PBI PPy x coPSF Blends

In recent years a series of polysulfone copolymers bearing pyridine units in the main chain have been prepared and studied. These copolymers will be described in the following section and thier chemical structure can be seen in Fig. 10. Blends of the copolymer I50 (Fig. 10), which hereafter will be called PPy(50)coPSF (bearing 50% pyridine), with mPBI have been prepared and studied thoroughly with respect to their miscibihty behavior, mechanical properties, their doping ability with phosphoric acid and conductivity values, as well as their thennal and oxidative stability 69,70,71 

The interesting feature of this new polymer blend is that, in contrast to pure FBI and PBI/SPSF, the miscible PBI/PPy(50) coPSF polymer blends are chemically stable under the highly oxidative Fenton test conditions. In this respect it can be considered as chemically stable under the aggressive oxidative conditions (peroxide species formation at the cathode) under fuel cell operation. 

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