The thermal degradation of poly(vinyl acetate) (PVAc) was carried out in the presence of various concentrations of aluminum chloride (AlCl3) at different temperatures. The time evolution of molecular weight distributions (MWDs) was determined by gel permeation chromatography. A continuous distribution kinetic model was used to evaluate the degradation rate coefficient assuming the reaction is first order in polymer concentration and that the decomposition of AlCl3 is first order. Experimental data indicated that the presence of AlCl3 greatly enhanced the rate of degradation of PVAc. The activation energy of the degradation rate coefficient for PVAc in presence of aluminium chloride was 14.2 kcal/mol. © 2001 Elsevier Science Ltd.