JP3355245B2 - Transparent high-impact resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent and high impact resistance resin composition having a good balance of surface impact resistance and transparency. A resin composition suitable for a transparent molded article that requires a high degree of transparency and surface impact resistance, such as a container obtained by performing bending molding, press molding, a container or a container obtained by injection molding or a profile extrusion molding. About.

[0002]

2. Description of the Related Art A block copolymer resin comprising a vinyl aromatic hydrocarbon and a conjugated diene is a resin having excellent transparency and impact resistance, and is widely used for sheets, films, injection molded products and the like. . However, there is a trade-off relationship that the resin having excellent impact resistance has low rigidity, whereas the resin having high rigidity has low impact resistance, and in particular, both the surface impact resistance and the rigidity are excellent. In fact, block copolymer resins have not yet been obtained.

An attempt to improve the Izod impact strength as impact resistance is disclosed in Japanese Patent Publication No. 52-16496. When rubber-modified polystyrene is added to the styrene / butadiene block copolymer in an amount of 15% or more, the impact strength is improved, but the transparency is significantly reduced. When the rubber-modified polystyrene content is 0.5%, the impact resistance, strength and rigidity are the same as when rubber-modified polystyrene is not blended, and no improvement effect is observed. JP-B-59-258
No. 21 discloses a polymer composition comprising a rubber-modified impact-modified styrene polymer modified with a block copolymer having a specific structure, and a block copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene, It is described as having excellent impact resistance and transparency. However, the disclosed rubber-modified impact-resistant styrene polymer has its own Izod impact strength lower than that of the conventional one, and does not reach sufficient impact resistance. JP-A-51-89550 discloses a transparent impact-resistant styrene polymer composition comprising a block copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene, a rubber-modified styrene polymer and a styrene polymer. ing. However, even in this composition, there is no composition which can satisfy both transparency and impact resistance.

[0004] In recent years, from the viewpoint of protection of the global environment, the trend of replacing chlorine-based resins with non-chlorine-based resins has become active, and resins having an excellent overall balance of rigidity, transparency and impact resistance have been developed. Is desired. JP-A-4-3935
No. 1 discloses a styrene resin (a styrene homopolymer or a copolymer with acrylonitrile) and a compound of the general formula A1 -BA
2 discloses a resin composition with the block copolymer. However, the block copolymer resin composition shown here does not have sufficient impact resistance at a low temperature of the block copolymer itself, and the impact resistance is significantly reduced at a temperature of 0 ° C. or lower, so that the resin composition is stored in a refrigerator or the like. However, there is a disadvantage that the use as a food packaging container or the use in cold regions is restricted. JP-A-4-57845 discloses a composition of a styrene-based copolymer resin and a block copolymer. Although the block copolymer shown here is composed of a block mainly composed of a styrene component and a block copolymer mainly composed of a conjugated diene, the ratio of the components constituting each block is clearly shown. In the examples, each block is a styrene / butadiene homopolymer block. Therefore, when using a block copolymer having a high content of vinyl aromatic hydrocarbons among the block copolymers as in the examples, the impact resistance is insufficient, and conversely, the content of the vinyl aromatic hydrocarbons is low. When a small amount of the block copolymer is used, not only the rigidity is remarkably reduced, but also the molded product has a disadvantage that the molded product looks pale. JP-A-4-236
JP-A-239-239 discloses a styrene-based resin sheet comprising a styrene-based copolymer resin and a block copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene.
No. 56 discloses a styrene-based polymer, a rubber-reinforced styrene-based polymer, and a transparent styrene-based resin comprising a block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene, and describes that the resin has excellent strength and transparency. Have been. However, this sheet and the transparent styrene resin are not yet sufficiently satisfactory in both the surface impact resistance and the rigidity.
Since the sheet surface is not smooth, there is a problem of lack of clear feeling.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an extruded sheet which requires a high degree of transparency, rigidity and surface impact resistance.
Highly transparent, especially transparent and sheet-free, surface of molded products, especially for films, vacuum-formed, press-formed, bent-formed containers, cases or containers obtained by injection molding, profile extrusion molding, especially defects that appear pale Smoothness,
An object of the present invention is to provide a resin composition which is excellent in balance between rigidity, room temperature and surface impact resistance of -10 ° C or less.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to improve the bluishness of the sheet, the smoothness of the sheet surface, and the rigidity and surface impact resistance of the sheet all at once. And a rubber-modified impact-resistant polystyrene and / or vinyl resin having a specific structure comprising a thermoplastic block copolymer having a specific structure consisting of styrene and a conjugated diene, and a copolymer resin of a vinyl aromatic hydrocarbon and a (meth) acrylate. The resin composition to which the block copolymer elastomer of the aromatic hydrocarbon and the conjugated diene is added and blended has no paleness, is excellent in the smoothness of the sheet surface, and has high rigidity. The present inventors have found that they have a performance having a high level of surface impact resistance of 10 ° C. or less, and have completed the present invention.

That is, according to the present invention, the following component (a) comprises 10
A transparent high-resistance composition comprising component (c) and / or component (d) in a composition comprising at least 90 parts by weight of component (b) and at least 90 parts by weight of component (b). An impact resin composition, (a) at least two vinyl aromatic hydrocarbon-based polymer blocks A and at least one
A block copolymer comprising a polymer block B mainly composed of two conjugated dienes, wherein the content of the vinyl aromatic hydrocarbon in the block copolymer is 65% by weight or more and 80% by weight or less. The block ratio of the vinyl aromatic hydrocarbon polymer block incorporated in the polymer is 50% by weight or more and 80% by weight or less, and is a value obtained by reducing the weight average molecular weight of the vinyl aromatic hydrocarbon polymer block by the number average molecular weight.
The molecular weight distribution exceeds 1.6 and the molecular weight distribution is
(B) a vinyl aromatic hydrocarbon having a (meth) acrylic ester content of 8% by weight or more and 25% by weight or less of a block copolymer having 0000 or more components of 15% by weight or more and 60% by weight or less; (Meth) acrylic ester copolymer resin, (c) rubber-modified impact-resistant polystyrene obtained by graft-polymerizing styrene to a butadiene rubber-like polymer, (d) vinyl aromatic hydrocarbon content is 10% by weight or more. , A block copolymer elastomer of 50% by weight or less of a vinyl aromatic hydrocarbon and a conjugated diene.

Hereinafter, the present invention will be described in detail. The block copolymer used in the present invention has a polymer structure of A-
(BA) _n , B- (AB) _n -A, B- (AB)
_{n + 1} (In the above formula, A is a polymer block mainly composed of a vinyl aromatic hydrocarbon, and B is a polymer block mainly composed of a conjugated diene. The boundary between the A block and the B block is not necessarily clear. Need not be distinguished from each other.
A linear block copolymer represented by the above integer, generally 1 to 5) or a general formula: [(AB) _k ]
_{m + 2-} X, [(AB) _k- A] _{m + 2-} X, [(B-
A) _k ] _{m + 2} −X, [(BA) _k −B] _{m + 2} −X
(In the above formula, A and B are the same as described above, and k and m
Is an integer of 1 or more, generally 1 to 5. X represents a residue of a coupling agent such as silicon tetrachloride, tin tetrachloride, 1,3 bis (N, N-glycidylaminomethyl) cyclohexane or a residue of an initiator such as a polyfunctional organic lithium compound. )) Or a mixture of these block copolymers having an arbitrary polymer structure.

Here, the polymer block mainly composed of vinyl aromatic hydrocarbon is defined as having a vinyl aromatic hydrocarbon content of 50.
A copolymer block of a vinyl aromatic hydrocarbon and a conjugated diene and / or a homopolymer block of a vinyl aromatic hydrocarbon containing not less than 50% by weight, wherein the polymer block mainly composed of a conjugated diene is 50% by weight of a conjugated diene. % Shows a conjugated diene and vinyl aromatic hydrocarbon copolymer block and / or a conjugated diene homopolymer block contained in an amount exceeding%.

When a random copolymer portion of a vinyl aromatic hydrocarbon and a conjugated diene is present in a polymer block mainly composed of a vinyl aromatic hydrocarbon or a polymer block mainly composed of a conjugated diene, it is copolymerized. Even if the vinyl aromatic hydrocarbons are evenly distributed in the polymer block,
It may be distributed in a taper (gradual decrease) shape. The copolymer portion may have a plurality of portions where vinyl aromatic hydrocarbons are uniformly distributed and / or a plurality of portions where the vinyl aromatic hydrocarbons are distributed in a tapered shape.

The block copolymer used in the present invention can be basically produced by a conventionally known method.
No. 9286, JP-B-43-17979, JP-B-48-2423, JP-B-49-36957, JP-B-57-49567, and JP-B-58-11.
The method described in Japanese Patent Application Publication No. 446/446 may be mentioned, but production conditions must be set for each constituent polymer so as to satisfy the requirements described below. All of the above-mentioned known methods are methods of block copolymerizing a conjugated diene and a vinyl aromatic hydrocarbon using an anionic initiator such as an organic lithium compound in a hydrocarbon solvent.

The vinyl aromatic hydrocarbon used in the present invention includes styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinyl There are anthracene and 1,1-diphenylethylene, and styrene is a typical example. These may be used alone or in combination of two or more.

The conjugated diene is a diolefin having a pair of conjugated double bonds, for example, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene),
Examples thereof include 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and 1,3-hexadiene, and typical examples thereof include 1,3-butadiene and isoprene. These may be used alone or in combination of two or more.

As the hydrocarbon solvent, butane, pentane,
Aliphatic hydrocarbons such as hexane, isopentane, heptane and octane, cyclopentane, methylcyclopentane,
Alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and ethylcyclohexane, and aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene can be used. These may be used alone or in combination of two or more.

The organic lithium compound is an organic monolithium compound, an organic dilithium compound, or an organic polylithium compound having one or more lithium atoms bonded in a molecule.
Specific examples of these include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, hexamethylene dilithium, butadienyl dilithium, isoprenyl dilithium and the like. No. These may be used alone or in combination of two or more.

The polymerization temperature for producing the polymer in the method of the present invention is generally from -10 ° C to 150 ° C, preferably from 40 ° C to 120 ° C. The time required for the polymerization varies depending on the conditions, but is usually within 48 hours, particularly preferably 1 to 10 hours. Further, it is desirable to replace the atmosphere of the polymerization system with an inert gas such as nitrogen gas. The polymerization pressure is not particularly limited, as long as it is a pressure range sufficient to maintain the monomer and the solvent in a liquid phase within the above-mentioned polymerization temperature range. Furthermore, it is necessary to take care that impurities such as water, oxygen, carbon dioxide, etc. which inactivate the catalyst and the living polymer do not enter the polymerization system.

The preferred range of the vinyl aromatic hydrocarbon content of the block copolymer used in the present invention is 65% by weight or more and 80% by weight or less, and the more preferred range is 65% by weight or more and 75% by weight or less. . If the vinyl aromatic hydrocarbon content of the block copolymer is less than 65% by weight, the rigidity of the resin composition molded article is inferior, and if it exceeds 80% by weight, the surface impact resistance is undesirably reduced. On the other hand, when the content of the vinyl aromatic hydrocarbon in the block copolymer of the present invention is out of the range, the molded product becomes pale and unfavorable.

The preferred range of the block ratio of the vinyl aromatic hydrocarbon polymer block of the block copolymer used in the present invention is 50% by weight or more and 80% by weight or less, and the more preferred range is 55% by weight or more and 75% by weight. % Or less.
When the block ratio is 50% by weight or less, the rigidity of the resin composition molded article and the surface impact resistance at -10 ° C or less are inferior, and 80% by weight.
Exceeding the surface impact resistance is undesirably reduced. The block ratio of the vinyl aromatic hydrocarbon block is determined by the weight and weight ratio of the vinyl aromatic hydrocarbon and the conjugated diene in the step of copolymerizing at least a portion of the vinyl aromatic hydrocarbon and the conjugated diene during the production of the block copolymer. Can be controlled by changing the polymerization reactivity ratio and the like.

As a specific method, (a) a mixture of a vinyl aromatic hydrocarbon and a conjugated diene is continuously supplied to a polymerization system for polymerization, and / or (b) a polar compound or a randomizing agent. And the method of copolymerizing a vinyl aromatic hydrocarbon and a conjugated diene using the above method. Examples of polar compounds and randomizing agents include tetrahydrofuran, diethylene glycol dimethyl ether, ethers such as diethylene glycol dibutyl ether, amines such as triethylamine, tetramethylethylenediamine, thioethers, phosphines, phosphoramides, alkylbenzene sulfonates, potassium and sodium salts. Alkoxide and the like. In the present invention, the block ratio of the vinyl aromatic hydrocarbon polymer block incorporated in the block copolymer refers to the oxidation of the block copolymer by di-tert-butyl hydroperoxide using osmium tetroxide as a catalyst. Decomposition method (IM KO
LTHOFF, et al. , J. et al. Polym. Sci.
1,429 (1946)), and a vinyl aromatic hydrocarbon polymer block component (excluding a vinyl aromatic hydrocarbon polymer component having an average degree of polymerization of about 30 or less) was quantified. The block rate (% by weight) means that the weight% of the vinyl aromatic hydrocarbon polymer block in the block copolymer is X, and the weight% of all the vinyl aromatic hydrocarbons in the block copolymer is Y. , (X / Y) × 100
Means the value obtained from the above equation.

The molecular weight distribution of the vinyl aromatic hydrocarbon polymer block is a value obtained by reducing the weight average molecular weight of the same component as that used for the determination of the block ratio by the number average molecular weight. The weight-average molecular weight and the number-average molecular weight are determined by preparing a calibration curve of the peak count number and the number-average molecular weight of the monodisperse polystyrene by gel permeation chromatography (GPC). Gel chromatography <basic edition>, published by Kodansha).

In the present invention, the preferred molecular weight distribution (weight average molecular weight is
The range of the value (reduced by the average molecular weight) exceeds 1.6 and 3.0.
The value is more preferably 1.7 or more and 2.5 or less.
When the molecular weight distribution of the vinyl aromatic hydrocarbon polymer block is 1.6 or less, the surface smoothness of the resin composition is inferior,
If it exceeds 3.0, the surface impact resistance at −10 ° C. or lower is inferior, so that it is not preferable. Further, a component having a molecular weight of 60,000 or more of the vinyl aromatic hydrocarbon polymer block is 15% by weight or more,
It is preferably at most 60% by weight, more preferably at least 20% by weight and at most 55% by weight. When the amount of the component having a molecular weight of 60,000 or more of the vinyl aromatic hydrocarbon polymer block is less than 15% by weight, the surface smoothness of the resin composition molded article is poor, and when it exceeds 60% by weight, the surface impact resistance at -10 ° C or less is poor. Therefore, it is not preferable. Incidentally, the vinyl aromatic hydrocarbon polymer block may be monomodal, bimodal or polymodal. In bimodal or polymodal, the peak molecular weight on the high polymer side can be reduced to 100,000 or less. It is preferable for exhibiting impact properties.

The molecular weight of the block copolymer used in the present invention can be arbitrarily adjusted depending on the amount of the catalyst used for the polymerization. From the viewpoint of moldability, a melt flow index (measured according to JIS K-6870), which is one measure of molecular weight.
The conditions are G conditions, temperature 200 ° C, weight 5Kg) 0.1 ~
50 g / 10 min, preferably 1 to 20 g / 10 mi
n.

If desired, the block copolymer used in the present invention can be hydrogenated in an inert solvent in the presence of a hydrogenation catalyst and used as a hydrogenated product. Specific methods are disclosed in JP-B-42-8704 and JP-B-43-66.
No. 36, particularly preferably Japanese Patent Publication No. Sho 6
This method is described in JP-A-3-4841 and JP-B-63-5401.

The monomer constituting the vinyl aromatic hydrocarbon- (meth) acrylate copolymer of the component (b) used in the present invention includes, for example, styrene, α-methyl Styrene, p-methylstyrene, pt-butylstyrene and the like, and as the (meth) acrylate, methyl methacrylate, ethyl ester, n-butyl ester, i-butyl ester, t-butyl ester, Esters of (meth) acrylic acid and alcohols having 1 to 8 carbon atoms, such as 2-ethylhexyl ester, acrylic acid methyl ester, ethyl ester, n-butyl ester and 2-ethylhexyl ester.

As the component (b), a styrene-n-butyl acrylate copolymer is preferable in order to maintain high transparency and rigidity in the polymer and at the same time to improve processability. To improve rigidity and heat resistance, a styrene-methyl methacrylate copolymer is preferable, but if it is blended in a large amount, transparency becomes slightly inferior. In the styrene-methyl methacrylate copolymer and the styrene-n-butyl acrylate copolymer, the copolymerization ratio of methyl methacrylate or butyl acrylate is set at 8 in order to eliminate the paleness of the final composition.
It is preferably from 25 to 25% by weight, more preferably from 10 to 23% by weight, but may contain 0.1 to 2% of another monomer. MI (G) of these vinyl aromatic hydrocarbon- (meth) acrylate copolymers is 1 to 1
0 g / 10 min is preferable.

The rubber-modified impact-resistant polystyrene of the component (c) used in the present invention is obtained by dissolving a butadiene-based rubber-like polymer in styrene, then initiating the polymerization of styrene, and graft-polymerizing styrene onto the rubber-like polymer. The rubber particles formed by the grafted rubbery polymer have an average particle size of 1.5 μm or more and 8.0 μm or less, preferably 1.8 μm or more and 5.0 μm or less. Are more preferred.

The term "average particle diameter" as used herein means a transmission electron micrograph of a rubber-modified impact-resistant polystyrene by a thin section method, and measures the particle diameter of about 500 rubber particles in the photograph. Particle size = (ΣniDi ⁴ ) / (ΣniD
i ³ ) (where ni is the number of rubber particles whose major axis is Di). These rubber particles have a so-called salami structure or a core-shell structure in which a polystyrene portion is incorporated therein.

Rubber-modified impact-resistant polystyrene having an average particle size of less than 1.5 μm is not preferable because the effect of improving the surface impact resistance is small. Further, rubber-modified impact-resistant polystyrene having an average particle size of more than 8.0 μm is not preferable because the haze value becomes high and the transparency becomes extremely poor. To control the average particle size of the rubber particles, the composition of the rubbery polymer dissolved in styrene, the degree of polymerization, the stirring state when polymerizing styrene, the polymerization initiator, the chain transfer agent, the graft ratio of rubber particles and the crosslinking It is possible by appropriately changing the degree.

A block copolymer elastomer of a vinyl aromatic hydrocarbon and a conjugated diene of the component (d) used in the present invention.
Has a vinyl aromatic hydrocarbon content of at least 10% by weight,
% By weight or less is preferred. If the content of the vinyl aromatic hydrocarbon is less than 10%, the compatibility with the components (a) and (b) is poor, and the transparency is remarkably deteriorated. If the content of the vinyl aromatic hydrocarbon exceeds 50%, the effect of improving the surface impact resistance is undesirably small.

The block copolymer (a) of the transparent high impact resin composition of the present invention and vinyl aromatic hydrocarbon- (meth)
The weight ratio of the acrylate copolymer resin (b) is
(A) = 10 with respect to (a) + (b) = 100 parts by weight
Not less than 90 parts by weight, (b) is not more than 90 parts by weight, not less than 10 parts by weight, preferably (a) is not less than 20 parts by weight and not more than 80 parts by weight, (b) is not more than 80 parts by weight,
20 parts by weight or more. When the weight ratio of the block copolymer (a) is less than 10 parts by weight, the surface impact resistance of the molded article of the resin composition is unpreferably reduced. On the other hand, when the amount exceeds 90 parts by weight, the rigidity of the molded article of the resin composition is lowered, and the moldability is deteriorated.

The mixing ratio of the rubber-modified impact-resistant polystyrene (c) is from 0.3 to 10 parts by weight based on (a) + (b) = 100 parts by weight. 0.5 parts by weight or more and 8 parts by weight or less. When the component (c) is less than 0.3 parts by weight, the effect of improving the surface impact resistance is hardly obtained, which is not preferable. On the other hand, if the amount exceeds 10 parts by weight, the haze value of the molded article of the resin composition becomes high and the transparency is remarkably deteriorated.

The addition and mixing ratio of the block copolymer elastomer (d) of the vinyl aromatic hydrocarbon and the conjugated diene is as follows.
(A) + (b) = 1.0 to 20 parts by weight based on 100 parts by weight, preferably 3.0 to 18 parts by weight. When the amount of the component (d) is less than 1.0 part by weight, the effect of improving the surface impact resistance is hardly obtained, which is not preferable. On the other hand, when the amount exceeds 20 parts by weight, the haze value of the molded article of the resin composition becomes high and the transparency is remarkably deteriorated. The component (C) and the component (D) can be used in combination as needed as long as transparency and surface impact resistance are not impaired.

Various additives can be added to the transparent high impact resin composition of the present invention, if necessary, as long as the transparency, rigidity and surface impact resistance are not impaired. These additives include non-rubber-modified polystyrene and other polymers that do not impair transparency, antioxidants, antistatic agents, antifogging agents, ultraviolet absorbers, lubricants, coloring agents, mineral oils, plasticizers, and the like. is there. The method for obtaining the transparent high impact resin composition of the present invention can be produced by any conventionally known compounding method. For example, there are a melt kneading method using a general kneader such as an open roll, an intensive mixer, an internal mixer, a co-kneader, a continuous kneader equipped with a twin-screw rotor, and an extruder.

[0034]

EXAMPLES Examples of the present invention will be described below, but they do not limit the scope of the present invention. Production of block copolymer of component (a) Table 1 shows the block copolymer of component (a) used in the examples. The block copolymers of A-1 to A-12 are AB
-A 'block copolymer, n-butyllithium is used as an initiator in a cyclohexane solvent, styrene, a styrene / butadiene mixture, and a styrene solution of styrene are added in the order of styrene to polymerize and polymerize with methanol. After stopping, 2- (2-hydroxy-3-t
-Butyl-5-methylbenzyl) -4-methyl-6-t
-Butylphenyl acrylate and trisnonylphenyl phosphite were added as stabilizers in an amount of 0.5 part by weight based on 100 parts by weight of the block copolymer, and the solvent was distilled off. The content (% by weight) of the block polystyrene was determined by decomposing the block copolymer with osmic acid.
It was measured after reprecipitation in methanol. Further, the molecular weight distribution (Mw / Mn) of the block styrene was determined from the GPC curve of the block styrene, and the amount (% by weight) of the block styrene having a molecular weight of 60000 or more was calculated from the area ratio of the block styrene GPC curve. Melt flow (MI) was measured under G conditions. The Mw / Mn of the block styrene of the block polymer and the amount of the component having a molecular weight of 60,000 or more were adjusted by controlling the composition ratio of the amount of the styrene monomer, the number of stirring of the stirring blade of the polymerization vessel, the polymerization temperature, and the like. The block copolymer A-13 is C-A-
A block copolymer having a BA ′ structure was obtained in the same manner as in A-1, except that a monomer was added so that the ribtadiene portion C occupies 8% by weight of the block polymer. Was. The block copolymers A-14 and A-15 were polymerized by adding n-butyllithium and styrene in a cyclohexane solvent in the first stage, and polymerized by adding n-butyllithium and styrene in the second stage. And then styrene
After completion of the polymerization by adding a butadiene mixture, a radial block copolymer obtained by adding 1,3 bis (N, N-glycidylaminomethyl) cyclohexane as a coupling agent is used in the same manner as A-1. A block copolymer was obtained.

Preparation of Component (b) Table 2 shows the component (b) used in the examples. B-1 is a commercially available product, and B-2 to B-5 are styrene and n-butyl acrylate in a 10 L autoclave with a stirrer.
5 kg was added at the rate shown in FIG.
A predetermined amount of 1,1 bis (t-butylperoxy) cyclohexane was charged to adjust 3 kg and MI (G), and 11
After polymerization at 0 ° C. for 2 hours, 130 ° C. for 3 hours, and 150 ° C. for 2 hours, unreacted styrene, n-butyl acrylate, and ethylbenzene were recovered by an extruder to obtain.

Preparation of rubber-modified impact-resistant polystyrene of component (c) Table 3 shows the rubber-modified impact-resistant polystyrene of component (c) used in the examples. The rubber-modified impact-resistant polystyrene shown in Table 3 is obtained by dissolving the rubber shown in Table 3 in styrene monomer.
Polymers were polymerized in a reaction vessel equipped with a stirring blade, and unreacted monomers and the like were removed under reduced pressure. The average particle diameter of the rubber particles was adjusted by changing the rotation speed of the stirring blade.

The following components were used as the component (d). D-1: Asahi Kasei Kogyo Co., Ltd. Tafprene 125, styrene content 40% D-2: Asahi Kasei Kogyo Co., Ltd. tufprene A, styrene content 40% The evaluation method in the present invention is as follows. [Tensile Modulus] In accordance with JIS K-6872, it was measured in a sheet extrusion direction and a direction perpendicular to the sheet extrusion direction (unit: Kg / cm ² ).

[Surface Impact Strength] The surface impact strength was measured using ASTM D except that the weight had a radius of 1/2 inch.
It measured according to -1709 and calculated | required the 50% destruction value (unit is Kg * cm). [Transparency] The haze was measured according to JIS K-6714. [Roughness of skin] The extruded sheet (thickness: about 0.7 mm) was determined from the transmittance at a wavelength of 700 nm using an ultraviolet spectrophotometer (UV-2100, manufactured by Shimadzu Corporation).

：: transmittance is 85% or more Δ: transmittance is 80% or more and less than 85% ×: transmittance is less than 80% [Bluishness] The molded sheet was visually judged.

[0040]

Examples 1 to 16 and Comparative Examples 1 to 8 Component (a), component (b), component (c) or component (c) having the compounding amount (parts by weight) shown in Tables 4, 5 and 6 The resin composition obtained in d) was formed into a sheet having a thickness of about 0.7 mm using a 40 mm sheet extruder, and the surface impact strength, the haze value, and the degree of skin roughness representing surface smoothness were measured.

The results are shown in Tables 4, 5 and 6. It can be seen that the composition within the range specified in the present invention has a transparent feeling due to good surface smoothness of the molded sheet, and is extremely excellent in impact resistance.

[0042]

Examples 17 to 30, and Comparative Examples 9 to 23 The components (a) having the compounding amounts (parts by weight) shown in Tables 7, 8 and 9;
A resin composition comprising the component (b), the component (c) and / or the component (d) was prepared in the same manner as in Example 1 to a thickness of about 0.7 mm.
, And measured for tensile modulus, surface impact strength, skin roughness, and bluish whiteness.

The results are shown in Tables 7, 8 and 9. It can be seen that the composition within the range specified in the present invention has a very small bluish whiteness of the molded sheet, has a good surface smoothness, has transparency, is extremely excellent in impact resistance, and is excellent in balance with rigidity. In addition, it can be seen that it is particularly excellent in low-temperature impact resistance.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

[0048]

[Table 5]

[0049]

[Table 6]

[0050]

[Table 7]

[0051]

[Table 8]

[0052]

[Table 9]

[0053]

The molded article of the resin composition of the present invention has excellent transparency with a smooth surface without bluish whiteness, high rigidity, not only surface impact resistance at room temperature but also -10 ° C. or less. It has the performance which also has good surface impact resistance even at the above temperature. Therefore, the resin composition of the present invention makes use of such properties, and the case for foods in which the contents look vivid,
It is suitable for applications such as packaging materials and blisters.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-298556 (JP, A) JP-A-4-220450 (JP, A) JP-A-62-115053 (JP, A) JP-A-57-1982 JP-A-51-89550 (JP, A) JP-A-7-179696 (JP, A) JP-A-7-268175 (JP, A) JP-A-6-184400 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 53/02

Claims (6)

(57) [Claims] (1) The following component (a) is used in an amount of 10 parts by weight or more,
A transparent high-impact resin composition comprising component (c) and / or component (d) in a composition consisting of 0 part by weight or less and component (b) of 10 parts by weight or more and 90 parts by weight or less. object.
(A) a block copolymer consisting of at least two polymer blocks A mainly composed of vinyl aromatic hydrocarbons and at least one polymer block B mainly composed of conjugated dienes; The vinyl aromatic hydrocarbon content is 65% by weight or more and 80% by weight or less, and the block ratio of the vinyl aromatic hydrocarbon polymer block incorporated in the block copolymer is 50% by weight or more and 80% by weight or less, Weight average of the vinyl aromatic hydrocarbon polymer block
A block copolymer having a molecular weight distribution, which is a value obtained by reducing the molecular weight by a number average molecular weight, exceeding 1.6 and having a component having a molecular weight of 3.0 or less and having a molecular weight of 60,000 or more, from 15% by weight to 60% by weight, (b) (C) a vinyl aromatic hydrocarbon- (meth) acrylate copolymer resin having a content of (meth) acrylic ester of 8% by weight or more and 25% by weight or less;
Rubber-modified impact-resistant polystyrene obtained by graft-polymerizing styrene to a butadiene-based rubbery polymer, (d) a content of vinyl aromatic hydrocarbon of 10% by weight or more and 50% by weight
The following vinyl aromatic hydrocarbon and conjugated diene block copolymer elastomer, 2. The transparent high impact resin composition according to claim 1, wherein the (meth) acrylate of component (b) is n-butyl acrylate. 3. The rubber particles of the rubber-modified impact-resistant polystyrene of the component (c) have an average particle size of 1.5 μm or more and 8.0 μm or more.
The transparent high-impact resin composition according to claim 1, wherein: 4. The compounding amount of the rubber-modified impact-resistant polystyrene of the component (c) is 0.3 to 10 parts by weight based on 100 parts by weight of the component (a) + the component (b). The transparent high-impact resin composition according to claim 1. 5. The transparent high impact resin composition according to claim 1, wherein the vinyl aromatic hydrocarbon as the component (d) is styrene. 6. The compounding amount of the block copolymer elastomer of the component (d) is 1.0 to 20 parts by weight based on 100 parts by weight of the component (a) + the component (b). The transparent high-impact resin composition according to claim 1.