| 摘要 |
1,159,095. Preparation of dyeable acrylonitrile polymer fibres. JAPAN EXLAN CO. Ltd. 27 Oct., 1966 [27 Oct., 1965], No. 48324/66. Heading C3P. Acrylonitrile polymer fibres having whiteness stability and receptivity to disperse and cationic dyestuffs are prepared by treating an extruded fibre composed of a polymer or a polymer blend containing at least 80%, but less than 100%, by weight of acrylonitrile units and not more than 20%, but more than 0%, by weight of units of at least one other ethylenically unsaturated monomer of which one contains at least one dissociable acid group (e.g. -SO 3 H, -OSO 3 H or -COOH), with an aqueous solution of an alkali metal or ammonium salt of an inorganic acid, said solution having a pH of 2.0-4À0 and being used in such an amount that 75-95% of the dissociable hydrogen atoms of the extruded polymer are replaced by alkali metal atoms or ammonium groups. Fibres containing sulphonic acid groups may comprise units of an acid such as an alkenylarylsulphonic acid, vinyl-sulphonic acid, allyl sulphonic acid or methallylsulphonic acid. In addition to the acrylonitrile and acid units, the fibres may also contain other monomer units, e.g. alkyl acrylates or methacrylates, methacrylonitrile, vinyl or vinylidene chloride, acrylamide or methacrylamide, N-methylolacrylamide, methyl vinyl ketone, vinyl carboxylates, styrene and methylstyrenes. The fibres are preferably obtained by a wet-spinning technique from solutions of the polymer in concentrated aqueous thiocyanate. The pH of the aqueous salt solution used for treating the fibres is adjusted to the desired value by addition of an inorganic or organic acid. In an example, fibres of an acrylonitrile-ethyl acrylate-methallylsulphonic acid copolymer are treated with an aqueous solution containing nitric acid and sodium sulphate, and then dyed with p-aminobenzene (a disperse dye). |
