Preparation and properties of sulfonated poly (2, 6-dimethyl-1, 4- phenylene oxide) / ionic liquid /phosphoric acid high temperature proton exchange composite membrane

A SPPO/IL composite membrane was obtained by self-assembly using the SPPO with the highest degree of sulfonation and the prepared ionic liquid (1-methyl-3-methylimidazolium). SPPO/IL composite membrane is doped with phosphoric acid to form SPPO/IL/PA composite membrane. The SPPO/IL composite membrane is immersed in PA for 24 h, the ion conductivity reaches 36.1 mS/cm. The mechanical stability (350°C), swelling (area 2.26%, volume 2.58%), and...