​ ​Seminar on Multi-Functional Superhydrophobic Polymer Surfaces

Low surface energy polymers are especially well-suited to form superhydrophobic surfaces because they can be easily processed into a wide range of useful forms using techniques ranging from lamination to 3D printing.  Additional functionality can be achieved by further modifying the surface structure and/or incorporating catalytically active particles.  In this presentation, I will discuss different approaches to increasing the functionality of superhydrophobic surfaces for specific applications.  In one approach, nanoscale topography is formed in the surface of a fluoropolymer using a novel lamination-peeling mechanism.  The nanoscale roughness, low refractive index, and hierarchical topography combine to impart anti-reflective properties, reducing reflections by more than 75%.  These superhydrophobic surfaces exhibit anti-soiling behavior in the presence of condensed water owing to the high mobility of the solid-liquid-vapor triple contact line.  Coalescence-induced jumping condensation is stable on these surfaces to large values of sub-cooling (ΔT > 70 K).  In a second approach photo-catalytic sensitizer particles are partially embedded into a surface created by 3D printing a polydimethylsiloxane, thereby enabling the generation of reactive singlet oxygen that can diffuse across the plastron and efficiently kill microbes while preventing direct contact of the catalyst with biofluids.  Complete biofilm inactivation (>5 log killing) of Porphyromonas gingivalis, a bacterium implicated in periodontal disease, is achieved using a superhydrophobic singlet oxygen delivery device.

Alan Lyons received a B.Sc. in chemistry from Brown University and Ph.D. in polymer chemistry from Polytechnic University (now NYU-Tandon).  He was a Distinguished Member of Technical Staff with the research division of Bell Laboratories prior to joining the City University of New York, as a Professor in the Department of Chemistry in 2008.  He has authored over 45 publications as well as 38 issued patents.  Based on this work, he has co-founded two companies: ARL Designs LLC, which develops advanced coatings for glass and metal; and SingletO2 Therapeutics LLC, which develops device for oral healthcare.