JPH1036626A - Thermoplastic resin composition for blow molding and blow molded item produced therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic resin compsn. which can give a blow molded item excellent in balance between impact resistance and blow moldability and in surface appearance by compounding a specific rubber-reinforced styrene resin and two specific methyl methacrylate copolymers. SOLUTION: This compsn. contains 80-99.8 pts.wt. rubber-reinforced styrene resin contg. 1-50wt.% rubbery polymer having a wt. average particle size of 0.10-0.50μm, 0.1-10 pts.wt. methyl methacrylate copolymer having a methyl methacrylate unit content of 30wt.% or higher and a wt. average mol.wt. of 500,000 or lower, and 0.1-10 pts.wt. methyl methacrylate copolymer having a methyl methacrylate unit content of 30wt.% or higher and a wt. average mol.wt. of 1,000,000 or higher, the sum of the three ingredients being 100 pts.wt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition for blow molding to obtain a blow molded article having an excellent balance between impact resistance and blow moldability and having an excellent surface appearance.

[0002]

2. Description of the Related Art A rubber-reinforced styrene resin represented by an ABS resin has an excellent balance of impact resistance and moldability.
Widely used as resin for injection molding. In recent years, a technique for obtaining a large hollow resin product by blow molding has attracted attention, and a resin composition suitable for blow molding has also been developed for rubber-reinforced styrene-based resins. However, in blow molding, appearance defects may occur due to foreign matters that are considered to be thermal degradation products of the resin due to the stoppage, and it is particularly necessary to pay attention to the stoppage state and stagnation of the resin. Above all, the rubber-reinforced styrene-based resin tends to have a poor surface appearance of the blow-molded product due to the deterioration of the rubber as compared with other polyolefin-based resins.

On the other hand, as a means for improving the surface appearance of a blow-molded product, a method using a blow-molding mold having heating means and cooling means (Japanese Patent Laid-Open No. 7-108534).
However, when such a mold is used, not only is it expensive, but when the parison contains a deteriorated resin composition, the surface appearance is not sufficiently improved. Was.

[0004] The present invention relates to a thermoplastic resin composition for blow molding to obtain a blow-molded product having an excellent balance of impact resistance and blow moldability and excellent surface appearance.

[0005]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies with the aim of solving the above-mentioned problems, and as a result, have found that a rubber-reinforced styrene resin containing a rubbery polymer having a specific particle diameter has a specific property. Blow molding heat is obtained by combining two types of methyl methacrylate copolymers having a composition and a molecular weight at a specific ratio to obtain a blow molded product having an excellent balance of impact resistance, blow molding processability, and excellent surface appearance. The present inventors have found a plastic resin composition and arrived at the present invention.

[0006]

That is, an object of the present invention is to provide a rubber-reinforced styrene resin containing 1 to 50% by weight of a rubbery polymer (a) having a weight average particle diameter of 0.10 to 0.50 μm ( I) 80 to 99.8 parts by weight, 0.1 to 10 parts by weight of a methyl methacrylate-based copolymer (II) having a methyl methacrylate content of 30% by weight or more and a weight average molecular weight of 500,000 or less And the content of methyl methacrylate is 30% by weight or more and the weight average molecular weight is 1
Methyl methacrylate based copolymer (II)
I) It can be achieved by a thermoplastic resin composition for blow molding, comprising 0.1 to 10 parts by weight, the total being 100 parts by weight.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The rubbery polymer (a) used for the rubber-reinforced styrene resin (I) in the present invention is a diene rubber, an acrylic rubber, an ethylene rubber or the like. Polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), polyisoprene, poly (butadiene-butyl acrylate), poly (butadiene-methyl acrylate), poly (butadiene-methyl methacrylate), poly (acrylic acid) Butyl-methyl methacrylate), poly (butadiene-ethyl acrylate), ethylene-propylene rubber,
Examples thereof include ethylene-propylene-diene rubber, poly (ethylene-isobutylene), and poly (ethylene-methyl acrylate). These rubbery polymers are used in one kind or in a mixture of two or more kinds. Among these rubbery polymers, polybutadiene, ethylene-propylene diene rubber and acrylic rubber are particularly preferably used in terms of impact resistance.

The rubber-reinforced styrene resin (I) in the present invention is a styrene resin reinforced with the above rubbery polymer (a), and the presence or absence of grafting of the styrene resin onto the rubbery polymer is limited. However, grafting is more preferable in terms of impact resistance.

The styrene resin is styrene, α
-A polymer or copolymer containing an aromatic vinyl monomer such as methyl styrene, orthomethyl styrene, paramethyl styrene, para-t-butyl styrene and halogenated styrene as a main component. Vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, (meth) ) Unsaturated carboxylic acid alkyl esters such as t-butyl acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, chloromethyl (meth) acrylate and 2-chloroethyl (meth) acrylate (Meth) acrylamide such as methacrylamide and N-methylacrylamide Maleimide monomers such as maleimide, N-methylmaleimide and N-phenylmaleimide; and unsaturated carboxylic anhydride monomers such as maleic anhydride, citraconic anhydride and aconitic anhydride. Among them, acrylonitrile, methyl methacrylate, N-phenylmaleimide and maleic anhydride are particularly preferred in view of blow moldability.

Specifically, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-butadiene-styrene-α-methylstyrene copolymer (MST ABS resin), acrylonitrile-butadiene-styrene-N-phenylmaleimide Copolymer (maleimide-based ABS resin), acrylonitrile-butadiene-styrene-methyl methacrylate copolymer (transparent ABS)
Resin), acrylonitrile-acrylic rubber-styrene copolymer (AAS resin), acrylonitrile-ethylene
Propylene diene rubber-styrene copolymer (AES resin) and the like.

The weight average particle diameter of the rubbery polymer (a) in the rubber-reinforced styrene resin (I) in the present invention needs to be 0.10 to 0.50 μm, particularly 0.15 to 0.50 μm. It is preferably in the range of 40 μm.
Here, if the thickness is less than 0.10 μm or exceeds 0.50 μm, the impact strength of the obtained thermoplastic resin composition for blow molding decreases, which is not preferable. The content of the rubbery polymer (a) in the rubber-reinforced styrene resin (I) is from 1 to 5
It must be 0% by weight. If the content is less than 1% by weight, the resulting thermoplastic resin composition for blow molding has a low impact strength.
If it exceeds 0% by weight, blow molding processability is poor, which is not preferable. Among them, 5-45% by weight is preferable.

The reduced viscosity of the acetone-extracted component of the rubber-reinforced styrenic resin (I) in the present invention is from 0.3 to 1.0 dl / b in terms of the blow molding processability of the obtained thermoplastic resin composition for blow molding. g is preferred. Above all,
0.4 to 0.9 dl / g is more preferred.

The graft ratio of the rubber-reinforced styrene resin (I) is not particularly limited, but is preferably 5 to 100% by weight. The reduced viscosity of the copolymer of the graft component is not particularly limited, but is preferably 0.2 to 1.0 dl / g from the viewpoint of impact resistance.

In the present invention, the methyl methacrylate-based copolymer (II) and the methyl methacrylate-based copolymer (II)
I) is a copolymer of methyl methacrylate and another vinyl monomer copolymerizable with methyl methacrylate. Specifically, copolymers of unsaturated carboxylic acid esters except methyl methacrylate and methyl methacrylate Polymers are exemplified, and among them, n-butyl acrylate / methyl methacrylate copolymer is preferably used.

In the present invention, the methyl methacrylate copolymer (II) and the methyl methacrylate copolymer (II)
In (I), the content of methyl methacrylate needs to be 30% by weight or more. If the amount is less than 30% by weight, the blow molding processability of the obtained thermoplastic resin composition for blow molding is not preferable.

Further, a methyl methacrylate-based copolymer (I
In (I), the weight average molecular weight needs to be 500,000 or less. If it exceeds 500,000, the resulting thermoplastic resin composition for blow molding is inferior in appearance, which is not preferable. Among them, those having a weight average molecular weight of 300,000 or less are particularly preferable.

Also, methyl methacrylate copolymer (II
In (I), the weight average molecular weight needs to be 1,000,000 or more. If the amount is less than 1,000,000, the blow molding processability of the obtained thermoplastic resin composition for blow molding is not preferable.
Among them, those having a weight average molecular weight of 1.5 million or more are particularly preferable.

In the thermoplastic resin composition for blow molding of the present invention, the compounding ratio of the rubber-reinforced styrene resin (I), methyl methacrylate copolymer (II) and methyl methacrylate copolymer (III) is as follows: 80 to 99.8 parts by weight of a rubber-reinforced styrene resin (I), 0.1 to 10 parts by weight of a methyl methacrylate copolymer (II) and 0.1 to 10 parts by weight of a methyl methacrylate copolymer (III) Parts by weight,
The total must be 100 parts by weight. If the rubber-reinforced styrenic resin (I) is less than 80 parts by weight, the resulting thermoplastic resin composition for blow molding has insufficient impact strength.
If the amount exceeds 99.8 parts by weight, the blow molding processability is inferior, which is not preferable. If the amount of the methyl methacrylate-based copolymer (II) is less than 0.1 part by weight, the surface appearance of the obtained blow-molded article is poor, and if it exceeds 10 parts by weight, the blow-molding processability is inferior. If the amount of the methyl methacrylate-based copolymer (III) is less than 0.1 part by weight, the blow molding processability of the obtained thermoplastic resin composition for blow molding is poor. The impact strength of the resulting thermoplastic resin composition for blow molding is not preferred.

The effect of the methyl methacrylate copolymer (II) in the present invention is not well understood, but by adding the methyl methacrylate copolymer (II),
It is presumed that the resin hardly adheres to the screw and the like in the blow molding machine, so that the resin does not easily stay, there is little foreign matter due to thermal deterioration, and the surface appearance of the blow molded product is improved.

In the present invention, vinyl chloride, polyethylene, and the like are used as long as the effects of the present invention are not impaired.
Polyolefin such as polypropylene, polyamide such as nylon 6, nylon 66 and nylon 46, polyester such as polyethylene terephthalate, polybutylene terephthalate, polycyclohexanedimethyl terephthalate and polyethylene naphthalate, polycarbonate, polyphenylene sulfide, polyphenylene ether, and various thermoplastic elastomers are added. can do.

In the present invention, if necessary, 2,6-di-tert-butyl-4-methylphenol, 4,
Phenolic antioxidants such as 4'-butylidene-bis (3-methyl-6-t-butylphenol); phosphorus-based oxidations such as tris (mixed, mono- and dinonylphenyl) phosphites and diphenyl isodecyl phosphite Antioxidants, sulfur-based antioxidants such as dilauryl thiodipropionate, dimyristyl thiodipropionate diasterial thiodipropionate, 2-hydroxy-4
-Octoxybenzophenone, 2- (2-hydroxy-
UV absorbers such as 5-methylphenyl) benzotriazole, bis (2,2,6,6, -tetramethyl-4-
Light stabilizers such as piperidinyl), antistatic agents such as hydroxylalkylamine and sulfonate, lubricants such as ethylenebisstearylamide and metal soap, glass fibers,
Inorganic filler such as carbon fiber, tetrabromobisphenol A, decabromodiphenyl oxide, TBA
It is also possible to add a flame retardant such as an epoxy oligomer, a TBA polycarbonate oligomer, antimony trioxide, a coloring agent, and the like.

Hereinafter, an example of a method for producing the thermoplastic resin composition for blow molding of the present invention will be described. The method for producing the rubber-reinforced styrenic resin (I) in the present invention is not particularly limited, and may be an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method,
It can be produced by a conventionally known polymerization method using a solution polymerization method or a combination thereof.

The method for producing the methyl methacrylate-based copolymers (II) and (III) in the present invention is not particularly limited, and includes emulsion polymerization, suspension polymerization, bulk polymerization, solution polymerization, and the like. Can be produced by a conventionally known polymerization method by a combination of the above. Among them, the emulsion polymerization method is particularly preferable.

The thermoplastic resin composition for blow molding of the present invention relates to the blending and melting of a rubber-reinforced styrene resin (I), a methyl methacrylate copolymer (II) and a methyl methacrylate copolymer (III). Extrusion is not particularly limited, and a generally known method can be employed. Rubber-reinforced styrene resin (I), methyl methacrylate copolymer (II) and methyl methacrylate copolymer (II)
In the case of the compounding of I), for example, a ribbon blender, a V-type blender, a Henschel mixer or the like can be used. A kneading process using an extruder such as a single-screw extruder or a twin-screw extruder, a Banbury mixer, a mixing roll, a pressure kneader, or the like can be employed.

[0025]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples, but these Examples do not limit the present invention. Reference Examples, Examples,
Parts and% in the comparative examples represent parts by weight and% by weight, respectively. The physical properties of the obtained rubber-reinforced styrene resin (I), methyl methacrylate copolymer (II), methyl methacrylate copolymer (III) and thermoplastic resin composition for blow molding are as follows: It was determined by the following test method.

Weight average particle size: sodium alginate method.

Graft ratio: Acetone was added to the rubber-reinforced styrene resin (I) (weight M), and the mixture was refluxed for 3 hours. After centrifuging the solution for 40 minutes, the insoluble matter was filtered and the insoluble matter was removed at 60 ° C. for 5 minutes. After drying under reduced pressure for a time, the weight (N) was measured. The graft ratio was determined by the following equation. Here, L in the formula is the rubber content (%) in the rubber-reinforced styrene resin. Graft rate (%) = 100 × (N−M × L / 100) /
(M × L / 100)

Reduced viscosity (ηsp / c): The rubber-reinforced styrene resin (I) is obtained by performing the same operation as in the above-mentioned measurement of the graft ratio, and drying acetone-soluble components under reduced pressure at 60 ° C. for 5 hours. The acetone-soluble component of the rubber-reinforced styrene-based resin (I) thus obtained was adjusted to an acetone solution having a sample concentration of 0.4 g / dl, and measured at a measurement temperature of 30 ° C. using an Ubbelohde viscometer. .

Weight average molecular weight: Using a gel permeation chromatograph GPC-244 manufactured by WATERS, the weight average molecular weight was determined based on polystyrene under the following measurement conditions. Column TSK-gel-GMH _XL , solvent tetrahydrofuran, flow rate 1.0 ml / min, 23 ° C., sample concentration 0.1
%, Differential refractive index detector.

1/2 inch, notched Izod impact strength: Measured according to ASTM D256 for an injection molded product of a thermoplastic resin composition for blow molding. The Izod impact strength of the present invention as a passing level is 20 kg.
cm / cm or more.

Blow molding workability: １．５ indicates that a 1.5 m parison did not draw down for 30 seconds or more, and ○ indicates that it did not draw down for 15 seconds or more. Also,
A sample having a severe drawdown or a sample in which melt fracture was caused and a parison having a uniform thickness was not obtained was determined as x.

Surface appearance of blow-molded articles: 0 to 3 foreign substances (unusual or protrusions) per 1000 cm ^{2 of} blow-molded article surface ○, 4 to 10 foreign substances △, 11 The above was evaluated as x.

Reference Example 1 Rubber-reinforced styrene resin (I)
Production of A In a reactor purged with nitrogen, 120 parts of pure water and 0.5 part of glucose
Part, sodium pyrophosphate 0.5 part, ferrous sulfate 0.0
05 parts and 60 parts (in terms of solid content) of polybutadiene latex having a rubber weight average particle diameter of 0.35 μm were charged, and the temperature in the reactor was raised to 65 ° C. while stirring.
When the internal temperature reaches 65 ° C., the polymerization is started and styrene 3
A mixture consisting of 0 parts, 10 parts of acrylonitrile and 0.3 parts of t-dodecylmercaptan was continuously added dropwise over 5 hours. At the same time, 0.25 parts of cumene hydroperoxide, 2.5 parts of potassium oleate and 2 parts of pure water
An aqueous solution consisting of 5 parts was continuously added dropwise over 7 hours to complete the reaction. The obtained rubber-containing graft copolymer latex was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to obtain a rubber-containing graft copolymer.

In a stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a Fowler-type stirring blade, a methyl methacrylate / acrylamide copolymer (Japanese Patent Publication No.
A solution obtained by dissolving 0.05 part in 165 parts of ion-exchanged water was stirred at 400 rpm, and the inside of the system was replaced with nitrogen gas. Then 28 parts of acrylonitrile,
Styrene 72 parts, t-dodecyl mercaptan 0.3 parts,
A mixed solution of 0.40 parts of 2,2′-azobisisobutyronitrile was added while stirring the reaction system, and the temperature was raised to 60 ° C. to initiate polymerization. After raising the reaction temperature to 65 ° C over 15 minutes, the temperature was raised to 100 ° C over 50 minutes. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to a usual method to obtain a styrene-acrylonitrile copolymer. 70 parts by weight of this styrene-acrylonitrile copolymer and 0.3 parts of 2,6-di-t-butyl-4-methylphenol were added to 30 parts by weight of the rubber-containing graft copolymer, and diphenyl isodecyl phosphite was used. Was melt-mixed using a 40 mm single screw extruder to obtain a rubber-reinforced styrene resin (I) A. Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) A.

Reference Example 2 Rubber-reinforced styrene resin (I)
Production of B In the same manner as in Reference Example 1, a rubber-containing graft copolymer was obtained. Next, in a stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a Fowler-type stirring blade, 150 parts of ion-exchanged water, 0.5 part of sodium dodecyl sulfate,
D-glucose 0.5 part, sodium pyrophosphate 0.4
And 0.005 part of ferrous sulfate, charged with nitrogen gas, and heated to 70 ° C. while stirring. Next, a mixture consisting of 78 parts of α-methylstyrene, 22 parts of acrylonitrile, 0.1 part of t-dodecyl mercaptan, 0.25 part of cumene hydroperoxide, and 2.0 parts of sodium dodecyl sulfate was added at a constant speed over 8 hours. Thereafter, the temperature was raised to 90 ° C. to complete the polymerization.

Thereafter, the reaction system is cooled, and the polymer is coagulated with magnesium chloride, separated, washed and dried to obtain α-
A methylstyrene-acrylonitrile copolymer was obtained.

For 30 parts by weight of the rubber-containing graft copolymer, 70 parts by weight of the α-methylstyrene-acrylonitrile copolymer and 2,6-di-t-butyl-4
-0.3 part of methylphenol and 0.1 part of diphenyl / isodecyl phosphite are blended and melt-mixed using a 40 mm single screw extruder to obtain a rubber-reinforced styrene resin (I) B
Was obtained. The composition of this rubber-reinforced styrene resin (I) B,
Table 1 shows the graft ratio and the reduced viscosity of the acetone extraction component.
It was shown to.

Reference Example 3 Rubber-reinforced styrene resin (I)
Production of C In the same manner as in Reference Example 1, a rubber-containing graft copolymer was obtained. Styrene-acrylonitrile-N manufactured by Nippon Shokubai Co., Ltd. was added to 40 parts by weight of the rubber-containing graft copolymer.
-Phenylmaleimide copolymer (PAS1430) 30
Parts by weight, 30 parts by weight of the styrene-acrylonitrile copolymer obtained in Reference Example 1, 0.3 part of 2,6-di-t-butyl-4-methylphenol and 0.1 part of diphenyl isodecyl phosphite The resulting mixture was melt-mixed using a 40 mm single screw extruder to obtain a rubber-reinforced styrene resin (I) C. Table 1 shows the composition, graft ratio, and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) C.

Reference Example 4 Rubber-reinforced styrene resin (I)
Production of D In the same manner as in Reference Example 1, a rubber-containing graft copolymer was obtained. Next, a methyl methacrylate / acrylamide copolymer (JP-B-45) was placed in a stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a Fowler-type stirring blade.
-24151) 0.05 parts of ion-exchanged water 1
The solution dissolved in 65 parts was stirred at 400 rpm, and the inside of the system was replaced with nitrogen gas. Next, a mixed solution of 4 parts of acrylonitrile, 24 parts of styrene, 72 parts of methyl methacrylate, 0.3 part of t-dodecylmercaptan, and 0.40 part of 2,2′-azobisisobutyronitrile was stirred while stirring the reaction system. The mixture was added and the temperature was raised to 60 ° C. to initiate polymerization. After raising the reaction temperature to 65 ° C. in 15 minutes, 10 minutes in 50 minutes
The temperature was raised to 0 ° C. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to a usual method to obtain a styrene-acrylonitrile-methyl methacrylate copolymer. For 30 parts by weight of the rubber-containing graft copolymer, 70 parts by weight of the styrene-acrylonitrile-methyl methacrylate copolymer and 0.3 part of 2,6-di-t-butyl-4-methylphenol, Isodecyl phosphite was blended and melt-mixed using a 40 mm screw extruder to obtain a rubber-reinforced styrene resin (I) D. Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) D.

Reference Example 5 Rubber-reinforced styrene resin (I)
E A stainless steel autoclave equipped with a baffle and a Fowler-type stirring blade was charged with 248 parts of ion-exchanged water and 0.1 part of sodium dihexylsulfosuccinate, and was replaced with nitrogen gas while stirring, and then heated to 75 ° C.
Next, after adding 0.15 part of ammonium persulfate, 80 parts of methyl methacrylate and n-butyl acrylate 2 were added.
A mixture of 0 parts was added continuously over 50 minutes. After the addition, 0.1 part of ammonium persulfate was further added, and the reaction was continued at 75 ° C. for 45 minutes.
An acrylic rubber latex was obtained. 300 parts of styrene, 100 parts of acrylonitrile, 0.3 part of t-dodecyl mercaptan and 0.3 part of ammonium persulfate were added to this latex.
The mixture of 3 parts was added continuously over 70 minutes. Thereafter, the reaction system is cooled, the polymer is separated, washed, and dried according to a usual method, and acrylonitrile-
A rubber-reinforced styrene resin (I) E, which is an acrylic rubber-styrene copolymer (AAS resin), was obtained. Table 1 shows the composition, graft ratio, and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) E.

Reference Example 6 Rubber-reinforced styrene resin (I)
F In a stainless steel autoclave equipped with a baffle and a Faudra type stirring blade, 40 parts of ethylene-propylene-diene rubber (iodine value 24, Mooney clay 65, ethylene / propylene = 77.6 / 22.4 molar ratio) and n- After putting and dissolving 150 parts of heptane and 250 parts of isopropylbenzene, 35 parts of styrene, 25 parts of acrylonitrile and 1 part of benzoyl peroxide were added,
Mix evenly. Next, 700 parts of ion-exchanged water and 3 parts of a 25% aqueous solution of polyacrylic acid were added, the gas phase was replaced with nitrogen gas, and polymerization was performed at 80 ° C. for 7 hours. The obtained slurry was filtered and dried to obtain a rubber-reinforced styrene resin (I) F which is an AES resin. Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) F.

Reference Example 7 Rubber-reinforced styrene resin (I)
Production of G In Reference Example 1, a polybutadiene latex 6 having a weight average particle diameter of 0.05 μm was prepared.
A rubber-reinforced styrene resin (I) G was obtained in the same manner as in Reference Example 1 except that the amount was changed to 0 part (in terms of solid content). Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) G.

Reference Example 8 Rubber-reinforced styrene resin (I)
Production of H In reference example 1, polybutadiene latex 5 having a weight average particle diameter of 0.60 μm was used.
A rubber-reinforced styrene-based resin (I) H was obtained in the same manner as in Reference Example 1 except that the amount was changed to 0 parts (in terms of solid content). Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) H.

Reference Example 9 Rubber-reinforced styrene resin (I) I
Production of Reference Example 1 was carried out in the same manner as in Reference Example 1, except that 30 parts by weight of the rubber-containing graft copolymer was changed to 90 parts by weight, and 70 parts by weight of the styrene-acrylonitrile copolymer was changed to 10 parts by weight. A rubber-reinforced styrene resin (I) I was obtained. Table 1 shows the composition, graft ratio and reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) I.

Reference Example 10 Production of methyl methacrylate copolymer (II) a 250 parts of pure water was placed in a reaction vessel equipped with a stirrer and a reflux condenser.
1.5 parts of dioctyl sulfosuccinate soda salt,
0.2 parts of ammonium persulfate, methyl methacrylate 85
Parts, 15 parts of n-butyl acrylate and 0.50 part of n-octylmercaptan, and the inside of the vessel was purged with nitrogen. Then, the temperature of the reaction vessel was raised to 55 ° C., and the mixture was heated and stirred for 6 hours. After cooling, the mixture was coagulated with aluminum chloride to obtain a methyl methacrylate-based copolymer (II) a shown in Table 2.

Reference Example 11 Production of methyl methacrylate-based copolymer (II) b Same as Reference Example 10 except that 0.50 part of n-octyl mercaptan was changed to 0.30 part in the conditions of Reference Example 10. To obtain a methyl methacrylate-based copolymer (II) b shown in Table 2.

REFERENCE EXAMPLE 12 Production of methyl methacrylate copolymer (II) c Reference example 10 was the same as reference example 10, except that methyl methacrylate was 25 parts and n-butyl acrylate was 75 parts. In the same manner as in Example 10, a methyl methacrylate-based copolymer (II) c shown in Table 2 was obtained.

Reference Example 13 Production of methyl methacrylate-based copolymer (III) In the same manner as in Reference Example 10, except that 0.50 part of n-octyl mercaptan was changed to 0.05 part from the conditions of Reference Example 10. As a result, a methyl methacrylate copolymer (III) shown in Table 2 was obtained.

Reference Example 14 Production of methyl methacrylate copolymer (III) The procedure of Reference Example 10 was repeated except that the conditions of Reference Example 10 were changed to 0.05 parts of n-octyl mercaptan and 0.2 parts. As a result, a methyl methacrylate copolymer (III) shown in Table 2 was obtained.

Reference Example 15 Production of methyl methacrylate copolymer (III) Reference Example 10 was repeated except that the conditions of Reference Example 10 were changed to 25 parts of methyl methacrylate and 75 parts of n-butyl acrylate. In the same manner as described above, a methyl methacrylate-based copolymer (III) shown in Table 2 was obtained.

Examples 1 to 6 Production of thermoplastic resin compositions for blow molding Rubber-reinforced styrene resins (I) A to F produced in Reference Examples 1 to 6, methacrylic acid produced in Reference Example 10 After the methyl copolymer (II) a and the methyl methacrylate copolymer (III) produced in Reference Example 13 were kneaded with a Henschel mixer at a mixing ratio shown in Table 3, 40 m
A thermoplastic resin composition for blow molding was obtained by extrusion with an mφ extruder. A test piece was prepared from the obtained thermoplastic resin composition for blow molding by injection molding, and the Izod impact strength was measured. The measured value is shown in Table 3. Table 3 shows the results of the blow molding processability and the surface appearance of the molded product.

Comparative Examples 1 to 7 Production of thermoplastic resin compositions for blow molding Rubber-reinforced styrene resins (I) A to I produced in Reference Examples 1 to 9 and produced in Reference Examples 10 to 12 Methyl methacrylate-based copolymers (II) ac and Reference Examples 13 to
Methyl methacrylate copolymer (II)
After kneading (I) to (5) in the mixing ratio shown in Table 3, the mixture was extruded with a 40 mmφ extruder to obtain a thermoplastic resin composition for blow molding. A test piece was prepared from the obtained thermoplastic resin composition for blow molding by injection molding, and the Izod impact strength was measured. The measured value is shown in Table 4.
Table 3 shows the results of the blow molding processability and the surface appearance of the molded product.

From Examples 1 to 6, it can be seen that the thermoplastic resin composition for blow molding according to the present invention has an excellent balance of impact resistance and blow moldability, and also has excellent surface appearance. . However, in Comparative Examples 1 to 3, rubber-reinforced styrene resin (I) and methyl methacrylate copolymer (II)
Comparative Example 1 had a low impact strength, Comparative Example 2 had poor surface appearance, and Comparative Example 3 had a compounding ratio of methyl methacrylate-based copolymer (III) outside the range specified in the present invention.
Is inferior in blow molding processability. In Comparative Examples 4 to 9, rubber-reinforced styrene resin (I), methyl methacrylate copolymer (II) and methyl methacrylate copolymer (II) were used.
Since I) is out of the range specified in the present invention, Comparative Example 4 is inferior in impact strength, blow moldability and surface appearance,
Comparative Example 5 is inferior in impact strength and blow moldability, Comparative Example 6 is inferior in blow moldability and surface appearance, and Comparative Example 7 is inferior in blow moldability. Thus, from each of Examples and Comparative Examples, the thermoplastic resin composition for blow molding of the present invention is excellent in impact resistance, blow molding workability, and surface appearance balance. This is realized for the first time by combining two types of methyl methacrylate-based copolymers having a specific composition and molecular weight in a specific ratio with a rubber-reinforced styrene-based resin containing a rubbery polymer having a specific particle size. Things.

[0054]

[Table 1]

[Table 2]

[Table 3]

[0055]

The thermoplastic resin composition for blow molding according to the present invention is a rubber-reinforced styrene-based resin containing a rubbery polymer having a specific particle size and having a specific composition and a specific molecular weight.
By combining various types of methyl methacrylate-based copolymers at a specific ratio, excellent balance of impact resistance, blow moldability and surface appearance is obtained.

The thermoplastic resin composition for blow molding of the present invention can be used for blow molding by utilizing these characteristics. However, the large hollow resin parts for automobiles and motorcycles and the large hollow resin parts for houses are used. It is suitable as a resin material for large hollow resin parts for electric equipment.

Continued on the front page (51) Int.Cl. ⁶ Identification number Reference number in the agency FI Technical display location C08L 33:12)

Claims (11)

[Claims] (1) a weight average particle diameter of 0.10 to 0.50 μm;
80 to 99.8 parts by weight of a rubber-reinforced styrene-based resin (I) containing 1 to 50% by weight of a rubbery polymer (a), having a methyl methacrylate content of 30% by weight or more and a weight average molecular weight of 0.1 to 10 parts by weight of methyl methacrylate copolymer (II) having a molecular weight of 500,000 or less and methyl methacrylate having a methyl methacrylate content of 30% by weight or more and a weight average molecular weight of 1,000,000 or more Copolymer (III) consisting of 0.1 to 10 parts by weight, the total being 1
A thermoplastic resin composition for blow molding, wherein the amount is 00 parts by weight. 2. The rubber-reinforced styrene resin (I) is an acrylonitrile-butadiene-styrene copolymer (ABS)
The thermoplastic resin composition for blow molding according to claim 1, which is a resin. 3. The method according to claim 1, wherein the rubber-reinforced styrene resin (I) is an acrylonitrile-butadiene-styrene-α-methylstyrene copolymer (MST ABS resin). Thermoplastic resin composition for blow molding. 4. The rubber-reinforced styrene resin (I) is an acrylonitrile-butadiene-styrene-N-phenylmaleimide copolymer (maleimide ABS resin). Thermoplastic resin composition for blow molding. 5. The blow according to claim 1, wherein the rubber-reinforced styrene resin (I) is an acrylonitrile-butadiene-styrene-methyl methacrylate copolymer (transparent ABS resin). Thermoplastic resin composition for molding. 6. The rubber-reinforced styrene resin (I) is an acrylonitrile-acryl rubber-styrene copolymer (AA)
The thermoplastic resin composition for blow molding according to any one of claims 1 to 5, wherein the thermoplastic resin composition is an S resin. 7. The blow molding according to claim 1, wherein the rubber-reinforced styrene resin (I) is an acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin). Thermoplastic resin composition. 8. The blow molding according to claim 1, wherein the reduced viscosity of the acetone-extracted component of the rubber-reinforced styrene resin (I) is 0.3 to 1.0 dl / g. Thermoplastic resin composition. 9. The methyl methacrylate copolymer (II)
Is a methyl methacrylate / n-butyl acrylate copolymer. The thermoplastic resin composition for blow molding according to any one of claims 1 to 8. 10. The methyl methacrylate copolymer (II)
The thermoplastic resin composition for blow molding according to any one of claims 1 to 9, wherein I) is a methyl methacrylate / n-butyl acrylate copolymer. 11. A blow-molded article comprising the thermoplastic resin composition for blow molding according to claim 1.