Inhomogeneity during the bulk polymerisation of divinyl compounds: Differential scanning calorimetry experiments and percolation theory

Abstract

AbstractExperiments are presented that indicate inhomogeneity in bulk divinyl polymerisation which persists far beyond the gel point and a percolation model is given by which this inhomogeneity is simulated. Isothermal differential scanning calorimetry experiments indicate trapping of radicals in regions of low mobility long before overall vitrification occurs. The results on pendant double bonds in divinyl polymerisation are similar to those obtained by Malinsky et al. for styrene/divinyl benzene copolymerisation. The percolation model used shows inhomogeneity in snapshots and provides a qualitatively correct description of the high extent of cyclisation at low conversion, in contrast to classical chemical kinetics. The model overestimates the crosslinking at high conversion.