ABSOLUTE RATE CONSTANTS FOR RADICAL-MONOMER REACTIONS - THE NITROXIDE METHOD

Abstract

A method is described for determining the absolute rate constants for the first few propagation steps in radical polymerization. The procedure involves a product analysis of the oligomeric alkoxyamines formed when an initiator is decomposed in monomer containing a very low concentration of a nitroxide radical scavenger. The method is illustrated with analysis of data for methyl acrylate. The rate constants for the first two propagation steps for polymerization of this monomer, kp(1) and kp(2), are at least an order of magnitude greater than kp(average). Values of the absolute rate constants for reactions of phenyl and primary alkyl radicals with methyl acrylate are also estimated. © 1992 Spr..