GB795335A - Preparation of elastomeric cellular materials - Google Patents

Abstract

In the preparation of an elastomeric cellular material by reacting a polymeric material containing a plurality of active hydrogen atoms, a polyisocyanate and water, from 0.002 to 0.02 per cent of a silicone oil is added to the reaction mixture. When cushions are made from this material there is thus less movement of the upper part of the cushion parallel to the lower part when a horizontal force is applied. The polymeric material may be a linear or branched polyester or polyesteramide or a polyalkylene ether glycol. The polyisocyanate may be p-phenylene, m-phenylene, 1.5-naphthalene, 4.41-diphenylenemethane, tolyene or hexamethylene diisocyanate. The silicone oil has the formula: <FORM:0795335/IV (a)/1> wherein R is an organic hydrocarbon radical (e.g. methyl or ethyl). In Examples (2)-(5), to a prepolymer made by heating a polyester derived from adipic acid, ethylene glycol, diethylene glycol and 1.4-butanediol with tolylene diisocyanate there was added first tolylenediisocyanate and castor oil, then an activator mixture comprising the above polyester, water, N-methylmorpholine an alkylated aryl polyether alcohol (as emulsifier) and a condensate of 4 mols. of butyraldehyde and 1 mol. of aniline, and finally a silicone oil; the complete reaction mixture was then poured into a mould where it was permitted to expand and cure and was then heated to complete the cure; (7), (8) and (9), similar to Examples 2-5, except that the prepolymer is prepared by heating a mixture of the polyester, the tolylene diisocyanate and 1.4-butane diol.