Abstract: A thermoplastic resin composition obtained by melt-mixing:(a) 4 to 95% by weight of a polyphenylene ether resin,(b) 4 to 95% by weight of a polyamide,(c) 1 to 50% by weight of a rubbery polymer, and(d) if necessary, 91% by weight or less of a styrene resin (d)[the sum of the (a), (b), (c) and (d) components is 100% by weight] in the presence of 0.001 to 10% by weight, based on the total weight of the (a), (b), (c) and (d) components, of at least one functional group-containing unsaturated compound having at least one group selected from the class consisting of carboxyl group, acid anhydride group, epoxy group, hydroxyl group, amino group and amido group and 0.001 to 5% by weight, based on the total weight of the (a), (b), (c) and (d) components, of a peroxide. This thermoplastic resin composition is excellent in balance of impact strength of thin molded product, moldability and heat resistance.

Abstract: A heat-resistant copolymer obtained by copolymerizing (A) 72-82 parts by weight of .alpha.-methylstyrene and (B) 26-18 parts by weight of acrylonitrile, characterized in that the copolymer contains (a) 0-15% by weight of monomer chain 13 (A)-(A)-(A)--, (b) 50% by weight or more of monomer chain --(A)-(A)-(B)--, and (c) 50% by weight or less of monomer chain --(B)-(A)-(B)--, the total of (a), (b) and (c) being 100% by weight. This copolymer is excellent in heat stability and moldability when molded at high temperatures, and the blending of this copolymer with other thermoplastic resins gives thermoplastic resins with excellent heat resistance.

Abstract: A heat resistant thermoplastic resin composition comprising (a) 5 to 99% by weight of a poly(phenylene ether), (b) 95 to 1% by weight of a thermoplastic resin which is obtained by polymerizing in the absence of a rubber-like polymer a resin constituent mixture comprising an aromatic alkenyl compound, an alkenyl cyanide compound, and, if necessary, other alkenyl monomers copolymerizable with said monomers, and (c) up to 94% by weight of other styrenic resins, said thermoplastic resin (b) comprising (A) 1-50% by weight of a polymer having an alkenyl cyanide compound content of 1% by weight or more but less than 10% by weight, (B) 1-70% by weight of a polymer having an alkenyl cyanide compound content of 10% by weight or more but less than 20% by weight, (C) 5-90% by weight of a polymer having an alkenyl cyanide compound content of 20% by weight or more but less than 40% by weight, and (D) up to 70% by weight of a polymer having an alkenyl cyanide compound content of 40% by weight or more, and having a total alk

Abstract: A heat-resistant copolymer obtained by copolymerizing (A) 72-82 parts by weight of .alpha.-methylstyrene and (B) 26-18 parts by weight of acrylonitrile, characterized in that the copolymer contains (a) 0-15% by weight of monomer chain --(A)--(A)--(A)--, (b) 50% by weight or more of monomer chain --(A)--(A)--(B)--, and (c) 50% by weight or less of monomer chain--(B)--(A)--(B)--, the total of (a), (b) and (c) being 100% by weight. This copolymer is excellent in heat stability and moldability when molded at high temperatures, and the blending of this copolymer with other thermoplastic resins gives thermoplastic resins with excellent heat resistance.

Abstract: A thermoplastic resin having an excellent thermal stability and a high heat resistance is prepared by initiating polymerization of 65-85 parts by weight of a monomer mixture (A) consisting of 50-85% by weight of .alpha.-methylstyrene, 3-20% by weight of methyl methacrylate, 2-20% by weight of acrylonitrile, and 0-25% by weight of an aromatic alkenyl compound other than .alpha.-methylstyrene, continuously or intermittently adding, on the way of the polymerization, 2-15 parts by weight of a monomer (B) consisting of acrylonitrile or a mixture thereof with an aromatic alkenyl compound other than .alpha.-methylstyrene to the polymerization system while continuing the polymerization, further adding to the polymerization system 5-25 parts by weight of a monomer (C) consisting of an aromatic alkenyl compound other than .alpha.

Abstract: A process for producing a resin having a high heat resistance with a high polymerization conversion by emulsion-polymerizing .alpha.-methylstyrene (AMS), methyl methacrylate (MMA) and acrylonitrile (AN), characterized in that the polymerization is conducted in two steps; A monomer mixture consisting of 60-85% by weight of AMS, 2-30% by weight of MMA and 5-20% by weight of AN is subjected to copolymerization in the first step until 25-85% by weight, based on the weight of the final copolymer, of a copolymer is formed, and in the second step, at least one monomer of the above three monomers is added to the polymerization system to adjust the composition ratio of the three monomers in the polymerization system so as to fall in the region surrounded by the lines connecting points A, B, C, D and E in the triangular coordinate graph indicating the quantitative relationship of the three monomers, and the resulting monomer mixture is subjected to polymerization conditions to complete the polymerization.