Patent ID: 8604093

Claim:
A method for fabricating a fire-resistant polyurethane foam, comprising premixing a polyisocyanate and a hydroxyl-containing inorganic fire retardant to form a first premixture, wherein the polyisocyanate reacts with the hydroxyl-containing inorganic fire retardant to form a chemical bond; premixing a polyol, a blowing agent, and the hydroxyl-containing inorganic fire retardant to form a second premixture; and mixing the first premixture and the second premixture to proceed with a foaming reaction to obtain a fire-resistant polyurethane foam, wherein the hydroxyl-containing inorganic fire retardant comprises particles sizes of 0.5-5 μm, 5-20 μm, and 20-100 μm in a weight ratio of 1:0.1-2:0.1-2.