| 摘要 |
Fibres, films and other shaped articles are obtained by extruding a solution of a polymer or copolymer of acrylonitrile containing also a cyanoethyl ether of cellulose into a coagulating medium, employing the wet- or dry-spinning technique. Inclusion of the cellulose ether increases the water absorption and also the decomposition temperature of the polyacrylonitrile article. The solution employing, for example, dimethyl formamide, dimethyl acetamide, tetrahydropyran, tetrahydrofuran, morpholine, ethylene carbonate, an organophosphonate or a sulphone, as the solvent, may be extruded at 25-150 DEG C. into hot air or other inert gas or into water, aqueous ammonium chloride or sodium thiocyanate, triethanolamine, ethylene glycol, glycerine, dilute sulphuric acid or an aqueous solution of the spinning solvent, at 25-150 DEG C. The articles may be washed and stretched in secondary baths or in steam and heat-treated at 100-180 DEG C. in the relaxed condition. Copolymers of acrylonitrile with vinyl acetate, styrene, vinyl chloride, the vinyl pyridines, isobutyne, dimethyl fumarate, methyl methacrylate, methacrylonitrile and acrylic acid and its esters may be employed. The cyanoethyl ether of cellulose is preferably prepared from viscose rayon by soaking the rayon in aqueous caustic soda, refluxing the alkali cellulose so obtained with acrylonitrile, neutralizing with acetic acid, cooling and finally adding methanol to precipitate the ether.
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