Ultrathin film characterization: photoreactive polyacrylamide

The structure and properties of photoreactive polyacrylamide thin films suitable for medical devices are presented. Using a solution deposition process, we report on the influences of polymer concentration, substrate residence time in solution and UV illumination upon the film structure, wettability and frictional properties. Ellipsometry, atomic force microscopy and lateral force microscopy show that increasing polymer concentration and illumination increased the film thickness and uniformity. Dynamic contact angles and frictional coefficients of the modified surfaces depend upon the film structure and thickness for films less than 40Å thick. We also demonstrate the potential of lateral force microscopy for investigating tribology at the nanoscale level.