ABSTRACT: A novel, simple and totally recyclable method has been developed for the synthesis of nontoxic,biocompatible and biodegradable bio-composite films from soy protein and silk protein. Bio films are defined asflexible films prepared from biological materials such as protein. These materials have potential application in medicaland food as a packaging material. Their use depends on various parameters such as mechanical (strength andmodulus), thermal, among others. In this study, prepare and characterization of bio films made from Soy ProteinIsolate (SPI) (matrix) and Silk Fiber (SF) (reinforcement) through solution casting method by the addition ofplasticizer and crosslinking agent. The obtained SPI and SPI/SF composites were subsequently subjected to evaluatetheir mechanical and thermal properties by using Universal Testing Machine and Thermal Gravimetric Analyzerrespectively. The tensile testing showed significant improvements in strength with increasing amount of SF contentand the % elongation at break of the composites of the SPI/SF was lower than that of the matrix. Though theinterfacial bonding was moderate, the improvement in tensile strength and modulus was attributed to the highertensile properties of the silk fiber.

Keywords: Bio films, Soy protein isolate, Silk fiber, Tensile properties, Thermal stability, Interfacial bonding