A Rheological Study of Poly(Vinyl chloride) Plastisols: Investigating the Gel Structure at Room Temperature

The study of the rheology of polyvinyl chloride plastisol is important because, at first, it is in a paste state and is usually applied by spraying. Moreover, controlling the gel and melting processes is possible by using rheology. This research investigated the rheological behavior of plastisols, including shear thinning behavior, thixotropy and gelation behavior. Also, long-term ageing was studied and it was found that plastisols turn into gel at a constant temperature for a long time period according to the concept of time-temperature superposition. Finally, the relationship between the samples' thixotropy and yield stress was evaluated to study the physical gel structure. The results confirm that thixotropy and yield stress in PVC plastisols are the same due to the fundamental physics and this is related to the strength of the microstructure.