Patent GB-608078-A (GB)
Title: A process for the manufacture of threads, fibres, ribbons, films and the like
IPC: D01F6/24
Filed: 1946-02-14
Abstract: Threads, fibres, ribbons, films and like articles are produced by extruding solutions of compounds of average molecular weight of at least 5000, which compounds are polymeric and contain a plurality of unsaturated carbon-to-carbon linkages, through spining nozzles, the cross-section of which corresponds to the crosssection of the desired article, into solutions of inorganic acids or acid anhydrides among which acids and anhydrides those in which the acidforming elements are present in the highest valency are excepted, wherein the solvent for the polymeric compound is immiscible or practically immiscible with the solvent for the acid or anhydride.  Polymeric substances specified inter alia are polymers of butadiene, methyl and dimethyl butadienes, pentadiene and chloroprene, and copolymers of mixtures of these, polymers of acetylene and of derivatives thereof, and copolymers of the aforesaid dienes with isobutene, styrene, vinyl chloride, vinyl acetate, acrylic acid, methacrylic acid, acrolein, methyl isopropenyl ketone and vinyl ethyl ether.  Acids and acid anhydrides specified are sulphur dioxide, phosphorus trioxide, nitrous anhydride and acids from these, hydrogen sulphide, bromide and chloride or mixtures of these.  If the acids or anhydrides are dissolved in water, the polymeric substance may be dissolved in benzene, toluene, xylene, tetrahydronaphthalene, decahydronaphthalene, diisopropyl ether and mixtures of these. If the reaction is carried out at low temperatures, an easily soluble inorganic salt such as sodium, magnesium or calcium chloride may be added.  The reaction is accelerated by adding tetrahydronaphthalene dioxide to the solution of the polymeric substance.  Plasticisers, fillers and dyes may be added. Specification 527,075 is referred to.ALSO:Threads, fibres, ribbons, films and like articles are produced by extruding solutions of compounds of average molecular weight of at least 5,000, which compounds are polymeric and contain a plurality of unsaturated carbon to carbon linkages, through spinning nozzles of the required cross-section, into solutions of inorganic acids or acid anhydrides among which acids and anhydrides those in which the acid forming elements are present in the highest valuency are excepted, wherein the solvent for the polymeric compound is substantially immiscible with the solvent for the acid or anhydride. Among the polymeric substances specified are natural rubber, gutta percha, gutta balata and many polymers and copolymers of diolefins. Acids and anhydrides specified are sulphur dioxide, phosphorus trioxide, nitrous anhydride and acids from these, hydrogen sulphide, bromide and chloride and mixtures of these.  If the acid solvent is water the polymeric substance may be dissolved in benzene, toluene, xylene, tetrahydronaphthalene, decahydronaphthalene, disopropyl ether or mixtures of these.  If the reaction is carried out at low temperatures a salt such as sodium, magnesium or calcium chloride may be added.  Tetrahydronaphthalene peroxide may be added to the solution of the polymeric substance to accelerate the reaction with the acid or acid anhydride.  Plasticizers, fillers and dyes may be present.  Specification 527,075 is referred to.