Bifunctional Reinforcement of Green Biopolymer Packaging Nanocomposites with Natural Cellulose Nanocrystal–Rosin Hybrids
Fang Li, Somia Yassin Hussain Abdalkarim, Hou‐Yong Yu, Jiaying Zhu, Ying Zhou, Ying Guan
Abstract
Rosin and cellulose nanocrystals (CNCs) are easily extracted from agricultural pines/conifers and natural cellulose, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is extracted from agricultural corn stalks, etc. In this study, PHBV and CNC-grafted rosin (CNC-R) hybrids were successfully fabricated by an efficient solution casting. The nanocomposites with a homogenous microstructure were transparent and had strong barrier resistances to water vapor and two food simulants. The synchronous enchantments in mechanical strength/toughness and thermal stability of nanocomposite films were achieved by addition of CNC-R. The T0 increased by 31.2 °C for the film with 10 wt % CNC-R; meanwhile, the tensile strength and elongation to break were improved by 107.9 and 43.9% for the sample using 5 wt % CNC-R, respectively. Also, compared to neat PHBV, the nanocomposites with 5 wt % CNC-R exhibited excellent barrier properties, antibacterial activity (100.0% antibacterial ratio), and lower migration levels for both food simulants. The appearance of coated grapes with 10 wt % CNC-R nanocomposites at the 11th day was the best compared to those of PHBV and its nanocomposites with a low CNC-R content (1–3 wt %). Thus, our nanocomposites with CNC-R showed a significant application in packaged grape by extended shelf life and had potential applications in bioactive food packaging materials.