Rate coefficients of free-radical polymerization deduced from pulsed laser experiments

Pulsed laser techniques have enormously improved the quality by which rate coefficients of individual steps in free-radical polymerization may be measured. Pulsed laser initiated polymerization (PLP) in conjunction with size-exclusion chromatography (SEC) yields the propagation rate coefficient, k(p). The PLP-SEC-technique has been applied to a wide variety of homopolymerizations and copolymerizations, either in bulk or in solution. In addition to reporting kinetic data, experimental details of PLP, of SEC, and of the limitations associated with the accurate determination of the MWD are discussed. The single pulse (SP)-PLP method, which combines PLP with time-resolved NLR spectroscopy, allows for a very detailed insight into the termination rate coefficient, k(t), for homo- and copolymerizations. k(t), data are reported as a function of temperature, pressure, monomer conversion, solvent concentration, and partly also of chain length. This review considers literature up to December 2000. (C) 2002 Elsevier Science Ltd. All rights reserved.