Triblock SEBS/DVB crosslinked and sulfonated membranes: Fuel cell performance and conductivity. Issue 28 (7th March 2021)

• Record Type: Journal Article
• Authors: Teruel‐Juanes, Roberto; del Río, Carmen; Gil‐Castell, Oscar; Primaz, Carmem; Ribes‐Greus, Amparo
• Is Part Of: Journal of applied polymer science. Volume 138:Issue 28(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-03-07
• Subjects: copolymers -- crosslinking -- fuel cells -- membranes -- polyelectrolytes; Polymers -- Periodicals; Polymerization -- Periodicals; 668.9
• DOI: 10.1002/app.50671
• Languages: English
• ISSNs: 0021-8995

Abstract

Abstract: A set of styrene‐ethylene‐butylene‐styrene triblock copolymer (SEBS) membranes with 10 or 25 wt% divinyl‐benzene (DVB) as a crosslinking agent were prepared and validated. Physicochemical characterization revealed suitable hydrolytic and thermal stability of photo‐crosslinked membranes containing 25 wt% DVB and post‐sulfonated. These compositions were evaluated in H2 /O2 single cells, and electrical and proton conductivities were furtherly assessed. The membranes with the milder post‐sulfonation showed greater proton conductivity than those with excessive sulfonation. In terms of electrical conductivity, a universal power law was applied, and the values obtained were low enough for being used as polyelectrolytes. At the analyzed temperatures, the charge transport process follows a long‐range pathway or vehicular model. Finally, fuel cell performance revealed the best behavior for the membrane with 25 wt% DVB, photo‐crosslinked during 30 min and mild sulfonated, with a promising power density of 526 mW·cm −2 . Overall, the results obtained highlight the promising fuel cell performance of these cost‐effective triblock copolymer‐based membranes and indicate that higher sulfonation does not necessarily imply better power density. Abstract : The combination of styrene‐ethylene‐butylene‐styrene triblock copolymer (SEBS) together with a thermally activated crosslinking procedure with divinyl benzene (DVB) and subsequent mild post‐sulfonation allowed for the preparation of promising candidates for being exploited as cost‐effective membranes for proton exchange (H2 /O2 ) fuel cell applications.