In a similar experiment, (not shown) a poly-Nb film quenched with tert-butyl acrylate displayed a 30 • contact angle change after 1 hour heating at 150 • C. Tert-butyl esters hydrolyze in moist air above 100 • C to give polar carboxylic acid groups. A poly-Nb film quenched with vinylferrocene displayed the characteristic reversible redox couple of surface-bound ferrocene near 0.5V vs. Ag/Ag + . (Figure )