Miscibility of eudragit/chitosan polymer blend in water determined by physical property measurements

The interest in the preparation and application of polymeric blends is growing since they can exhibit properties of great industrial interest. The current study focuses on the preparation of polymeric blends of varying compositions of eudragit and chitosan and their miscibility studies. The preparation was carried out by using ethanol and 1% acetic acid in water. FT-IR spectra reveal the possibilities of chemical interactions between eudragit/chitosan. The miscibility of polymeric blend at different composition has been investigated by viscosity, ultrasonic velocity, density, refractive index and adiabatic compressibility values measured at two different temperatures 30 degrees C and 40 degrees C. The interaction parameters Delta B, mu and alpha, were determined from viscosity data. From the values observed, it is found that the blend is miscible in all compositions at 30 degrees C whereas at 40 degrees C, it seems to be immiscible in certain compositions. It is found that the blend is miscible, when the chitosan concentration is more than 70% (v/v) at both the temperatures and also observed that variation of temperature has no effect on the miscibility of eudragit/chitosan blend. (C) 2012 Elsevier B.V. All rights reserved.