GB1210656A - Improvements in or relating to polyurethane foam materials - Google Patents

Abstract

1,210,656. Coated foams. DUNLOP CO. Ltd. 6 June, 1968 [7 June, 1967], No. 26256/ 67. Heading B2E. [Also in Divsion C3] A composite polyurethane foam material is produced by impregnating an open-cell polyurethane foam with a monomer or monomers selected from olefinically-unsaturated hydrocarbon monomers, halogen derivatives thereof, and acrylonitrile, and polymerising the monomer(s) within the foam to form a deposit of polymer within the pores of the foam. The foam may be a skeletal or reticulated foam. The polymerisation may be carried out by an irradiation technique, an emulsion polymerisation technique, or in the presence of a peroxide catalyst. The composite material may be subsequently compressed and a further monomer may be graft polymerised on to the polymer deposit within the pores of the foam. The hydrocarbon monomers may be ethylene, propylene, butene-1 and 'butene-2; butadiene; pentadienes and styrene; halogen derivatives, e.g. vinyl chloride; and mixtures thereof. The monomer(s) may be used in liquid or gaseous state. In Example I, the foam is enclosed in a chamber, a mixture of hydrogen and oxygen introduced to a final absolute pressure of 0.8 atmosphere and, the mixture ignited by means of a sparking plug; the foam is subsequently placed in gaseous butadiene and subjected to high energy ionising radiation. Example 2 describes foam immersed in acrylonitrile, drained and irradiated; and also foam irradiated while immersed in a solution of acrylonitrile in benzene. Example 3 describes foam immersed in styrene, drained and irradiated; and also foam irradiated while immersed in a solution of styrene in cyclohexanone.