Lee, Wonmok Kim, Haekyoung Lee, Hyunjung 2024-01-20T23:02:14Z 2024-01-20T23:02:14Z 2021-09-03 2008-07-15 0376-7388 https://pubs.kist.re.kr/handle/201004/133319 A diblock copolymer ionomer containing a rubbery poly(dimethylsitoxane) block has been developed as a proton exchange membrane for direct methanol fuel cell (DMFC). The partially sulfonated polystyrene-b-poly(dimethylsitoxane) (sPS-b-PDMS) membrane with 38% sulfonation degree exhibited 3 times lower methanol permeability and 2.6 times higher membrane selectivity (proton conductivity/methanol permeability) compared to Nafion (R) 115 at 25 degrees C. Coexistence of microphase domains and ionic clusters was confirmed from the morphological studies by small-angle X-ray scattering and tapping-mode atomic force microscopy. Gas chromatographic analysis revealed that water/methanol selectivity of sPS-b-PDMS was 20 times higher than that of Nafion (R) 115. Such a high water/methanol selectivity can be attributed to the existence of PDMS microdomains minimizing methanol permeation through hydrophilic ion channels. sPS-b-PDMS membranes were fabricated into membrane electrode assembly (MEA), and air-breathing DMFC test for these MEAs showed a better performance compared to the MEA composed of Nafion (R) 115. (C) 2008 Elsevier B.V. All rights reserved. English ELSEVIER BLOCK-COPOLYMERS CONDUCTIVITY MORPHOLOGY SCATTERING CROSSOVER IONOMERS SYSTEMS Proton exchange membrane using partially sulfonated polystyrene-b-poly (dimethylsiloxane) for direct methanol fuel cell Article 10.1016/j.memsci.2008.03.066 1 JOURNAL OF MEMBRANE SCIENCE, v.320, no.1-2, pp.78 - 85 JOURNAL OF MEMBRANE SCIENCE 320 1-2 78 85 scie scopus 000257834700008 2-s2.0-46349109514 Engineering, Chemical Polymer Science Engineering Polymer Science Article BLOCK-COPOLYMERS CONDUCTIVITY MORPHOLOGY SCATTERING CROSSOVER IONOMERS SYSTEMS proton exchange membrane direct methanol fuel cell block copolymer poly(dimethylsiloxane) methanol permeability