| 摘要 |
Acrylonitrile is polymerized alone or together with a minor proportion of one or more ethylenically unsaturated monomers, in the presence of a material which is a plasticizer for the polymer to be formed, such as ethylene carbonate, tetramethylene cyclic sulphone, N-acetyl morpholine, dimethyl formamide, lactones, or lactams, the mixture being emulsified in an inert liquid medium which is a non-solvent for the polymer and which is immiscible or difficulty miscible with the plasticizer, such as the isomeric hexanes, heptanes, and octanes, cyclopentane, cyclohexane, methyl cyclohexane, mono- and di-fluoro pentanes, hexanes, and heptanes, perfluorohexane, perfluorocyclohexane, and perfluorododecane. Ethylenically unsaturated monomers which may also be present are 2-vinylpyridine, 5-ethyl-2-vinylpyridine, 5-vinyl-2-methylpyridine, esters of acrylic and methacrylic acids, styrene, methyl vinyl ketone, and vinyl or vinylidene halides. Polymerization may be carried out with the aid of catalysts such as benzoyl peroxide, lauryl peroxide, diethyl peroxide, alpha, alpha1-azobis (alpha, gammadimethylvaleronitrile), azobis-dimethylvaleronitrile, and alpha, alpha1-azobis (alpha, gammadimethyl-gamma-methoxyvaleronitrile); the polymerization mixture may also contain starch or "Alkanol" WXN. The polymerization product is an intimate mixture of polymer and plasticizer in the form of granules which preferably have a solids content of 35-60 per cent., and which may be melt spun into yarns and films.
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