The connection between microstructure and kinetics in the case of irreversible growth of long (pseudo)copolymers has been discussed, extended and established. The theoretical results have been cast in simple matrix equations which enable one to compute the probability to find any given sequence in terms of ratios of kinetic constants, rather than in terms of stochastic parameters. As an application, the case of regioregular polymerization of vinyl monomers by C1-symmetric coordination catalysts has been considered. In addition to propagation, first order in monomer concentration, chain and site epimerization, both zeroth-order in monomer concentration, have been taken into account. The resulting equations have been tested against a set of literature data obtained by five different catalysts, each operated at five different concentrations, resulting in the evaluation of ratios of kinetic constants. For all catalysts the quantitative analysis of the kinetics confirms that the contribution of chain epimerization is small or negligible in the concentration range examined.
On the Connection between Microstructure and Kinetics of (Pseudo)copolymerization
MONACO, Guglielmo
2001-01-01
Abstract
The connection between microstructure and kinetics in the case of irreversible growth of long (pseudo)copolymers has been discussed, extended and established. The theoretical results have been cast in simple matrix equations which enable one to compute the probability to find any given sequence in terms of ratios of kinetic constants, rather than in terms of stochastic parameters. As an application, the case of regioregular polymerization of vinyl monomers by C1-symmetric coordination catalysts has been considered. In addition to propagation, first order in monomer concentration, chain and site epimerization, both zeroth-order in monomer concentration, have been taken into account. The resulting equations have been tested against a set of literature data obtained by five different catalysts, each operated at five different concentrations, resulting in the evaluation of ratios of kinetic constants. For all catalysts the quantitative analysis of the kinetics confirms that the contribution of chain epimerization is small or negligible in the concentration range examined.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
