Surfaces of novel block copolymers with amphiphilic side chains were studied for their ability to influence the adhesion of marine organisms. The surface-active polymer, obtained by grafting fluorinated molecules with hydrophobic and hydrophilic blocks to a block copolymer precursor, showed interesting bioadhesion properties. Two different algal species, one of which adhered strongly to hydrophobic surfaces, and the other, to hydrophilic surfaces, showed notably weak adhesion to the amphiphilic surfaces. Both organisms are known to secrete adhesive macromolecules, with apparently different wetting characteristics, to attach to underwater surfaces. The ability of the amphiphilic surface to undergo an environment-dependent transformation in surface chemistry when in contact with the extracellular polymeric substances is a possible reason for its antifouling nature. Near-edge X-ray absorption fine structure spectroscopy (NEXAFS) was used, in a new approach based on angle-resolved X-ray photoelectron spectroscopy (XPS), to determine the variation in chemical composition within the top few nanometers of the surface and also to study the surface segregation of the amphiphilic block. A mathematical model to extract depth-profile information from the normalized NEXAFS partial electron yield is developed.

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A detailed investigation of the atom transfer radical polymerization of methyl methacrylate (MMA) with the ethyl 2-bromoisobutyrate (2-EiBBr)/CuBr/N,N,N‘,N‘,N‘ ‘-pentamethyldiethylenetriamine (PMDETA) catalyst system in anisole was performed at 30 °C. The number-average molecular weight of the PMMA was observed to increase gradually and linearly while the polydispersity index (PDI) remained narrow throughout the reaction time. The summary of these studies showed that PMMA with molecular weight up to 105 g/mol could be synthesized in a controlled fashion at room temperature. The new route developed was utilized to demonstrate the facile synthesis of ABC and CBABC multiblock copolymers of styrene, tert-butyl acrylate (tBA), and MMA. For this, the starting blocks of AB and BAB were synthesized by coupling different ATRP methods reported. The end-block consisting of PMMA was synthesized by the ATRP of MMA using the CuCl/PMDETA catalyst system (halogen exchange) with anisole as the solvent at room temperature. Gel permeation chromatography (GPC) was used to determine the M n, M w, and PDI of the polymers synthesized. The PDI of all the block copolymers is found to be low (1.1−1.4). 1H NMR spectroscopy was used to determine the chemical composition of the block copolymers. Additional evidence for the blocky nature was also gained from FT-IR and thermal analysis.