JPH10330565A - Thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition improved in moldability and giving moldings improved in impact resistance and appearance by mixing a copolymer comprising an aromatic vinyl, an α,β-unsaturated dicarboxylic acid imide derivative and another vinyl with a copolymer comprising an aromatic vinyl, a vinyl cyanide and another vinyl and a graft polymer prepared by polymerizing an aromatic vinyl, vinyl cyanide or the like in the presence of a diene rubbery polymer. SOLUTION: This composition comprises 10-70 pts.wt. polymer (A) containing an α,β-unsaturated dicarboxylic acid imide derivative as a monomer, 0-50 pts.wt. polymer (B) containing a vinyl cyanide monomer and 10-50 pts.wt. graft polymer (C). Component C has a grafting ratio of 10% or above, contains 5-15 wt.% non-grafted polymer based on the total graft polymer composition. The intrinsic viscosity (in MEK at 30 deg.C) of the non-grafted polymer is 0.35 or below. It is desirable that components A and B are produced by bulk polymerization or suspension polymerization, and component C is obtained by emulsion graft polymerization. Components A, B and C are melt-kneaded to obtain the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin composition containing an α, β-unsaturated dicarboxylic acid imide derivative in a copolymerized unit and having excellent heat resistance, impact resistance, moldability, mechanical properties and productivity. It is about things.

[0002]

2. Description of the Related Art An acrylonitrile-butadiene-styrene copolymer (ABS resin) is known as a resin having excellent impact resistance due to dispersion of rubber particles in a matrix resin. The ABS resin is generally manufactured by a process of separately manufacturing and blending a graft polymer having a high rubbery polymer composition and a matrix resin. By this method, it is possible to improve the molding processability represented by impact resistance and fluidity and the physical properties of rigidity in a well-balanced manner. However, heat resistance is inferior to engineering plastics such as a polycarbonate resin and a modified PPE resin, so that the use thereof at high temperatures has been limited.

On the other hand, various techniques have been developed to supplement this heat resistance. Among them, blending a maleimide resin containing an α, β-unsaturated carboxylic acid imide derivative in a copolymerized unit is one of the heat decomposable materials. In recent years, it has been particularly often used because of its relatively good moldability.

[0004]

However, when a maleimide-based polymer is blended, the impact resistance and the moldability, which are the characteristics of the ABS resin, tend to be reduced. Therefore, an ABS resin containing a maleimide-based polymer is used in a state in which both impact resistance and molding processability are insufficient in consideration of a balance with heat resistance.

[0005]

Means for Solving the Problems As a result of intensive studies on solving the above problems, the present inventors have found that while maintaining the heat resistance improving effect of the maleimide resin, its impact characteristics, molding workability, rigidity, and surface appearance are maintained. It has been found that control of the graft properties of the graft polymer and the non-graft polymer is effective as a means for further improving such properties.

That is, the present invention relates to an aromatic vinyl monomer unit of 30 to 90% by weight, an α, β-unsaturated dicarboxylic acid imide derivative unit of 10 to 70% by weight, and other copolymerizable with these units. 10 to 70 parts by weight of a copolymer (A) composed of 0 to 50% by weight of vinyl monomer units, 50 to 99% by weight of aromatic vinyl monomer units, and 1 to 50 of vinyl cyanide monomer units % Of a copolymer (B) comprising 0 to 50% by weight of another vinyl monomer unit copolymerizable therewith.
Aromatic vinyl monomers, vinyl cyanide monomers and other vinyl monomers copolymerizable therewith in the presence of from 50 to 50 parts by weight and 65 to 85 parts by weight of a diene rubbery polymer And a graft polymer obtained by polymerizing 15 to 35 parts by weight of one or more monomers selected from the group consisting of:
% Or more, the weight ratio of the non-grafted polymer to the total graft polymer composition is 5 to 15% by weight, and the intrinsic viscosity of the non-grafted polymer measured at 30 ° C. in a methyl ethyl ketone solvent is 0.35 dl / g. A thermoplastic resin composition comprising 10 to 50 parts by weight of the following graft polymer composition (C). And the components (A) to (C) shown above.
A method for producing a thermoplastic resin composition, wherein the components are mixed in the ratio described above. ”.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below. In the present invention, weight means mass.

The first component used in the present invention, α, β
-The copolymer (A) containing the unsaturated dicarboxylic acid imide derivative can be obtained by the following two production methods. First, the first production method is a pre-imidization method in which a monomer of an α, β-unsaturated dicarboxylic acid imide derivative is copolymerized with another copolymerizable monomer, and the second production method is an α, β-unsaturated dicarboxylic acid imide derivative. β-
This is a post-imidization method in which an unsaturated dicarboxylic anhydride monomer is copolymerized with another copolymerizable monomer, followed by reaction with ammonia and / or a primary amine to perform imidization. For the copolymer (A) used in the present invention, any of these production methods can be used. However, when the post-imidization method is selected, α, β-unsaturated dicarboxylic anhydride is used as a copolymer component thereof. A copolymer containing a monomer unit of

The aromatic vinyl monomer which is a copolymer component includes styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene and o, p -Dichlorostyrene and the like, and styrene is particularly preferably used. These may be used alone or in combination of two or more.

When the pre-imidization method is selected, maleimide, N-methylmaleimide, N-ethylmaleimide,
Examples thereof include N-cyclohexylmaleimide, N-phenylmaleimide, and N-naphthylmaleimide, and N-phenylmaleimide is particularly preferably used. These may be used alone or in combination of two or more.

Next, when the post-imidization method is selected, α,
Examples of the monomer of the β-unsaturated dicarboxylic anhydride include anhydrides such as maleic acid, itaconic acid and citraconic acid, and maleic acid is particularly preferably used. These may be used alone or in combination of two or more. Examples of the imidizing agent used for imidization include ammonia, methylamine, ethylamine, cyclohexylamine, aniline, anisidine, toluidine, naphthylamine and the like, and aniline is particularly preferably used. These may be used alone or in combination of two or more.

Other vinyl monomers copolymerizable therewith include vinyl cyanide monomers, unsaturated carboxylic acid monomers, unsaturated carboxylic acid anhydride monomers, and unsaturated carboxylic acid anhydride monomers. A saturated carboxylic acid ester monomer or the like can be used. Specifically, acrylonitrile, methacrylonitrile, ethacrylonitrile, (meth) acrylic acid, maleic anhydride, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylate ) N-butyl acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, chloromethyl (meth) acrylate, (meth) acrylamide and the like.

The proportion of the aromatic vinyl monomer unit is 30 to 90% by weight, preferably 40 to 70% by weight, based on the copolymer (A). Cannot be sufficiently increased, and if it is less than 30% by weight, the balance of physical properties of the entire resin is unfavorably deteriorated.

The proportion of the α, β-unsaturated dicarboxylic imide derivative unit is 10 to 70% by weight, preferably 30 to 40% by weight, and preferably 50 to 40% by weight, irrespective of the production method. If the amount exceeds the above range, the balance of physical properties of the whole resin is deteriorated.

The object of the present invention can be achieved by using 50% by weight or less, preferably 20% by weight or less of other vinyl monomer units copolymerizable therewith.

Next, the copolymer (B) and the graft polymer (C) as the second component used in the present invention will be described.

As the diene rubbery polymer used in the graft polymer composition (C), a polymer or copolymer containing a conjugated diene as a main component is preferable. Among them, the content of the conjugated diene is preferably at least 75% by weight, particularly preferably at least 85% by weight. Specifically, polybutadiene, styrene-
Butadiene copolymer, acrylonitrile-butadiene copolymer, butyl acrylate-butadiene copolymer, isoprene rubber and the like can be used.

The average particle diameter of these diene rubbery polymers can be generally 0.1 to 0.6 μm, and particularly preferably 0.2 to 0.4 μm. The gel content is preferably 60% by weight or more in consideration of the impact resistance when blended with a thermoplastic resin. Here, the gel content indicates the weight fraction of the toluene-insoluble component after coagulation and drying of the rubbery polymer latex.

In the present invention, the monomers graft-polymerized in the presence of the rubbery polymer include an aromatic vinyl monomer and a vinyl cyanide monomer, and if necessary, other monomers copolymerizable therewith. It is a mixture of monomers.

Here, the graft polymer composition (C) of the present invention is used in an amount of 65 to 85 parts by weight, preferably 70 to 80 parts by weight, of the diene rubbery polymer, and the aromatic vinyl monomer and the cyanide are used. It is obtained by graft-polymerizing 15 to 35 parts by weight, preferably 20 to 30 parts by weight of a monomer mixture comprising a vinyl monomer and another vinyl monomer copolymerizable therewith. When the amount of the rubbery polymer exceeds 85 parts by weight, the effect of improving the impact resistance of the thermoplastic resin cannot be obtained due to a relative decrease in the graft ratio. Further, when the amount is less than 65 parts by weight, the non-grafted polymer having a low molecular weight produced simultaneously in the course of the graft polymerization embrittles the physical properties of the thermoplastic resin, and it is not possible to set the physical properties of the entire target resin in a well-balanced manner. Absent.

Styrene, α-methylstyrene, and styrene, α-methylstyrene
Examples include p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene, and o, p-dichlorostyrene, with styrene being particularly preferred. These may be used alone or in combination of two or more.

Examples of the vinyl cyanide-based monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, and acrylonitrile is particularly preferred. These may be used alone or in combination of two or more.

Other monomers copolymerizable therewith include unsaturated carboxylic acid monomers, unsaturated carboxylic acid anhydride monomers, unsaturated carboxylic acid ester monomers, and the like.
Alternatively, a maleimide-based monomer or the like can be used.
Specifically, (meth) acrylic acid, maleic anhydride,
Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, Chloromethyl (meth) acrylate, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, and N-phenylmaleimide can be used.

Here, the proportion of the aromatic vinyl monomer to be grafted is 50 to 99% by weight, preferably 60 to 90% by weight, more preferably 70 to 80% by weight, based on all monomers.
And the proportion of the vinyl cyanide monomer is 1 to 50% by weight, preferably 10 to 40% by weight, more preferably 20% by weight.
３０30% by weight. When the ratio of the aromatic vinyl monomer is 9
If the amount exceeds 9% by weight or less than 50% by weight, the desired resin properties cannot be obtained due to a decrease in compatibility with other blend components.

The object of the present invention can be achieved by using 50% by weight or less of other vinyl monomer units copolymerizable therewith.

The aromatic vinyl monomers used herein include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene and o, p-methylstyrene. Examples thereof include dichlorostyrene, and styrene is particularly preferably used. These may be used alone or in combination of two or more.

Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, and acrylonitrile is particularly preferred. These may be used alone or in combination of two or more.

Other monomers copolymerizable therewith include unsaturated carboxylic acid monomers, unsaturated carboxylic anhydride monomers, unsaturated carboxylic acid ester monomers, and the like.
A maleimide-based monomer or the like can be used. Specifically, (meth) acrylic acid, maleic anhydride, (meth)
Methyl acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n- (meth) acrylate
Butyl, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, chloromethyl (meth) acrylate, N-methylmaleimide, N-ethylmaleimide, N
-Cyclohexylmaleimide, N-phenylmaleimide and the like can also be used.

The proportion of the aromatic vinyl monomer is 50 to 99% by weight, preferably 60 to 90% by weight, based on all monomers.
It is more preferably 70 to 80% by weight, and the ratio of the vinyl cyanide monomer is 1 to 50% by weight, preferably 10 to 50% by weight.
It is 40% by weight, more preferably 20 to 30% by weight.
Even if the proportion of the aromatic vinyl monomer exceeds 99% by weight, 5
If the amount is less than 0% by weight, the physical properties of the resin composition deteriorate, which is not preferable. Further, the object of the present invention can be achieved by using 50% by weight or less of other monomers copolymerizable with these.

In order to easily control the balance of the desired resin properties, the polymer (A) and the graft polymer composition (C) are added (although not essential) to the aromatic vinyl polymer (B). ) Is preferred. The aromatic vinyl polymer (B) refers to an aromatic vinyl monomer unit of 50 to 99% by weight, a vinyl cyanide monomer unit of 1 to
It is a copolymer comprising 50% by weight and 0 to 50% by weight of another vinyl monomer unit which is not an essential component but can be copolymerized therewith. As the other copolymerizable vinyl monomers, the same monomers as those described above in the graft polymer composition (C) can be used. In particular, a copolymer composed of an aromatic vinyl monomer, a vinyl cyanide monomer, and another vinyl monomer copolymerizable therewith is more preferable. The ratio of the amount of the monomer is also preferably the ratio of the monomer which gives the graft polymer composition (C).

The resin composition of the present invention can be obtained by melt-kneading the above-mentioned copolymer (A), copolymer (B) and graft polymer (C). The melt-kneading method is not particularly limited, and may be a simple method using, for example, a single-screw extruder. The melt-kneading temperature is not particularly limited, but when the temperature is 210 to 270 ° C., preferably 230 to 250 ° C., the balance of the physical properties of the resin can be more easily set.

Here, the copolymer (A) is 10 to 70 parts by weight, preferably 30 to 50 parts by weight, and the copolymer (B) is 0% by weight.
５０50 parts by weight, graft polymer composition (C) is 10-5
The object of the present invention can be achieved by blending 0 parts by weight, preferably 20 to 40 parts by weight. If the amount of the copolymer (A) exceeds 70 parts by weight, the impact resistance is significantly reduced, and if the amount is less than 10 parts by weight, the effect of improving heat resistance cannot be obtained.

Here, in order to achieve the object of the present invention, it is necessary to set the properties of the graft polymer composition (C) as follows. First, the weight ratio (graft ratio) of the graft component to the rubbery polymer is 10% or more, preferably 15% or more. If the graft ratio is less than 10%, the compatibility between the rubbery polymer and the matrix resin is reduced, and the rubbery polymers may aggregate with each other at the time of melt-kneading, or the impact resistance of the resin is sufficiently exhibited. It is not preferable because it cannot be done. The proportion of the non-graft polymer generated in the course of the graft polymerization is 5 to 15% by weight, preferably 8 to 12% by weight based on the graft polymer, and is measured in a methyl ethyl ketone solvent of the non-graft polymer at 30 ° C. Intrinsic viscosity is 0.35 dl / g or less, preferably 0.1 to
0.30 dl / g.

The non-graft polymer contained in the graft polymer composition (C) of the present invention is characterized in that it has a lower molecular weight than a commonly used SAN resin or the like. Has a drastically improved melt fluidity. At the same time, this effect also leads to an increase in the state of dispersion of the rubbery polymer in the matrix after the melt-kneading, thereby contributing to the appearance effects of surface appearance and impact resistance. The intrinsic viscosity of the non-grafted polymer is 0.35
If it exceeds dl / g, this effect is impaired, which is not preferable.

On the other hand, if the proportion of the non-grafted polymer is too high, the molecular weight of the whole resin is lowered, and as a result, the resin tends to become brittle, so that the object of the present invention cannot be achieved. Therefore, it is necessary to control the proportion of the non-grafted polymer to 15% by weight or less based on the graft polymer. On the other hand, if the amount of the non-grafted polymer is less than 5% by weight, it is not preferable because the rubbery polymer is fused during the melt-kneading, thereby deteriorating the surface appearance and impact characteristics of the molded product.

In view of the above, in order to satisfy the characteristics of the above graft polymer, the ratio of the rubbery polymer to the graft polymer must be 55 to 85% by weight.
This means that for rubber contents less than 55% by weight, the non-grafted polymer formation is reduced to 15%
This is because a high grafting efficiency (ratio of the grafted monomer to all the monomers to be subjected to graft polymerization) cannot be expected to be as low as possible.

Further, in order to enhance the kneadability of the copolymer (A), the copolymer (B) and the graft polymer composition (C), a solvent of the copolymer (A) in methyl ethyl ketone at 30 ° C.
It is necessary to set the intrinsic viscosity measured in the above to 0.4 to 1 dl / g, preferably 0.5 to 0.8 dl / g. If the intrinsic viscosity exceeds 1 dl / g, kneading of the copolymer (A) and the graft polymer composition (C) becomes difficult, the dispersibility of the rubbery polymer decreases, and the impact resistance of the resin decreases. . Also,
If it is less than 0.40 dl / g, the whole resin becomes brittle and the impact resistance and mechanical properties are significantly reduced, which is not preferable.

The intrinsic viscosity of the copolymer (B) measured at 30 ° C. in a methyl ethyl ketone solvent is 0.3 to 0.8 d.
l / g, preferably 0.4-0.6 dl / g, is sufficient to achieve the object of the present invention.

Next, the method for producing each component is not particularly limited, and it can be produced by a generally known method.

For example, the copolymer (A) and the copolymer (B) can be produced by solution polymerization, emulsion polymerization, suspension polymerization, bulk polymerization, or the like. preferable. The graft polymer composition (C) can be obtained by emulsion graft polymerization.

In order to obtain each polymer component having properties within the desired range, polymerization time, polymerization temperature, type, amount and addition method of polymerization initiator, type, amount and addition method of chain transfer agent, If the composition ratio of the monomer, the addition time and the addition method, and the emulsion polymerization are selected, the type, the amount and the addition method of the emulsifier can be used.

In the emulsion polymerization of the graft polymer composition (C), the emulsifier, polymerization initiator and chain transfer agent used can be the same as those used in usual emulsion polymerization. Typical emulsifiers include potassium rosinate, potassium stearate, potassium oleate, and the like, and polymerization initiators include a combination of organic hydroperoxide and sugar-containing pyrophosphate-ferrous sulfate and a peracid salt. As the chain transfer agent, an alkylthiol compound is preferable, but the present invention is not limited thereto.

In addition, pigments and dyes for giving carbon black, titanium compounds and various dyes according to the purpose, phosphorus-based and phenol-based stabilizers, flame-retardants such as halogen-based compounds, antimony compounds and metal hydroxides, Phenol, phosphite and sulfur antioxidants, hindered phenol, benzotriazole, benzophenone, benzoate and cyanoacrylate UV absorbers, waxes, higher fatty acids and acid esters and acid amides Further, lubricants and plasticizers such as higher alcohols, antistatic agents such as amines, sulfonic acids, and polyethers, and fillers such as glass fibers, talc, and minerals can also be added.

[0044]

The present invention will be described in more detail with reference to the following examples.

The method for analyzing the copolymer and the graft polymer of the present invention is described below.

(1) Intrinsic Viscosity of Copolymer After the copolymer having been completely polymerized is sufficiently dried, about 0.4 g
/ 100cc of methyl ethyl ketone. The intrinsic viscosity of this solution was measured in a thermostat at 30 ° C.

(2) Graft ratio of graft polymer and weight ratio of non-graft polymer Acetone was added to a predetermined amount M (g) of the graft copolymer.
Refluxed for 4 hours. After the solution was centrifuged at 9,000 rpm for 30 minutes, insoluble components were filtered. 60 ° C
And dried under reduced pressure for 5 hours, and the weight N (g) was measured. The graft ratio G was calculated by the following equation. G = 100 × (N−M × L) / (M × L) Here, L represents the content of the rubbery polymer in the graft polymer.

The weight ratio F of the non-grafted polymer is
G was calculated by the following equation. F = 100 × (M−N) / M

(3) Intrinsic viscosity of the non-grafted polymer After filtering the insoluble matter from the acetone solution used for the measurement of the graft ratio, acetone was evaporated from the filtrate, and methanol was added to the residue to remove the non-grafted polymer. Extracted. After the extract was dried under reduced pressure at 60 ° C. for 3 hours, it was dissolved in methyl ethyl ketone, and the intrinsic viscosity of the solution was measured in a thermostat at 30 ° C.

Next, various physical property evaluation methods used in the examples are shown below.

(1) Melt Viscosity The melt viscosity was measured using a Shimadzu flow tester (CFT-500) under the following conditions. Plunger area: 1 cm ² Die hole diameter: 1 mm φ × 2 mm length Measurement temperature: 230 ° C Load: 50 kg / cm 2

(2) Izod impact strength Measured according to ASTM D-256 (1/2 inch, notched, 23 ° C.).

(3) Fish Eye Approximately 10 g of resin pellets before molding were heated and pressed at 250 ° C. and stretched to form a 10 μm thick film. The number of rubber-like lumps (bubbles) contained in the film 100 × 200 mm was visually measured. A film with a smooth surface is a case where the number of spots is 1 or less per 100 mm ² , and at this time, the surface appearance of the molded product is good. On the other hand, if the number of bumps exceeds 5 per 100 mm ² , the appearance of the molded product is significantly impaired.

(4) Deflection temperature under load Measured by ASTM D648 (１ ／ inch, load 1)
8.6 kg / cm ² ).

(5) Flexural modulus Measured according to ASTM D790 (８ inch, distance between spans 50 mm).

[Production Method of Copolymer (A)] Styrene 5
5 parts by weight, 30 parts by weight of N-phenylmaleimide and 15 parts by weight of acrylonitrile were subjected to suspension polymerization in a polymerization tank equipped with a reflux condenser and a stirring device. Using 0.15 parts by weight of azobisisobutyronitrile as an initiator and 0.12 parts by weight of t-dodecylmercaptan as a chain transfer agent, polymerization was carried out in ion-exchanged water in which saponified polyvinyl alcohol and hydroxycellulose were dissolved. However, since the monomer components have different reactivities, a monomer mixture of styrene and acrylonitrile was initially charged, and the temperature in the tank was reduced to 7%.
After the temperature was raised to 0 ° C, the remaining styrene and N-phenylmaleimide were continuously added by a plunger pump, and the polymerization was completed in 5 hours. As a result of measuring the intrinsic viscosity of the obtained bead-shaped resin, it was 0.58 dl / g.

[Production Method of Copolymer (B)] A monomer comprising 70 parts by weight of styrene and 30 parts by weight of acrylonitrile was subjected to suspension polymerization in the same polymerization tank as that of the copolymer (A) by the same method. A SAN copolymer was obtained. As a result of measuring the intrinsic viscosity of the obtained bead-shaped resin, it was 0.45 dl / g.

[Production Method of Graft Polymer Composition (C)] The diene rubbery polymer (PB) having the composition shown in Table 1 was used.
The latex of D) was charged into a glass reaction vessel, and while stirring, glucose, sodium pyrophosphate, and ferrous sulfate dissolved in ion-exchanged water were charged, and the temperature in the reaction vessel was raised to 65 ° C.

To this mixture, a mixture of styrene (ST), acrylonitrile (AN) and t-dodecyl mercaptan shown in Table 1 and an aqueous solution of potassium oleate of cumene hydroperoxide were separately added for 3 hours. The polymerization was completed by continuous dropping over 4 hours. All conversions ranged from 95 to 99%.

The obtained graft polymer latex is coagulated with sulfuric acid, neutralized with sodium hydroxide, washed with water, dehydrated,
After drying, a graft polymer powder was obtained. Graft ratio (G) of each graft polymer, weight ratio of non-graft polymer (F), and intrinsic viscosity (η) of methyl ethyl ketone soluble matter
Are summarized in Table 1.

[0061]

[Table 1]

[Production methods of Examples 1 to 3 and Comparative Examples 1 to 6] The copolymer (A), copolymer (B) and graft polymer composition (C) prepared above are shown in Table 2 respectively. While mixing at the indicated ratios, 1 part of ethylenebisstearylamide and 0.1 part of diphenylisodecylphosphite were added and mixed with a Henschel mixer. Next, 40mmφ
The mixture was extruded at a kneading temperature of 240 ° C. by a single screw extruder and pelletized. Each of the obtained resin compositions contains 18% by weight of the rubbery polymer and 15% by weight of the N-phenylmaleimide unit based on the resin composition.

In order to evaluate physical properties, a molding temperature of 240 ° C.
Injection molding was performed under the condition of a mold temperature of 70 ° C. to prepare predetermined test pieces. Table 2 shows the evaluation results of the physical properties.

[0064]

[Table 2]

The following is clear from the examples and comparative examples.

That is, the resin compositions containing the graft copolymer within the scope of the present invention (Examples 1 to 3) not only have excellent balance between moldability (melt viscosity) and impact resistance, but also Also, the surface appearance of the molded product is good.

On the other hand, even if the PBD content is 65 to 85% by weight, the resin composition whose graft property does not satisfy the range of the present invention (Comparative Examples 2 to 5) has the heat resistance maintained. However, many have low impact resistance and high melt viscosity as a whole. Further, there are many fish eyes, and the surface appearance of the molded article tends to be inferior. In particular, when the weight ratio (F value) of the non-grafted polymer falls below the range, the impact resistance and the surface appearance characteristics of the molded product are significantly deteriorated.

When the PBD content is 60% by weight or less,
It can be seen that suppressing the F value within the range is not practically suitable from the viewpoint of productivity and is inferior in impact resistance. Furthermore,
When the PBD content is 90% by weight, it is impossible to satisfy both the graft ratio and the range of the F value, and the physical properties of the resin are particularly low.

[0069]

Industrial Applicability The thermoplastic resin composition of the present invention further improves impact resistance, molding processability, and surface appearance characteristics of a molded product in a well-balanced manner while maintaining the heat resistance typical of a maleimide-based copolymer. This is advantageous in heat-resistant applications such as automobile parts and home electric appliances parts because the degree of freedom in physical properties is increased.This effect is due to the rubbery polymer content and graft ratio of the graft polymer to be blended. This is achieved by setting the weight ratio of the non-grafted polymer and the intrinsic viscosity thereof to a predetermined range.

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI C08L 55/02 C08L 55/02

Claims (4)

[Claims] 1. An aromatic vinyl monomer unit of 30 to 90% by weight, an α, β-unsaturated dicarboxylic acid imide derivative unit 10
(A) 10-70% by weight, and 0-50% by weight of other vinyl monomer units copolymerizable therewith
To 70 parts by weight, 50 to 99% by weight of an aromatic vinyl monomer unit, 1 to 50% by weight of a vinyl cyanide monomer unit, and 0 to another vinyl monomer unit copolymerizable therewith. 5
In the presence of 0 to 50 parts by weight of a copolymer (B) consisting of 0% by weight and 65 to 85 parts by weight of a diene rubbery polymer, aromatic vinyl monomers, vinyl cyanide monomers and A graft polymer obtained by polymerizing 15 to 35 parts by weight of at least one monomer selected from the group consisting of other vinyl monomers copolymerizable with The graft ratio of the polymer is 10% or more, the weight ratio of the non-grafted polymer to the total graft polymer composition is 5 to 15% by weight, and the non-grafted polymer is a methyl ethyl ketone solvent, measured at 30 ° C. The viscosity is 0.
Graft polymer composition (C) 1 having a content of 35 dl / g or less
A thermoplastic resin composition comprising 0 to 50 parts by weight. 2. The thermoplastic resin composition according to claim 1, wherein the intrinsic viscosity of the copolymer (A) measured at 30 ° C. in a methyl ethyl ketone solvent is 0.4 to 1 dl / g. 3. A graft polymer composition (C) wherein the vinyl monomer unit grafted is 50 to 99% by weight of an aromatic vinyl monomer unit and 1 to 50% by weight of a vinyl cyanide monomer.
3. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin composition comprises 1% by weight and 0 to 50% by weight of another vinyl monomer copolymerizable therewith. 4. An aromatic vinyl monomer unit of 30 to 90% by weight, an α, β-unsaturated dicarboxylic acid imide derivative unit 10
(A) 10-70% by weight, and 0-50% by weight of other vinyl monomer units copolymerizable therewith
To 70 parts by weight, 50 to 99% by weight of an aromatic vinyl monomer unit, 1 to 50% by weight of a vinyl cyanide monomer unit, and 0 to another vinyl monomer unit copolymerizable therewith. 5
In the presence of 0 to 50 parts by weight of a copolymer (B) consisting of 0% by weight and 65 to 85 parts by weight of a diene rubbery polymer, an aromatic vinyl monomer, a vinyl cyanide monomer and A graft polymer and a polymer obtained by polymerizing 15 to 35 parts by weight of one or more monomers selected from the group consisting of other vinyl monomers copolymerizable therewith, comprising: The graft ratio of the graft polymer is 10% or more,
The weight ratio of the non-grafted polymer to the total graft polymer composition is 5 to 15% by weight, and the intrinsic viscosity of the non-grafted polymer measured at 30 ° C. in a methyl ethyl ketone solvent is 0.35 dl / g or less. A method for producing a thermoplastic resin composition, comprising mixing 10 to 50 parts by weight of a graft polymer composition (C).