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Poly(vinyl alcohol)/ methyl cellulose (PVA/MC) blends, at different ratios were prepared into films by solution casting using, water as a common solvent, and gamma irradiated at various doses. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to study the thermal properties of gamma irradiated PVA/MC blends. It is expected that these methods would enable to understand the effect of gamma irradiation on the mechanism of thermal decomposition. The kinetic parameters such as energy of activation (E a) and regression r 2 for the thermal decomposition were determined by three different methods. In the present work, the Coats-Redfern, Broido and Horowitz-Metzger methods were applied. The results indicated that the E a and r 2 values of the gamma irradiated PVA/MC blends as determined by the three methods were comparable.

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In this work, polymer blends based on poly(vinyl alcohol) (PVA) and different ratios (5 and 10 wt%) of methylcellulose (MC) were prepared into films by solution casting using water as a common solvent, and gamma irradiated at different doses. The blends before and after gamma irradiation were loaded with Doxycycline hyclate (DOX-h) as drug model. The effect of DOX-h drug on the chemical and physical properties was first investigated in terms of gel content, swelling and surface morphology by scanning electron microscopy (SEM). The gamma irradiated PVA/MC blends was evaluated for the possible use in drug delivery systems. In this respect, the release profiles of DOX-h from PVA/MC were investigated. It was found that the accumulated drug release from the blends increases with time to reach ~60% after 1 h at pH of 2 compared to ~100% at pH of 8.