Simultaneous enhancement of the strength and the roughness of poly(lactic acid) using palmitoylated cellulose nanocrystal

The nanocomposite films from poly(lactic acid) (PLA) and palmitoylated cellulose nanocrystals (e-CNCs) were characterized using different techniques. Raman spectra showed the formation of hydrogen bonding interactions between the PLA and the e-CNCs. The proper amount (1.0 wt%) of the e-CNCs led to the formation of greater amounts of smaller PLA spherulites and increased the PLA crystallinity in comparison with the neat PLA sample. The scanning and transmission electron microscopy images showed that 1.0 wt% of the e-CNCs could uniformly be dispersed in the PLA matrix and that the nanocomposite exhibited some elasticity. The dynamic rheological properties showed the formation of interconnected networks in the PLA/e-CNCs composite at 1.0 wt% of the e-CNCs. The analysis of the mechanical performance of the ensuing nanocomposite showed a 74% increase in tensile strength, a 62.1% increase in Young's modulus, and a 68.4% increase in the elongation at the break after the incorporation of 1.0 wt% of the e-CNCs into the PLA. Therefore, the palmitoylated CNCs were highly promising for the simultaneous enhancement in the strength and the toughness of PLA.