To test the success of the end-functionalization experiment and the reactivity of the functional chain ends, we reacted poly-Nb films terminated with styrene and 4-vinylpyridine with methyl iodide under reflux in nitromethane, conditions which have been used to quaternize pyridyl nitrogen groups in other reports. Inert styrene-terminated polymer should not change under these conditions, but the pyridine end group of should become positively charged, resulting in a dramatic change in surface energy. After functionalization, the styrene-terminated film (a) displayed no change in contact angle. However, the pyridinefunctionalized brush (b) displayed a considerable increase in hydrophilicity, with its water contact angle changing from 62 • to 20 • . (Figure )