Characterization and fungal biodegradation of Bio-Nano-composite reinforced with unmodified and modified cellulose nanofibers

The aim of this study was to evaluate the effect of chemical modification of cellulose nanofibers (CNF) on physical, mechanical and fungal biodegradation of plasticized starch (PS) bio-composites. Composites were produced using corn starch, glycerol / water as softener and 10% (based on dry weight of both) the original and modified cellulose nanofibers as reinforcement. Successful acetylation of cellulose nanofibers process was conducted using acetic anhydride and pyridine as the catalyst. Water absorption, water vapor permeability, mechanical, dynamic mechanical properties and furthermore, fungal biodegradation of composites were investigated. The results showed that addition of CNF and acetylated cellulose nanofibers (ACNF), resulted in improved mechanical properties of the PS composite and have a significant positive effect on its water absorption. Dynamic mechanical analysis (DMA) showed that the storage modulus significantly improved by addition of cellulose nanofibers. Weight loss measurement was used to evaluate the fungal biodegradation of the nano-composite under various conditions. Obtained results revealed that the effect of addition of both (CNF & ACNF) on the weight loss was significant and increased the bio-degradation period of plasticized starch composite, especially in PS/ACNF nano-composite.