JPH021183B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a graft copolymer resin composition obtained by copolymerizing an ethylene-α-olefin rubber with a monomer mixture containing an aromatic vinyl compound and a vinyl cyanide compound as main components, and a diene rubber. The present invention relates to a thermoplastic resin composition with improved colorability and excellent weather resistance and impact resistance, which is made of a graft copolymer resin composition obtained by copolymerizing a monomer mixture containing a methacrylic acid ester compound as a main component. Ethylene-α-olefin rubber For example, a copolymer obtained by graft copolymerizing a monomer mixture containing an aromatic vinyl compound and a vinyl cyanide compound to ethylene-propylene rubber, or a copolymer thereof and aromatic vinyl. Resin composition (A) consisting of a copolymer of a compound and a vinyl cyanide compound (AES resin)
is a resin suitable for injection molding and extrusion molding because it has excellent moldability, molded appearance, impact resistance, heat resistance, mechanical strength, and chemical resistance. Furthermore, since there are no double bonds in the main chain of the rubber-like polymer, it has excellent weather resistance. However, conventional methods have had the problem of poor coloring properties. The method for coloring the molding material is to mix coloring agents such as organic or inorganic pigments or dyes, dispersants, lubricants, etc. with the resin as necessary, melt and knead the pellets to form colored pellets, and then mold the pellets. is common. Regarding the colorability in these methods, there is a tendency that some colors are easy to express and others are difficult to express depending on the color feeling and transparency of the material itself, and it is difficult to objectively determine the quality of the material itself. There is a problem with this. However, rubber-modified resins such as ABS resins are said to have slightly inferior coloring properties in certain color tones compared to homogeneous resins. According to the inventors' investigation, AES resin is superior to other rubber-modified resins.
Compared to ABS resin, it tends to lack sharpness and depth, especially in vivid colors, deep colors, and blackened tones, and requires a large amount of colorant to achieve the same level of color depth. showed that. As a result of intensive studies on these points, we found that the resin composition (A) and a copolymer obtained by graft copolymerizing a monomer mixture containing a methacrylic acid ester compound as a main component to a diene rubber, or a copolymer obtained by graft copolymerizing the resin composition (A) with a monomer mixture containing a methacrylic acid ester compound as a main component, or a copolymer of the same and methacrylic acid. The inventors have discovered that colorability can be improved by blending a resin composition () consisting of an ester homopolymer or copolymer in a specific ratio, leading to the present invention. That is, the present invention is a graft copolymer resin composition (A) 80 to 40 obtained by copolymerizing an ethylene-α-olefin rubber with a monomer mixture containing an aromatic vinyl compound and a vinyl cyanide compound as main components. weight% and
Adding methacrylic acid ester compound to diene rubber
Graft copolymer resin composition (B) 20 to 60% by weight obtained by copolymerizing a monomer mixture consisting of 55% by weight or more of an aromatic vinyl compound and a vinyl cyanide compound in a total amount of 55% by weight or more It is a thermoplastic resin composition consisting of. The resin composition of the present invention has superior coloring properties compared to conventional AES resins, and can produce vivid colors and black tints that were difficult to express with conventional AES resins. The amount of pigment required for Moreover, the resin composition of the present invention has excellent weather resistance even when blended with the graft resin composition (B) using a rubber-modified resin based on diene rubber as a rubbery polymer, which is a characteristic of AES resin. is almost never damaged. The resin composition (A) used in the present invention is prepared in the presence of an ethylene-α-olefin rubber such as an ethylene-propylene copolymer, an ethylene-propylene-nonconjugated diene copolymer, or an ethylene-butylene copolymer. A graft copolymer obtained by copolymerizing a monomer mixture whose main components are an aromatic vinyl compound and a vinyl cyanide compound, or a resin comprising a copolymer of the graft copolymer and the monomer mixture. It is a composition. AES resin, which is a typical resin of resin composition (A), can be produced by various methods in which vinyl monomers are radically polymerized in the presence of rubber, such as emulsion polymerization, bulk polymerization, and suspension polymerization. It can be manufactured with etc. The intrinsic viscosity [y] (methyl ethyl ketone, 30 DEG C.) of the matrix resin (solvent soluble component) in the resin composition (A) is preferably in the range of 0.3 to 0.8. Aromatic vinyl compounds used as monomers include styrene, α-methylstyrene, and P-methylstyrene. The vinyl cyanide compound is selected from acrylonitrile, methacrylonitrile, and the like. Furthermore, a small amount of vinyl compounds copolymerizable with these, such as alkyl acrylates and alkyl methacrylates, may be used in combination. The rubber content in the AES resin used in the present invention is 10
A suitable range is 60% by weight, more preferably 15% to 50% by weight. Resin composition used in combination with AES resin
(B) is obtained by copolymerizing a monomer mixture consisting of 45% by weight or more of a methacrylic acid ester compound and 55% by weight or less of an aromatic vinyl compound and a cyanvinyl compound in total in the presence of a diene rubber. This is a resin composition that does not contain the obtained graft copolymer or a homopolymer of the same and a methacrylic acid ester compound and/or a copolymer of the above monomer mixture. As for the production method, it can be produced by various methods such as radical polymerization of vinyl monomers in the presence of rubber, such as emulsion polymerization method, bulk polymerization method, suspension polymerization method, and solution polymerization method. Diene rubbers used in the resin composition (B) of the present invention include butadiene rubber, styrene-butadiene copolymer rubber, isoprene rubber, and the like. The methacrylic acid ester compounds used as monomers include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, and isopropyl methacrylate. Further, a methacrylic acid ester compound whose polymer has a glass transition temperature of room temperature or higher is preferred, and methyl methacrylate (MMA), which has a high glass transition temperature, is particularly preferred. Specific examples of the aromatic vinyl compound include styrene, α-methylstyrene, etc. Among these, styrene is preferred. Further, a specific example of the vinyl cyanide compound is acrylonitrile. The resin composition (B) of the present invention is obtained by graft copolymerizing a monomer containing the above-mentioned methacrylic acid ester compound, aromatic vinyl compound, and vinyl cyanide compound as essential components to a diene rubber. . If both the aromatic vinyl compound and the vinyl cyanide compound are not included, the balance between processability and impact resistance will be poor, and especially if the vinyl cyanide compound is not included, the impact resistance will be poor. of the matrix resin component in the resin composition (B)
The MMA content is preferably 45% by weight or more, more preferably 50% by weight or more, particularly preferably 55% by weight or more. If the MMA content is low, coloring properties, weather resistance, etc. will be significantly reduced, making it difficult to obtain the effects of the present invention. Furthermore, the total amount of aromatic vinyl compounds and vinyl cyanide compounds in the resin components excluding the diene rubber in the resin composition (B) is 55% by weight or less, preferably 50% by weight or less, more preferably 45% by weight or less. The content of vinyl cyanide compound is preferably 3 to 35% by weight, more preferably 10 to 25% by weight. Preferred monomer combinations include MMA-styrene-acrylonitrile. The blending ratio of the resin composition (A) and the resin composition (B) is in the range of 80:20 to 40:60, preferably 80:20 to 45:55, by weight. If the amount of AES resin exceeds this range, the colorability, which is a feature of the present invention, will hardly be improved. On the other hand, if the amount of AES resin is less than this range, the impact resistance, shock resistance, and weather resistance will be lowered, which is not desirable. The resin composition (A) and the resin composition (B) may be mixed together in a solution-solution or solution-latex state after polymerization, and then the resin composition may be recovered. Alternatively, both may be mixed in the form of powder-powder, powder-pellet, pellet-pellet, or the like. During mixing or pelletizing, commonly used antioxidants, lubricants, etc. can also be added. Also, as long as it does not significantly impair the effects of the present invention.
Resins such as ABS and HIPS can also be mixed and used in the composition of the present invention. Next, the present invention will be specifically explained using examples. Incidentally, the AES resin used in the examples was manufactured by the following method. Manufacture of AES resin <AES polymer No. 1> Preliminarily make a homogeneous solution in a stainless steel autoclave with an internal volume of 50 and equipped with a ribbon-type stirring blade.Iodine value is 15, Mooney viscosity is 42, and 5-ethylidene-2-norbornene is used as the diene component. 20 parts by weight of EPDM (JSR EP22 manufactured by Japan Synthetic Rubber Co., Ltd.), 56 parts by weight of styrene
parts by weight, 120 parts by weight of toluene, and 0.1 parts by weight of tertiary decyl mercaptan were charged, the temperature was raised while stirring, and at 50°C, 24 parts by weight of acrylonitrile, 0.5 parts by weight of benzoyl peroxide, and 0.1 parts by weight of dicumyl peroxide were added. The temperature further increases to 80
After reaching the temperature, the polymerization reaction is carried out at a stirring speed of 100 rpm while controlling the temperature to be constant at 80°C. 120℃ for 1 hour from 6 hours after the start of the reaction
The temperature was raised to 100.degree. C., and the reaction was continued for an additional 2 hours to complete the reaction.
The polymerization rate was 97%. After cooling to 100℃,
2,2'-methylene-bis(4-methyl-6-t-
After adding and mixing 0.2 parts by weight (butylphenol), the reaction mixture was extracted from the autoclave,
Most of the unreacted monomers and solvent are distilled off by steam distillation, and after finely pulverized, the volatile matter is substantially distilled off using a 40 mmφ vented extruder (220°C, >700 mmHg vacuum) and the polymer is pelleted. It was recovered as. <AES Polymer No. 2> A polymer was obtained in the same manner as <AES Polymer No. 1> above, except that 40 parts by weight of EPDM, 42 parts by weight of styrene, 18 parts by weight of acrylonitrile, and 150 parts by weight of toluene were used. Manufacturing method of resin composition (B) <Polymer No. 1> 20 parts by weight of butadiene rubber (JSR BR02 manufactured by Japan Synthetic Rubber Co., Ltd.) made into a homogeneous solution in advance in a stainless steel autoclave with an internal volume of 50 mm equipped with a ribbon-type stirring blade. , 48 parts by weight of methyl methacrylate, 24 parts by weight of styrene
Parts by weight, 8 parts by weight of acrylonitrile, Toluene
100 parts by weight, tertiary lead decyl mercaptan
Add 0.5 parts by weight of dicumyl peroxide, raise the temperature to 50°C while stirring, and add 0.05 parts by weight of dicumyl peroxide.
After the temperature was further increased to 120°C, the reaction was carried out for 10 hours at a stirring rotation speed of 100 rpm while controlling the temperature to be constant at 120°C. The polymerization yield was 95%. The subsequent treatments were performed in the same manner as <AES Polymer No. 1> to obtain a polymer. <Polymer No. 2> Except that 32 parts by weight of methyl methacrylate, 36 parts by weight of styrene, and 12 parts by weight of acrylonitrile were used.
A polymer was obtained in the same manner as Polymer No. 1>. <Polymer No. 3> After sufficiently replacing the inside of a stainless steel reactor with a stirrer with nitrogen, add 20 parts by weight (as solid content) of polybutadiene latex (JSR0700 manufactured by Japan Synthetic Rubber Co., Ltd.) and 200 parts by weight of ion-exchanged water in a nitrogen stream. 24 parts by weight of styrene, 48 parts by weight of methyl methacrylate, 8 parts by weight of acrylonitrile, 0.2 parts by weight of tertiarydecyl mercaptan, 0.4 parts by weight of sodium formaldehyde sulfonate dihydrate, Sodium ethylenediaminetetraacetate 0.2 parts by weight, ferrous sulfate 0.01 parts by weight, cumene hydroperoxide
Add 0.3 parts by weight. 4 at 60℃ with continuous stirring.
A time polymerization reaction was carried out. The polymerization conversion rate at that time is
It was 95%. After coagulating using an aqueous sulfuric acid solution,
A polymer was obtained by dehydration and drying. <Polymer No. 4> 40 parts by weight of polybutadiene latex (as solid content) 36 parts by weight of methyl methacrylate, styrene
<Polymer No. 3> above except that 18 parts by weight, 6 parts by weight of acrylonitrile, and 150 parts by weight of ion-exchanged water were used.
A polymer was obtained in the same manner as above. <Polymer No. 5> Same as <Polymer No. 3> above except that 40 parts by weight of polybutadiene latex (as solid content), 42 parts by weight of methyl methacrylate, 18 parts by weight of styrene, and 150 parts by weight of ion-exchanged water were used. A polymer was obtained by the method. Examples AES resin pellets obtained by the above method and pellets of resin composition (B) were melt-kneaded in a 40 mmφ extruder (220°C) to obtain resin compositions as shown in Table 1. Test pieces were molded using a 90TON injection molding machine (220°C) and their physical properties were measured. The resulting resin composition was blended as shown below and passed through an extruder to obtain colored pellets, which were then injection molded to obtain a color tone evaluation plate. For black formulations, the brightness was measured using a color difference meter and expressed in Munsell color table values. For other color combinations, saturation was visually determined. Black compound resin 100 Carbon black 0.5 Ca stearate 0.3 Red compound resin 100 Red red 1.0 Ca stearate 0.5 Blue compound resin 100 Ultramarine blue 1.0 Ca stearate 0.5 For weather resistance, use the Sunshine Weatherometer.
Izod Imp was measured after 1000 hours of irradiation. The results are shown in Tables 1, 2 and 3. Notes for Tables 1, 2 and 3 Melt index: ASTM D-1238 200℃
5Kg/ ^cm2Izotsut Impact: ASTM D-256-56
(Cross section 1/4 x 1/2 inch with notch) Weather resistance: Sunshine weather meter conditions Black panel temperature 63℃ Rainfall cycle 18
Minutes/120 minutes Izod Imp…ASTMD―
256-56 (1/8 x 1/2 inch cross section, no notch, -30℃) PAS resin: Styrene-acrylonitrile copolymer LITAC-A-120pc manufactured by Mitsui Toatsu Co., Ltd. ABS resin: JSR ABS manufactured by Japan Synthetic Rubber Co., Ltd. 10 MS resin: Styrene-methyl methacrylate copolymer Sebian MAS30 manufactured by Daicel Corporation In the formulations of Examples 1 to 4, it was mentioned as a reference example.
Blackness and saturation comparable to ABS resin were obtained.
On the other hand, in Comparative Examples 1 and 2, examples of AES resin alone were given, but in this case, compared to the ABS resin mentioned in the reference example, the blackness of the black formulation was slightly lower, and the color feeling was different for the red and blue formulations, but Munsell color. The color saturation was lower than that seen on the table. Furthermore, in Comparative Examples 3 and 4, examples were given in which the methyl methacrylate copolymer resin alone was used, but it can be seen that in this case, although the coloring property was excellent, the weather resistance was significantly inferior. In Comparative Example 5, an AES resin beyond the range of the present invention was blended, but no improvement was observed in coloring properties, while in Comparative Example 6, AES resin was blended beyond the range of the present invention.
Although it contains a resin, the colorability is improved, but the weather resistance is greatly reduced. In Comparative Example 7, the MMA content in the matrix resin of the resin composition (B) was less than 50% by weight, but it was found that the effect of improving colorability was small and the weather resistance was poor.

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Claims (1)

[Claims] 1 80 to 40% by weight of a graft copolymer resin composition (A) obtained by copolymerizing an ethylene-α-olefin rubber with a monomer mixture containing an aromatic vinyl compound and a vinyl cyanide compound as main components. , a graft copolymer obtained by copolymerizing a diene rubber with a monomer mixture consisting of 45% by weight or more of a methacrylic acid ester compound and a total amount of 55% by weight or less of an aromatic vinyl compound and a vinyl cyanide compound. A thermoplastic resin composition comprising 20 to 60% by weight of resin composition (B).