Preparation and characterization of silk fibroin-polyvinyl alcohol (PVA) blend films for food packaging materials

The present research work deals with the characterization of blend films obtained by mixing silk fibroin (SF) [Bombyx mori CSR4] and Poly Vinyl Alcohol (PVA) in various proportions, considering its potential applicability in the food-packaging industry. The structural, chemical, mechanical and thermal property as well as surface morphologies of blend films were investigated by X-ray diffraction (XRD), Fourier transform InfraRed spectroscopy, universal testing machine, thermogravimetric analysis, differential scanning calorimetry and scanning electron microscope. The SEM results clearly show the proper miscibility of SF and PVA molecules to give a uniform nice surface to the blend films. The physical and thermal properties of the blend films are enhanced significantly compared to the pure silk fibroin films, with more than 100 percentage elongation at break for few blend films. The SF-PVA blend films are more flexible and thermally stable, and hence a good candidate for food packaging material.