Kenji Miyatake and Allan S. Hay
Three arylene difluoride monomers containing phosphine oxide (1), phosphinic acid (2), or phosphinate ester (3) groups were prepared and polymerized with bisphenol A to give novel poly-(arylene ether)s (4, 5, and 6). The polymers obtained had moderate molecular weights (ηinh: 0.14–0.30 dL g−1 in N-methylpyrrolidinone) and glass-transition temperatures (Tg: 102–200°C), depending on the phosphine group in the main chain. Using bis(4-fluorophenyl)sulfone as a comonomer improved the polymerization to give copolymers with higher solution viscosities. The stoichiometric investigation revealed that 7 mol % excess of fluoride monomer gave the highest molecular weight copolymer 8 with ηinh of 0.78 dL g−1, which had a Tg of 176 °C, a Td10% of 432 °C, and formed a hard film by casting from solution.