| abstract |
A polyvinyl alcohol having 1,2-glycol bonds in side chains. It has the following and other features. During the production thereof, dimethyl carbonate or the like is not generated. The step of recovery from the waste liquid resulting from saponification does not necessitate a step for dimethyl carbonate removal. Even when 1,2-glycol bonds are incorporated in an increased amount, the copolymer (paste) before saponification has intact solubility in a saponification solution (methanol). The polyvinyl alcohol suffers no decrease in water solubility even after it has undergone a heat history. The polyvinyl alcohol having 1,2-glycol bonds in side chains is obtained by saponifying a copolymer of a vinyl ester monomer with a compound represented by the formula (1). |