| 摘要 |
An ion exchange polymer comprises a sulphonated linear or cross-linked polymer of a , b , b -trifluorostyrene <FORM:1096879/C3/1> the linear polymer having a molecular weight of 13,500-400,000. The sulphonic acid radicals may be meta to the trifluoro-ethyl group and the polymer may be prepared by dissolving the polya , b , b -trifluorostyrene in chloroform in a concentration of 0.1-0.3 moles/1., adding a sulphonating agent, e.g. chlorosulphonic acid or oleum, in chloroform or perchloroethylene, in a concentration of 0.14 molecules/polymer phenyl group -3 moles/1. of solution at a temperature of 15-60 DEG C. for at least 10 minutes; cross-linking of the polymer occurs when the sulphonating agents concentration is at least 2 molecules/polymer phenyl groups. The sulphonated polymer may be compounded with polyvinylidene fluoride or chloride, a copolymer of vinylidene fluoride or tetrafluoroethylene and hexafluoro-propylene or chlorotrifluoroethylene, polyvinyl chloride, polyethylene, polyvinyl acetate, neoprene rubber, polyacrylonitrile, styrene-butadiene copolymer rubber, chlorosulphonated polyethylene or polychlorotrifluorethylene, together with water or acetone, tetrahydrofuran, dimethyl formamide or dioxan and triethylphosphate. The compositions may be used to form ion exchange membranes. |
