contact with a urethane foaming agent, various oils, detergents and the like.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C08L 35/00 C08L 35/00 51/00 51/00 51/08 51/08 (56) References JP-A-4-25555 ( JP, A) JP-A-63-278957 (JP, A) JP-A-60-118733 (JP, A) JP-A-59-149915 (JP, A) JP-A-6-228409 (JP, A) Hei 6-240100 (JP, A) JP-A-61-233040 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 51/00-51/08 C08L 25/08-25 / 16 C08L 33/00-33/26 C08L 35/00

Claims (1)

(57) [Claims] (1) The following graft copolymer (A):
(B) one or more graft copolymers (I) selected from the group of (C). (A) 35-85% by weight of alkyl acid alkyl ester
The gel content obtained by emulsion-polymerizing 15 to 65% by weight of a conjugated diene and 0 to 20% by weight of a monomer copolymerizable therewith exceeds 70% by weight, and the average particle size is 0.03 to 0.2%.
μm rubbery copolymer (a) latex, acid group-containing copolymer latex (i) or, if necessary, metal salt of oxygen acid (ii) with acid group-containing copolymer latex (i) The average particle diameter obtained by performing
5 μm enlarged rubbery copolymer (a ′) latex 20
15 to 45% by weight of an unsaturated cyanide compound and 55 to 55% by weight of an aromatic vinyl compound in the presence of
85% by weight of a monomer mixture or 80% to 100% by weight of an alkyl methacrylate and 0% to 20% by weight of an alkyl acrylate
Graft copolymer (A) (B) Conjugated diene rubbery polymer (b) latex
In the presence of 65% by weight (as solid content), a gel content of 70 to 95% by weight of a monomer mixture composed of an alkyl acrylate and a copolymerizable monomer is obtained by seed polymerization. 20 to 80 parts by weight (as solid content) of a composite rubber-like polymer (b ') latex of at least% by weight
Graft copolymer (B) (C) obtained by graft-polymerizing 20 to 80 parts by weight of a monomer mixture comprising 15 to 45% by weight of an unsaturated cyanide compound and 55 to 85% by weight of an aromatic vinyl compound in the presence of ) Polyorganosiloxane rubbery polymer (b-
2) 35 to 95% by weight of a monomer mixture composed of an alkyl acrylate and a monomer copolymerizable therewith is seed-polymerized in the presence of 5 to 65% by weight (as solid content) of latex. Unsaturated cyanide compounds 15 to 4 in the presence of 20 to 80 parts by weight (as solid content) of a composite rubbery polymer (c ') latex having a gel content of 70% by weight or more.
Graft copolymer (C) obtained by graft polymerizing 20 to 80 parts by weight of a monomer mixture comprising 5% by weight and 55 to 85% by weight of an aromatic vinyl compound (II) 70 to 100% by weight of a conjugated diene; An acid group-containing copolymer is added to a conjugated diene rubbery copolymer (d) latex having an average particle size of 0.03 to 0.2 μm obtained by emulsion polymerization of 0 to 30% by weight of a copolymerizable monomer. An enlarged rubbery copolymer (d ') latex obtained by adding a metal salt of an oxygen acid (ii) to the combined latex (i) or the acid group-containing copolymer latex as required,
In the presence of 70 parts by weight (as solid content), 15 to 45% by weight of an unsaturated cyanide compound and 55 to 8% of an aromatic vinyl compound
A graft copolymer (II) obtained by graft polymerization of a monomer mixture consisting of 5% by weight. (III) A hard thermoplastic resin (III) obtained by copolymerizing two or more monomers selected from unsaturated cyanide compounds, aromatic vinyl compounds, unsaturated ester compounds and maleimide compounds. The heat obtained by blending the graft copolymer (I), the graft copolymer (II) and the hard thermoplastic resin (III) with the graft copolymer (I) and the graft copolymer (II) as essential components. A thermoplastic resin composition, wherein the proportion of the rubbery copolymer in 100% by weight of the thermoplastic resin composition is 15 to 30% by weight, and the content of the alkyl acrylate unit forming the rubbery polymer is A thermoplastic resin composition having a ratio of 35 to 85% by weight based on 100% by weight of a rubbery polymer.