| 摘要 |
The Specification refers to b -hydroxyethyl and b -hydroxypropyl ethers and mixed ethers of polyvinyl alcohol. In the examples, b -hydroxyethyl vinyl ether and vinyl acetate are copolymerized in t-butyl alcohol using azobisisobutyronitrile catalyst. The copolymer produced is then hydrolysed by refluxing with sodium methoxide in methanol. In Example III, b -hydroxyethyl vinyl ether is polymerized in t-butyl alcohol with azobis-isobutyronitrile catalyst. Specifications 592,676, 600,058, 658,588, 658,826, 718,422, 786,176, 853,588, French Specification 708,236 and U.S.A. Specification 1,925 508 are referred to. |
