Synthesis of Poly(ether ether ketone)s with High Content of Sodium Sulfonate Groups as Gas Dehumidification Membrane Materials

Sodium sulfonate‐functionalized poly‐(ether ether ketone)s derived from Bisphenol A with a degree of sulfonation up to 2.0 were synthesized by aromatic nucleophilic polycondensation of various amounts of 5,5′‐carbonylbis(2‐fluorobenzenesulfonate) ( 1 ), 4,4′‐difluorobenzophenone ( 2 ) and Bisphenol A ( 3 ). Copolymers showed excellent thermal stability and good mechanical properties. The selectivity of water vapor over nitrogen of membranes prepared from copolymers 3a and 3b was determined to be 3.43×10⁶ and 1.05×10⁷, respectively.