Poly(quinoxalones): Synthesis and properties

A new monomer synthesis and milder polymerization conditions compatable with α-ketoesters have been developed for the preparation of high molecular weight polyquinoxalones PQOs from bis(α-ketoesters) and bis(o-diamines). More flexible PQO structures could be prepared in N-methylpyrrolidone NMP in the presence of an acid catalyst. Methanesulfonic acid was used when complications occurred in the NMP-based synthesis, and afforded polymers which were fully NMP soluble. The materials displayed excellent dimensional and thermal stability, and as PQO is fully cyclized, curing processes were not required. We feel this combination of properties indicate that certain PQO structures may find useful application in microelectronics fabrication, as well as in other fields demanding new high performance materials.