Evaluation of PVC Geomembrane Shrinkage Due to Plasticizer Loss

When plasticizer migrates out of a polyvinyl chloride (PVC) geomembrane, the geomembrane shrinks. This paper presents equations that give the changes in volume and dimensions of the geomembrane as a function of the plasticizer content before and after shrinkage. A second series of equations is presented, which gives the changes in volume and dimensions of the geomembrane as a function of the plasticizer loss ratio. These equations depend on the densities of constituents of the geomembrane. However, approximate equations that do not depend on those densities are presented.