Abstract: A polycarbonate having desirable color tone or transparency, as well as desirable heat resistance and water resistance, in which the amounts of residual metals in the polycarbonate are 10 ppm or less in total of Fe, Cr and Mo and 50 ppm or less in total of Ni and Cr. The polycarbonate is obtained by transesterification of (A) a dihydroxy compound and (B) a carbonic diester in a reactor made of a metallic material containing at least one metal selected from the group consisting of Fe, Cr, Mo, Ni and Cu, and controlling the water content in the reactor to 500 ppm or less.

Abstract: There is disclosed a process for producing a polycarbonate which comprises reacting, by the melt method, (A) a dihydroxy compound with (B) a carbonic diester having a chloride contempt derived from chloroformate group of not more than a prescribed level. According to the above process, a polycarbonate which is excellent in transparency, tone of color, heat resistance and water resistance can be efficiently and economically produced.

Abstract: Disclosed herein is a polycarbonate copolymer comprising repeating units respectively made of a bisphenol A and a tetrahalogenobisphenol A and having a trihalogenophenoxy group as an end group at the terminal, particularly both terminals thereof and a method for efficiently producing said polycarbonate copolymer. This polycarbonate copolymer is superior in impact resistance, flame retardance, molding thermostability and the like, is good in hydrolytic resistance, is much less liable to cause a mold rust and has high quality. Therefore, this polycarbonate copolymer will be extensively used in various industrial materials, for example as the flame retardant parts for household electric appliances, office automation apparatuses and the like.

Abstract: A process for producing a styrenic polymer suitable for making molded products which has excellent quality without a decrease in the productivity. The process comprises feeding a compound consisting essentially of a styrenic monomer to 2 to 6 units of reactors connected in series and carrying out a bulk polymerization at a reaction temperature of 90.degree. to 200.degree. C. and a difference of reaction temperatures among the units of reactors of not more than 40.degree. C. and in the presence of 10 to 450 ppm by weight of an organic peroxide represented by the following formula (I): ##STR1## wherein R represents a tertiary alkyl group or a tertiary aralkyl group, and R.sup.1 and R.sup.2 each represent an alkyl group having 1 to 2 carbon atoms, the styrenic polymer having a weight average molecular weight of 30.times.10.sup.4 to 70.times.10.sup.4 and a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn of not more than 3.0.

Abstract: The thermoplastic resin composition of the invention comprises (A) from 50 to 90 parts by weight of a copolymer of an aromatic vinyl monomer and an unsaturated dicarboxylic acid anhydride, e.g. copolymer of styrene and maleic anhydride, (B) from 50 to 10 parts by weight of an ABS or MBS resin and (C) from 0.01 to 1.0 part by weight of an organopolysiloxane. In contrast to conventional polymer blend compositions composed of the above mentioned components (A) and (B), the inventive resin composition is capable of giving a shaped article having a greatly improved impact strength without adverse influences on the heat resistance and surface luster of the shaped articles molded of a resin composition of this type inherent thereto.