Surfactant-Assisted Poly(lactic acid)/Cellulose Nanocrystal Bionanocomposite for Potential Application in Paper Coating

Abstract

The current article addresses a new strategy for the preparation of polylactic acid/cellulose nanocrystal (P LA/CNCs) nanobiocomposite films with improved structural morphology, mechanical and barrier properties for food packaging applications. The addition of hexadecyltrimethylammonium bromide (CTAB) and sodium lauryl sulfate (SLS) as cationic and anionic surfactants respectively, was found to play a crucial role in preventing re-aggregation of the CNCs during drying and improving the dispersion of CNCs in the PLA. The coated paper was characterized using mechanical tests, water vapor permeability (WVP), X-ray diffraction (XRD), scanning electron microscopy (SEM) and air permeability. The results showed that the paper coated with PLA containing 7.5% CNCs and 0.15% CTAB based on weight of PLA, gives the highest measured paper properties, where an increase in tensile strength (+133%), Young's modulus (+309%), tear index (+183%), burst (+60.8) and a decrease in air permeability (-92%) was obtained.