Designing a New Ionomer from Scratch - Pushing Polypoms to the Limit

• Main Authors: Horan, James L., Kuo, Mei-Chen, Sachdeva, Sonny, Ren, Hui, Perdue, Andrew S., Dec, Steven F., Yandrasits, Michael A., Hamrock, Steven J., Frey, Matthew H., Herring, Andrew M.
• Format: Conference Proceeding
• Language: English
• ISSN: 1938-5862; 1938-6737
• DOI: 10.1149/1.3210663

We have fabricated proton conducting films using monomers based on vinyl substituted silicotungstic acid heteropoly acids (HPAs) and acrylate co-monomers. In this work we probe the limits of this system based on increasing the weight loading of the HPA to 85 wt%. Although impressive proton conductivities can be achieved with these films under hotter and drier operating conditions than in conventional proton exchange membranes, the materials have mechanical limitations. We show that very different film morphologies can be prepared based on whether or not the film is polymerized thermally or by UV light. In general the UV cured films have superior proton conductivity, but have a linear morphology resulting in a brittle film. The thermally cured films have a clustered morphology with good mechanical attributes but have poor proton conductivity.