Abstract: The invention relates to a liquid isocyanate-containing prepolymer composition having an average isocyanate functionality greater than 2 and an NCO content of from 2 to 15% by weight, as obtainable by reacting an isocyanate reactive polymer having an average nominal functionality of from 2 to 6 with a stoichiometric excess of a diphenylmethane diisocyanate composition containing at least 2% by weight of 2,4'-diphenylmethane diisocyanate and having an average isocyanate functionality in the range from 2 to 2.3. The invention also relates to a method for preparing a polyurethane foam, which comprises reacting such a prepolymer composition with water.

Abstract: Polyol compositions containing siloxane mould release agents, the latter being stabilized by a poly (ethyleneoxide) surfactant, useful in RIM processing of polyurethanes.

Abstract: Liquid polyisocyanate compositions comprising:(A) from 90 to 50% by weight of a reaction product of diphenylmethane diisocyanate and a polyoxyalkylene polyol having an average functionality of 2-3 comprising from 50-100% by weight of a polyoxypropylene diol or triol having a hydroxyl equivalent weight of from 750 to 3000 and from 0-50% by weight of a polyoxyethylene diol or triol having a hydroxyl equivalent weight of from 750 to 3000, said reaction product having an NCO content of from 8 to 26% by weight, and(B) from 10 to 50% by weight of a diphenylmethane diisocyanate composition containing from 30 to 65% by weight of diphenylmethane diisocyanate, the remainder being polymethylene polyphenyl polyisocyanates of functionality greater than two together with by-products formed in the manufacture of such polyisocyanates by phosgenation.The compositions are useful in the manufacture of polyurethanes, especially cold cure flexible foams.