Nitroxide‐mediated radical polymerization of 4‐vinylpyridine and its application on modification of silicon substrate

Abstract

AbstractThe poly(4‐vinylpyridine) with hydroxyl end group and narrow polydispersity was synthesized by polymerization of 4‐vinylpyridine by the use of nitroxide initiator based on 4‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl and azobisisobutyronitrile. The effects of different initiator amounts and reaction time on polymerization rate, molecular weight, and molecular weight distribution of the poly(4‐vinylpyridine) were investigated at bulk polymerization. The experimental results have shown that the polymerization of 4‐vinylpyridine is a controlled living free‐radical polymerization; the molecular weight is proportional to reaction time; and the molecular weight and molecular weight distribution are affected by molar ratios of [4‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl]/[azobisisobutyronitrile]. By varying the ratio of 4‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl to azobisisobutyronitrile, the poly(4‐vinylpyridine) with narrow polydispersity can be obtained. X‐ray photoelectron spectroscopy results show that the synthesized poly(4‐vinylpyridine) can be tethered on the surface of silicon wafer through the reaction between hydroxyl end of poly(4‐vinylpyridine) and native silicon oxide layer on the wafer surface. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2687–2692, 2002