Improved Mechanical Compliance in Bicontinuous Cubic Lyotropic Membranes Based on a Cross-Linking Gemini Monomer via Copolymerization with a Non-Cross-Linkable Analog

Membrane materials for use in chemical protective garments for the U.S. military should have >20% reversible stretch without breaking. Copolymerization of a cross-linking gemini lyotropic liquid crystal (LLC) monomer with controlled amounts of a non-cross-linkable analog allows formation of nanoporous, bicontinuous cubic polymer membranes with higher % strain-at-failure values of >20% and lower Young's modulus values while retaining high water vapor transport. Although chemical warfare agent (CWA) simulant vapor rejection decreases with the reduced cross-link density, increased mechanical pliability was achieved, demonstrating that the mechanical properties of these LLC-based, breathable CWA-barrier materials can be modified in this fashion.