Synthesis and Characterization of Polyetherquinoline and Polyetherquinoxaline

The synthesis and characterization of new sulfonated polyetherquinolines and polyetherquinoxalines are described. Two-step polymerization method is used to prepare the sulfonated polyetherquinoline copolymers from 2,4 quinolinediol, 4,7-dichloroquinoline and bisphenol A, bis (4-fluorophenyl) sulfone and difluorobenzophenone. Flexible, transparent, and mechanically strong membranes are successfully obtained from polyetherquinolines blended with sulfonated polyetheretherketone. The membranes were characterized with differential scanning calorimetry (DSC), ion-exchange capacity, and proton conductivity measurements and FTIR. These results showed that the membranes had good thermal stability and high conductivity (3.6 x 10^-2 S/cm) was achieved from blended polyetherquinoline (43% wt.) and sulfonated polyetheretherketone (57 % wt.). The DSC results indicated that the glass transition temperature (Tg) was 225ºC.