| 摘要 |
<p>The absorption of water by styrene/maleic anhydride copolymer particles during the impregnation of the particles with hydrocarbon blowing agent in aqueous suspension is greatly reduced by the addition of salt to the impregnation system.</p><p>This process produces expandable particles of non-equimolar copolymers of styrene and maleic anhydride having considerably less heterogeneity, finer cell structure, greater expandability, less heat sensitivity, less shrinkage, and lower density potential on molding.</p> |
