Biphenylene end-capped polyquinoline pre-polymers (DP = 3,11 and 22) were melt processed in the presence of a nickel catalyst at 325–340°C under 500 psi to give high quality transparent films. Very short cure times (∼ 5 min) were realized, and the resulting films were insoluble, had increased Tg's, and showed improved mechanical properties both above and below the Tg as compared with the uncured resins. The main curing reaction is a chain extension by the conversion of the biphenylene ends to tetrabenzocyclooctatetraene, while a smaller amount of crosslinking takes place. Biphenylene end-capped polyimide, poly(keto-ether-sulfone) and polyphenylquinoxaline pre-polymers also were synthesized. The polyimide pre-polymer (DP=3) was melt processed at 325°C and 500 psi (Ni catalyst) for 15 min to give films that showed good mechanical properties. Friedel Crafts polymerization to yield the biphenylene end-capped poly(keto-ether-sulfone) could not be adequately controlled to give reproducible oligomers. Polyphenylquinoxaline pre-polymers were similarly melt processed to give insoluble films with good mechanical properties. Graphite reinforced composites were prepared from biphenylene end-capped polyquinoline and polyimide pre-polymers. The composites showed excellent initial properties and low weight loss after oxidative aging at 316°C. However, the mechanical properties were severely diminished after aging for 50–100 h at 316°C in air.