摘要 |
A method of preparing a flame-retardant benzylic-ether phenolic modified foam product and the resulting foam product produced thereby, which method comprises reacting and mixing benzylic-ether phenol-formaldehyde resin, having a hydroxyl number of from about 400 to 600, with from about 50 to 150 parts by weight of a boric-acid catalyst to each 100 parts of the resin, optionally in the presence of melamine, to form a resin prepolymer, and, thereafter, reacting the prepolymer so formed, in the presence of a blowing agent and an organometal catalyst, with a methylene diisocyanate in an exothermic reaction, to provide a nonfriable, substantially closed-cell, flame-retardant benzylic-ether phenolic modified foam product characterized by substantially acid methylene linkages in the resulting thermosetting foam product.
|