MALEIMIDE-BASED COPOLYMER, MALEIMIDE-BASED COPOLYMER COMPOSITION, RESIN COMPOSITION, AND INJECTION MOLDED BODY

Abstract

A maleimide-based copolymer which allows to obtain a resin composition having balanced heat resistance providing property and impact resistance, superior flowabillty, and low yellowness (YI); a maleimide-based copolymer composition using such maleimide-based copolymer; a resin composition.; and an injection molded body are provided. A maleimide-based copolymer, including: aromatic vinyl monomer unit, vinyl cyanide monomer unit, and maleimide monomer unit; wherein: the maleimide-based copolymer has a weight average molecular weight of 50,000 to 110,000; and the maleimide-based copolymer has a mid-point glass transition temperature measured in accordance with JIS K-7121 of 165° C. to 200° C., is provided.

Claims

1. A maleimide-based copolymer, comprising: aromatic vinyl monomer unit, vinyl cyanide monomer unit, and maleimide monomer unit; wherein: the maleimide-based copolymer has a weight average molecular weight of 50,000 to 110,000; and the maleimide-based copolymer has a mid-point glass transition temperature measured in accordance with JIS K-7121 of 165° C. to 200° C.

2. The maleimide-based copolymer of claim 1, wherein the maleimide-based copolymer has a yellowness measured in accordance with JIS K-7373 of 0.5 to 3.5.

3. The maleimide-based copolymer of claim 1, wherein the maleimide-based copolymer comprises 40 to 60 mass % of the aromatic vinyl monomer unit, 5 to 20 mass % of the vinyl cyanide monomer unit, and 30 to 50 mass % of the maleimide monomer unit as a monomer unit constituting the maleimide-based copolymer.

4. A maleimide-based copolymer composition, comprising: 100 parts by mass of the maleimide-based copolymer of claim 1; and 0 to 20 parts by mass of a copolymer other than the maleimide-based copolymer; wherein: the copolymer other than the maleimide-based copolymer comprises vinyl cyanide monomer unit and aromatic vinyl monomer unit.

5. A resin composition, comprising: 5 to 40 mass % of the maleimide-based copolymer of claim 1; and 60 to 95 mass % of one or two or more of a resin selected from the group consisting of: acrylonitrile-butadiene-styrene copolymer resin, acrylonitrile-styrene-acryl based rubber copolymer resin, acrylonitrile-ethylene propylene based rubber-styrene copolymer resin, and styrene-acrylonitrile copolymer resin.

6. A resin composition, comprising: 5 to 40 mass % of the maleimide-based copolymer composition of claims 4; and 60 to 95 mass % of one or two or more of a resin selected from the group consisting of: acrylonitrile-butadiene-styrene copolymer resin, acrylonitrile-styrene-acryl based rubber copolymer resin, acrylonitrile-ethylene propylene based rubber-styrene copolymer resin, and styrene-acrylonitrile copolymer resin.

7. An injection molded body made from the resin composition of claim 5.

8. The injection molded body of claim 7 used as an interior component or an exterior component of an automobile.

Description

EXAMPLE

[0091] Hereinafter, detailed explanation is provided with reference to Examples. However, the present invention is not limited to the following Examples.

<Production Example of Maleimide-Based Copolymer (A-1)>

[0092] To an autoclave having a capacity of about. 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution. prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.6 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain. pellet maleimide-based copolymer A-1. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-2)

[0093] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 21 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy ethylhexanoate, 0.5 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 26 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 19.9 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization. solution, and reaction was carried out at 140° C. for 7 hours, The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed. to obtain pellet maleimide-based copolymer A-2. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-3)>

[0094] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.75 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120 and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.8 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization. solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction. solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed. to obtain pellet maleimide-based copolymer A-3. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based. Copolymer (A-4)>

[0095] To an autoclave having a capacity of about 1.2.0 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t/butylperoxy-2-ethylhexanoate, 0.2 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 7.5 parts by Mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.7 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion. of reaction. was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer A-4. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-5)>

[0096] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by Mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 11.9 parts by mass of aniline and 0.2 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion. of reaction. was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer A-5. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-6)>

[0097] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 23.0 parts by Mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer A-6. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-7)>

[0098] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 20 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of u-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 28 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 27 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 25.4 parts by mass of aniline and 0.4 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed. to obtain pellet maleimide-based copolymer A-7. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (A-8)>

[0099] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 15 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 28 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 4 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 20.1 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion. of reaction. was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer A-8. Results of analysis for the maleimide-based copolymer are shown in Table 1.

<Production Example of Maleimide-Based Copolymer (B-1)>

[0100] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 5 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.025 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept. at 92° C., and a solution prepared by dissolving 25 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.6 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at. 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed. to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-1. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-2)>

[0101] To an autoclave having a capacity of about. 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 6 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation After raising the tel the temperature was kept at 92° C., and a solution prepared by dissolving 24 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.9 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-2. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-3)>

[0102] To an autoclave having a capacity of about. 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 7 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy ethylhexanoate, 0.1 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 23 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.6 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization. solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed. to obtain pellet maleimide-based copolymer B-3. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-4)>

[0103] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 21 parts by mass of acrylonitrile, 8 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.025 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 23 parts by mass or maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 19.2 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-4. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-5)>

[0104] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 9 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoat, 0.025 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at. 92° C., and a solution prepared by dissolving 21 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanbate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.7 parts by mass of aniline and 0.3 parts by mass of triethylamine were added. to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-5. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-6)

[0105] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 10 parts by mass of acrylonitrile, 10 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy ethylhexanoate, 0.025 parts by mass of α-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 20 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy ethylhexanoate in 75 parts by mass of methyl ethyl ketone and 28 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, 12 parts by mass of styrene was added continuously over 2 hours. After adding styrene, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 18.7 parts by mass of aniline and 0.3 parts by mass of triethylamine were added to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-6. Results of analysis for the maleimide-based copolymer are shown in Table 2.

<Production Example of Maleimide-Based Copolymer (B-7)>

[0106] To an autoclave having a capacity of about 120 liters equipped with an agitator, 20 parts by mass of styrene, 22 parts by mass of acrylonitrile, 13 parts by mass of maleic anhydride, 0.1 parts by mass of t-butylperoxy-2-ethylhexanoate, 0.5 parts by mass of n-methyl styrene dimer, and 12 parts by mass of methyl ethyl ketone were charged. After replacing the gaseous phase of the system with nitrogen gas, the temperature was raised to 92° C. over 40 minutes with agitation. After raising the temperature, the temperature was kept at 92° C., and a solution prepared by dissolving 18 parts by mass of maleic anhydride and 0.22 parts by mass of t-butylperoxy-2-ethylhexanbate in 75 parts by mass of methyl ethyl ketone and 27 parts by mass of styrene were added continuously over 7 hours. Further, after completion of the addition of maleic anhydride, the temperature of the reaction mixture was raised to 120° C., and the reaction was carried out for 1 hour to complete polymerization. Thereafter, 19.2 parts by mass of aniline and 0.3 parts by mass of triethylamine were added. to the polymerization solution, and reaction was carried out at 140° C. for 7 hours. The imidizing reaction solution after completion of reaction was fed to a vent type screw extruder, and the volatile component was removed to obtain pellet maleimide-based copolymer B-7. Results of analysis for the maleimide-based copolymer are shown in Table 2.

TABLE-US-00001 TABLE 1 A-1 A-2 A-3 A-4 A-5 A-6 A-7 A-8 constitution aromatic vinyl monomer unit mass % 49.1 39.4 48.5 49.0 48.8 48.8 38.3 41.5 unit vinyl cyanide monomer unit mass % 8.0 14.8 8.2 7.8 8.1 8.1 14.2 12.0 unsaturated dicarboxylic anhydride mass % 1.1 1.2 1.1 1.1 16.3 0.0 0.0 1.3 monomer unit maleimide-based monomer unit mass % 41.8 44.7 42.2 42.1 26.8 43.1 47.5 45.3 molecular weight (×10.sup.4) Mw 7.9 9.6 6.0 10.9 7.8 8.1 8.5 8.7 MFR (265° C., 98N) g/10 min 72 81 63 38 75 68 83 34 mid-point glass transition temperature ° C. 170 167 165 172 168 172 166 169 amount of residual maleimide monomer ppm 200 220 200 200 1720 90 100 220 YI — 2.0 3.3 0.8 3.4 2.0 2.0 3.2 2.8

TABLE-US-00002 TABLE 2 B-1 B-2 B-3 B-4 B-5 B-6 B-7 constitution aromatic vinyl monomer unit mass % 49.1 48.4 48.8 38.9 48.8 48.8 38.1 unit vinyl cyanide monomer unit mass % 8.0 8.0 8.2 16.8 8.1 8.1 17.6 unsaturated dicarboxylic anhydride mass % 1.1 1.1 1.2 1.1 1.1 1.1 1.1 monomer unit maleimide-based monomer unit mass % 41.8 42.5 41.9 43.2 41.9 42.0 43.2 molecular weight (×10.sup.4) Mw 13.7 15.7 12.6 13.6 14.6 14.7 4.6 MFR (265° C., 98N) g/10 min 15 18 17 19 22 11 71 mid-point glass transition temperature ° C. 170 170 164 170 166 172 170 amount of residual maleimide monomer ppm 200 200 200 200 200 200 200 YI — 4.4 4.5 4.1 8.1 4.4 4.4 2.0

(Weight Average Molecular Weight)

[0107] The weight average molecular weight a value of polystyrene equivalent measured by gel permeation chromatography (GPC), which was measured under following conditions.

[0108] Name of Instrument: SYSTEM-21 Shodex (available from Showa Denko K. K.)

[0109] Column: PL gel MIXED-B (available from Polymer Laboratories Ltd.), 3 columns connected in series

[0110] Temperature: 40° C.

[0111] Detection: differential refractive index

[0112] Eluent: tetrahydrofuran

[0113] Concentration: 2 mass %

[0114] Calibration Curve: standard polystyrene (PS) (available from Polymer Laboratories Ltd) was used for preparation

(Melt Mass Flow Rate)

[0115] Melt mass flow rage was measured in accordance with JIS K-7210, using the following instrument under the following measurement conditions.

[0116] Name of Instrument: No. 120 Melt-Flow Rate Tester (available from YASUBA SEIKI SEISARUSHO, LTD.)

[0117] Temperature: 265° C.

[0118] Load: 98 N

(Mid-Point Glass Transition Temperature (Ting))

[0119] Mid-point glass transition temperature was measured in accordance with JIS-K-7121, using the following instrument under the following measurement conditions.

[0120] Name of Instrument: Robot DSC 6200 (available from Seiko Instruments Inc.)

[0121] Temperature Elevation. Rate: 10° C./min

(Amount of Residual Maleimide Monomer)

[0122] Each of the maleimide-based copolymer obtained as above (0.5 g) was dissolved in 1,2-dichloroethane solution containing undecane as internal standard (0.014 g/L, 5 ml). Subsequently, n-hexane (5 ml) was added to the solution and the mixture was shaken using a shaker for 10 to 15 minutes, thereby allowing insoluble matter (copolymer component) to precipitate. The supernatant was taken from the mixture while the insoluble matter was precipitated and settled, and injected into gas chromatograph. Quantitative value of the residual maleimide monomer was calculated from the peak area of the maleimide monomer, using the coefficient obtained. with the internal standard.

[0123] Name of Instrument: gas chromatograph GC-2010 (available from SHIMADZU CORPORNTION)

[0124] Column: capillary column DB-5 ms (available form Agilent Technologies Japan, Ltd.)

[0125] Temperature: inlet: 280° C., detector 280° C.

[0126] Programmed temperature gas chromatography was performed with column temperature (initial) of 80° C.

[0127] (conditions of programmed temperature gas chromatography)

[0128] 80° C.: held. for 12 minutes

[0129] 80 to 280° C.: temperature elevation by 20° C./min for 10 minutes 280° C.: held for 10 minutes Detector: FID

[0130] (yellowness (YI))

[0131] Yellowness was measured in accordance with JAS K-7373. Specific procedures were as follows.

[0132] Each of the maleimide-based copolymer obtained as above (1 g) was dissolved in tetrahydxofuran (25 mL). After dissolving the maleimide-based. copolymer, the solution was transferred into a square cell for measurement. Color difference was measured by transmission method with D65 light source of CIE standard. using a square cell containing tetrahydrofuran as a blank under the conditions of 23° C. temperature and 50% humidity. The value obtained was taken as the yellowness. Name of Instrument: SE7700 spectrophotometer (available from Nippon Denshoku Industries Co., Ltd.) Square Cell: A02277A. 10 a 36×55H square cell, two-side transmission

[0133] <Examples, Comparative Examples>

[0134] Examples 1 to 8, Comparative Examples 1 to 7 (kneading and mixing of maleimide-based copolymer and ABS resin)

[0135] Maleimide-based copolymers of A-1 to A-8 and commercially available ABS resin “GR-3000” (available from Denka Company Limited.) were blended by a ratio shown in Table 3 and Table 4. Subsequently, extrusion was performed using a twin-screw extruder (TEN-35B, available from TOSHIBA. MACHINE CO., LTD, currently SHIBAURA MACHINE CO., LTD.) to obtain pellets. These pellets were used. to prepare test specimens using an injection molding machine. Various physical properties of the test specimens were measured. Results are shown. in Table 3 and Table 4.

TABLE-US-00003 TABLE 3 Example Example Example Example Example Example Example Example 1 2 3 4 5 6 7 8 maleimide-based copolymer used — A-1 A-2 A-3 A-4 A-5 A-6 A-7 A-8 physical formulation GR-3000 mass % 80 80 80 80 80 80 80 80 property amount maleimide- mass % 20 20 20 20 20 20 20 20 evaluation based result copolymer Charpy impact kJ/m.sup.2 10.5 10.4 10.0 11.1 11.7 10.6 10.5 10.1 strength (with notch) Vicat softening ° C. 112 112 112 113 112 113 112 112 temperature (50N) MFR (220°, 98N) g/10 min 12 13 12 11 13 12 10 11 YI 40.1 48.2 32.5 48.9 40.2 40.2 47.5 44.8 chemical resistance B A B B B B A A

TABLE-US-00004 TABLE 4 Comparative Comparative Comparative Comparative Comparative Comparative Comparative Example1 Example2 Example3 Example4 Example5 Example6 Example7 maleimide-based copolymer used — B-1 B-2 B-3 B-4 B-5 B-6 B-7 physical formulation GR-3000 mass % 80 80 80 80 80 80 80 property amount maleimide- mass % 20 20 20 20 20 20 20 evaluation based result copolymer Charpy kJ/m.sup.2 11.7 13.3 14.4 16.7 18.1 19.9 3.1 impact strength (with notch) Vicat ° C. 112 113 112 113 113 114 113 softening temperature (50N) MFR (220°, g/10 min 9 9 9 9 9 7 11 98N) YI 54.7 55.4 52.9 77.7 55.0 54.8 40.1 chemical resistance B B B A B B C

(Charpy Impact Strength)

[0136] The Charpy impact strength. was measured using a notched specimen in. accordance with JIS K-7111. Edgewise was adopted as the striking direction, relative humidity was 50%, and atmospheric temperature was 23° C. Here, digital impact tester available from Toyo Seiki Seisaku-sho, Ltd. was used as the measuring instrument.

(Vicat Softening Temperature)

[0137] The Vicat softening temperature was measured in accordance with JIS K-7206. Here, Method 50 (load: 50N, temperature elevation rate: 50° C./hour) was used, and the test specimen having the size of 10 mm×10 mm and 4 mm thickness was used HDT & VSPT testing device available from Toyo Seiki Seisaku-sho, Ltd. was used as the measuring instrument.

(Melt Mass Flow Rate)

[0138] Melt mass flow rate was measured. in accordance with JIS K-7210, under the conditions of 220° C. and 98 N load.

Yellowness (YI)

[0139] Yellowness was measured in accordance with JTS K-7373. Speciflc procedures were as follows.

[0140] Each of the test specimens obtained as above (1 g) was dissolved in tetrahydrofuran (25 mL). After dissolving the specimen, the solution was transferred into a square cell for measurement. Color difference was measured by transmission method with D65 light source of CIE standard using a square cell containing tetrahydrofuran as a blank under the conditions of 23° C. temperature and 50% humidity. The value obtained was taken as the yellowness.

[0141] Name of Instrument: SE7700 spectrophotometer (available from Nippon Denshoku Industries Co., Ltd)

[0142] Square Cell: A02277A 10×∓×55H square cell, two-side transmission

(Chemical Resistance)

[0143] Cracks of a test specimen having a shape of 316×20×2 mm were observed after 48 hours at 23 C. by a quarter ellipse method having a major radius of 250 mm and a minor radius of 150 mm. In order to eliminate influence of molding strain, the test specimen was produced by pressing and. cutting out a pellet at 260° C. Toluene was used as the chemical.

[0144] Critical strain was obtained by the following equation.

ε=b/2a.sup.2[1−(a.sup.2−b.sup.2)X.sup.2/a.sup.4].sup.1.5×t×100

[0145] Critical strain: ε, major radius: a, minor radius: b, thickness of test specimen: t, crack initiation point: X

[0146] The chemical resistance was evaluated from the critical strain according to the following criteria.

[0147] A: 0.8 or more, B: 0.6 to 0.7, C: 0.3 to 0.5, D: 0.2 or less

[0148] As can be understood from Example 1 to Example 8, the maleimide-based copolymers A-1 to A-8 of the present inventions were able to achieve high mid-point glass transition temperature (Tmg) and high melt mass flow rate by decreasing the molecular weight without decreasing the content of the maleimide monomer unit in the composition. However, when the molecular weight was decreased to below a certain value, deterioration in chemical resistance was observed as in Comparative Example 7. The maleimide-based copolymers of B-1 to B-7, which do not satisfy the requirement of the present invention are out of the range of the Claims of the present invention. The resin compositions of Comparative Example 1 to Comparative Example 7 obtained by kneading and mixing such maleimide-based copolymer and ABS resin were inferior in at least impact resistance, flowability, or chemical resistance.

INDUSTRIAL APPLICABILITY

[0149] The maleimide-based copolymer of the present invention can provide a resin composition having superior balance in chemical resistance, heat resistance, impact resistance, and flowability, by kneading and mixing the maleimide-based copolymer with ABS resin, ASA resin, AES resin, or SAN resin which are compatible with the maleimide-based copolymer. The maleimide-based copolymer can also improve the flowability of mixed resin. Therefore, speed of molding can be enhanced, and production speed can be improved. Further, the maleimide-based copolymer can suppress yellowness (YI) of the molded article, and thus the molded article can be used for white products.