RHEOLOGY OF PLASTISOLS OF POLY(VINYL-CHLORIDE)

A plastisol is a system containing fine particles of poly(vinyl chloride) (PVC) dispersed in a plasticizer. The main advantage of plastisols over standard PVC is that the molding or coating of articles can be done at or near room temperature, thereby reducing the operating cost of fabrication. The only high temperature needed is during the relatively short (1-5 min) heating cycle for fusing the plastisol into a homogeneous film or article. This review paper is presented in four parts: (1) introduction; (2) rheological properties of suspensions; (3) rheological properties of PVC plastisols (concentration, particle size and size distribution, effect of plasticizer type, effect of additives, effect of temperature); (4) conclusion. Viscosity is the most important parameter in processing of PVC plastisol. It is postulated that in future work, particular emphasis needs to be given to the understanding of the basic mechanism involved in the effect of additives on the flow behavior. Systematic experiments with a range of well-defined particle sizes and over a wide range of shear rates are also needed.