FOAM AND PROCESS FOR PRODUCING THE SAME

摘要

A foam which comprises an inorganic filler as the main material and a halogen-free organic substance and which generates no harmful gases in a fire and is excellent in incombustibility, lightweight properties, non-water-absorbing properties, and heat-insulating properties is obtained by the technique in which an isocyanate is contacted with water to cause a reaction and thus generate gas bubbles. The process for producing the foam comprises mixing an isocyanate with an elastomer resin such as a nitrile/butadiene rubber and an inorganic filler such as magnesium hydroxide, aluminum hydroxide, or calcium carbonate to obtain a mixture, kneading it, subsequently pressurizing and heating the mixture to obtain a compound, packing it into a mold having an adequate number of holes, and putting this mold in a water tank, whereby water infiltrates into the compound and the isocyanate contained in the ingredients hence hydrolyzes to generate gas bubbles comprising carbon dioxide and nitrogen and cause a foaming phenomenon and thereby expand the compound. Thus, a closed-cell foam having incombustibility/flame retardancy is molded.