Polylactic acid based biocomposite films reinforced with silanized nanocrystalline cellulose.

Polylactic acid (PLA) and nanocrystalline cellulose (NCC) are promising biodegradable materials that have shown great potential in a wide range of healthcare and packaging applications. In the present work, PLA and NCC were compounded at various ratios to form biocomposite films via solution casting process. In order to improve the compatibility of PLA/NCC blends, the NCC was deliberately subjected to graft modification by 3-aminopropyltriethoxysilane (KH-550). The as-prepared PLA/NCC composite films were further characterized by using SEM, FTIR, X-ray diffraction, UV-visible spectra analysis, thermal analysis, air permeability and mechanical measurements. Results showed that silanized NCC (SNCC) addition had an important effect on the overall properties of PLA based composite films. The increased SNCC was found to impart improvement in air permeability, light resistance, thermal stability and mechanical properties to the PLA based composite films. Particularly, in comparison to the controlled sample, the obtained PLA based composite films with 0.5 wt % SNCC showed increases of 53.87%, 61.46% in the tensile strength and elongation at break, respectively. Moreover, PLA/SNCC composite films exhibited a decrease of 87.9% in air permeability compared with pure PLA film. Therefore, this work may offer an effective route for reinforcing PLA based composite films.