US 7,456,229 B2
Process for the production of rigid and semi-rigid foams with low amounts of diisocyanate using polymer polyols characterized by high solids and a high hydroxyl number and the resultant foams
Stanley L. Hager, Cross Lanes, W. Va. (US); Rick L. Adkins, Hurricane, W. Va. (US); and Shriniwas S. Chauk, Sewickley, Pa. (US)
Assigned to Bayer MaterialScience LLC, Pittsburgh, Pa. (US)
Filed on May 31, 2006, as Appl. No. 11/443,811.
Prior Publication US 2007/0282029 A1, Dec. 06, 2007
Int. Cl. C08G 18/00 (2006.01)
U.S. Cl. 521—170  [521/155] 33 Claims
 
1. A rigid or semi-rigid polyurethane foam comprising the reaction product of:
(A) less than 75 pbw, based on 100 pbw of component (B), of at least one polyisocyanate; with
(B) an isocyanate-reactive component having a solids content of at least 40% by weight, an overall hydroxyl number of the liquid, non-solids portion of at least 160, and comprising:
(1) at least 50% by weight of a polymer polyol having a solids content of at least 30% by weight, in which the base polyol of the polymer polyol has a hydroxyl number of at least 70 and a functionality of 2 to 8, and
(2) no more than 50% by weight of one or more second polyols, said second polyol being different than the polymer polyol (1),
with the sum of the %'s by weight of polyols (1) and (2) totaling 100% by weight of (B);
in the presence of
(C) at least one blowing agent;
(D) at least one surfactant; and
(E) at least one catalyst.