L-valine were also examined, but surface grafting was not achieved. The thickness of the chemisorbed film, which ranged up to 800 Å, was measured using ellipsometry, and the conformation of the polymer, which can exist as an R-helix (right-or left-handed), β-sheet (parallel or antiparallel), and/or random coil, was determined by Fourier transform infrared spectroscopy (FTIR). Contact angle measurements were also performed to calculate the dispersive and polar surface energies of the film. The thermal stability of the monomer was important in the formation of the polymer film, and benzyl moieties present in the side chain seemed to provide that stability. The resulting film conformation on the surface corresponded well to that observed in the bulk. A large initial growth rate was observed for R-helical and parallel β-sheet structures, while a relatively slow rate was found for antiparallel β-sheets. The decrease in the rate of the polymerization at longer reaction times may be attributed to the physical blocking or chemical transformation of the amino end groups.

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