Proton-controlled nitroxide mediated radical polymerization of styrene

作者：Le Du Yann; Binet Laurent; Hemery Patrick; Marx Lucien^*

来源：Journal of Polymer Science Part A: Polymer Chemistry , 2012, 50(14): 2871-2877.

DOI：10.1002/pola.26064

• EPR
• kinetics
• nitroxide-mediated radical polymerization
• pyridyl nitroxide
• stimuli-responsive alkoxyamines
• polystyrene

The pyridyl alkoxyamine, which is composed of the 1-phenylethyl radical and a pyridyl nitroxide fragments, displays protonation-controlled C?ON bond homolysis. Its dissociation rate constant kd value is approximately halved at 100 degrees C in tert-butyl benzene when it is protonated by one equivalent of trifluoroacetic acid. Moreover, the bulk polymerization of styrene at 125 degrees C is performed with a good control over the molecular weight and the dispersity when initiated with this alkoxyamine under its basic and acidic forms but the protonation has induced a strong decreased polymerization rate. In contrast, in the case of n-butyl acrylate, the control over the polymerization is lost for the protonated pyridyl alkoxyamine because the pyridyl nitroxide is less thermally stable under its acidic form.

• 出版日期2012-7-15