Miscibility Studies of Polysaccharide Xanthan Gum/PVP Blend

Miscibility characteristics of Xanthan gum and Poly (vinyl pyrrolidone) (PVP) in common solvent water were studied by viscometry, ultrasonic velocity and density techniques at 30 and 50 A degrees C. Blend films of Xanthan gum/PVP were prepared by solution casting method and characterized by scanning electron microscopic (SEM) and differential scanning calorimeter (DSC) techniques. Using the viscosity data, interaction parameters of Chee's (mu) and Sun's (alpha) were computed to determine their miscibility. The values obtained revealed that blends were miscible when PVP content is up to 70% in blend at 30 A degrees C. Xanthan gum/poly (vinyl pyrrolidone) blends showed miscibility in all composition at 50 A degrees C. The results were then confirmed by ultrasonic velocity, density, and DSC techniques. Compatibility in the above compositions may be due to the formation of hydrogen bonding between the carbonyl group in PVP and hydroxyl group in Xanthan gum. Further, the results revealed that change in temperature had significant effect on the miscibility of Xanthan gum/Poly (vinyl pyrrolidone) blends.