Coating Polymer-plasticizer Interaction in Relation to the Enthalpy Relaxation of Polymer

Abstract

In the course of the formulation of coated dosage forms, the selection of the suitable composition of the coating system is of great importance in respect of the final dosage form. Since the applied coating systems are multicomponent, the possible interactions between the components determine the physico-chemical stability of the formulated dosage form, the drug release process, as well as the formulation parameters. In the present study, the influence of the applied plasticizer, dibutyl sebacate on the enthalpy relaxation of casted Eudragit L 30D films was determined as a function of the plasticizer concentration. The enthalpy relaxation was recorded by DSC during the applied isothermal recovery process of Eudragit films. The obtained results indicate that enthalpy relaxation can be measured by DSC at 20 mass/mass% dibutyl sebacate concentration, which refers to the increased molecular mobility consequently to the effect of the interaction between the polymer and plasticizer.