THERMAL-STABILITY OF POLY(VINYL CHLORIDE) IN BLENDS WITH POLYETHYLENEIN SOLUTIONS

Liquid-phase degradation of PVC blended with PE was examined. In solut ions in 1,2,3-trichloropropane and 1,2,4-trichlorobenzene, the rate of thermal degradation of PVC blended with PE rises with an increase in PE content in the blend, as compared to the rate of dehydrochlorinatio n of pure PVC in these solvents. In cyclohexanol, however, it decrease s, while in coprecipitated PVC/PE powders, the latter component has no effect on thermal stability of PVC. The effect of PE on the thermal s tability of PVC is essentially dependent on the physical state of PVC in the polymer blend (presence or absence of a solvent) and on the nat ure of solvent, in the case of liquid-phase degradation.