Process for the production of polysiloxane ionomers, polysiloxane ionomers and their use for the production of cellular polyurethane elastomers

Claim 1

A process for the production of a waterproof, fine-cell polyurethane elastomer having a density of about 300 to 800 kg/m 3 , which comprises reacting (a) an organic polyisocyanate, (b) a polyhydroxyl compound having a molecular weight of 400 to about 8000, (c) water and, optionally, (d) an organic chain extending agent containing at least 2 isocyanate-reactive groups and having a molecular weight of 32 to 399 at an equivalent ratio of isocyanate groups to isocyanate-reactive groups of about 0.90:1 to 1.20:1, wherein a polysiloxane ionomer is added to the water/optional chain extending agent component in an amount of about 0.01 to 5% by weight, based on the reaction mixture as a whole, said polysiloxane ionomer being prepared by a process which comprises forming an NCO-prepolymer by reacting (A) a polysiloxane containing at least two isocyanate-reactive groups corresponding to the formula ##STR5## wherein R may be the same or different and represents a C 1 -C 5 alkyl radical, a C 6 -C 15 aryl radical or a siloxyl radical, n is an integer from 1 to 10, X represents oxygen or NR 1 , R 1 is hydrogen, a C 1 -C 6 alkyl radical or a C 6 -C 15 aryl radical and m is an integer from about 1 to 500, with (B) an organic polyisocyanate, at an equivalent ratio of the reactive XH-groups of the siloxane to isocyanate groups of about 1:1.05 to 1:2, and subsequently reacting the NCO-prepolymer with (C) substantially equivalent quantities of an aqueous solution of a low molecular weight compound containing 1 or 2 NCO-reactive groups and at least one salt group or salt-forming group and converting the salt-forming group, if present, into a salt.