CHARACTERIZATION AND DEGRADATION STUDIES OF SUSPENSION-POLYMERIZED POLY(VINYL CHLORIDE) .1. THERMAL-DEGRADATION

The degradation behaviour of three suspension type poly(vinyl chloride) (PVC) resins was examined using UV-visible and IR spectroscopies, viscometry and thermal analysis. Both thermal and thermo-oxidative degradation characteristics were studied. Characterization of the resins showed the presence of residues from additives added during the polymerization stage. Although the lowest molecular weight resin showed the highest thermal stability, the results indicate that the presence of polymerization residues has a more significant effect on the degradation behaviour of the samples under investigation. The results differ from published data, which attribute differences observed in the degradation behaviour of PVC samples to molecular defects.