Polyalkylated aromatic monomers and polymers. Part 3. —Some cross-linkable polyimides derived from bis(aminobenzoyl)durenes

Abstract

Bis(m- and bis(p-aminobenzoyl)durene have been prepared from the corresponding vitro compounds by catalytic transfer hydrogenation. The anomalous ¹H and ¹³C NMR spectra of the latter are possibly attributable to restricted rotation about the durene–CO bond combined with mesomeric interaction of the amino and carbonyl groups. Polyimides obtained from these two diamines by reaction with bisanhydrides, and end-capped with norbornene units, have been cured thermally like PMR-15 resins, but the cured resins are less stable in air at high temperatures than the commercial thermosets. This inferior thermal stability may be the result of aerial oxidation of the methyl groups.