A novel polycyclic dihydroxy diimide monomer was synthesized through the photocycloaddition of N-methylolmaleimide to benzene and the reaction of maleimide-benzene photoadduct with formaldehyde. The monomer, which evolved formaldehyde at about 165 degrees C, was subsequently used to prepare low molecular weight polyamineimides and polyurethaneimides. Soluble polyamineimides, prepared with three different aromatic diamine monomers, exhibited initial decomposition temperatures between 277 and 329 degrees C and glass-transition temperatures between 180 and 219 degrees C. An aliphatic polyamineimide prepared from 1,6-hexanediamine was insoluble and had glass-transition and initial decomposition temperatures of 225 degrees C and 294 degrees C, respectively, with prior loss of formaldehyde from end groups. Polyurethaneimides prepared with two aromatic diisocyanates showed loss of formaldehyde in the approximate range of 160-169 degrees C followed by loss of CO2 and glass-transition temperatures of 219 and 233 degrees C. Attempts to prepare polyamideimides resulted in oligomers with a low nitrogen content. Attempts to prepare polyesterimides were unsuccessful.