| Minimally-adhesive coatings based upon amphiphilic hybrid structures of hyperbranched fluoropolymer (HBFP) and linear poly(ethylene glycol) (PEG) or poly(ethylene oxide) (PEO) were prepared, and their potential applications as efficient non-toxic marine anti-fouling and fouling-release coatings, were investigated. HBFP is a unique class of material that exhibits properties of hyperbranched polymers (low viscosity, high solubility) as well as those of fluoropolymers (low surface energy, low adhesive and cohesive forces), while PEG surfaces are known to be highly resistant to protein adsorption, and bacterial adhesion. The HBFP and PEG, when co-deposited onto a surface, undergo thermodynamically-induced phase segregation due to mutual incompatibility, and upon kinetic-trapping of the phase-separated domains through crosslinking, tunable surface topographies and morphologies accompanied by sufficient variability in surface composition with microscopic and nanoscopic resolutions were achieved. It was hypothesized that a high degree of heterogeneity in the surface composition, wettability and topography is imperative for the coating to be efficient in minimizing settlement as well as facilitating the release of fouling organisms, which adhere to the surfaces via secretion of hydrophobic or hydrophilic protein or glycoprotein adhesive segments. Towards this objective, linear bis(3-aminopropyl) terminated PEG was employed to generate crosslinked amphiphilic networks via nucleophilic substitution of the HBFP end groups by the amine termini of the PEG. The surfaces exhibited unique morphological behavior that is manifested in the thermal and mechanical properties investigated, whereas the relative composition of PEG vs HBFP on the surface was found to exhibit a direct correlation with the bulk composition. The behavior of the crosslinked HBFP-PEG materials towards bio-fouling was investigated by way of protein and glycoprotein adsorption studies using fluorescence microscopy.; In this dissertation, the preparation of HBFP-PEG crosslinked network coatings is discussed along with the characterization and investigation of their potential use as efficient marine anti-fouling, and fouling-resistant surfaces. Synthesis of amphiphilic star polymers with HBFP core and PEO arms, and their characterization in organic as well as aqueous solutions, is also presented. (Abstract shortened by UMI.)... |
