Study of Butyl Methacrylate Depropagation Behavior Using Batch Experiments in Combination with Modeling

Batch polymerization experiments are combined with simulations to investigate the depropagation behavior of butyl methacrylate (BMA). Experiments carried out between 110 and 145 degrees C and polymer contents between 9 and 34 wt %, including experiments conducted with added polymer, indicate that equilibrium monomer concentration ([M](eq)) varies not only with temperature but also with polymer content. An extended Predici model provides a good fit to the monomer concentration and polymer molecular weight profiles, with the simulated monomer profiles at 132 and 145 degrees C sensitive to small changes in the depropagation activation energy. Thus, these data provide a better estimate of depropagation kinetics than those measured by the pulsed-laser polymerization/size-exclusion chromatography method. The entire data set is well-represented by [M](eq) (mol center dot L-1) = 1.76 x 10(6)(1 - 0.778x(wp)) exp(-6240/T), in which x(wp) represents the weight fraction of polymer in the system.