| 摘要 |
<p>The invention relates to processes of obtainment of polyvinilalcohol (PVAL) modified by unsaturated carboxylic acids and can be applied in textile, film an fiber industries, medicine, cosmetics in other fields.Vinylacetate is subjected to radical copolymerization with derivative of maleic acid - maleic anhydride in methanol and obtained copolymers are then subjected to basic alcoholises. The mixture of maleic anhydride with methanol is put into the reaction system in one step, at any period of time from the moment of mixing until complete transformation of maleic acid into ester of maleic acid or immediate by without preliminarily dissolving it in methanol.Polyvinyl alcohol is obtained with different functional composition and correspondingly, with different properties.</p> |
