Abstract: The invention relates to a method of making branched polysiloxane-polyoxyalkylene copolymers and to their use as stabilizers in the production of polyurethane foam plastics. The copolymers are made by reacting specified organopolysiloxanes with polyisocyanates, heat treating the NCO-containing addition products to cause branching and reacting the branched NCO-containing addition products with monofunctional polyethers. The copolymers can be used to stabilize polyurethane foam reaction mixtures.

Abstract: The instant invention is directed to stable dispersions and the process of their manufacture. The stable dispersions of the instant invention comprise polyureas and/or polyhydrazo-dicarbonamides as the disperse phase in an hydroxyl group containing material selected from the group consisting of polyethers, polyesters, polyester amides, polycarbonates, and mixtures thereof, and are produced by reacting (1) organic polyisocyanates with (2) polyamines containing primary and/or secondary amino groups and/or hydrazines and/or hydrazides in (3) the hydroxyl group containing material. Component (3) may also contain relatively low molecular weight polyols and/or inert organic solvents. Components (1), (2) and (3) are continuously introduced into a flow mixer in such a quantity that the average residence time in the mixer is less than ten minutes.