The Effect of Antimony Trioxide on the Pyrolysis of Styrenic Polymers

Abstract

Brominated high impact polystyrene (Br-HIPS) which contained either 5% or 0% antimony trioxide (Sb2O3) and either decabromodiphenyl ether (DDO) or decabro-modiphenyl ethane (DDE) was pyrolysed in a fixed bed reactor at 430°C. The effect of Sb2O3 on the pyrolysis of HIPS-Br polymers and the effect of different types of bromi-nated flame retardants (BFRs) used in polystyrene plastics has been studied. The pyro-lysis oils were characterised using GC-MS, GC-FID, FT-IR, GC-AED and GC-ECD. The plastics without Sb2O3 produced mainly toluene, ethylbenzene, styrene, cumene, and alpha-methyl styrene and with Sb2O3 sample oils did not contain any styrene or alpha-methyl styrene, but instead contained greater concentrations of ethylbenzene and cumene. Analysis of the Br-HIPS + polyolefin co-pyrolysis products showed that the presence of polyolefins led to an increase in the concentration of alkyl and vinyl mono-substituted benzene rings in the pyrolysis oil/wax resulting from Br-HIPS pyrolysis.