STUDIES ON A SERIES OF BISARYLIMIDES CONTAINING 4 PHENYLENE RINGS AND THEIR POLYMERS .1. SYNTHESIS AND CHARACTERIZATION OF THE MONOMERS

Two aryl bismaleimides and the corresponding biscitracomides, in which the imide groups were attached to the ends of aromatic residues containing four phenylene rings, were prepared and then purified by preparative high-performance liquid chromatography. Rigorous purification in this way was found to have marked effects on the thermal polymerization characteristics of these compounds as determined by the differential scanning calorimetry technique. The polymerization of bis-4-maleimidophenylmethane and of bis-4-maleimidophenyl ether was also affected by rigorous purification. Samples of the corresponding two bisnadimides containing four phenylene rings were also prepared.