The free-volume theory indicates that under certain condition, the addition of a low molecular weight species will actually slow down mobility in a polymer phase, also known as antiplasticization. Although antiplasticization is a rare phenomenon, it has been reported in the literature. Nevertheless, not all these cases reported have the same origin. As shown in the Annual Progress Report last year antiplasticization can be classified into four categories: I Thermodynamically driven. II Free volume reduction. III Non equilibrium or (glassy state) antiplasticization and, IV Multicomponent. In this work we attempted theoretically and experimentally probe antiplasticization is caused by a decrease of the free volume available in the polymer-solvent system.

I Thermodynamically driven.
II Free volume reduction.
III Non equilibrium or (glassy state) antiplasticization and,
IV Multicomponent.

In this work we attempted theoretically and experimentally probe antiplasticization is caused by a decrease of the free volume available in the polymer-solvent system.