Polyacrylonitrile threads for carbon fibre prodn - by polymsg acrylonitrile in zinc chloride-sodium chloride soln., and spinning-drawing

摘要

Polyacrylonitrile fibres and threads for prodn. of carbon and graphite fibres are prepd. by (a) dissolving acrylonitrile and a comonomer in a highly conc. aqs. soln. of zinc chloride and sodium chloride, (b) polymerising in the presence of formaldehyde and hydrogen peroxide, under the action of 1.v. light, (c) immediately spinning the soln. into a coagulation bath, and (d) drawing during coagulation so that an oriented structure is formed in the membrane at the surface of the thread. The fibres have very high strength e.g. 12-15 g/denier and give high strength carbon and graphite fibres. The draw ratio is pref. 1/3-4. The aqs. soln. pref. also contains copper iron and manganese ions. The aqs. spinning soln. pref. contains 38-40 wt. % zinc chloride, 18-20 wt. % sodium chloride, 40-60 mg/1 manganese ions and 4-6 mg/1 iron ions.