Diffusion and solubility of hazardous compounds in polyvinyl chloride

Polyvinyl chloride (PVC) is a widely used polymer for many types of products, some of which come into close contact with people. To obtain flexibility a variety of plasticizers are added to PVC. Over the years these additives have been investigated extensively in terms of their potential health and safety hazards. The diffusion and solubility of these materials at higher concentrations (10–50 wt%) in PVC have been reported by a number of researchers. Similar data at very low concentrations, however, have not been found. At ambient temperatures the diffusivity is so low that direct measurements are very difficult if not impossible. In this study data at higher temperatures have been obtained, compared with predictions or correlated with a model, and then extrapolated to ambient conditions. This provides some reasonable estimates of the solubility and diffusivity that can be expected at the lower limits of concentration, low temperature, and atmospheric pressure.