JP2617509B2 - N-substituted maleimide-containing thermoplastic resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a thermoplastic resin excellent in heat resistance and impact resistance, and more particularly to a thermoplastic resin composition containing an N-substituted maleimide. .

(Prior art and its problems) As a method for improving the heat resistance of a styrene-acrylonitrile copolymer, a method in which part or all of styrene is replaced with α-methylstyrene is often used. Further, in order to improve the heat resistance of a rubber-modified thermoplastic resin represented by an ABS resin, a method of using α-methylstyrene for one part of a monomer to be grafted, or a method of using α-methylstyrene for an ABS resin.
A method of blending a so-called heat-resistant AS resin composed of methylstyrene and acrylonitrile has been conventionally performed.

Since these thermoplastic resins have higher heat resistance than ordinary ABS resins, they are used as interior materials for automobiles and materials for OA equipment, but their heat resistance is still insufficient. For this reason, many attempts have been made to increase the α-methylstyrene content in the resin or to introduce maleic anhydride as another heat resistance improving component, but in any case, the thermal decomposition stability of the resin is unsatisfactory. Due to the sufficient heat resistance, there was a limit in improving the heat resistance.

A method of increasing the thermal decomposition stability by so-called post-imidization of a copolymer composed of an aromatic vinyl compound and maleic anhydride with a primary amine such as aniline has been attempted. Are disclosed in JP-B-62-8456. On the other hand, a composition of a copolymer resin containing an N-substituted maleimide and an ABS resin is also known, and for example, JP-A-59-232138 is exemplified. However, in any case, the balance between heat resistance and impact resistance is poor. For example, in order to increase heat resistance, a composite composition of a copolymer containing a large amount of N-substituted maleimide and an ABS resin is obtained, and the performance is obtained. When the impact resistance is not sufficient, on the other hand, the copolymer containing N-substituted maleimide is reduced to maintain the impact resistance, and a composite composition using a large amount of ABS resin is obtained. However, there is a problem that its heat resistance is not so high as compared with the conventional heat resistant ABS resin.

The present inventor is based on a thermoplastic resin containing an N-substituted maleimide compound, by adding an effective additive capable of improving impact resistance without lowering the heat resistance of a blend composition with an ABS resin. As a result of studying to solve the drawback of high heat resistance but low impact resistance, which is common in resins containing N-substituted imide compounds, a copolymer (A) of N-substituted maleimide and an aromatic vinyl compound was obtained. , Copolymer (B) of aromatic vinyl compound and vinyl cyanide compound and AB
By adding a small amount of the multilayer acrylic copolymer to 100 parts by weight of the S resin (II) composition, the impact resistance is improved while maintaining the high heat resistance characteristic of the imide-based resin, and processed. The present inventors have found that a novel thermoplastic resin having good properties can be obtained, and have reached the present invention.

(Means for Solving the Problem) That is, the present invention relates to a method comprising: preparing a random copolymer (A) from 20 to 65% by weight of an N-substituted maleimide and 35 to 80% by weight of an aromatic vinyl compound; A random copolymer (B) composed of 80% by weight, 18 to 50% by weight of a vinyl cyanide compound, and 0 to 10% by weight of a vinyl monomer copolymerizable therewith is prepared by mixing (A) 5 to 60% by weight and (B) 40 A heat-resistant resin (I) 40 to 70% by weight mixed at a ratio of 95 to 95% by weight, an aromatic vinyl compound 20 to 50% by weight and a vinyl cyanide compound 5 to 20% by weight, 100 to 100 parts by weight of a resin composition composed of 30 to 60% by weight of a copolymer (II) obtained by graft polymerization to 65% by weight, and a total of 50 to 80% by weight of a rubbery polymer, methyl methacrylate residues and styrene residues Is 20 to 50% by weight, and the ratio of styrene to methyl methacrylate is 0.5 to 1.5. That is to provide a multilayer acrylic polymer structure (III) is excellent in heat shock resistance comprising a 5 to 20 parts by weight N- substituted maleimide-containing thermoplastic resin composition.

The N-substituted maleimide which is a copolymer component in the random copolymer (A) used in the present invention is used in an amount of 20 to 65% by weight, particularly preferably 40 to 65% by weight. 20% by weight
If it is less than 1, the heat resistance of the random composition (A) itself is low, so that the heat resistance of the final composition is also low. On the other hand, when the content is 65% by weight or more, not only the copolymer (A) but also the final composition has poor melt fluidity and thermal decomposition stability. When the content is in the range of 40 to 65% by weight, the balance of physical properties such as heat resistance, impact resistance and fluidity of the final composition is good.

On the other hand, the aromatic vinyl compound is used in an amount of 35 to 80% by weight, preferably 35 to 60% by weight. If the amount of the aromatic vinyl compound is less than 35% by weight, the fluidity decreases, and if it exceeds 80% by weight, the heat resistance decreases, which is not preferable.

The production of the random copolymer (A) is carried out, for example, by melt polymerization, and the polymerization method is, for example, a method in which an aromatic vinyl compound and an N-substituted maleimide are charged into a reaction vessel at a time and then polymerized. Group vinyl compound and a small amount of N-
After charging the substituted maleimide, any method such as continuous addition of the remaining N-substituted maleimide during polymerization and polymerization is possible. As a polymerization initiator used at this time, a radical initiator such as dilauroyl peroxide is used, and as a solvent, toluene, methyl ethyl ketone or chloroform can be used. , Methyl ethyl ketone (MEK) is particularly preferred. The polymerization temperature can be arbitrarily selected within the range of 70 to 120 ° C.
The above high temperature, and in order to increase the degree of polymerization, 70-80
A low temperature of ° C is desirable.

Examples of the aromatic vinyl compound constituting the random copolymer (A) include styrene, α-methylstyrene, p-methylstyrene and the like. Among them, it is particularly preferable to use styrene and α-methylstyrene alone or a mixture thereof.

The N-substituted maleimide constituting the random copolymer (A) includes N-phenylmaleimide, N-cyclohexylmaleimide and N- (2,4,6-tribromo)
At least one monomer selected from -phenylmaleimide can be used.

The solution viscosity [η] of the random copolymer (A) is preferably from 0.3 to 1.0 under the measurement conditions of 30 ° C. in tetrahydrofuran. If it is less than 0.3, the impact resistance decreases. [Η]
If it is 1.0 or more, the melt fluidity is undesirably reduced.

The aromatic vinyl compound which is a copolymer component of the random copolymer (B) used in the present invention is 50 to 82% by weight, preferably 65 to 82% by weight, and the vinyl cyanide is 18 to
50% by weight, preferably 18-35% by weight, 0-10% by weight of other copolymerizable vinyl monomers are used. Outside these ranges, the physical properties of (B), particularly heat and impact resistance, are undesirably reduced. As the aromatic vinyl compound constituting the random copolymer (B), the same compound as constituting the random copolymer (A) can be used. As the vinyl cyanide, acrylonitrile, methacrylonitrile, and the like can be used, and acrylonitrile is most preferable. In addition, as a copolymerizable vinyl monomer,
Examples include acrylates such as methyl acrylate, methacrylates such as methyl methacrylate and ethyl methacrylate.

For the production of the random copolymer (B), the same solution polymerization method or suspension polymerization method as the random copolymer (A) can be used. In the case of the suspension polymerization method, a mixture of an aromatic vinyl compound and a vinyl cyanide compound is put into an aqueous solution containing a calcium phosphate-based dispersant to form a suspension, and a radical initiator such as benzoyl peroxide is added under a nitrogen atmosphere. The copolymer (B) can be obtained in the form of beads by polymerizing at 75 to 90 ° C. for about 10 hours as a polymerization catalyst.
Bead-shaped polymers are particularly effective because they are easily mixed with the powder of the random copolymer (A).

The solution viscosity [η] of the random copolymer (B) is preferably from 0.5 to 1.5 as measured under the same conditions as for the random copolymer (A). When [η] is 0.5 or less, the impact resistance is low. [Η] is
If it exceeds 1.5, the fluidity becomes low, which is not preferable. If the copolymerizable vinyl monomer is used in an amount of 10% by weight or more, the heat resistance and the like of the random copolymer (B) are undesirably reduced.

As for the composition ratio of the random copolymer (A) and the random copolymer (B) constituting the copolymer composition (I), (A) is preferably 5 to 60% by weight. (A) is 5% by weight
If less than the above, the heat resistance of the final composition is impaired, and conversely (A)
If it exceeds 60% by weight, the fluidity and thermal decomposition stability of the final composition are undesirably reduced.

The copolymer (II) used in the present invention contains 20 to 55% by weight of an aromatic vinyl compound (for example, 20 to 50% by weight), preferably 25 to 55% by weight, and 5 to 25% by weight of a vinyl cyanide compound (for example, , 5 to 20% by weight), preferably 15 to 25% by weight, is graft-polymerized to 30 to 65% by weight, preferably 30 to 50% by weight of a rubbery polymer. If the mixing ratio of the monomer mixture to be graft-polymerized is out of this range, the blendability of the mixture of the random copolymer (A) and the random copolymer (B) is poor, and the physical properties of the final composition, particularly, impact resistance Is less effective. If the amount of the rubbery polymer is less than 30% by weight, the copolymer (II)
Has a low impact resistance, and that of the final composition likewise has a low impact resistance. On the other hand, when the content exceeds 65% by weight, the impact resistance increases, but the heat resistance and the melt fluidity decrease.

As the aromatic vinyl compound and vinyl cyanide compound of the copolymer (II), the same monomers as in the random copolymer (A) can be used. As the rubbery polymer, polybutadiene rubber, styrene-butadiene copolymer rubber, acrylic rubber or ethylene-propylene rubber can be used.

The copolymer (II) can be produced by a known emulsion polymerization method or bulk suspension polymerization method. However, in order to obtain a copolymer having a high rubber content, the above monomer is added to the rubber-like polymer latex. Emulsion polymerization methods in which the mixture is grafted are advantageous.

The acrylic copolymer (III) used in the present invention is:
It is a composite modifier composed of a rubbery polymer having a multilayer structure, methyl methacrylate and styrene. As the multilayer structure, for example, (1) a multilayer structure in which a hard layer is provided at a central portion, a soft layer is formed of a rubber-like polymer as a second layer, and a surface layer thereof is formed of a hard layer; 2) each layer forms a substantially linked polymer, the hard layer being a multi-layered structure formed of a polymer of styrene or methyl methacrylate alone or a mixture, (3) a rubbery polymer having a methyl methacrylate A multi-layer structure in which a monomer mixture of styrene and styrene is graft-polymerized in several layers; (4) a core formed by polymerization of a monomer system containing polybutadiene, styrene, methyl methacrylate and divinylbenzene as a crosslinking agent; Second stage polymerized layer by polymerization of styrene and methyl methacrylate and 1,
Examples thereof include a core-shell polymer having a final stage (shell) in which 3-butylene glycol dimethacrylate is polymerized.

These production methods can be produced by a known method, for example, the central portion is formed by emulsion polymerization, and the soft portion is successively subjected to emulsion polymerization,
There are a method of forming a hard part to form a multilayer structure, and a method of forming a graft by emulsion polymerization, and then forming a similar graft on the graft by emulsion polymerization to form a multilayer structure.

The rubbery polymer in the multilayer structure is the same as the rubbery polymer used for the copolymer (II), and among them, polybutadiene rubber is particularly preferred. The amount of the rubbery polymer in the multi-layer acrylic copolymer (III) is 50 to 8
Desirably, it is 0% by weight. If it is less than 50% by weight, the modifying effect, especially the impact resistance improving effect, is poor.

On the other hand, the amount of styrene and methyl methacrylate to be grafted on the rubbery polymer is 20 to 50% by weight in total.
Is desirable. Outside this range, the effect of adding the copolymer (III) as a modifier is not sufficient.

On the other hand, the weight ratio of styrene to methyl methacrylate is 0.
The range is preferably from 5 to 1.5, and particularly preferably from 0.8 to 1.2.
At a ratio outside the above range, the degree of improvement in impact resistance, which is an effect of the present invention, is low.

The addition amount of the copolymer (III) for obtaining the composition of the present invention is 5 to 20 parts by weight based on 100 parts by weight of the total amount of (I) + (II).
It is desirable to add parts by weight. If the amount is less than 5 parts by weight, the effect of improving the impact resistance by the addition is poor. If the amount is more than 20 parts by weight, the heat resistance of the final composition is reduced.

The composition ratio of (I) + (II) in 100 parts by weight is as follows:
(I) is preferably 40 to 70% by weight. If (I) is less than 40% by weight, the heat resistance is low, and if it exceeds 70% by weight, the impact resistance of the final composition is reduced.

The mixing method for obtaining the composition of the present invention can be carried out by any method. For example, the composition is produced by kneading with a Banbury mixer, a roll, an extruder or the like.

In the composition of the present invention, a heat stabilizer such as an antioxidant, various additives such as an ultraviolet absorber, a reinforcing agent such as a glass fiber and a metal fiber, and a filler can be mixed during or after the kneading. .

(Examples) Hereinafter, the present invention will be specifically described using examples. Unless otherwise specified, parts or% are based on weight.

[Production of copolymer (A)]

The inside of a reactor equipped with a stirrer is replaced with nitrogen, and MEK
・ 100 parts, α-methylstyrene (αMeSt) ・ 60 parts, N-
5 parts of phenylmaleimide (pMI) and 0.2 parts of polymerization initiator lauroyl peroxide (LPO) were added all at once. While flowing a small amount of nitrogen, the temperature was raised from outside with a heating medium.
Polymerization was started when the internal temperature reached 75 ° C, and at that temperature, 3.
Polymerization was carried out for 5 hours. During the polymerization, 35 parts of pMI was additionally added at a rate of 10 parts per hour. After the completion of the polymerization, the inside was rapidly cooled, the dope was transferred to a stainless steel container, and devolatilized in a vacuum dryer. The devolatilized block-like sample was pulverized by a pulverizer. Analysis of this powder sample by IR spectrum showed that αMeSt was 58% and pMI was 42%.
[Η] measured at 30 ° C. in THF was 0.50. In addition, the copolymer (A) was similarly produced by changing the kind of the monomer and the charged amount. Table 1 shows the composition and the like.

[Production of Copolymer (B)] The inside of a reactor equipped with a stirrer was replaced with nitrogen, and St.
72 parts, acrylonitrile (An), 28 parts, benzoyl peroxide (BPO) 0.35 part as a polymerization initiator, tertiary decyl mercaptan (TDM), a molecular weight regulator
0.18 parts of the mixture was charged and mixed well. Then, 100 parts of an aqueous dispersion containing 0.2 part of a calcium phosphate dispersant and 0.01 part of sodium dodecyl sulfate as a dispersion stabilizing aid was added to the monomer mixture, and the mixture was stirred at high speed to form a suspension. The polymerization was started at an internal temperature of 75 ° C., and after maintaining at that temperature for 6 hours, the internal temperature was further raised to 85 ° C., and the polymerization was continued for 2 hours. After decomposing the dispersant with hydrochloric acid,
After filtration, washing and drying, a bead polymer having a particle size of about 0.2 mm was obtained. The yield was 98%. Table 2 shows the contents of [resin (B)] having different polymer compositions obtained in the same manner.

[Copolymer II] As the copolymer II, the resins shown in Table 3 (manufactured by Nippon Synthetic Rubber Co., Ltd.) were used.

[Production of Acrylic Copolymer / (III)] The acrylic copolymer / (III) in the present invention was produced as follows.

<First Stage Polymerization> In a flask, 58 parts of polybutadiene (PBD) latex in terms of solid content, 15 parts of ion-exchanged water (DW), 8 parts of styrene (St), 6 parts of methyl methacrylate (MMA),
A monomer mixture consisting of 0.9 parts of divinylbenzene was added, and the internal temperature was raised to 60 ° C. Then sodium pyrophosphate 0.02 parts, ferrous sulfate hydrate 0.001 part, glucose
A solution prepared by dissolving 0.04 part in 2.0 parts of DW was added, and 0.03 part of cumene hydroperoxide (CPO) was added. After nitrogen replacement, polymerization was carried out at 70 ° C. for 1 hour.

<Second Stage Polymerization> In a reaction vessel containing the polymerization product of the first stage, sodium dodecylbenzenesulfonate (SDS) 17% and sodium formaldehyde sulfoxylate (SFS)
After adding 5 parts of an aqueous solution containing 5%, St. 11 parts and CH
A mixture of 0.01 part of PO was continuously added for 20 minutes, and polymerization was continued for another 40 minutes after the addition was completed.

<Third-step polymerization> The reaction vessel containing the polymerization product after the second step
5 parts of an 8% aqueous solution of S was added, and the mixture was controlled at 80 ° C.
Then, 11 parts of MMA, a mixture of 0.1 part of 1,3-butylene glycol dimethacrylate, 0.1 part of tertiary decyl mercaptan, 0.02 part of CPO and 0.03 part of CPO were continuously added for 20 minutes, and further polymerized for 40 minutes, A three-layer core-shell polymer was obtained in a latex state.

The latex thus obtained was coagulated with calcium chloride, washed with water and dried to obtain a white polymer. Analysis of this polymer showed that the PBD content = 60%, MMA = 20%, St = 19
%, The crosslinker component was about 1%. This polymer is referred to as (II
I) _Let it be a. The results of analysis of the polymerized (III) _b with the amounts of the PBD latex and monomer charged outside the range of the present invention are shown in Table-4.

[Evaluation Method of Physical Properties] Physical properties were evaluated according to the items shown in Table 5 below.

Example 1 30 parts of the copolymer (A-1) and 30 parts of the copolymer (B-1) shown in the production examples were dry-blended in a polyethylene bag in the form of powder and beads, and then copolymerized. Polymer ・ (II-1) ・
After weighing 40 parts and 10 parts of (III) _a as a core-shell polymer, respectively, Irganox 10 was used as a heat stabilizer.
0.22 parts of 10 (manufactured by Ciba Geigy) was added, and the mixture was well dry-blended in powder form. This composition comprises (A-1) / (B-
1) = 50/50 and (I) / (I + II) = 60/100. Note that (III) _a / (I + II) = 10/100. This powder blend was fed to Osaka Seiki Co., Ltd. 40 mm vent extruder, and the cylinder temperature was 240 ° C and the screw rotation speed was 80r.
Kneading and extrusion were performed at pm. Next, a molded specimen for evaluating physical properties was obtained from the pellet using an injection molding machine manufactured by Nissei Plastic Industry Co., Ltd.

When the molded specimen was evaluated according to the physical property evaluation items described in the preceding section, HDT = 116 ° C., IS = 18 kg · cm / cm, and MFR = 1.
2 g / 10 min, good balance of heat resistance, impact resistance, and melt fluidity, and good appearance with almost no coloring of the molded specimen.

[Example 2] The same experiment as in [Example 1] was conducted except that the same amount of the copolymer (A-2) containing a small amount of styrene was used instead of the copolymer (A-1). . This system has a composition ratio (A
-2) / (B-1) = 50/50, (I) / (I + II) = 60 /
100, and (III) _a / (I + II) = 10/100. The results of evaluating the injection-molded product of the obtained composition pellets are shown in Table-6. This composition was also excellent in physical properties.

[Example 3] In [Example 1], cyclohexylmaleimide was copolymerized in place of the copolymer (A-1) (A-3).
This is an example using. Also in this example, (A-3) / (B-1) = 50
/ 50, (I) / (I + II) = 60/100. As a result of an experiment conducted in the same manner as in [Example 1], as shown in Table 6, the physical properties of the molded specimen were high in heat resistance and impact resistance and good in fluidity.

[Example 4] Instead of the copolymer (A-1) of [Example 1], N
This is an example using a copolymer (A-4) obtained by copolymerizing-(2,4,6-tribromo) phenylmaleimide. The composition ratio is
This is exactly the same as [Example 1]. Table 6 shows the results of evaluating the physical properties of the injection-molded product of this composition. In this example, although the impact resistance was slightly lower than the previous example, the heat resistance was very high.

Example 5 In Example 2, the amount of the core-shell polymer (III) _a was increased from 10 parts to 15 parts with respect to 100 parts of I + II. As shown in Table 6, the evaluation results in this case showed that the heat resistance was slightly lower than that of the previous example, but the impact resistance was further improved and the physical properties were excellent.

Comparative Example 1 This example is an example in which the core-shell polymer was not added to [Example 1]. In this case, (A-1) /
(B-1) = 50/50, (I) / (I + II) = 60/100. The composition was kneaded and extruded, and the physical properties were evaluated. As a result, as shown in Table 6, the heat resistance of the molded product was high, but the impact resistance was low, and the physical properties were not satisfactory.

[Comparative Example 2] This is an example in which (III) _b which is out of the scope of the present invention was used as the core-shell polymer in [Example 1]. The composition ratio at this time is the same as in [Example 1]. Physical properties of the molded sample in this case were measured. As shown in Table 6, the heat resistance was high, but the effect of using the core-shell polymer as a modifier was poor and the impact resistance was low.

[Comparative Example 3] In this example, the copolymer (B-
Instead of 1), the copolymer (B-
This is an example using 2). The composition ratio of the component resins is exactly the same as in [Example 1], but (B-2) is a copolymer (I)
Due to poor compatibility with I), the composition obtained as shown in Table-6 had low impact resistance.

[Comparative Example 4] This is an example using (II-2) which is out of the scope of the present invention as the copolymer (II) in [Example 2]. The composition ratio was the same as that of [Example 2], but (II-2) had a low rubber content, so that the impact resistance of the final composition was low as shown in Table-6.

Example 6 In this example, as shown in Table 7, 36 parts of (A-2) and (B-
1) 29 parts, (II-1) 35 parts, and (III) _a 10 parts, respectively. In this case, (A-2) / (B-1)
= 55/45, (I) / (I + II) = 55/100, and (I + I
It corresponds to (III) _a = 10 parts for I) = 100 parts. As shown in Table 7, the physical properties of the molded specimen of this composition were high in heat resistance and impact resistance.

Example 7 In this example, (A-4) 25 parts, (B-1) 20 parts, (II
-1) and 55 parts of modifier (III) _a.8 parts, wherein (A-4) / (B-1) = 55.6 / 44.4, (I) /
(I + II) = 45/100. Also in this case, as shown in Table 7, the impact resistance was slightly lower than that of Example 4 but, instead, the heat resistance was excellent.

[Example 8] This example is an example implemented in the same manner as [Example 1] using (A-5) in which methyl methacrylate was introduced as the third monomer into the copolymer (A). This example is also (A-
5) / (B-1) = 50/50, (I) / (I + II) = 60/10
It is 0. The results of evaluating the physical properties of this composition are shown in Table 7, and it was found that heat resistance, impact resistance and melt fluidity were balanced.

[Comparative Example 5] In this example, the type of the copolymer was the same as that in [Example 2], but the composition ratio was out of the range. In this case, (A-2) / (B-1) = 50/50, but (I)
/ (I + II) = 30/100. The physical properties of the composition at this time are shown in Table 7, which showed high impact resistance but low heat resistance and low melt fluidity.

[Comparative Example 6] In this example, (A-2) / (B-1) = 50/50, but (I) / (I + II) = 90/100, which was outside the scope of the present invention. It is. The results of evaluation of physical properties in this case are shown in Table-7. The heat resistance was very high, but the impact resistance was lowered.

[Comparative Example 7] In this example, the type of the copolymer is the same as in Example 1 but using 30 parts of the modifier (III) _a , which is outside the scope of the present invention. is there. As shown in Table 7, the heat resistance was as low as 92 ° C.

[Effects of the Invention] As a result of the present invention, the problem that conventional imide-modified styrene resins have high heat resistance but low impact resistance has been solved. Therefore, both heat resistance and impact resistance are excellent,
In addition, it has become possible to supply new resin materials that have the characteristics of styrene-based resins, which are excellent in moldability and low in price, as chassis members for OA equipment and interior materials for automobiles.

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Claims (3)

(57) [Claims] 1. A random copolymer (A) comprising 20 to 65% by weight of an N-substituted maleimide and 35 to 80% by weight of an aromatic vinyl compound, 50 to 82% by weight of an aromatic vinyl compound, and a vinyl cyanide compound
A random copolymer (B) consisting of 18 to 50% by weight and 0 to 10% by weight of a vinyl monomer copolymerizable therewith,
(A) 5 to 60% by weight, (B) 40 to 95% by weight of heat-resistant resin (I) 40 to 70% by weight, aromatic vinyl compound 20 to 55% by weight, vinyl cyanide compound 5 to 25% by weight of a copolymer (II) obtained by graft polymerization of 30 to 65% by weight of a rubbery polymer to 100% by weight of a resin composition comprising 30 to 60% by weight of a rubbery polymer 50 to 80% by weight %, The total of methyl methacrylate residues and styrene residues is 20 to 50% by weight, the ratio of styrene to methyl methacrylate is 0.5 to 1.5, and a multilayer structure which may be cross-linked with a cross-linking agent if necessary. An N-substituted maleimide-containing thermoplastic resin composition having excellent thermal shock resistance, comprising 5 to 20 parts by weight of the acrylic polymer (III). 2. The N-substituted maleimide is N-phenylmaleimide, N-cyclohexylmaleimide and N- (2,4,
The N-substituted maleimide-containing thermoplastic resin composition according to claim 1, which is at least one member selected from 6-tribromo) phenylmaleimide. 3. The method according to claim 1, wherein the aromatic vinyl compound is styrene, α-methylstyrene or a mixture thereof.
A substituted maleimide-containing thermoplastic resin composition.