POLYMER PARTICLES AND PROCESS FOR PRODUCTION THEREOF

摘要

Polymer particles and a process for the production thereof are provided by which the problem of formation of too small particles in suspension polymerization process, the problem of too large energy consumption for drying in emulsion polymerization process, and the problems of blending significant to processors can be solved at a stroke. The process comprises coating 100 parts by weight of polymer particles produced by suspension polymerization and having a mean particle diameter of 50 to 500mum with 22 to 100 parts by weight of an emulsion polymer produced by emulsion polymerization. In particular, the process comprises mixing a polymer suspension produced by suspension polymerization and having a mean particle diameter of 50 to 500mum with a polymer latex produced by emulsion polymerization at a ratio of the emulsion polymer to the suspension polymer ranging from 22 : 100 to 100 : 100, adjusting the solid polymer content of the obtained mixed suspension to 25 to 35 wt%, bringing the resulting suspension into contact with an aqueous electrolyte solution at a temperature not higher than the Vicat softening point of the emulsion polymer, heating the resulting system to a temperature not lower than the Vicat softening point of the emulsion polymer, and recovering polymer particles by solid-liquid separation.