Verfahren zur Herstellung von Polyvinylalkohol mit hohem Polymerisationsgrad

摘要

A process for preparing a substantially particulate polyvinyl alcohol having a high degree of polymerization of which a 4% by weight aqueous solution has a viscosity at 20 DEG C. of not less than 80 cps, which comprises hydrolyzing a substantially particulate polyvinyl ester having a high degree of polymerization in an alcohol containing an alkali catalyst in heterogeneous system. According to the process of the present invention, there can be easily produced a substantially particulate polyvinyl alcohol having high degree of polymerization, which has the high bulk density and the excellent powder flowability.