Fire-retardant anhydride copolymers

摘要

Copolymers of monovinyl aromatic monomers and the anhydrides of ethylenically unsaturated dicarboxylic acid monomers are blended with water as a blowing agent, bromodiphenylethers as fire retardants, and metal oxides as synergist for the ethers to form a composition which can be foamed to densities of between 1 and 10 pounds per cubic foot, said composition having fire retardant properties.