Bulk polymerization of methyl methacrylate: Part I: some kinetic and modelling considerations for isothermal reactions

Abstract

Kinetic studies of the bulk polymerization of methyl methacrylate have been carried out by differential scanning calorimetry (d.s.c.) and also by monitoring, gel permeation chromatography (g.p.c.). The residual monomer content in polymerizations was carried out in small thin-walled glass ampoules. Discrepancies have been found between the data acquired by the two experimental methods. These can be resolved by consideration of the measured temperature rise of the polymerizations (which can be up to 80 K above the bath temperature for a 5 g sample) carried out in the ampoules. Comparisons between the kinetic data obtained in these experiments with published data show that many of the reported kinetic constants for this polymerization are probably inaccurate because they were acquired under experimental conditions which may not have been isothermal. The implications of using inaccurate kinetic constants for the computer simulation of the high-conversion polymerization of methyl methacrylate are considered.