| 摘要 |
Fibres or foils are produced by mixing "A" and "B" polymers, dissolving the mixture in a common solvent and subjecting the solution to a wet or dry spinning or extrusion process, the "A" polymer being polyvinyl chloride or a copolymer predominating (by weight) in vinyl chloride and the "B" polymer consisting of or predominating in units -CH2-CR1R2-, where R1 is H or CH3 and R2 is a carbocyclic or substituted carbocyclic radical, having a second order transistion temperature above 100 DEG C. and a softening temperature above 150 DEG C., and being water-resistant. The mixture may include a compatible plasticizer. Specified comonomer for "A" are monomers containing sulphonic or carboxyl groups to improve dye affinity, e.g. maleic anhydride and acrylonitrile, vinyl acetate and acrylic esters or their alpha-substituted derivatives. Extensive examples of "B" polymers include polymers of alpha- or ring mono- or polyalkyl, halo, hydroxy, alkoxy or carboxyl substituted styrenes and copolymers of styrene with alpha-methyl styrene or acenaphthalene. Examples of solvents include cyclic ethers, aliphatic and cyclic ketones, halohydrocarbons and mixtures thereof with benzene or methanol. In examples the solution is extruded through a spinneret into air, water, or aqueous sodium sulphate, dioxane or tetrahydrofuran and the resulting fibres subjected to various of the following treatments; winding-up, stretching in air, hot water or solvents, heat-stretching between hot rollers, shrinking or crimping. In Example 14 the solution is extruded through a slit into aqueous tetrahydrofuran to give a film.
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