Propagation rate coefficient for acrylic acid polymerization in bulk and in propionic acid by the PLP–SEC method: experiment and 3D simulation

Abstract

The propagation rate coefficient (k_p) plays a crucial role in the kinetics of radical polymerization. In this study, k_p values are determined for the polymerization of acrylic acid (AA) in bulk as well as in its saturated analogue, propionic acid (PA), at 25 °C by the pulsed-laser polymerization–size-exclusion chromatography method (PLP–SEC). The k_p values for AA are found to depend on the number of pulses used in the PLP experiment. The 3D simulation reveals that this dependency is partially attributed to the increase in temperature due to the heat release during polymerization with increasing conversion. A 3D simulation-based procedure is developed to recommend the PLP conditions providing the k_p values free from this dependence. Interestingly, the k_p values determined for the polymerization of AA in PA increase with the AA content.