(225b) Customizing Polyamide Membranes for Liquid, Ion, and Gas Separations Using Electrospray Additive Manufacturing

Polyamide is a versatile material that has had enormous impact on membrane technology. While nylon-based membranes exist in a number of applications, its most noteworthy contribution has been in revolutionizing the field of reverse osmosis. In-situ formation of polyamide membranes through the interfacial polymerization process launched the new TFC membrane platform. These membranes performed extremely well in desalination applications and their formation was scalable, enabling their dominance as the most used membrane for desalination over the past four decades. In that time, we have ignored some interesting opportunities to use polyamide membranes for other applications. As an ion containing polymer, polyamide offers cation exchange potential and we have explored the use of sulfonated versions of aromatic polyamide for ion exchange. In another application inspired by our honoree Prof. Ingo Pinnau, we have considered this highly crosslinked and glassy polymer as a gas separation membrane. Using polyamide for these applications is reliant on our new additive manufacturing technique that builds these membranes in a layer-by-layer approach which allows for customization of polyamide chemistry in a way that is impossible with conventional interfacial polymerization. We believe this technique may unlock even more use cases for polyamide TFC membranes.