Binary mixture pyrolysis of polystyrene and poly(α-methylstyrene)

The batch pyrolysis of polystyrene (PS) in the presence of poly(α-methylstyrene) (PAMS) was investigated to determine the effect of the second polymer on the decomposition of polystyrene. Experimental parameters that were varied included the molecular weight and the concentration of each polymeric reactant. It was observed that the decomposition of polystyrene was dependent on the molecular weight of poly(α-methylstyrene). An enhancement in the polystyrene degradation rate was achieved during binary mixture pyrolysis of low molecular weight polymers, but a rate inhibition was observed during degradation in the presence of higher molecular weight PAMS. It is proposed that the divergence arises from differences in the relative magnitude of the enhancement caused by the production of PAMS-derived radicals and the inhibition due to incorporation of α-methylstyrene monomer into depolymerizing polystyrene chains. Variations in the initial concentration of the reactants had little effect on the yields of polystyrene degradation products.