Synthesis and Characterization of Poly(ether ketone) Containing Side Sulfonic Acid Group for Proton Exchange Membrane Fuel Cell
Poly(ether ketone)s (PEK) containing 25-75 mol % valeric acid were prepared with bisphenol A, 4,4-dichlorobenzophenone and 4,4-Bis(4-hydroxylphenyl)valeric acid using potassium carbonate in DMAc (dimethyl acetami de) at 165 °C. Copolymers containing carboxylacid group were reduced to hydroxy group by BH3 solution 1M in THF and NaBH4 co-catalyst. Sulfonated poly(ether ketone)s (S-PEK) were obtained by reaction of 1,3-propanesultone and the reduced copolymer (PEK-OH) with sodium methoxide. A series of copolymers were studied by 1H-NMR spectroscopy, differential scanning calorimeter (DSC), and thermo gravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of sulfonated polymers with water and methanol. The S-PEK membranes exhibited proton conductivities from 1.31 10-3 to 3.52 10-3 S/cm, water swell from 12.70 to 35.50 %, IEC from 0.45 to 0.75 meq/g and methanol diffusion coefficients from 3.65 10-7 to 5.10 10-7 cm2/S at 25 °C.
Hyungsun Kim, JianFeng Yang, Tohru Sekino, Masakazu Anpo and Soo Wohn Lee
D. W. Seo et al., "Synthesis and Characterization of Poly(ether ketone) Containing Side Sulfonic Acid Group for Proton Exchange Membrane Fuel Cell ", Materials Science Forum, Vol. 658, pp. 41-44, 2010