JP2000086845A - Resin composition excellent in heat resistance and oil resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition extremely good in the property balance possessing heat resistance and chemical resistance as well while retaining excellent mechanical strength such as impact strength and rigidity by alloying a syndiotactic polystyrene with a PC/HIPS-based composition. SOLUTION: Resin compositions comprise (A) an aromatic polycarbonate resin, (B) a rubber reinforced styrene resin, (C) a copolymer of an aromatic vinyl monomer which contains 2-15 wt.% vinyl cyanider, (D) a polyphenylene ether resin, and (E) a styrenic polymer mainly having syndiotactic structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent heat resistance, impact resistance, rigidity and oil resistance.

[0002]

2. Description of the Related Art Polycarbonate resins are used in various fields such as automobile parts, home electric parts, and OA equipment parts because of their excellent heat resistance and impact resistance. However, one of the drawbacks is that the polycarbonate resin has poor flowability and poor processability.

[0003] Attempts to improve fluidity while maintaining high impact resistance by adding ABS resin (acrylonitrile-butadiene-styrene polymer) or MBS resin (methyl methacrylate-butadiene-styrene polymer) to polycarbonate resin (JP-B-38-15225, JP-B-42-11496). An attempt to improve the fluidity by adding a styrene resin to a polycarbonate resin is proposed in Japanese Patent Publication No. 43-6295. However, the polycarbonate resin and the polystyrene resin have a disadvantage that the impact resistance is reduced due to poor compatibility. German Patent Publication No. 4200247 discloses a resin composition comprising polycarbonate, polyphenylene ether, and styrene-ABS resin. However, the resin composition of this publication has improved heat resistance, but has a disadvantage of poor impact resistance. JP-A-7-324158 describes that a composition comprising a polycarbonate resin, a rubber-reinforced styrene resin, a styrene-vinyl cyanide copolymer, and a polyphenylene ether resin has excellent fluidity and impact resistance. The above composition has excellent fluidity and impact resistance, but chemical resistance,
In particular, it has the disadvantage that its use is limited due to poor oil resistance.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a composition which is excellent in heat resistance, impact resistance and fluidity, but which has greatly improved oil resistance.

[0005]

That is, the present invention provides (A) an aromatic polycarbonate (B) a rubber-reinforced styrene resin (C), an aromatic vinyl monomer containing 2 to 15% by weight of a vinyl cyanide monomer. A resin composition comprising a copolymer resin of a monomer and a vinyl cyanide monomer (D), a polyphenylene ether resin (E), and syndiotactic polystyrene.

The above five components are essential in the resin composition of the present invention, and the object of the present invention is not achieved even if any of the five components is removed. The resin composition excluding the syndiotactic polystyrene which is the component (E) of the present invention has high impact resistance and high fluidity, but has a disadvantage that oil resistance is inferior to PC / ABS resin composition. are doing. The syndiotactic polystyrene as the component (E) in the resin composition of the present invention is a highly crystalline polystyrene having a melting point of 270 ° C. The polymer resin compositions based on the components (A) to (D) described above are all amorphous resins and have essentially no compatibility with crystalline resins. Blends of incompatible resins give only brittle resin compositions with low mechanical strength. However, it has been found that a composition having excellent compatibility, high impact resistance and excellent oil resistance can be obtained only when highly crystalline syndiotactic polystyrene is added to the above four-component amorphous blend resin. The invention has been achieved.

The aromatic polycarbonate of the component (A) used in the present invention may be a phosgene method in which an aromatic dihydric phenolic compound is blown with phosgene in the presence of a caustic alkali and a solvent, or an aromatic dihydric phenolic compound. Examples thereof include those obtained by a transesterification method in which transesterification with diethyl carbonate is carried out in the presence of a catalyst, and may be a homo- or copolymer having a viscosity average molecular weight of 1
Those in the range of 10,000 to 1,000,000 are preferred. The dihydric phenol compound used in the present invention is 2.2'-bis (4-hydroxyphenyl) propane, 2,2'-bis (4-hydroxy-3,5-dimethylfephenyl) propane,
Bis (4-hydroxyphenyl) methane, 2,2′-bis (4-hydroxyphenyl) butane, 2,2′-bis (4-hydroxy-3,5-dipropylphenyl) propane, 1,1′-bis (4-hydroxyphenyl) cyclohexane, 1-phenyl-1,1′-bis (4-hydroxyphenyl) ethane and the like, and 2,2′-bis (4-hydroxyphenyl) propane [bisphenol A] is particularly preferable. Further, dihydric phenols may be used alone or in combination.

In the present invention, the rubber-reinforced styrene resin as the component (B) includes a rubber-like elastic material having rubber-like properties at room temperature, for example, polybutadiene, hydrogenated (or partially hydrogenated) polybutadiene, hydrogenated (or partially hydrogenated). ) Styrene-butadiene block copolymer, polyisoprene, styrene-isoprene copolymer and the like as dispersed particles, styrene monomer,
For example, a resin having a continuous phase of a polymer composed of styrene, α-methylstyrene, p-methylstyrene, pt-butylstyrene, or the like, alone or as a mixture. Known methods for producing these resins include, for example, a solution obtained by dissolving a rubber-like elastic body in a styrene monomer or a polymerization solvent thereof, and adding a catalyst and a chain transfer agent to a raw material solution in which the rubber-like polymer is dissolved. To a reactor equipped with a stirrer,
Polymerization in the temperature range of, after the polymerization, unreacted monomer,
Treatment under vacuum to remove the solvent gives a rubber reinforced styrenic resin.

The component (C) of the present invention plays an important role in determining the physical properties of the composition of the present invention, and the aromatic polycarbonate resin (A) in the composition and the component (A) B) has the function of improving the miscibility of component (D) and component (E). The AN content in the polymer of component (C) is in the range of 2 to 15% by weight, and more preferably 4.0 to 4.0%.
It is in the range of 10.0% by weight. When the AN content is less than 2.0% by weight or exceeds 15.0% by weight, the impact resistance of the composition is significantly reduced. The aromatic vinyl monomer of (C) includes, for example, styrene, α-methylstyrene, p-methylstyrene, pt-butylstyrene, etc., preferably styrene, and the component (C)
Examples of the vinyl cyanide monomer include acrylonitrile and methacrylonitrile, and acrylonitrile is preferable. If necessary, one or more monomers copolymerizable with the aromatic vinyl monomer and the unsaturated nitrile monomer can be introduced as components of the copolymer. The copolymerizable monomer is an acrylate ester having an alkyl group having 1 to 8 carbon atoms such as methyl acrylate and butyl acrylate, and a methacryl having an alkyl group having 1 to 8 carbon atoms such as methyl methacrylate. Acid esters,
Α, β-unsaturated carboxylic anhydrides such as maleic anhydride and itaconic anhydride; and maleimides such as maleimide and N-phenylmaleimide.

[0010] The polyphenylene ether (hereinafter abbreviated as PPE) of the component (D) used in the present invention is a homopolymer and / or a copolymer comprising a bonding unit represented by the following formula.

[0011]

Embedded image

However, R1, R2, R3 and R4 are each selected from the group consisting of hydrogen and substituted hydrocarbon groups, and may be different from each other. Specific examples of the PPE include poly (2,6-dimethyl-1,4-phenylene ether) and a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol. Poly (2,6-dimethyl-1,4-phenylene ether) is preferred. Reduced viscosity of PPE (0.5 g / d
1, chloroform solution, 30 ° C) is 0.2-0.70 d
1 / g, preferably 0.3 to 0.60
More preferably, it is in the range of dl / g. The reduced viscosity of PPE can be adjusted by adjusting the amount of catalyst used in the production. The method for producing PPE can be easily produced, for example, by polymerization using a complex of cuprous salt and an amine as a catalyst according to the method described in US Pat. No. 3,306,874.
No. 061075, U.S. Pat. No. 3,257,357, U.S. Pat. No. 3,257,358, and Japanese Patent Publication No. Sho.
It can be easily produced by the method described in JP-A-2-17880 and JP-A-50-51197.

The styrenic polymer having a syndiotactic structure (hereinafter abbreviated as SPS), which is the component (E) of the present invention, is a crystalline polystyrene-based polymer as compared with ordinary amorphous atactic polystyrene. It has excellent heat resistance and chemical resistance, but is brittle and has poor impact resistance. The syndiotactic polystyrene referred to in the present invention is a polystyrene mainly having a syndiotactic structure. Syndiotactic structure means that the stereochemical structure has a syndiotactic structure, that is, a steric structure in which phenyl groups, which are side chains with respect to a polymer main chain formed from carbon-carbon bonds, are alternately located in opposite directions. The tacticity is determined by nuclear magnetic resonance (13C-NMR) using isotope carbon. Tacticity measured by this method can be represented by the existence ratio of a plurality of continuous structural units, for example, a dyad for two, a triad for three, and a pentad for five. In the present invention, the term "styrenic polymer having a predominantly syndiotactic structure" generally means a syndiotacticity of 75% or more, preferably 85% or more in a dyad, or 30% or more, preferably 50% or more in a pentad. Polystyrene, poly (alkylstyrene), poly (halogenated styrene), poly (alkoxystyrene), poly (vinylbenzoic acid) and mixtures thereof, or copolymers containing these as main components. As poly (alkylstyrene), poly (methylstyrene), poly (ethylstyrene), poly (isopropylstyrene),
Examples include poly (tertiary butyl styrene), and examples of poly (halogenated styrene) include poly (chlorostyrene), poly (bromostyrene), and poly (fluorostyrene). Examples of poly (alkoxystyrene) include poly (methoxystyrene) and poly (ethoxystyrene). Of these, particularly preferred are polystyrene, poly (p-methylstyrene), poly (m-methylstyrene), poly (p-tert-butylstyrene), poly (p-chlorostyrene), and poly (m-styrene).
-Chlorostyrene), poly (p-fluorostyrene), and a copolymer of styrene and p-methylstyrene.

The styrenic polymer used in the present invention is:
Generally, the weight average molecular weight is 5,000 or more, preferably 100
The polymer has a number average molecular weight of 2,500 or more, preferably 5,000 to 1,000,000, and after polymerization, if necessary, is subjected to a demineralization treatment with an acid or alkali washing solution, followed by washing and drying treatment, resulting in extremely syndiotacticity. A large styrenic polymer is obtained. As described above, a styrene-based polymer having a predominantly syndiotactic structure can be obtained, for example, in the presence of a catalyst comprising a titanium compound and an alkylaluminoxane in an inert hydrocarbon solvent or in the absence of a solvent.
And a substituted styrene monomer. As the titanium compound used as the catalyst, there are various compounds, and preferably, a compound represented by the general formula TiR1aR2
bR3cX14- (a + b + c) or TiR1dR2e
X13- (d + e) wherein R1, R2 and R3 are each hydrogen, an alkyl group having 1 to 20 carbon atoms, and 1 to 20 carbon atoms.
Represents an alkoxy group, cyclopentadienyl group, substituted cyclopentadienyl group or indenyl group, and X1 represents a halogen. a, b, and c each represent an integer of 0 to 4, and d and e each represent an integer of 0 to 3. ] At least one compound selected from the group consisting of titanium compounds and titanium chelate compounds. As the above compound, a compound which forms a complex with an ester or an ether may be used. On the other hand, the alkylaluminoxane constituting the main component of the catalyst together with the titanium compound is obtained by contacting various organic aluminum compounds with a condensing agent. As the organoaluminum compound, various compounds can be used, but usually, a trialkylaluminum is used. Trialkyl aluminum includes trimethyl aluminum, triethyl aluminum, tri i
-Butyl aluminum and the like. One or more of these organoaluminum compounds may be used together with the condensing agent. As the condensing agent, water is typically mentioned, but any other agent that causes a condensation reaction of the organoaluminum compound may be used. Further, another organometallic compound may be mixed, or an alkylaluminoxane may be adsorbed or carried on an inorganic substance. The mixing ratio of the above-described titanium compound and alkylaluminoxane varies depending on the type of each component and the raw material styrene, the type of the styrene derivative, and other conditions, and is not uniquely defined. The ratio to titanium in the titanium compound, that is, aluminum / titanium (molar ratio) is 1 to 10 ⁶ , preferably 10 to 10 ⁶ . Further, in the present invention, styrene or a derivative of styrene is polymerized in the presence of the catalyst of the main component, but the polymerization may be in a lump, and an alicyclic hydrocarbon such as cyclohexane or an aliphatic hydrocarbon such as pentane, hexane or heptane, or benzene may be used. May be performed in an aromatic hydrocarbon solvent such as toluene, xylene, or the like. Although the polymerization temperature is not particularly limited, it is usually carried out at 0 to 120 ° C.

The proportion of the component (A) in the composition of the present invention is 25 to 85% by weight, preferably 30 to 80% by weight. The rubber-reinforced styrene resin as the component (B) is 10 to 70% by weight, preferably 20 to 70% by weight.
~ 65% by weight. 2 to 15% by weight of the component (C)
The copolymer of the aromatic vinyl monomer containing the vinyl cyanide monomer and the vinyl cyanide monomer is 2 to 30% by weight, more preferably 3 to 20% by weight. The content of the polyphenylene ether (D) is 2 to 30% by weight, more preferably 3 to 30% by weight. 1 to 80% by weight of syndiotactic polystyrene as the component (E) of the present invention,
More preferably, it is 5 to 50% by weight. If the proportion of the component (A) is less than 25% by weight, impact resistance and rigidity are poor, and if it exceeds 85% by weight, fluidity is poor. If the component (B) is less than 10% by weight, the fluidity is poor, and if it exceeds 70% by weight, the impact resistance is poor. If (C) is less than 2% by weight or more than 30% by weight, the impact resistance is poor. If (D) is less than 2% by weight, the improvement in heat resistance is insufficient, and if it exceeds 30% by weight, the fluidity is poor. If the component (E) is less than 1% by weight, the improvement of oil resistance is insufficient, and if it exceeds 80% by weight, impact resistance is poor.

A thermoplastic elastomer, a styrene-butadiene-based, an ethylene-propylene-based, a polyester-based or a polyurethane-based elastomer can be added to the resin composition of the present invention, if necessary. Particularly, a polystyrene-based thermoplastic elastomer is preferable. The polystyrene elastomer is a block copolymer composed of an aromatic vinyl unit and a conjugated diene unit, or a block copolymer in which the conjugated diene unit is partially hydrogenated.
The conjugated diene monomer constituting the block copolymer,
Examples thereof include 1,3-butadiene and isoprene. In the block structure of the block copolymer, a polymer block composed of an aromatic vinyl unit is represented by S, and a polymer block composed of a conjugated diene and / or a partially hydrogenated unit thereof is represented by B. , SB, S
(SB) Linear of n, where n is an integer of 1-2,
A block copolymer or (SB) nX (where n is 3 to 6)
And X is a star (star) block copolymer represented by silicon tetrachloride, tin tetrachloride, and a coupling residue of a polyepoxy compound) having a B portion as a bonding center. Above all, type 2 of SB, type 3 of SBS, S
BSB type 4 linear block copolymers are preferred.

[0017] The composition of the present invention may optionally contain
One or more light resistance improvers (剤) selected from ultraviolet absorbers, hindered amine light stabilizers, antioxidants, light-blocking agents, metal deactivators and quenchers can be blended. The ultraviolet absorber becomes a keto-type molecule by absorbing light energy and transferring an intramolecular proton (benzophenone, benzotriazole-based), or by cis-trans isomerization (cyanoacrylate-based), It is a component that releases and detoxifies as heat energy. Specific examples are:
2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-
2-hydroxybenzophenones such as octoxybenzophenone, 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone), 2- (2′-hydroxy-5′-methylphenyl) benzotriazole,
2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole, 2- (2'-hydroxy-
3 ', 5'-di-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-t-
Butylphenyl) -5-chlorobenzotriazole, 2
-(2'-hydroxy-3'-t-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-dicumylphenyl) benzotriazole, 2,2' 2- (2 ′) such as -methylenebis (4-t-octyl-6-benzotriazolyl) phenol
-Hydroxyphenyl) benzotriazoles phenyl salicylate, resorcinol monobenzoate, 2,
4-di-t-butylphenyl-3 ′, 5′-di-tert-butyl-4′-hydroxybenzoate, hexadecyl-
Benzoates such as 3,5-di-t-butyl-4-hydroxybenzoate, substituted oxanilides such as 2-ethyl-2′-atoxiogazide, 2-ethoxy-4′-dodecyloxanilide, and ethyl -Α-cyano-
Cyanoacrylates such as β, β-diphenylacrylate and methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate.

The hindered amine light stabilizer is
Decomposes hydroperoxides generated by light energy to produce stable NO radicals, N-OR, N-OH
And a component for stabilizing. Specific examples thereof include 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-
4-piperidyl stearate, 2,2,6,6-tetramethyl-4-piperidyl benzoate, bis (2,2.
6,6-tetramethyl-4-piperazyl sebacate, bis (1,2,2,6,6-pentamethyl-4-piperazyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6
-Pentamethyl-4-piperidyl) -1,2,3,4-
Butanetetracarboxylate, bis (1,2,2,
6,6-pentamethyl-4-piperidyl) di (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperazyl) -2- Butyl-2- (3 ', 5'-di-t-
Butyl-4-hydroxybenzyl) malonate, 1-
(2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4
-Piperidylamino) hexane / 2,4-dichloro-6
-T-octylamino-s-triazine polycondensate, 1,
6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-morpholino-s-triazine polycondensate.

The antioxidant is a component for stabilizing a generated peroxide radical such as a hydroperoxy radical or decomposing a generated peroxide such as a hydroperoxide during heat molding or exposure to light. It is. Specific examples thereof include a hindered phenol-based antioxidant and / or
Or a peroxide decomposer. The former is a radical chain inhibitor, and the latter decomposes the peroxide formed in the system into more stable alcohols to prevent autoxidation. The above-mentioned hindered phenol-based antioxidants include 2,6-dibutyl butyl-4-methylphenol, styrenated phenol, and n-octadecyl 3- (3,5-dibutyl butyl-4-hydroxy). Phenyl) propionate, 2,2-methylenebis (4-methyl-6-tert-butylphenol), 2-tert-butyl-6-
(3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2-
[1- (Hydroxy-3,5-ditacharpentylphenyl) ethyl] -4,6-ditacharpentylphenyl acrylate, 4,4'-butylidenebis (3-methyl-6-tert-butyl) Phenol), alkylated bisphenol, tetrakis [methylene 3-
(3,5-Diterbutyl-4-hydroxyphenyl) propionate] methane, 3,9-bis [2- [3
-(3-tert-butyl-4hydroxy-5-methylphenyl) -propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.
5] Undecane and the like. In addition, the peroxide decomposer,
Organophosphorus peroxide decomposers such as trisnonylphenol phosphite, trisphenyl phosphite, tris (2,4-ditertbutylbutylphenyl) phosphite or dilauryl 3,3′-thiodipropionate, dimyristyl 3,3 ′ -Thiodipropionate, distearyl 3,3'-thiodipropionate, pentaerythrityltetrakis (3-laurylthiopropionate), ditridecyl 3,3'-thiodipropionate, 2-mercaptobenzimidazole And organic sulfur-based peroxide decomposers.

The light shielding agent is a component for preventing light from reaching the bulk of the polymer. Specific examples thereof include rutile titanium oxide (TiO2), zinc oxide (ZnO), chromium oxide (Cr2O3), cerium oxide (CeO2), and the like. The metal deactivator is a component for deactivating heavy metal ions in the resin by a chelate compound. Specific examples include acid amine derivatives, benzotriazoles, and derivatives thereof.

The quenching agent is a component for inactivating functional groups such as photo-excited hydroperoxide and carbonyl group in the polymer by energy transfer, and organic nickel and the like are known. Examples of the apparatus for producing the resin composition of the present invention include an extruder, a Banbury mixer, a normaler, and a kneader. At that time, antioxidants, ultraviolet absorbers, tin-based heat stabilizers, inorganic and halogen-based flame retardants, lubricants such as stearic acid and zinc stearate, fillers, reinforcing agents such as glass fibers, dyes and pigments, etc. Coloring agents can be added as needed. By subjecting the composition of the present invention thus obtained to, for example, injection molding or extrusion molding, a molded article excellent in moldability (fluidity), heat resistance and impact resistance can be obtained.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0023]

EXAMPLES The methods for measuring physical properties and the resins used in the examples and comparative examples will be described. (1) Izod impact strength Measured at 23 ° C. by a method according to ASTM-D256. (V notch, 1/4 inch test piece) (2) Measured by a method based on HDT ASTM-D648. (1/8 inch thickness of test piece, load 18.6kg / cm ² and 4.6kg / cm
² ) (3) Method of measuring falling weight impact strength.

A graphic impact tester type A (Toyo Seiki) was used as a measuring instrument. the detail is right below. Sample test piece: 1/8 inch Injection molded plate Missile diameter: 13Φmm Sample folder diameter: 40mm Missile drop height: 1m (4) Kerosene immersion test.

After the dumbbell pieces were immersed in kerosene at room temperature for 10 days, changes in the surface appearance and the occurrence of cracks were visually determined. No change: ○, small change: Δ, large change or crack occurrence:
× (A) Aromatic polycarbonate Commercially available bisphenol A type polycarbonate (manufactured by Sumitomo Dow Co., Ltd.) Caliber 200-3 was used (hereinafter referred to as PC). (B) Rubber Reinforced Styrene Resin A commercially available rubber reinforced styrene resin (Asahi Kasei polystyrene resin H8117, hereinafter referred to as HIPS) was used. (C) The following styrene-acrylonitrile copolymer was used. (Hereinafter referred to as AS resin) C-1: AS resin containing 6% acrylonitrile A mixed liquid of 74.0% of styrene, 6.0% of acrylonitrile, 20.0% of ethylbenzene, and t-butylperoxyisopropyl carbonate as a polymerization catalyst A mixed solution containing 0.02 parts by weight per 100 parts by weight was added to 1.9.
The reactor was supplied at a rate of 1.2 liter / HR to a complete liter reactor, polymerized at a polymerization temperature of 140 ° C., and the polymerization solution was heated to 220 ° C. (solid content in the polymerization solution was 34% by weight). The mixture was introduced into an extruder, and the unreacted monomer and solvent were separated by evaporation to obtain a polymer. AN in copolymer
% Was 13% by weight (the amount of nitrogen was analyzed by elemental analysis and calculated from the amount of nitrogen). The solution viscosity (25 ° C.) of the polymer dissolved in methyl ethyl ketone was 8.7 cps. C-2: AS resin containing 4.2% by weight of acrylonitrile C-2 was obtained according to the method for producing C-1 described above. C-3: AS resin containing 20% by weight of acrylonitrile Stylac AS resin 8707 (manufactured by Asahi Kasei Kogyo) (D) Polyphenylene ether resin The following polyphenylene ether was used. (Less than
The inside of a stainless steel reactor having an oxygen blowing port at the bottom of the reactor and having a cooling coil and stirring blades inside was sufficiently replaced with nitrogen, and then 54.8 g of cupric bromide and di-n 8.75 kg of 2,6-xylenol was dissolved in a mixed solvent of 1110 g of -butylamine, 20 liters of toluene, 16 liters of n-butanol, and 4 liters of methanol, and charged into the reactor. While stirring, oxygen was continuously blown into the reactor, and polymerization was carried out for 180 minutes while controlling the internal temperature to 30 ° C. After the polymerization was completed, the precipitated polymer was separated by filtration, a mixed solution of methanol / hydrochloric acid was added thereto, the catalyst remaining in the polymer was decomposed, and the polymer was sufficiently washed with methanol and dried.
A powdered polyphenylene ether was obtained. Reduced viscosity ηs
p / C was 0.55 dl / g (chloroform). (E) Syndiotactic polystyrene resin Three grades of XAREC (trade name, manufactured by Idemitsu Petrochemical Co., Ltd.) were used as syndiotactic polystyrene.

[0026]

[Table 1]

Thermoplastic Elastomer Used in Examples and Comparative Examples Fully hydrogenated thermoplastic elastomer (HT) of butadiene portion of styrene / butadiene / styrene block polymer
R) (ToughTech H1081: manufactured by Asahi Kasei Corporation). S (styrene) / EB (ethylene butylene) weight ratio: 6
0/40. Mn: 80,000, Mw / Mn: 1.08.

[0028]

Examples 1 to 8, Comparative Examples 1 to 4 PC,
After blending HIPS, AS, PPE, SPS, and HTR, use a vented twin-screw extruder to obtain a resin temperature of 280 to 300 ° C.
And the mixture was pelletized. The obtained composition was injection molded at a resin temperature of 280 ° C. and a mold temperature of 110 ° C. to prepare a test piece, which was evaluated for physical properties. The results are shown in the table.

In Comparative Example 1 of the present invention, when the acrylonitrile content in the styrene-acrylonitrile copolymer as the component (C) of the present invention is out of the range of the present invention, the impact strength of the composition is significantly reduced. It is shown that. Comparative Examples 2 to 4 show that the effects of the present invention are not achieved even if any of the components (B) to (E) in the composition of the present invention is missing.

Comparative Example 2 shows that the lack of the AS component lowers the Izod impact strength and the falling weight impact strength.
Comparative Example 3 shows that, when syndiotactic polystyrene is omitted, the composition has a high impact strength, but the chemical resistance (particularly oil resistance) and the heat resistance are lower than those of Example 1. I have.

Comparative Example 4 had the drawbacks that the impact resistance was reduced and the composition did not elongate in a tensile test when the polyphenylene ether resin was omitted.

[0032]

[Table 2]

[0033]

[Table 3]

[0034]

According to the present invention, syndiotactic polystyrene is alloyed into a PC / HIPS composition to improve heat resistance and chemical resistance while maintaining excellent mechanical strength such as impact resistance and rigidity. Provided is a resin composition having an extremely excellent balance of physical properties. The resin composition of the present invention can be used as a material for industrial parts in various fields such as automobiles and home appliances, and its industrial value is extremely large.

Claims (1)

[Claims] (A) an aromatic polycarbonate resin,
(B) a rubber-reinforced styrene resin, (C) a copolymer with an aromatic vinyl monomer containing 2 to 15% by weight of a vinyl cyanide monomer, (D) a polyphenylene ether resin, and (E) mainly a A resin composition comprising a styrenic polymer having an tactic structure.