Spatial and Temporal Control of Chemical Structure for Biofouling Resistant, High Fouling Release Surfaces

摘要

This program seeks to understand the spatial and temporal chemistry required for new antifouling/fouling release polymer coatings from chemically patterned surfaces with different time responses to their environment. Our work focuses on preparing and testing new polymers with amphiphilic structures. Here we summarize several novel amphiphilic polymers prepared in the past year as well as a novel polymer brush system which allows us to produce chemically patterned surfaces for biofouling assays. This new brush patterning system will allow us to test the effect of chemical pattern length scales on the settlement of marine organisms. Those polymers have been synthesized and fully characterized. Glass slides or silicon wafers are coated with polymers through optimized multilayer processes established in our labs and then the surface properties are analyzed. Surface analytical methods include imaging X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS), atomic force microscopy (AFM) and neutron reflection (NR) as well as water and/or bubble contact angle studies. Such measurements provide essential feedback to allow us to discern the connections between the molecular connectivity and microstructure of our surfaces and their fouling resistance/release. In situ neutron reflectivity measurements have given us new insight into the structural rearrangements of hydrophobic polymer brushes when immersed in water. In addition, studies of those functional polymer coated surfaces with ONR investigators such as M. Callow, D. Wendt and M. Hadfield provided direct evaluation of the antifouling performance of these surfaces. Surfaces coated with our specialized polymers have been evaluated using settlement and release assays involving Navicula and Ulva Lima. Several polymer coatings showed comparable, in some cases better, antifouling and fouling release properties than traditional PDMS-based coatings.