COMPOSITION FOR PREPARING POLYIMIDE FOAM MATERIALS Russian patent published in 1997 - IPC

FIELD: chemistry of high-molecular weight compounds, in particular, aviation, automobile manufacture and shipbuilding, constructions which require light and strong noncombustible materials. SUBSTANCE: invention provides composite polyimide foam materials based on elastic foams. Composition comprises prepolymer binder and filler. Heat treatment of binder produces elastic polyimide foam. Composition comprises prepolymer binder based or mixture of two aromatic diamines consisting of 4,4'-diaminodiphenyl methane, m- and p-phenylene diamines, 4,4'-diaminodiphenyl ester, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl, 4,4'- -diaminodiphenylsulfone at ratios of 0.2-0.8: 0.8-0.2 and 3,4',4,4'-benzophenontetracarboxylic acid diester and lower aliphatic alcohol. Filler in composition is thermally-resist arimide, aramide and carbon fiber. Ratio of components is as follows, wt.-%: binder, 30-70; filler, 30-70. Composite polyimide material is prepared in two stages. In the first stage, composition is prepared by mixing components or prepregs are prepared by impregnating fiber with binder solution or malt. In the second stage, composition is hardened at 250 C. Density of resulting materials is 0.2-0.5 g/sq.cm. EFFECT: improved properties of the composition. 3 cl, 2 tbl