1,3-Isobenzofurandione, 5,5'-carbonylbis-, polymer with 2,4-diisocyanato-1-methylbenzene and 1,1'-methylenebis(4-isocyanatobenzene) 119912-01-5 58698-66-1 Benzophenonetetracarboxylic dianhydride, 2,4-toluenediisocyanate, 4,4'-methylenediphenyldiisocyanate polyimide