CONTRIBUTION TO THE MODELING OF PREDEPOLYMERIZATION OF POLYSTYRENE

To optimize the experimental conditions for the recycling of plastic w astes, we modeled the thermal degradation process of a standard polyst yrene, having a low polydispersity index. The number of initial ruptur es, N-o in the macromolecular chain during the pyrolysis at 350 degree s C under nitrogen pressure is determined from the gel permeation chro matography results from the experiments with tetralin as the hydrogen donor solvent, assuming that all radicals have been stabilized by this solvent. The calculation shows that there are 23 depropagation reacti ons, 40 intramolecular transfers, and for n intermolecular transfers, n - 2 recombinations, and N-o - n + 2 dismutations. (C) 1996 John Wile y & Sons, Inc.