Thermally Cross-Linked Anion Exchange Membranes from Solvent Processable Isoprene Containing Ionomers
Abstract
Random copolymers of isoprene and 4-vinyl- benzyl chloride (VBCl) with varying compositions were synthesized via nitroxide-mediated polymerization. Subsequent quaternization afforded solvent processable and cross-linkable ionomers with a wide range of ion exchange capacities (IECs). Solution cast membranes were thermally cross-linked to form anion exchange membranes. Cross-linking was achieved by taking advantage of the unsaturations on the polyisoprene backbone, without added cross-linkers. A strong correlation was found between water uptake and ion conductivity of the membranes: conductivities of the membranes with IECs beyond a critical value were found to be constant related to their high water absorption. Environmentally controlled small-angle X-ray scattering experiments revealed a correlation between the average distance between ionic clusters and the ion conductivity, indicating that a well-connected network of ion clusters is necessary for efficient ion conduction and high ion conductivity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 2015
- Accession Number
- ADA623344
Entities
People
- Andrew M Herring
- Ashley M. Maes
- E. Bryan Coughlin
- S. P. Ertem
- Soenke Seifert
- Tsung-han Tsai
Organizations
- Colorado School of Mines