| 摘要 |
<p>1516047 Laminated films W R GRACE & CO 21 May 1976 [22 May 1975] 21198/76 Heading B5N A polymeric laminated film comprising at least two cross-linked polymeric layers, one of which is cross-linked to a greater extent than the other may be made by irradiating a laminate film comprising at least a layer (1) of a polymer which has undergone cross-linking and (2) a layer of an irradiation cross-linkable polymer. A preferred film comprises at least two crosslinked alpha-monoolefin polymer layers, at least one such layer, e.g. of polyethylene or ethylenevinyl acetate copolymer being cross-linked to a greater extent than any other, and, intermediate two such layers a barrier layer of a vinylidene chloride polymer or an ethylenevinyl alcohol copolymer, the lesser cross-linked layer being preferably a blend of polybutene-1 with an ethylene-propylene copolymer. Extrusion techniques may be used on the formation of the film which may be tubular and may also be stretched.</p> |
