JP5776391B2 - Heat-resistant and paint-resistant thermoplastic resin composition - Google Patents

Description

  The present invention relates to a thermoplastic resin composition that has both good fluidity and impact resistance while having high heat resistance, and can obtain a coated molded article having a good coating film appearance.

  Rubber-reinforced styrene-based resins have excellent processability, impact resistance, and mechanical properties, so they are used as molding materials for various components in a wide range of fields such as the vehicle field, home appliance field, and building material field. ing. For example, in recent years, in the vehicle field, attention has been focused on the excellent secondary processability of rubber-reinforced styrene-based resins, especially heat resistance, and development of use for four-wheel interior members, rear spoilers, and the like has been made.

  On the other hand, there is a strong demand for reduction in coating failure (paint resistance) of molded products at all times. A rubber-reinforced styrene resin is a material that is generally easy to paint, but may be affected by factors such as the characteristics of the resin composition, molding conditions, coating method, and coating environment, and may cause a significant coating failure. Among these poor coatings, a suction phenomenon that occurs when solvent components such as thinner contained in the paint act on the molded product (a phenomenon in which fine irregularities are formed on the painted surface and uneven gloss is observed due to irregular reflection of light). The blister phenomenon (a phenomenon in which a small hole with a shape like a crater is generated on the paint surface) that is particularly common at the edge of injection-molded products is cited as a typical paint defect, which increases the commercial value of the final product. It is a loss.

  The following techniques are disclosed as techniques for reducing past coating defects.

  Patent Documents 1 and 2 propose a technique for improving paint resistance and improving suction by using an AS resin having a high content of acrylonitrile as a matrix component of a rubber-reinforced styrene resin. However, when the present technology is applied to a heat-resistant rubber-reinforced styrene-based resin, the fluidity is lowered, so that it is not suitable for injection molding, and the blister phenomenon has not been solved at all.

  Patent Document 3 proposes a technique of using different rubber component particle diameters in order to reduce plating streak and paint resistance and reduce silver streak. However, in this technique, the impact of the resin composition is high and useful for the appearance of plating, but it has not been able to solve the suction of paint and the blister phenomenon.

  In Patent Document 4, a resin to which an AS resin in which the molecular weight distribution of acetone-soluble components is controlled to a specific range is applied to components other than rubber in the rubber-reinforced styrene resin in order to make plating resistance and coating resistance side by side. A composition is disclosed. When AS resin with high acrylonitrile content is used in this technology, the paint resistance of the entire rubber-reinforced styrene resin can be improved, so that suction can be reduced. The reinforced styrene resin is not suitable for injection molding because of low fluidity, and the blister phenomenon has not been solved at all.

  In Patent Document 5, in order to improve the coating resistance, components other than rubber (AS resin) in the rubber-containing graft copolymer component of the rubber-reinforced styrene resin are increased in molecular weight to 250,000 to 400,000, and the matrix component is Coating resistance was improved by using AS resin having a weight average molecular weight of 100,000 to 200,000 and acrylonitrile content of 20 to 30% and AS resin having a weight average molecular weight of less than 100,000 and acrylonitrile content of 35 to 50%. Technology is disclosed. However, with this technology, the suction can be reduced to some extent, but since a high molecular weight AS resin is used, the fluidity is insufficient, and the countermeasure for the suction at the edge portion of the injection molded product is insufficient. . In addition, the blister phenomenon has not been solved at all.

JP-A-9-302197 JP 7-267383 A JP 2005-350666 A JP 2002-256043 A JP 2000-7877 A

  The present invention provides a heat- and paint-resistant rubber-reinforced styrene-based resin composition that can obtain a good coating film appearance (no suction or blistering) even at an edge portion of an injection molded product while having high heat resistance. The issue is to provide.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have determined that rubber-reinforced styrene containing a specific graft copolymer, a heat-resistant vinyl copolymer, and a highly cyanidated vinyl copolymer. It has been found that the resin-based resin composition has both good fluidity and impact resistance while having high heat resistance, and that a good coating film appearance can be obtained even at the edge portion of the injection-molded product. .

That is, this invention is comprised by the following (1)-( 3 ).

(1) Diene rubber polymer in which two types of diene rubber polymers having a weight average particle diameter of 200 to 400 nm and 450 nm or more are blended so that the weight ratio is in the range of 9: 1 to 5: 5. (A) In the presence of 40 to 65% by weight, a vinyl monomer containing 25 to 40% by weight of an aromatic vinyl monomer (ii) and 10 to 20% by weight of a vinyl cyanide monomer (c). 15 to 50 parts by weight of graft copolymer (I) obtained by graft copolymerization of 35 to 60% by weight of the monomer mixture,
Aromatic vinyl monomer (ii) 36 to 65% by weight, vinyl cyanide monomer (c) 0 to 12% by weight and maleimide monomer (d) 35 to 52% by weight were copolymerized. 10 to 38 parts by weight of the heat-resistant vinyl copolymer (II)
Highly cyanidated vinyl copolymer (III) 5 to 60 copolymerized with aromatic vinyl monomer (ii) 60 to 70% by weight and vinyl cyanide monomer (c) 30 to 40% by weight 60 parts by weight, and vinyl-based copolymerized aromatic vinyl-based monomer (a) more than 70% by weight to 82% by weight and vinyl cyanide-based monomer (c) 18% by weight to less than 30% by weight Containing 0 to 50 parts by weight of copolymer (IV) ,
For a total of 100 parts by weight of the graft copolymer (I), the heat resistant vinyl copolymer (II), the highly cyanated vinyl copolymer (III) and the vinyl copolymer (IV), ethylene / ( A heat- and paint-resistant thermoplastic resin composition comprising 0.5 to 10 parts by weight of a (meth) acrylic acid ester / carbon monoxide copolymer (V) .

( 2 ) The heat- and paint-resistant thermoplastic resin composition according to (1 ), wherein the highly cyanidated vinyl copolymer (III) satisfies the following (A) and (B):
(A) The high vinyl cyanide copolymer (III) has an average vinyl cyanide content of 30 to 40% by weight.
(B) A copolymer having a composition higher by 2% by weight or more than the average vinyl cyanide content in the vinyl cyanide composition distribution of the highly vinyl cyanide copolymer (III) is a highly cyanidated vinyl copolymer. 20 to 50% by weight in (III).

( 3 ) A molded product formed by molding the heat-resistant and paint-resistant thermoplastic resin composition according to any one of (1) to ( 2 ).

  According to the present invention, it is possible to obtain a molded product having high heat resistance capable of forming a good coating film appearance even at the edge portion of the injection molded product by injection molding. It can correspond to the conversion.

FIG. 1 is a diagram for explaining the dimensions of a coated square plate molded product and the painted surface.

  Hereinafter, the heat-resistant and paint-resistant thermoplastic resin composition of the present invention and its molded product will be specifically described.

  The graft copolymer (I) blended in the heat-resistant / paint-resistant thermoplastic resin composition of the present invention contains an aromatic vinyl-based monomer in the presence of 40 to 65% by weight of the diene rubbery polymer (a). It is obtained by graft copolymerization of 35 to 60% by weight of a vinyl monomer mixture containing a monomer (A) and a vinyl cyanide monomer (U).

  Specific examples of the diene rubber polymer (a) include polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-butadiene block copolymer, and butyl acrylate-butadiene copolymer. Is mentioned. Of these, polybutadiene is preferably used as the diene rubbery polymer (a).

  The weight average particle diameter of the diene rubbery polymer (a) is not particularly limited, but is preferably 100 to 1500 nm, and more preferably 200 to 1200 nm. From the viewpoint of achieving both impact resistance and fluidity, it is more preferable to use two types of diene rubbery polymers (a) having a weight average particle size of 200 to 400 nm and 450 to 1200 nm in combination. In addition, when two types of weight average particle diameters of 200 to 400 nm and 450 to 1200 nm are used in combination as the diene rubbery polymer (a), those having 200 to 400 nm and those having 450 to 1200 nm are used from the viewpoint of fluidity. Is preferably in the range of 9: 1 to 5: 5, and more preferably in the range of 8: 2 to 6: 4.

  The weight average particle diameter of the diene rubber polymer (a) is determined by the sodium alginate method (sodium alginate method) described in “Rubber Age Vol. 88 p.484-490 (1960) by E. Schmidt, PH Biddison”. The particle diameter of the cumulative weight fraction of 50% is obtained from the cumulative weight fraction of the sodium alginate concentration and the cumulative weight fraction of the sodium alginate concentration.

  The diene rubbery polymer (a) preferably has a glass transition temperature of 0 ° C. or lower, and its lower limit is practically about −80 ° C.

  Although the weight fraction of the diene rubber polymer (a) in the graft copolymer (I) needs to be adjusted to 40 to 65% by weight, the weight of the preferred diene rubber polymer (a) is preferred. The fraction is 40 to 60% by weight, more preferably 40 to 50% by weight. If the weight fraction is less than 40% by weight, the impact of the material is reduced. On the other hand, if it exceeds 65% by weight, the moldability such as reduced fluidity is impaired, and the surface appearance of the molded product may be reduced. Absent.

  Examples of the aromatic vinyl monomer (a) contained in the vinyl monomer mixture include styrene, α-methyl styrene, vinyl toluene, o-ethyl styrene, p-methyl styrene, chlorostyrene, and bromostyrene. In particular, styrene is preferably used. In addition, the aromatic vinyl monomer (I) in the graft copolymer (I), the aromatic vinyl monomer (I) in the heat-resistant vinyl copolymer (II) described later, and high cyanation Even if the aromatic vinyl monomer (a) in the vinyl copolymer (III) and the aromatic vinyl monomer (a) in the vinyl copolymer (IV) are the same substance, Different materials may be used, but the same material is preferable.

  Examples of the vinyl cyanide monomer (c) contained in the vinyl monomer mixture include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, and acrylonitrile is particularly preferably used. It should be noted that the vinyl cyanide monomer (c) in the graft copolymer (I), the vinyl cyanide monomer (c) in the heat-resistant vinyl copolymer (II), and the high vinyl cyanide copolymer The vinyl cyanide monomer (c) in the polymer (III) and the vinyl cyanide monomer (c) in the vinyl copolymer (IV) were different from each other even though they were the same substance. Substances may be used, but the same substance is preferable.

  In addition, other copolymerizable monomers may be used in the vinyl monomer mixture to such an extent that the effects of the present invention are not lost. For example, N-phenylmaleimide, N-methylmaleimide, methyl methacrylate, etc. are mentioned, and can be selected according to each purpose. These can be used alone or in plural. If there is an intention to improve heat resistance and flame retardancy, N-phenylmaleimide is preferred. Further, methyl methacrylate is preferably used if importance is attached to hardness improvement and transparency.

  The total weight fraction of the vinyl-based monomer mixture needs to be adjusted to 35 to 60% by weight, and a more preferable weight fraction is 40 to 60% by weight, and particularly preferably 50 to 60% by weight. % By weight. If the total weight fraction of the vinyl-based monomer mixture is less than 35% by weight, the fluidity is lowered and the moldability may be impaired, and the surface appearance of the molded product may be lowered. On the other hand, if it exceeds 60% by weight, the impact properties of the resin composition may be lowered, which is not preferable.

  The composition ratio of the aromatic vinyl monomer (I) and the vinyl cyanide monomer (U) contained in 35 to 60% by weight of the vinyl monomer mixture is determined from the viewpoint of molding processability. The aromatic vinyl monomer (ii) is preferably in the range of 25 to 40% by weight and the vinyl cyanide monomer (c) is preferably in the range of 10 to 20% by weight, more preferably the aromatic vinyl monomer. (B) 30 to 40% by weight and vinyl cyanide monomer (c) in the range of 10 to 20% by weight.

The graft ratio of the graft copolymer (I) is preferably from 5 to 60%, more preferably from 10 to 50%, particularly preferably from 20 to 30%, from the balance between the impact ductility form and the moldability. It is. The graft ratio (%) is represented by the following formula.
Graft ratio (%) = [Amount of vinyl polymer graft-polymerized to diene rubber polymer] / [Rubber content of graft copolymer] × 100.

  The weight of the graft copolymer (I) in the heat-resistant / paint-resistant thermoplastic resin composition of the present invention is 15 to 50 parts by weight, preferably 20 to 45 parts by weight, more preferably 23 to 40 parts by weight. is there. When the amount of the graft copolymer (I) is less than 15 parts by weight, the impact resistance of the resin composition is lowered, and when it is used in excess of 50 parts by weight, the molding processability of the resin composition and the resistance to an injection molded product are reduced. Since paintability is impaired, it is not preferable.

  The heat-resistant vinyl copolymer (II) blended in the heat-resistant and paint-resistant thermoplastic resin composition of the present invention comprises 36 to 65% by weight of the aromatic vinyl monomer (ii), the vinyl cyanide single monomer. It was obtained by copolymerizing 0 to 12% by weight of the body (c) and 35 to 52% by weight of the maleimide monomer (d).

  The aromatic vinyl monomer (a) that is a constituent of the heat-resistant vinyl copolymer (II) is the same as the aromatic vinyl monomer (a) in the graft copolymer (I) described above. Examples thereof include styrene, α-methylstyrene, vinyltoluene, o-ethylstyrene, p-methylstyrene, chlorostyrene, bromostyrene and the like. These are not necessarily used alone, and can be used in combination of two or more. Of these, styrene is particularly preferably employed.

  The vinyl cyanide monomer (c), which is a component of the heat resistant vinyl copolymer (II), is the same as the vinyl cyanide monomer (c) in the graft copolymer (I) described above. Examples thereof include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like. These are not necessarily used alone, and can be used in combination of two or more. Of these, acrylonitrile is particularly preferably employed.

  Examples of the maleimide monomer (d) that is a constituent of the heat-resistant vinyl copolymer (II) include N-phenylmaleimide, N-methylmaleimide, and N-cyclohexylmaleimide, and preferably N-phenylmaleimide is used. Can be mentioned.

  The monomer composition ratio constituting the heat-resistant vinyl copolymer (II) is 36 to 65% by weight of the aromatic vinyl monomer (ii), 0 to 12% by weight of the vinyl cyanide monomer (c). , Maleimide monomer (d) in the range of 35 to 52% by weight, preferably 37 to 50% by weight. In particular, if the addition amount of the maleimide monomer is less than 35% by weight, the effect of improving the heat resistance of the resin composition is small, and if it exceeds 52% by weight, the moldability of the resin composition may be impaired.

  The reduced viscosity of the heat-resistant vinyl copolymer (II) measured with an Ubbelohde viscometer of a dimethyl sulfoxide solution at 30 ° C. and 0.4 g / dl is preferably 0.3 to 0.7 dl / g, More preferably, it is 0.4 to 0.6 dl / g. When the reduced viscosity of the heat-resistant vinyl copolymer (II) is less than 0.3 dl / g, the impact resistance of the resin composition may be lowered, whereas when it exceeds 0.7 dl / g. In some cases, the fluidity of the resin composition is lowered, making it difficult to mold a large molded article.

  The weight of the heat-resistant vinyl copolymer (II) in the heat-resistant / paint-resistant thermoplastic resin composition of the present invention is 10 to 38 parts by weight, preferably 12 to 36 parts by weight, more preferably 15 to 35 parts by weight. Part. When the heat-resistant vinyl copolymer (II) is less than 10 parts by weight, the resin composition of the present invention does not reach the target heat resistance level (heat distortion temperature of 85 ° C. or higher), while it exceeds 38 parts by weight. When used, the heat resistance is increased, but not only the impact resistance is lowered, but also the fluidity is greatly lowered, and the coating resistance of the injection molded product (suction phenomenon, edge blister phenomenon) is also preferred. Absent.

  The highly cyanidated vinyl copolymer (III) blended in the heat-resistant and paint-resistant thermoplastic resin composition of the present invention comprises an aromatic vinyl-based monomer (ii) 60 to 70% by weight, a vinyl cyanide-based copolymer. It is obtained by copolymerizing 30 to 40% by weight of the monomer (c).

  The aromatic vinyl monomer (I), which is a constituent component of the highly cyanidated vinyl copolymer (III), is a fragrance produced by the graft copolymer (I) and the heat-resistant vinyl copolymer (II). Similar to the group vinyl monomer (A), styrene, α-methylstyrene, vinyltoluene, o-ethylstyrene, p-methylstyrene, chlorostyrene, bromostyrene and the like can be mentioned. These are not necessarily used alone, and can be used in combination of two or more. Of these, styrene is particularly preferably employed.

  As the vinyl cyanide monomer (c), which is a constituent of the high vinyl cyanide copolymer (III), the above-mentioned graft copolymer (I) and heat-resistant vinyl copolymer (II) Examples of the vinyl cyanide monomer (c) include acrylonitrile, methacrylonitrile and ethacrylonitrile. These are not necessarily used alone, and can be used in combination of two or more. Of these, acrylonitrile is particularly preferably employed.

  If the vinyl cyanide monomer in the high vinyl cyanide copolymer (III) is less than 30% by weight, the chemical resistance of the resin composition as a whole tends to deteriorate and coating defects (suction) tend to occur. On the other hand, if it exceeds 40% by weight, it is difficult to increase the degree of polymerization of the highly vinyl cyanide copolymer (III), and the impact resistance of the entire resin composition is lowered. This is not preferable because it may occur.

  The intrinsic viscosity derived from the Ubbelohde viscosity measurement of a methyl ethyl ketone solution at 30 ° C. and 0.2, 0.4 g / dl of the high vinyl cyanide copolymer (III) is 0.3 to 0.7 dl / g. It is preferably 0.3 to 0.6 dl / g. When the reduced viscosity of the highly vinyl cyanide copolymer (III) is less than 0.3 dl / g, the impact resistance of the resin composition may be lowered, whereas when the reduced viscosity exceeds 0.7 dl / g In some cases, the fluidity of the resin composition is lowered, making it difficult to mold a large molded product.

  The weight of the highly cyanidated vinyl copolymer (III) in the heat resistant / paint resistant thermoplastic resin composition of the present invention is in the range of 5 to 60 parts by weight, preferably 8 to 58 parts by weight, more preferably. 9 to 56 parts by weight. When the amount of the high vinyl cyanide copolymer (III) is less than 5 parts by weight, the coating resistance (suction phenomenon, blister phenomenon of the edge part) of the injection molded product is deteriorated, while it exceeds 60 parts by weight. If used, the impact resistance of the resin is lowered, which is not preferable.

It is preferable that the highly cyanidated vinyl copolymer (III) blended in the heat-resistant and paint-resistant thermoplastic resin composition of the present invention satisfies the following characteristics (A) and (B).
(A) The high vinyl cyanide copolymer (III) has an average vinyl cyanide content of 30 to 40% by weight.
(B) A copolymer having a composition higher by 2% by weight or more than the average vinyl cyanide content in the vinyl cyanide composition distribution of the highly vinyl cyanide copolymer (III) is a highly cyanidated vinyl copolymer. 20 to 50% by weight in (III).

  When the average vinyl cyanide content of the high vinyl cyanide copolymer (III) is less than 30% by weight, the coating resistance (improvement of suction and blistering) at the edge of the injection molded product may not be sufficient. On the other hand, if it exceeds 40% by weight, the color stability at the time of melting may decrease. The average vinyl cyanide content of the highly vinyl cyanide copolymer (III) is more preferably 31 to 37% by weight from the viewpoint of the balance between the coating resistance and the color stability at the time of melting.

  Similarly, in the composition distribution of the vinyl cyanide monomer of the highly cyanidated vinyl copolymer (III), a copolymer having a composition higher by 2% by weight or more than the average vinyl cyanide content is a highly cyanidated vinyl copolymer. When the ratio contained in the copolymer (III) is less than 20% by weight, the coating resistance of the resulting coating-resistant thermoplastic resin composition may not be sufficient, while when it exceeds 50% by weight, Color stability may be reduced. In terms of the balance between paint resistance and stability of color tone when melted, the composition distribution of the vinyl cyanide monomer of the highly vinyl cyanide copolymer (III) is 2% by weight from the average vinyl cyanide content. More preferably, the copolymer having a composition higher by at least 25% is present in the highly vinyl cyanide copolymer (III) in an amount of 25 to 45% by weight, more preferably 25 to 40% by weight.

  The composition distribution of vinyl cyanide in the highly vinyl cyanide copolymer (III) was determined by adding cyclohexane to the methyl ethyl ketone solution of the highly cyanidated vinyl copolymer (III), followed by fractional precipitation. After the polymer is dried and weighed, it is obtained by determining the vinyl cyanide content with an infrared spectrophotometer. The average vinyl cyanide content can be obtained by determining the vinyl cyanide content with an infrared spectrophotometer without fractionation.

  The heat-resistant / paint-resistant thermoplastic resin composition of the present invention can be formed by a graft copolymer (I), a heat-resistant vinyl copolymer (II), and a highly cyanidated vinyl copolymer (III). Vinyl copolymer (IV) can be used in the range of 50 parts by weight or less, preferably 0 to 45 parts by weight, more preferably 0 to 40 parts by weight, in view of the balance between the property and impact property. The If the vinyl copolymer (IV) is used in an amount exceeding 50 parts by weight, the chemical resistance of the resin composition is lowered, and the coating resistance of the injection molded product is lowered (suction phenomenon, edge blister phenomenon). There are things to do.

  The aromatic vinyl monomer (I), which is a constituent of the vinyl copolymer (IV), is prepared by using the graft copolymer (I), the heat-resistant vinyl copolymer (II), and the high cyanide vinyl copolymer. Similar to the aromatic vinyl monomer (a) in the polymer (III), styrene, α-methylstyrene, vinyltoluene, o-ethylstyrene, p-methylstyrene, chlorostyrene, bromostyrene and the like can be mentioned. . These are not necessarily used alone, and can be used in combination of two or more. Of these, styrene is particularly preferably employed.

  Examples of the vinyl cyanide monomer (c) that is a component of the vinyl copolymer (IV) include the graft copolymer (I), the heat-resistant vinyl copolymer (II), and the high vinyl cyanide. Examples of the vinyl cyanide monomer (c) in the copolymer (III) include acrylonitrile, methacrylonitrile and ethacrylonitrile. These are not necessarily used alone, and can be used in combination of two or more. Of these, acrylonitrile is particularly preferably employed.

  In addition to the aromatic vinyl monomer (a) and the vinyl cyanide monomer (c), the vinyl copolymer (IV) includes other copolymerizable monomers. Polymerization may be performed. Examples of other copolymerizable monomers include N-phenylmaleimide, N-methylmaleimide, and methyl methacrylate. These are not necessarily used alone, and a plurality of them can be used. is there.

  The monomer composition ratio constituting the vinyl copolymer (IV) is more than 70% by weight to 82% by weight of the aromatic vinyl monomer (ii), and 18% by weight of the vinyl cyanide monomer (c). It is in the range of ˜30 wt%, preferably 19 wt% or more and less than 30 wt%, more preferably 20 wt% or more and less than 30 wt%. When the vinyl cyanide monomer of the vinyl copolymer (IV) is less than 18% by weight, the chemical resistance of the entire resin composition is lowered, and the coating resistance (suction phenomenon, The blister phenomenon at the edge portion) may be lowered, which is not preferable.

  It is preferable that the intrinsic viscosity derived from the Ubbelohde viscosity measurement of a methyl ethyl ketone solution at 30 ° C. and 0.2, 0.4 g / dL of the vinyl copolymer (IV) is preferably 0.3 to 0.8 dl / g. More preferably, it is 0.3 to 0.6 dl / g. When the intrinsic viscosity of the vinyl copolymer (IV) is less than 0.3 dl / g, the impact resistance of the resin composition may be lowered, whereas when it exceeds 0.8 dl / g In addition, the fluidity of the resin composition may be reduced, and it may be difficult to mold a large molded product.

  In the present invention, there are no particular restrictions on the method for producing the graft copolymer (I), the heat-resistant vinyl copolymer (II), the highly cyanated vinyl copolymer (III) and the vinyl copolymer (IV). Instead, bulk polymerization, suspension polymerization, bulk suspension polymerization, solution polymerization, emulsion polymerization, precipitation polymerization, and combinations thereof are used. There is no particular limitation on the monomer charging method, and it may be added all at once in the initial stage, or the addition method may be divided into several times in order to impart or prevent the composition distribution of the copolymer. .

  In the present invention, the initiator used for the polymerization of the graft copolymer (I), the heat resistant vinyl copolymer (II), the highly cyanidated vinyl copolymer (III), and the vinyl copolymer (IV). As such, a peroxide or an azo compound is preferably used.

  Specific examples of the peroxide include, for example, benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, t-butyl cumyl peroxide, and t-butyl peroxide. Acetate, t-butyl peroxybenzoate, t-butyl peroxyisopropyl carbonate, di-t-butyl peroxide, t-butyl peroctate, 1,1-bis (t-butylperoxy) 3, 3, 5 -Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, t-butylperoxy-2-ethylhexanoate and the like. Of these, cumene hydroperoxide and 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane are particularly preferably used.

  Specific examples of the azo compound include azobisisobutyronitrile, azobis (2,4dimethylvaleronitrile), 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2-cyano- 2-propylazoformamide, 1,1'-azobiscyclohexane-1-carbonitrile, azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, 1-t -Butylazo-1-cyanocyclohexane, 2-t-butylazo-2-cyanobutane, 2-t-butylazo-2-cyano-4-methoxy-4-methylpentane, and the like. Of these, azobisisobutyronitrile is particularly preferably used.

  When using these initiators, they are used alone or in combination of two or more.

  The purpose of polymerization is to control the degree of polymerization of graft copolymer (I), heat-resistant vinyl copolymer (II), highly cyanidated vinyl copolymer (III), and vinyl copolymer (IV). It is also possible to use chain transfer agents such as mercaptans and terpenes. Specific examples of the chain transfer agent include n-octyl mercaptan, t-dodecyl mercaptan, n-dodecyl mercaptan, n-tetradecyl mercaptan, n-octadecyl mercaptan and terpinolene. Of these, n-octyl mercaptan, t-dodecyl mercaptan and n-dodecyl mercaptan are preferably used. When using these chain transfer agents, they are used alone or in combination of two or more.

  In addition, regarding the highly cyanidated vinyl copolymer (III) used in the resin composition of the present invention, a production method for satisfying the above-mentioned features (A) and (B) is, for example, Japanese Patent No. 3141707. And an aqueous suspension polymerization method disclosed in Japanese Patent Publication No.

  Addition of ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V) to the heat-resistant / paint-resistant thermoplastic resin composition of the present invention is also one preferred embodiment. By adding the ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V), the blistering phenomenon of the coated product can be further suppressed.

  The ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V) is a copolymer characterized by containing at least ethylene, (meth) acrylic acid ester and carbon monoxide as monomer components. It may be a random copolymer or a block copolymer, but is preferably a block copolymer. Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, and (meth) acrylic sec. -Butyl, t-butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, and the like are preferable. (Meth) methyl acrylate, (meth) ethyl acrylate, (meth) acrylate n-propyl, (meth) acrylate n-butyl, (meth) acrylate sec-butyl, (meth) acrylate t-butyl, ( (Meth) isobutyl acrylate.

  Each composition ratio of ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (IV) is preferably 10 to 85% by weight of ethylene, more preferably 40 to 80% by weight, and (meth) acrylic acid ester Preferably it is 10 to 50% by weight, more preferably 15 to 40% by weight, carbon monoxide is preferably 5 to 40% by weight, more preferably 5 to 20% by weight, and other copolymerization is possible if necessary. It can also be copolymerized with various monomers.

  The addition amount of ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V) is as follows: graft copolymer (I), heat-resistant vinyl copolymer (II), highly cyanidated vinyl copolymer ( Preferably it is 0.5-10 weight part with respect to a total of 100 weight part of III) and vinyl type copolymer (IV), More preferably, it is 1-7 weight part. By making the addition amount of ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V) in the range of 0.5 to 10 parts by weight, heat resistance and coating resistance can be expressed in a balanced manner. it can.

  In addition, different resins can be blended and used in the resin composition of the present invention as long as the characteristics of the present invention are not impaired. For example, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, polycyclohexylene dimethylene ethylene terephthalate, polyarylate, liquid crystal polymer, polylactic acid, polyester resin represented by polycaprolactone, nylon 6, nylon 6,6, nylon 6,10 Polyamide resin such as nylon 4,6, nylon 6T, nylon 9T, nylon 11, etc., PPS resin, polyacetal resin, crystalline styrene resin, PPE resin, etc. can be used according to the purpose.

  Furthermore, a known impact resistance improving material can be used as long as the characteristics of the present invention are not impaired. Examples of impact resistance improvers that can be used include natural rubber, polyethylene such as low density polyethylene and high density polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / methyl acrylate copolymer, and ethylene / ethyl acrylate copolymer. , Ethylene / vinyl acetate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / butyl acrylate copolymer, ethylene / ethyl acrylate / carbon monoxide copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / methyl acrylate / Glycidyl methacrylate copolymers, ethylene / butyl acrylate / glycidyl methacrylate copolymers, ethylene / octene-1 copolymers, ethylene elastomers such as ethylene / butene-1 copolymers, polyethylene Examples include polyester elastomers such as phthalate / poly (tetramethylene oxide) glycol block copolymers, polyethylene terephthalate / isophthalate / poly (tetramethylene oxide) glycol block copolymers, MBS or acrylic core-shell elastomers, and styrene elastomers. The These are not necessarily used alone, and two or more kinds can be used in combination.

  Furthermore, it is possible to add an inorganic filler as long as the characteristics of the present invention are not impaired. As the kind of inorganic filler, glass fiber can be preferably used. In addition, the shape of the inorganic filler may be any shape such as a fiber shape, a plate shape, a powder shape, and a granular shape. Specifically, PAN-based and pitch-based carbon fibers, stainless steel fibers, metal fibers such as aluminum fibers and brass fibers, organic fibers such as aromatic polyamide fibers, gypsum fibers, ceramic fibers, asbestos fibers, zirconia fibers, alumina fibers Fiber, whisker-like filler, mica, talc, silica fiber, titanium oxide fiber, silicon carbide fiber, glass fiber, rock wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, etc. Kaolin, silica, calcium carbonate, glass flakes, glass beads, glass microballoons, clay, molybdenum disulfide, wollastonite, montmorillonite, titanium oxide, zinc oxide, barium sulfate, calcium polyphosphate, graphite, etc. Or plate-like fillers. In particular, the type of glass fiber is not particularly limited as long as it is generally used for reinforcing a resin, and can be selected from, for example, a long fiber type, a short fiber type chopped strand, a milled fiber, or the like. In addition, the said inorganic filler can also be used by processing the surface with a well-known coupling agent (For example, a silane coupling agent, a titanate coupling agent, etc.) and another surface treating agent. The glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer, or a thermosetting resin such as an epoxy resin. The inorganic filler may be coated or focused with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin, or treated with a coupling agent such as aminosilane or epoxysilane. May be.

  The resin composition of the present invention includes, as necessary, a hindered phenol-based antioxidant, a sulfur-containing compound-based antioxidant, a phosphorus-containing organic compound-based antioxidant, a phenol-based, an acrylate-based thermal antioxidant, Flame retardants such as benzotriazole, benzophenone and succinate UV absorbers, decabromobiphenyl ether, tetrabromobisphenol A, chlorinated polyethylene, brominated epoxy oligomer, brominated polycarbonate, antimony trioxide, condensed phosphate -Flame retardant aids, antibacterial agents typified by silver antibacterial agents, antifungal agents, carbon black, titanium oxide, mold release agents, lubricants, pigments and dyes can also be added.

  The resin composition of the present invention can be obtained by melting and mixing constituent copolymer components. Although there is no restriction | limiting in particular regarding the melt mixing method, The method of melt-mixing using a monoaxial or biaxial screw with a heating apparatus and the cylinder which has a vent is employable. The heating temperature at the time of melt mixing is usually selected from the range of 210 to 320 ° C. However, it is also possible to freely set the temperature gradient at the time of melt mixing within a range that does not impair the object of the present invention. Further, when a biaxial screw is used, it may be in the same rotational direction or in a different rotational direction.

  The method for molding the resin composition of the present invention is not particularly limited, but it is suitably molded by injection molding. The injection molding can be carried out in the temperature range for normal molding, preferably 220 to 300 ° C. Moreover, the mold temperature at the time of injection molding is preferably a temperature range used for normal molding at 30 to 80 ° C.

  The resin composition of the present invention has fluidity and impact resistance suitable for molding into a large molded product despite having heat resistance of 85 ° C. or higher with an ISO 1.8 MPa heat distortion temperature. Even if it is applied to an injection-molded product having an edge of less than 90 °, it is characterized in that a painted part free from defective painting such as suction or blistering can be obtained. Moreover, since the resin composition of the present invention has good moldability, it is suitable for a large or complicated molded product. That is, the resin composition of the present invention is suitable for a power window panel, a center console, a center cluster, a lever controller, a console box, and the like for painted parts for an automobile interior such as a rear spoiler, a wheel cap, a door mirror, and a radiator grill of an automobile exterior. In addition, it can be suitably used for electrical and electronic applications and residential / building material applications.

  In order to describe the present invention more specifically, examples are given below, but these examples do not limit the present invention in any way.

  A method for analyzing the resin characteristics of the thermoplastic resin composition will be described below.

(1) Graft rate 200 ml of acetone was added to a predetermined amount (m; about 1 g) of the graft copolymer and refluxed in a hot water bath at a temperature of 70 ° C. for 3 hours. p. m. After centrifuging at (10000 G) for 40 minutes, the insoluble matter was filtered, this insoluble matter was dried under reduced pressure at a temperature of 60 ° C. for 5 hours, and the weight (n) was measured. The graft ratio was calculated from the following formula. Here, L is the rubber content of the graft copolymer.
Graft rate (%) = {[(n) − (m) × L] / [(m) × L]} × 100.

(2) Reduced viscosity The reduced viscosity of the heat-resistant vinyl copolymer (II) was measured using a Ubbelohde viscometer from a dimethyl sulfoxide solution having a measurement temperature of 30 ° C and a sample concentration of 0.4 g / dl.

(3) Intrinsic viscosity The intrinsic viscosity of the highly cyanidated vinyl copolymer (III) and vinyl copolymer (IV) was measured using an Ubbelohde viscometer at a measurement temperature of 30 ° C., a sample concentration of 0.2 g,. The intrinsic viscosity was derived from a 4 g / dl methyl ethyl ketone solution.

(4) Average vinyl cyanide content The high vinyl cyanide copolymer (III) and the vinyl copolymer (IV) were formed into a film of about 40 μm by a heating press and determined by an infrared spectrophotometer.

(5) Vinyl cyanide composition distribution 2 g of each sample of the highly vinyl cyanide copolymer (III) and vinyl copolymer (IV) was dissolved in 80 ml of methyl ethyl ketone, and cyclohexane was added thereto to precipitate. The vinyl cyanide copolymer thus obtained was vacuum-dried and weighed, and the vinyl cyanide content of the vinyl cyanide copolymer was determined from the absorbance ratio of infrared spectroscopic analysis. Then, the cumulative weight% and vinyl cyanide content were plotted, and a ratio (%) of 2% by weight or more was determined from the average vinyl cyanide content.

(6) Heat resistance Thermal deformation temperature: Measured according to ISO75-2 (measured under 1.8 MPa conditions).

(7) Impact property Charpy impact strength: measured in accordance with ISO 179 (notched).

(8) Fluidity Melt flow rate: Measured according to ISO 1133 (measured at a temperature of 240 ° C. and a 98N load condition).

(9) Paint surface appearance of molded product with edge The paintability evaluation test of the molded product was evaluated as follows. Using an injection molding machine, set the cylinder temperature to 250 ° C, mold temperature to 40 ° C and 60 ° C, and set the 70 × 240 × 2mmt square plate (edge in the longitudinal direction, edge angle 45 °, 60 °). Molded (FIG. 1). After coating the square plate with an acrylic-urethane two-component paint (urethane PG60 / hardener, manufactured by Kansai Paint Co., Ltd., painting robot: KE610H manufactured by Kawasaki Heavy Industries, Ltd., cartridge cartridge manufactured by ABB, with a coating thickness of 30 μm. And dried for 30 minutes at a drying temperature of 80 ° C. Visibility and appearance of the obtained coated molded product were visually determined according to the following criteria: ◎ and ○ were acceptable levels, and △ and × were unacceptable levels. did.
A: A high gloss feeling is confirmed.
○: Glossy but not highly glossy.
Δ: Some coating unevenness is present in part.
X: The coating unevenness is conspicuous as a whole. There is a problem.

(10) Blister evaluation About the blister formed in the edge part of the coating molded product of (9), it evaluated by the total quantity of each 10 test pieces.

Reference Example 1 [Production of Graft Copolymer (I)]
Preparation of graft copolymer (I-1) In the presence of 60% by weight (in terms of solid content) of polybutadiene latex (weight average particle diameter 350 nm), a monomer mixture consisting of 29% by weight of styrene and 11% by weight of acrylonitrile Emulsion polymerization was performed using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to give the graft copolymer (I-1). Prepared. The graft rate was 36%.

Preparation of graft copolymer (I-2) In the presence of 45% by weight (in terms of solid content) of polybutadiene latex (weight average particle diameter 350 nm), a monomer mixture comprising 40% by weight of styrene and 15% by weight of acrylonitrile Emulsion polymerization was performed using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with a sodium hydroxide aqueous solution, then washed, dehydrated and dried to obtain a graft copolymer (I- 2 ). Prepared. The graft rate was 42%.

-Preparation of graft copolymer (I-3) Polybutadiene latex (in combination of two weight average particle sizes of 350 nm and 800 nm, ratio 8: 2) in the presence of 45% by weight (in terms of solid content), 40% by weight of styrene A monomer mixture consisting of 15% by weight of acrylonitrile was emulsion-polymerized using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to obtain a graft copolymer (I-3). Prepared. The graft rate was 25%.

Graft copolymer (I-4) Preparation of polybutadiene latex (combination weight average Hitoshitsubu element diameter 350nm and 800 nm 2 kinds of ratio 6: 4) in the presence of 45 wt% (in terms of solid content), styrene 40 A monomer mixture consisting of 15% by weight and 15% by weight of acrylonitrile was emulsion-polymerized using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to give the graft copolymer (I-4). Prepared. The graft rate was 22%.

-Preparation of graft copolymer (I-5) In the presence of 70% by weight (in terms of solid content) of polybutadiene latex (weight average particle diameter 350 nm), a monomer mixture consisting of 21% by weight of styrene and 9% by weight of acrylonitrile Emulsion polymerization was performed using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to obtain a graft copolymer (I-5). Prepared. The graft rate was 34%.

Preparation of graft copolymer (I-6) In the presence of 35% by weight of polybutadiene latex (weight average particle diameter 350 nm) (in terms of solid content), a monomer mixture consisting of 48% by weight of styrene and 17% by weight of acrylonitrile was prepared. Emulsion polymerization was performed using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to obtain a graft copolymer (I-6). Prepared. The graft rate was 25%.

Preparation of graft copolymer (I-7) In the presence of 60% by weight (in terms of solid content) of polybutadiene latex (weight average particle size 350 nm), a monomer mixture comprising 34% by weight of styrene and 6% by weight of acrylonitrile was prepared. Emulsion polymerization was performed using potassium stearate to obtain a rubber-reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to obtain a graft copolymer (I-7). Prepared. The graft rate was 42%.

Graft copolymer in the presence of (I-8) Preparation of polybutadiene latex (weight average Hitoshitsubu child size 350 nm) 60 wt% (solid basis), of styrene 18 wt% of acrylonitrile 22 wt% monomer The mixture was emulsion polymerized using potassium stearate to obtain a rubber reinforced styrene resin latex. This was added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., aggregated, neutralized with an aqueous sodium hydroxide solution, then washed, dehydrated and dried to obtain a graft copolymer ( I- 8). Prepared. The graft rate was 5%.

(Reference Example 2) [Production of heat-resistant vinyl copolymer (II)]
-Preparation of heat-resistant vinyl copolymer (II-1) Emulsion polymerization was performed using potassium stearate from a monomer mixture consisting of 37% by weight of N-phenylmaleimide, 54% by weight of styrene and 9% by weight of acrylonitrile. After adding and aggregating in a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., neutralizing with a sodium hydroxide aqueous solution, and then washing, dehydrating and drying steps, the heat-resistant vinyl copolymer (II-1) is obtained. Prepared. The reduced viscosity (ηsp / c) of the obtained heat-resistant vinyl copolymer (II-1) was 0.55 dl / g.

-Preparation of heat-resistant vinyl copolymer (II-2) Emulsion polymerization was performed using potassium stearate from a monomer mixture consisting of 40% by weight of N-phenylmaleimide, 50% by weight of styrene and 10% by weight of acrylonitrile. , Added to a 0.3% dilute sulfuric acid aqueous solution at a temperature of 90 ° C., agglomerated, neutralized with an aqueous sodium hydroxide solution, and then washed, dehydrated and dried to obtain a heat-resistant vinyl copolymer (II-2). Prepared. The reduced viscosity (ηsp / c) of the obtained heat-resistant vinyl copolymer (II-2) was 0.53 dl / g.

-Preparation of heat-resistant vinyl copolymer (II-3) From a monomer mixture consisting of 50% by weight of N-phenylmaleimide and 50% by weight of styrene, emulsion polymerization is performed using potassium stearate, and the temperature is 90 ° C. After adding and aggregating in a 0.3% dilute sulfuric acid aqueous solution, the solution was neutralized with a sodium hydroxide aqueous solution and then subjected to washing, dehydration and drying steps to prepare a heat-resistant vinyl copolymer (II-3). The reduced viscosity (ηsp / c) of the obtained heat-resistant vinyl copolymer (II- 3 ) was 0.46 dl / g.

(Reference Example 3) [Production of High Cyanide Copolymer (III)]
-Preparation of highly vinyl cyanide copolymer (III-1) In a stainless steel autoclave having a capacity of 20 liters and equipped with a baffle and a foudra-type stirring blade, 0.05 part by weight of a methyl methacrylate / acrylamide copolymer ( A solution prepared by dissolving JP-B-45-24151 in 165 parts by weight of ion-exchanged water was stirred at 400 rpm, and the system was replaced with nitrogen gas. Then 30 parts by weight acrylonitrile, 12 parts by weight styrene, 0.46 parts by weight t-dodecyl mercaptan, 0.39 parts by weight 2,2′-azobis (2,4-dimethylvaleronitrile), 0.05 A mixed solution of 2,2′-azobisisobutylnitrile in parts by weight was added while stirring the reaction system, and the copolymerization reaction was started at 58 ° C. After 15 minutes from the start of polymerization, 58 parts by weight of styrene was intermittently added over 110 minutes from a supply pump provided at the top of the autoclave. During this time, the reaction temperature was raised to 58 to 65 ° C. at the start of polymerization. After the intermittent addition of styrene to the reaction system was completed, the temperature was raised to 100 ° C. over 50 minutes. The slurry obtained by cooling was subjected to washing, dehydration and drying steps to prepare a highly cyanidated vinyl copolymer (III-1). The intrinsic vinyl cyanide copolymer (III-1) obtained had an intrinsic viscosity of 0.53 dl / g. Further, the average vinyl cyanide content was 31% by weight, and the ratio of 2% by weight or more from the average vinyl cyanide content was 26%.

-Preparation of highly vinyl cyanide copolymer (III-2) 0.05 parts by weight of methyl methacrylate / acrylamide copolymer (into a stainless steel autoclave having a capacity of 20 liters and baffle and foudra type stirring blades ( A solution prepared by dissolving JP-B-45-24151 in 165 parts by weight of ion-exchanged water was stirred at 400 rpm, and the system was replaced with nitrogen gas. Then 38 parts by weight acrylonitrile, 4 parts by weight styrene, 0.46 parts by weight t-dodecyl mercaptan, 0.39 parts by weight 2,2'-azobis (2,4-dimethylvaleronitrile), 0.05 A mixed solution of 2,2′-azobisisobutylnitrile in parts by weight was added while stirring the reaction system, and the copolymerization reaction was started at 58 ° C. After 15 minutes from the start of polymerization, 58 parts of styrene were intermittently added over 110 minutes from a supply pump provided at the top of the autoclave. During this time, the reaction temperature was raised to 58 to 65 ° C. at the start of polymerization. After the intermittent addition of styrene to the reaction system was completed, the temperature was raised to 100 ° C. over 50 minutes. The slurry obtained by cooling was subjected to washing, dehydration and drying steps to prepare a highly cyanidated vinyl copolymer (III-2). The intrinsic vinyl cyanide copolymer (III-2) obtained had an intrinsic viscosity of 0.45 dl / g. The average vinyl cyanide content was 38% by weight, and the ratio of 2% by weight or more from the average vinyl cyanide content was 40% by weight.

-Preparation of highly vinyl cyanide copolymer (III-3) In a stainless steel autoclave having a capacity of 20 liters and equipped with a baffle and a fowler type stirring blade, 0.05 part by weight of a methyl methacrylate / acrylamide copolymer ( A solution prepared by dissolving JP-B-45-24151 in 165 parts by weight of ion-exchanged water was stirred at 400 rpm, and the system was replaced with nitrogen gas. Then 42 parts by weight acrylonitrile, 4 parts by weight styrene, 0.46 parts by weight t-dodecyl mercaptan, 0.39 parts by weight 2,2'-azobis (2,4-dimethylvaleronitrile), 0.05 A mixed solution of 2,2′-azobisisobutylnitrile in parts by weight was added while stirring the reaction system, and the copolymerization reaction was started at 58 ° C. After 15 minutes from the start of polymerization, 54 parts by weight of styrene was intermittently added over 110 minutes from a supply pump provided at the top of the autoclave. During this time, the reaction temperature was raised to 58 to 65 ° C. at the start of polymerization. After the intermittent addition of styrene to the reaction system was completed, the temperature was raised to 100 ° C. over 50 minutes. The slurry obtained by cooling was subjected to washing, dehydration and drying steps to prepare a highly cyanidated vinyl copolymer (III-3). The intrinsic vinyl cyanide copolymer (III-3) obtained had an intrinsic viscosity of 0.35 dl / g. The average vinyl cyanide content was 45% by weight, and the ratio of 2% by weight or more from the average vinyl cyanide content was 45%.

Reference Example 4 [Production of Vinyl Copolymer (IV)]
-Preparation of vinyl copolymer (IV-1) Using a continuous bulk polymerization apparatus consisting of a preheater and a demonomer, a monomer mixture consisting of 72% by weight of styrene and 28% by weight of acrylonitrile was continuously bulked at 135 kg / hour. Polymerized. In the polymerization reaction mixture, unreacted monomers were collected by evaporation under reduced pressure from a vent port using a single screw extruder type demonomer, while vinyl copolymer (IV-1) was obtained from the demonomer. The intrinsic viscosity of the obtained vinyl copolymer (IV-1) was 0.54 dl / g. The average vinyl cyanide content was 26% by weight, and the ratio of 2% by weight or more from the average vinyl cyanide content was 0% by weight.

-Preparation of vinyl copolymer (IV-2) A slurry obtained by suspension polymerization of a monomer mixture consisting of 76% by weight of styrene and 24% by weight of acrylonitrile was subjected to washing, dehydration and drying steps to obtain a vinyl-based copolymer. Copolymer (IV-2) was prepared. The intrinsic viscosity of the obtained vinyl copolymer (IV-2) was 0.42 dl / g. The average vinyl cyanide content was 25% by weight, and the ratio of 2% by weight or more from the average vinyl cyanide content was 18% by weight.

Reference Example 5 Ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V)
・ Ethylene / ethyl acrylate / carbon monoxide block copolymer (V-1)
“Elvalloy” EP4051 manufactured by Mitsui DuPont Polychemicals.

・ Ethylene / ethyl acrylate / carbon monoxide block copolymer (V-2)
“Elvalloy” HP553 manufactured by Mitsui DuPont Polychemicals.

(Ratio Comparative Examples 1 to 14, Reference Example 3 to 16)
Graft copolymer (I), heat-resistant vinyl copolymer (II), highly cyanidated vinyl copolymer (III), vinyl copolymer (IV) and ethylene / (meth) acrylic described in Reference Examples After blending the acid ester / carbon monoxide copolymer (V) in the ratios shown in Tables 1 and 2, it was melted in a twin screw extruder (temperature range: 240 to 250 ° C.) rotating in the same direction with a screw diameter of 30 mm. Kneading was performed to obtain pellets. Test pieces were prepared with a molding machine (molding temperature 250 ° C., mold temperature 60 ° C.) so that the obtained pellets were suitable for each physical property evaluation, and the evaluation was performed. However, test specimens for coating evaluation were prepared under the conditions described in (9) Painted surface appearance of molded article with edge and (10) Blister evaluation. Table 1 shows the results of the reference examples, and Tables 1 and 2 show the results of the comparative examples.

  As a result, the following became clear.

1. From the comparison between Reference Examples 1 to 4 and Comparative Examples 3 and 4, it was found that when a diene rubber polymer in the graft copolymer component (I) was used in an amount less than the specified amount, the resin composition On the other hand, when the impact resistance of the object was reduced, when the amount was more than the specified amount, the fluidity was lowered, and accordingly, the gloss at the time of coating was lowered.

2. From comparison between Reference Examples 3, 5 to 8 and Comparative Examples 1, 2 and 12, when the graft copolymer component (I) is less than the specified amount, the impact resistance is lowered, while the graft copolymer component is When the amount was larger than the specified amount, the fluidity of the resin composition was lowered, and the gloss at the time of coating was lowered accordingly.

3. From the comparison between Reference Examples 3, 9, and 10 and Comparative Examples 7, 8, and 11, if the amount of the heat-resistant vinyl copolymer (II) is less than the specified amount, there is no problem in the paintability, but the heat resistance is lowered. On the other hand, when the amount exceeds the specified amount, the heat resistance becomes high, but the impact strength and fluidity are greatly reduced, and the gloss at the time of painting is also lowered.

4). From the comparison between Reference Examples 3, 9 to 14 and Comparative Examples 7, 9, and 10, the coating property deteriorates when the addition amount of the highly cyanidated vinyl copolymer (III) is less than the specified amount, and the amount exceeds the specified amount. When the amount is too large, heat resistance cannot be obtained.

5. From the comparison between Reference Examples 1 to 4 and Comparative Examples 5 and 6, when the amount of acrylonitrile added in the graft copolymer component (I) is larger than the specified amount, the impact resistance of the resin composition On the other hand, when the amount is less than the specified amount, the fluidity is lowered and the blisters at the edge portion are further increased.

6). From comparison between Reference Examples 11 to 14 and Comparative Examples 11 and 12, when the added amount of the vinyl copolymer (IV) was larger than the specified amount, blisters at the edge portion increased.

7). From a comparison between Reference Examples 15 and 16 and Reference Examples 1 to 12, blisters were further reduced by adding a specified amount of ethylene / (meth) acrylic acid ester / carbon monoxide copolymer (V).

  The heat-resistant and paint-resistant thermoplastic resin composition of the present invention is used for automobile interior paint parts such as rear spoilers, wheel caps, door mirrors, and radiator grilles, and for interior parts such as power wind panels, center consoles, and center clusters. It can be suitably used for a lever controller, a console box, etc., and can be used for other electrical / electronic applications and residential / building materials.

Claims (3)

Diene rubber polymer (a) in which two types of diene rubber polymers having a weight average particle diameter of 200 to 400 nm and 450 nm or more are blended so that the weight ratio is in the range of 9: 1 to 5: 5. Vinyl monomer mixture containing 25 to 40% by weight aromatic vinyl monomer (ii) and 10 to 20% by weight vinyl cyanide monomer (c) in the presence of 40 to 65% by weight 15 to 50 parts by weight of graft copolymer (I) obtained by graft copolymerization of 35 to 60% by weight,
Aromatic vinyl monomer (ii) 36 to 65% by weight, vinyl cyanide monomer (c) 0 to 12% by weight and maleimide monomer (d) 35 to 52% by weight were copolymerized. 10 to 38 parts by weight of the heat-resistant vinyl copolymer (II)
Highly cyanidated vinyl copolymer (III) 5 to 60 copolymerized with aromatic vinyl monomer (ii) 60 to 70% by weight and vinyl cyanide monomer (c) 30 to 40% by weight 60 parts by weight, and vinyl-based copolymerized aromatic vinyl-based monomer (a) more than 70% by weight to 82% by weight and vinyl cyanide-based monomer (c) 18% by weight to less than 30% by weight Containing 0 to 50 parts by weight of copolymer (IV) ,
For a total of 100 parts by weight of the graft copolymer (I), the heat resistant vinyl copolymer (II), the highly cyanated vinyl copolymer (III) and the vinyl copolymer (IV), ethylene / ( A heat- and paint-resistant thermoplastic resin composition comprising 0.5 to 10 parts by weight of a (meth) acrylic acid ester / carbon monoxide copolymer (V) . The heat-resistant and paint-resistant thermoplastic resin composition according to claim 1, wherein the highly vinyl cyanide copolymer (III) satisfies the following (A) and (B).
(A) The high vinyl cyanide copolymer (III) has an average vinyl cyanide content of 30 to 40% by weight.
(B) A copolymer having a composition higher by 2% by weight or more than the average vinyl cyanide content in the vinyl cyanide composition distribution of the highly vinyl cyanide copolymer (III) is a highly cyanidated vinyl copolymer. 20 to 50% by weight in (III). A molded product formed by molding the heat-resistant and paint-resistant thermoplastic resin composition according to claim 1.

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