Polymers with Very Low Polydispersities from Atom Transfer Radical Polymerization

Science  10 May 1996:
Vol. 272, Issue 5263, pp. 866-868
DOI: 10.1126/science.272.5263.866


A radical polymerization process that yields well-defined polymers normally obtained only through anionic polymerizations is reported. Atom transfer radical polymerizations of styrene were conducted with several solubilizing ligands for the copper(I) halides: 4,4′-di-tert-butyl, 4,4′-di-n-heptyl, and 4,4′-di-(5-nonyl)-2,2′-dipyridyl. The resulting polymerizations have all of the characteristics of a living polymerization and displayed linear semilogarithmic kinetic plots, a linear correlation between the number-average molecular weight and the monomer conversion, and low polydispersities (ratio of the weight-average to number-average molecular weights of 1.04 to 1.05). Similar results were obtained for the polymerization of acrylates.