Patent GB-723558-A (GB)
Title: Terpolymers of acrylonitrile, 1-vinylimidazole and a third, different monomer containing the >c=c< linkage
IPC: C08F220/44
Filed: 1952-03-03
Abstract: Fibres are obtained by spinning solutions of terpolymers, derived from 50 to 97 per cent acrylonitrile, 1 to 18 per cent of a monomer containing a >C=C< group and at least 2 per cent of a 1-vinylimidazole, into a setting liquid which may be water or water with predetermined proportions of the spinning solvent. Spinning solvents specified are N,N-dimethylformamide, ethylene carbonate, \su-butyrolactone, a  - cyanoacetamide, N,N - dimethylacetamide and maleic anhydride.  Lists of 1-vinyl imidazoles, monomers and catalysts are given and the resulting terpolymer is usually of molecular weight between 15,000 and 300,000.  The terpolymers of 50 to 80 per cent acrylonitrile may be blended with other acrylonitrile polymers prior to spinning. The fibres are receptive to dyestuffs and the examples illustrate the dyeing with Wool Fast Scarlet of fibres spun from N,N-dimethylacetamide on to a water/N,N-dimethylacetamide coagulating mixture.  Specifications 682,180, [Group IV (a)], and 693,864 are referred to.ALSO:Terpolymers containing from 50 to 97 per cent acrylonitrile, at least 2 per cent of a 1-vinylimidazole and 1 to 18 per cent of a third monomer containing a >C=C< group may be prepared by any method such as bulk, solution or suspension polymerization wherein the ingredients may be added continuously, intermittently or batchwise.  The 1-vinylimidazoles that may be used are the parent compound and derivatives having groups of not more than 5 carbon atoms, e.g. 2-ethyl-, 2-methyl-, 4-ethyl-, 4-methyl-, 5-ethyl-, 5-methyl-, 2,4-diethyl-, 4,5-diethyl-, 2,5-diethyl-, 2,4-dimethyl-, 4,5-dimethyl-, 2,5-dimethyl-, 2-butyl- and 4-amyl-1-vinylimidazoles.  The third monomer may be vinyl acetate, propionate or butyrate; vinyl or vinylidene chloride or fluoride; allyl or methallyl alcohol, acetate, laurate or cyanide; methacrylic or ethacrylic acid; methyl, ethyl, propyl or butyl acrylate or methacrylate; acrylamide or methacrylamide; N-methyl, N-ethyl, N-propyl or N-butyl acrylamide or methacrylamide; methacrylonitrile or ethacrylonitrile; isobutylene or dimethyl, diethyl, dipropyl or dibutyl maleate, fumarate or citraconate. Catalysts specified are hydrogen and sodium peroxides, potassium persulphate, calcium percarbonate, azo - 2,21 - diisobutyronitrile, dimethyl-2,21 - azodiisobutyrate, 2,21-azobis (2,4-dimethylvaleronitrile), 2,21-azodiisobutyramide and diazoaminobenzene.  To obtain higher molecular weight terpolymers the redox method using compounds containing low-valent sulphur, e.g. sulphur dioxide, sodium bisulphite and sodium thiosulphate, may be used.  In emulsion polymerization dispersing agents specified are sodium stearate, alkali metal salts of sulphonated paraffins, sulphonated naphthalenes and sulphonated alkyl benzenes, sodium salts of formaldehyde condensed alkyl aryl sulphonic acids, triethanolamine and the alkali salts of sulphuric half-esters of fatty alcohols.  Molecular weight regulators such as t.-dodecyl mercaptan, thioglycollic acid, thiourea, mercaptobenzothiazole and carbon tetrachloride may be used. Terpolymers containing at least 80 per cent acrylonitrile may be dissolved in solvents such as N,N-dimethylformamide, ethylene carbonate, g  - butyrolactone, a -cyanoacetamide, N,N-dimethyl acetamide and maleic anhydride and then spun into a non-solvent for the copolymer such as water or water/solvent mixtures, e.g. water/N,N-dimethylacetamide.  The fibres obtained may be stretched and oriented.  Terpolymers containing less than 80 per cent acrylonitrile may be blended with acrylonitrile polymers to impart dyestuff receptivity.  The terpolymers are preferably of molecular weight between 15,000 and 300,000 and may be formed into fibres, yarns, films, foils and rods which may be readily dyed in a dyebath containing an acidic solution of Wool Fast Scarlet as illustrated in the examples.  Specifications 682,180 and 693,864 are referred to.