Ambiguous Polymeric Surfaces For Marine Anti-Fouling Applications
Marine biofouling is defined as the undesirable accumulation of biomacromolecules, microbial slimes, plants, and animals on a surface immersed in seawater. Due to the extra surface area and roughness generated by biofouling, vessels moving through the ocean require more energy to overcome frictional forces. Consequently, significant savings in both fuel consumption and emissions can be realized by combating biofouling. While traditional methods of biofouling control have generally incorporated ablative metallic biocide containing materials, these coatings are now being phased out due to their inherent risk to the environment. This has opened the door for the development of novel polymeric materials, dependant on a combination of surface chemistry and bulk modulus, as a means of marine fouling control. This dissertation will explore the development, characterization and assay of several different multilayer polymeric coatings consisting of a relatively thick low modulus poly(styrene)-block-poly(ethylene-ran-butylene)-block-poly(styrene) (SEBS) thermoplastic elastomer base layer and a relatively thin surface active block copolymer (SABC) consisting of poly(styrene) and a functional block derived from either poly(acrylic acid) or poly(isoprene). Additionally, a fundamental study comparing the performance of surfaces functionalized with polymer brushes to surfaces functionalized with self-assembled monolayers will be presented. Bulk chemical characterization of the materials produced will be related using methods including 1H NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, elemental analysis, and gel permeation chromatography. Surface characterization of the materials produced meanwhile will be presented using X-ray photoelectron spectroscopy (XPS), dynamic water contact angle analysis, and nearedge X-ray adsorption fine structure (NEXAFS) measurements. Biofouling performance meanwhile will be evaluated using a combination of biofouling assays including settlement and release of the green alga Ulva and the diatom Navicula and tests of the adhesion characteristics of the protein bovine serum albumin (BSA). Correlations between surface chemistry, coating modulus, and fouling settlement and release behavior will be identified and specific conclusions on the fouling performance of these various coating formulations will be reported on.
Marine Anti-Fouling Applications
dissertation or thesis