"Sponge" effects in the interaction of polymers with low-molecular-mass compounds

Anomalous properties of PMMA or CTA films containing dibutyl phthalate and naphthalene, which are unusual from the standpoint of homogeneous blends, w ere observed. Despite close values of the solubility parameters of the poly mers and the low-molecular-mass compounds, the films of ternary blends exhi bit accelerated desorption of one of the two low-molecular-mass components, thus showing evidence of competition between them for adsorption sites in the macromolecular-chain sponge of polymer matrix. The competition reflects the entropy mechanism of reorganization of the macromolecular-chain sponge into a microporous adsorbent, during which a low-molecular-mass compound h aving a higher vapor pressure acts as a displacing agent. The structural tr ansition from macromolecular-chain sponge to microporous adsorbent is confi rmed by calculations of the sorption isotherms of the low-molecular-mass co mpounds, based on the results of measurements in the osmotic equilibrium st ate, which fully conform to equations of the theory of bulk filling of micr opores.