Nanocomposite Film of Recycled Silk Powder and Polypropylene

In this study, the possibility of producing silk nanopowder by a commercial proteolytic enzyme in combination with a mechanical treatment is investigated. Different conditions are applied in order to investigate the effects of enzyme concentration and treatment time. The SEM photographs show that the particle size of the produced silk powder is mostly less than 100 nm. The prepared powder is then blended with polypropylene (PP) in different percentages for producing composite films. The SEM micrographs indicate that silk nanoparticles distributed uniformly in the film. Characteristic peaks of both silk and PP are found in FTIR spectra and thus no obvious chemical changes occur during the blending. With the increase in the ratio of the silk powder, there is an evident decrease in the tensile strength and elongation at break. However, silk powder plays an important role in improving the moisture absorption of the films