Synthesis of hydrophilic ion-exchange fluoropolymers containing sulpho- and both sulpho- and carboxyl groups

Abstract

Copolymers of tetrafluoroethylene (TFE) with ethylene having non-alternating structures and high contents of TFE or ethylene blocks were synthesized. Some of the physical properties of the copolymers were examined. The polymers with high ethylene contents as well as TFE, hexafluoropropene and acrylic acid polymers were sulphonated; hydrophilic products with ion-exchange capacities of 0.70 and 1.75 meq/g were obtained. Their temperature and phase characteristics were determined. The resulting sulpho- and both sulpho- and carboxyl-containing copolymers have good thermal and ion-exchange characteristics and can be used for the preparation of cation-exchange membranes.