Organosilicone polymers in polyurethane foams for carpet backing

A process for providing a backing on a carpeting material which comprises

• I. applying a curable froth which is substantially structurally stable, but workable at ambient temperatures, to the back of a carpeting material, said froth comprising
• a. an organic polyisocyanate;
• b. an active hydrogen compound reactive with said polyisocyanate to form a polyurethane;
• c. a high molecular weight linear siloxane-polyoxyalkylene block copolymer selected from the class consisting of
• i. Hydrolyzable (AB).sub.n block copolymers having the average formula
• [(R.sub.2 SiO).sub.x (C.sub.n H.sub.2n O).sub.y ].sub.d
• wherein R represents a monovalent hydrocarbon radical free from aliphatic unsaturation;
• n is an integer of 2 to 4 inclusive;
• x is an integer of at least 7;
• y is an integer of at least 4;
• d is an integer of at least 4;
• the average molecular weight of each siloxane block ranges from about 500 to about 10,000;
• the average molecular weight of each polyoxyalkylene block ranges from about 300 to about 10,000;
• the siloxane blocks constitute from about 20 to about 50 weight percent of the copolymer;
• the polyoxyalkylene blocks constitute about 80 to about 50 weight percent of the copolymer;
• and the block copolymer has an average molecular weight of at least about 65,000;
• and
• ii. Non-hydrolyzable (AB).sub.n block copolymers having the average formula
• (--Y(R.sub.2 SiO).sub.a R.sub.2 SiYO][C.sub.n H.sub.2n O).sub.y --.sub.d
• wherein R, n, y and d are the same as defined above;
• wherein a is an integer of at least 6;
• wherein y represents a divalent organic group attached to the adjacent silicon atom by a carbon to silicon bond and to the polyoxyalkylene block by an oxygen atom;
• wherein the average molecular weight of each siloxane block ranges from about 500 to about 10,000;
• wherein the average molecular weight of each polyoxyalkylene block ranges from about 300 to about 10,000;
• wherein the siloxane blocks constitute about 20 to about 50 weight percent of the copolymer;
• wherein the polyoxyalkylene blocks constitute about 80 to about 50 weight percent of the copolymer;
• and wherein the block copolymer has an average molecular weight of at least about 30,000;
• and
• d. an inert normally gaseous gas substantially uniformly dispersed throughout said froth;
• Ii. shaping said froth into a desired shape;
• and
• Iii. maintaining the resultant shaped froth at a temperature sufficient to cure it and set its shape so as to form a cured polyurethane foam backing on said carpeting material.