Further Studies on the Softening of Rigid PVC by Aqueous Solutions of Organic Solvents.

: In this study, small pieces of PVC well casing were exposed to relatively low activities (or relative solubilities) of TCE and methylene chloride for 12 months. PVC pieces were also exposed to aqueous solutions containing several organic chemicals that were either solvents or swelling agents of PVC. In addition, small pieces of PVC were exposed to aqueous solutions containing organic chemicals that were either PVC solvents or swelling agents and were totally miscible in water. These studies revealed that there is an interactive effect among these chemicals when dissolved in water. However, softening does not appear to occur in any solutions where the sum of the relative solubilities is less than 0.1.