| 摘要 |
1,087,531. Voided olefin copolymer films and fibres. IMPERIAL CHEMICAL INDUSTRIES Ltd. July 6, 1966 [July 14, 1965], No. 29821/65. Heading B5B. An oriented, voided film or fibre is made, by extrusion, from a copolymer composition which is the homogeneous product of a polymerization process in which from 75-95% of an aliphatic define monomer and from 5-25% of either a second olefin monomer or a blend of such monomers are brought into contact with a stereospecific catalyst to cause their polymerization either in rotation (this term is defined) or sequentially, quenching the extrudate, and drawing it under conditions of temperature, draw-ratio and draw-rate such that it draws through a neck. Specified olefines are ethylene, propylene, butene-1, 3-methyl butene-1 and 4-methyl pentene-1. Suitable temperatures are from 15‹ C. above room temp., with a draw ratio of 3: 1 to 10:1 at a draw rate of 200-300,000% per minute. The products may be heat-set, e.g. at 140‹ C. The copolymer compositions are prepared, e.g. according to Specifications 970,478 and 1,014,944. |
