| 摘要 |
<p>The film, with tensile strength >=5 kg./mm.2, in which the main component layers have been strongly oriented, has >=1 layer consisting of a resin, which can be cold-drawn, which is (1) B + A + C, (2) B + A, (3) B + C, (4) D, or (5) E, where: A is an ethylene copolymer, e.g. with a vinyl ester, an aliphatic unsatd. carboxylic acid or an alkyl ester of such an acid, an ionically crosslinked resin derived from these copolymers, or a low-densith ethylene polymer; (B is a soft copolymer elastomer with Vicat softening point (VS) =60 degrees C.; C is crystalline polypropylene, high density polyethylene, crystalline polybutene-1 and/or polymethylpentene-1; D is a crystalline polybutene-1 with a concn. of 50-100 wt.%; and E is an ionically crosslinked resin. The film can be used for various purposes, esp. for shrink-packaging of foods. The film has improved impact strength, flexibility, optical and surface properties, and shrinkage porperties. It resists heat and cold, and can be melt-welded.</p> |
