METHOD FOR PRODUCING POLYVINYL ALCOHOL HAVING SUFFICIENT MOLECULAR WEIGHT-REGULATED SYNDIOTACTICITY

摘要

PROBLEM TO BE SOLVED: To produce a polyvinyl ester-based polymer having a regulated molecular weight distribution from a vinyl ester-based monomer and a polyvinyl alcohol having the regulated molecular weight distribution and sufficient syndiotacticity by saponifying the polyvinyl ester-based polymer. SOLUTION: The polyvinyl ester-based polymer having 1.05-1.5 molecular weight distribution [weight average molecular weight (Mw)/number average molecular weight (Mn)] and≥54% syndiotacticity (doublet) by polymerizing the vinyl ester-based monomer in the presence of an iodine compound in a fluorine-containing branched alcohol having≥4 to <10 pKa. The polyvinyl alcohol having 1.05-1.5 molecular weight distribution [weight average molecular weight (Mw)/number average molecular weight (Mn)] and≥54% syndiotacticity (doublet) is produced y saponifying the polyvinyl ester-based polymer. COPYRIGHT: (C)2006,JPO&NCIPI