SYNTHESIS AND PROPERTIES OF SULFONATED POLY(ETHER KETONE)S CONTAINING 3,5-DIMETHYL PHTHALAZINONE MOIETIES AS PROTON EXCHANGE MEMBRANE MATERIALS

Sulfonated poly（ether ketone）s containing 3,5-dimethyl phthalazinone moieties（SPPEK-DMs）with different degrees of sulfonation（DS）were synthesized via direct polycondensation from 4-（3,5-dimethyl-4-hydroxyphenyl）-2,3- phthalazinone,4,4’-difluorobenzophenone and 3,3’-disulfonate-4,4’-difluorobenzophenone.The chemical structure of SPPEK-DMs was characterized by FTIR and;H-NMR.Thermal stability of SPPEK-DMs was characterized by the thermogravimetric analysis.The membranes prepared from SPPEK-DMs exhibited ion exchange capacities（IEC）ranging from 0.93 mmol·g;to 1.86 mmol·g;.Water uptake,swelling,oxidative stability and methanol permeability of SPPEKDMs membranes were investigated.SPPEK-DMs membranes exhibited high oxidative stability.The methanol permeability values of SPPEK-DMs membranes were in the ranee 5.15×10;-6.61×10;cm s,which was much lower than those of Nafionl 17.The proton conductivity of SPPEK-DM40 membranes was 1.1×10;Scm;at 70℃.