POLYMER-PLASTICIZER INTERACTIONS: COMPARISON OF EXPERIMENTAL DATA WITH THEORETICAL RESULTS

Abstract

In the course of the formulation of coated dosage forms, selection of the suitable composition of the coating system is essential as regards dosage form. Since the systems applied for coating are multicomponent, it is highly important to quantitatively evaluate the possible interactions between the components. These interactions determine the physico-chemical stability of the formulated dosage form, the drug release process and the formulation parameters, as well. In the present study molar refraction values of polymer dispersions were determined for the quantitative estimation of polymer-plasticizer interactions. Dynamic surface tension measurements, differential scanning calorimetry and X-ray diffraction studies were applied to analyse the possible interactions between the polymer and the selected plasticizer. The results indicate that the calculation of molar refraction values of polymer dispersions containing plasticizer offers useful means for the determination of the optimum concentration of the selected plasticizer.