The synthesis of poly(phenylene sulfide sulfone) in ionic liquids at atmospheric pressure

A novel chemical approach to prepare the high performance polymer poly(phenylene sulfide sulfone) under mild conditions was presented based on 4,4-difluorodiphenylsulfone and sodium sulfide (Na2S) in i-pmim PF6 (IL)/MImBS (ZI) at atmospheric pressure and compared with conventional methods. The highest molecular weight (2.5 × 104) and yield (>99%) polymers were synthesized in IL/ZI in the presence of sodium carbonate and sodium hydroxide at 200 °C for 4 h. ZI can significantly improve solubility of the basic inorganic salt Na2S. And using ILs as solvents made removing toluene by purging with nitrogen much easier and the time was shortened significantly from 5–8 min to 1–2 min. In addition, the ILs can be recycled easily and still possess excellent performance.