PRODUCTION OF VINYL CHLORIDE POLYMER

• Main Authors: MURASE YASUO, MORIMOTO TADASHI, SHIBATA JUNZO, MAKINO TETSUYA
• Format: Patent
• Language: English
• Published: 13.11.1987
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PURPOSE:To obtain the title polymer of a high bulk density, by suspension- polymerizing a vinyl chloride monomer in an aqueous medium in the presence of a combination of two specified water-soluble partially saponified polyvinyl acetates differing in a degree of saponification, etc. as a dispersant. CONSTITUTION:A dispersant is prepared by mixing a water-soluble partially saponified polyvinyl acetate (A) having a degree of saponification of 85-90mol% and a viscosity of 25-65cP as measured in its 4% aqueous concentration at 20 deg.C with a water-soluble partially saponified polyvinyl acetate (B) having a degree of saponification of 65-75mol% and a viscosity of 5-6cP as measured in its 4% aqueous solution at 20 deg.C at a component A to component B weight ratio of 3/1-1/3. The purpose vinyl chloride polymer is obtained by suspension- polymerizing a vinyl chloride monomer or a mixture containing a major proportion of a vinyl chloride monomer and a copolymerizable monomer in an aqueous medium in the presence of the above dispersant.