Critical evaluation of rate parameters for chain-length-dependent termination of styrene and n-alkyl methacrylates, leading to the provision of benchmark data for such; and guidelines on the correct employment of these parameters for evaluation of (steady-state) rate and average degree of polymerization.
The previous project in this series, “Critically evaluated termination rate coefficients for free-radical polymerization. 1. Current status, evaluation of experimental methods, data for styrene and methyl methacrylate” (project 2000-028-1-400), was by any measure a success. This message is conveyed most emphatically by the impressive number of citations so far for the two publications from this project: 108 for M. Buback et al. Macromol. Chem. Phys. 2002, 203, 2570-2582 (https://dx.doi.org/10.1002/macp.200290041), and 72 for C. Barner-Kowollik et al. Prog. Polym. Sci. 2005, 30, 605-643 (https://dx.doi.org/10.1016/j.progpolymsci.2005.02.001).
What these figures evidence is the thirst of the radical polymerization (RP) community – including the many practitioners of reversible-deactivation (“living/controlled”) RP – for definitive instruction and data on termination, traditionally the most difficult topic in the realm of RP kinetics. The reason for the difficulty has become incontrovertibly clear over the last decade: termination is chain-length dependent in rate.
Nov 2014 – Project announcement published in Chem. Int. Nov-Dec 2014, p. 20; DOI: 10.1515/ci-2014-0615
Last update 18 Nov 2014