Pulsed initiation polymerization as a means of obtaining propagation rate coefficients in free-radical polymerizations. II Review up to 2000

The application of the pulsed initiation polymerization technique (PIP) to determine propagation rate coefficients has evolved into a valuable tool. The number of monomers studied has rapidly increased since 1987. Besides homopropagation rate coefficients also copolymerizations are studied extensively. The calibration of the size exclusion chromatography is still a limiting factor in studying delicate differences in reactivities, for example in families of monomers like that of the methacrylates. In studying solvent effects in propagation, PIP is capable of disclosing even small solvent effects, typically in the order of magnitude of plus or minus 20%. For some families of monomers PIP does not result in reliable parameters. The reasons for the breakdown of the PIP technique with the acrylates are discussed.