| 摘要 |
PURPOSE:To make it possible to prevent a saponified and grafted olefin/vinyl ester copolymer from undergoing thermal change and becoming colored, by allowing an organic peroxide to act after the completion of the saponification reaction in the manufacture of the saponified and grafted olefin/vinyl ester copolymer. CONSTITUTION:An alpha-olefin/vinyl ester copolymer containing 10-50wt.% vinyl ester is saponified in a system containing a hydrocarbon solvent, a low boiling point alcohol and an alkali catalyst at ordinary temperatures-80 deg.C, and water is added to the saponified reaction mixture to deactivate the residual catalyst. An organic peroxide (e.g., a hydroperoxide, a dialkyl peroxide, etc. can be suitably used) in an amount of 0.05-1.0pt.wt. per pt.wt. saponified copolymer is allowed to act on the reaction mixture, and after or during the decomposition of the organic peroxide under heating, the low boiling point solvents are distilled off. Then, an ethylenically unsaturated carboxylic acid or its anhydride and a radical initiator are added to the reaction mixture to effect grafting, and finally the saponified and grafted copolymer is separated from the reaction mixture as a precipitate. |
