Structural Changes Undergone During Thermal Aging and/or Processing of Unstabilized, Dry-blend and Rigid PVC, Investigated by FTIR-ATR and Curve Fitting

Thermal aging below the glass transition temperature (Tg), during three months, of Poly (vinyl chloride) (PVC) under its three different aspects, powder (p-PVC), dry-blend and Unplasticized (u-PVC) or rigid form was performed. The stabilizing system used is a commercial compound constituted by lead based stabilizers, internal and external lubricants. The ageing of PVC under these three different aspects was performed in a thermo-regulated oven at 60 degrees C, temperature close of the ground temperature in Sub-Sahara region (Ghardaia, Algeria). A sampling at regular interval allowed following the microstructural changes undergone by these materials. Such an approach revealed that the additives used in the PVC recipe not only assist processing but also ensured a good material stabilization when thermal aged. The results obtain can help producers to modify the PVC recipe to improve the heat resistance of the PVC tubes to make them more performing in the very hot and deleterious Saharan environment.