Rigid polyurethane foam containing polyester residue digestion product

Abstract From the Canadian patent

Rigid polyurethane foam is produced from polyisocyanate and polyol wherein 5-30% by weight of the polyol ingredient is a digestion product of polyalkylene terephthalate residues or scraps digested with organic polyols. The resulting rigid polyurethane foam exhibits uniform density and when, compared with a corresponding polyurethane foam which does not include the said digestion products exhibits equivalent, or superior physical strength properties. With fire retardant rigid polyurethane foams wherein the organic polyol ingredient includes halogenated organic polyols use of 5-, 30% by weight of the said digestion product in the organic polyol ingredient achieves a rigid fire retardant …