| 摘要 |
<p>A method of separating polyvinyl butyral from admixture with plasticizer comprises intimately mixing the polyvinyl butyral with a volatile liquid in which the plasticizer is substantially more soluble than is the polyvinyl butyral and separating the liquid phase from the polyvinyl butyral. The liquid may be a non-solvent for the polyvinyl butyral e.g. an aliphatic or cycloaliphatic hydrocarbon, or a swelling solvent, e.g. an aromatic hydrocarbon, 1,1,1 - trichloroethane, carbon tetrachloride, ethylene dichloride, acetone, diisobutyl ketone, acetonyl acetone, ethyl acetate, isopropyl acetate, amyl acetate or nitropropane, or a mixture of the two. The liquid may be a partial solvent, e.g. chloroform, trichloroethylene, propylene dichloride, methyl ethyl ketone, methyl-isobutyl ketone, cyclohexanone, butyl acetate or 2-amino-2methyl-1-propanol or a mixture of a partial solvent and a non-solvent.</p> |
