| 摘要 |
A vinyl chloride polymer having an excellent workability, lubricating property, and gelling property comprises (1) from 80 to 99.95 weight % of a polymeric ingredient (I) consisting of polyvinyl chloride and/or a copolymer of 80 weight % or more of vinyl chloride with 20 weight % or less of another comonomer and (2) from 0.05 to 20 weight % of a polymeric ingredient (II) consisting of at least one three-stage emulsion polymerization product prepared by first polymerizing, in the presence of a polymeric component (a) consisting of polymethyl methacrylate and/or a copolymer of 50 weight % or more of methyl methacrylate and 50 weight % or less of another comonomer, from 40 to 70 parts by weight of a first monomeric component (b) consisting of an alkyl acrylate (C1-18) and/or benzyl acrylate or a mixture of 30 weight % or more of an alkyl acrylate (C1-18) and/or benzyl acrylate with 70 weight % or less of an alkyl methacrylate (C1-18) and/or benzyl methacrylate under such a polymerization condition that when the monomeric componet (b) alone is polymerized, the resultant product exhibits a reduced viscosity of 1 or less in a concentration of 0.1 g/100 ml of chloroform of 25 DEG C. and by second polymerizing, in the presence of the first polymerization product, from 5 to 40 parts by weight of a second monomeric component (c) consisting of methyl methacrylate or a mixture of 50 weight % or more of methyl methacrylate and 50 weight % or less of another comonomer, the sum of the components (a), (b), and (c) being 100 parts by weight and the preparation of the polymeric component (a) and the first and second polymerizations being carried out by means of an emulsion polymerization method in the presence of a chain transfer agent. |
