| 摘要 |
1505299 Laminated insulating and impactresistant plastics material MONSANTO CO 22 Dec 1975 [23 Dec 1974 (2)] 52324/75 Heading B5N A laminate comprises, in order, layers of (I) thermoplastic material, (2) rubber-modified nitrile polymer containing 55-85 wt. per cent nitrile units and 5-30 wt. per cent synthetic or natural rubber (the nitrile unit content excluding nitrile units in the rubber and being calculated as an equimolar weight of acrylonitrile), and (3) a cellular insulating material, the major amount of whose cells are filled with gaseous halogenated aliphatic or cycloaliphatic hydrocarbon. Insulating panels are made by bonding a further layer, e.g. steel, aluminium, wood, plastics or a laminate of (1) and (2) to the exposed surface of the foam (3) by foaming in situ, using a prelaminate of (1) and (2), or by laminating with adhesive or melt adhesion. The laters (1) and (2) may be of thickness 50- 750 and 0À5-20 mils respectively; may be laminated by heat and pressure, adhesive, extrusion of one or both layers, or application of a solution or dispersion of one material to the other; may be oriented; and may be vacuumformed to a desired shape. The layers (I) may comprise an impact-resistant ABS copolymer (including equivalent materials other than A, B, S), polyvinyl chloride, polycarbonate or polymethyl methacrylate, and the layer (3) may comprise polyurethane, in which the gaseous material is the residue of a blowing agent or is added for insulation. Suitable fluoro- and chlorofluoro-carbons are listed. The polymer (2) may be formed by direct polymerization and/or graft polymerization techniques, the nitrile polymer preferably being a copolymer with an olefinic comonomer; preferably the rubber is grafted in one or two stages with nitrile polymer and blended with further nitrile polymer. (The Specification gives detailed information as to materials and amounts.) The laminate may be used for thermally insulating refrigerator and cooling box panels, the panels being shaped to provide shelf supports and corrugated surfaces if desired, and for acoustic insulation and boat hulls. |
