Patent ID: 11905707

Abstract:
Foam wall structures and methods for making them are described. The wall structures include a frame, a foam panel overlying a front surface of the frame, and a polyurethane foam layer disposed in a cavity of the wall structure. The polyurethane foam layer has a density, as determined by ASTM D1622-14, of at least 44 kg/m3(2.75 lb/ft3) and exhibits ASTM E84-16 Class A flame spread and smoke development characteristics. The polyurethane foam layer is the cured reaction product of a polyurethane foam-forming composition that includes a polyisocyanate, an aromatic polyester polyol having a functionality of greater than 2.5 and an OH number of at least 300 mg KOH/g, which is present in an amount of at least 50% by weight, based on the total weight of the polyurethane foam-forming composition less the weight of the polyisocyanate, a catalyst, and a blowing agent composition. The blowing agent composition includes water and a hydrofluoroolefin.