Synthesis and properties of sulfonated poly(ether ketone)s containing 3,5-dimethyl phthalazinone moieties as proton exchange membrane materials

• Published in: Chinese journal of polymer science 2012, Vol.30 (4), p.511-519
• Main Authors: Zhang, Shou-hai, Zhou, Juan, Jian, Xi-gao
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Industrial Chemistry/Chemical Engineering; Polymer Sciences
• ISSN: 0256-7679; 1439-6203
• DOI: 10.1007/s10118-012-1129-z

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 1H-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 −1 to 1.86 mmol·g −1 . 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 range 5.15 × 10 −8 –6.61 × 10 −7 cm 2 ·s −1 , which was much lower than those of Nafion117. The proton conductivity of SPPEK-DM40 membranes was 1.1 × 10 −2 S·cm −1 at 70°C.