Schrooten, J.; Buback, M.; Hesse, P.; Hutchinson, R. A.; Lacík, I.
Termination Kinetics of 1-Vinylpyrrolidin-2-one Radical Polymerization in Aqueous Solution
Macromolecular Chemistry and Physics 2011, 212, 1400-1409.
 

Termination kinetics of 1-vinylpyrrolidin-2-one radical polymerization in aqueous solution has been studied at 40 °C between 20 and 100 wt.-% VP. The ⟨kt⟩/kp values from laser single-pulse experiments with microsecond time-resolved NIR detection of monomer conversion, in conjunction with kp from literature, yield chain-length-averaged termination rate coefficients, ⟨kt⟩. Because of better signal-to-noise quality, experiments were carried out at 2 000 bar, but also at 1 500, 1 000, and 500 bar, thus allowing for estimates of ⟨kt⟩ at ambient pressure. The dependence of ⟨kt⟩ on monomer conversion indicates initial control by segmental diffusion followed by translational diffusion and finally reaction diffusion control. To assist the kinetic studies, viscosities of VP-water mixtures at ambient pressure have been determined.