Sheet-like Cellulose Nanocrystal-ZnO Nanohybrids as Multifunctional Reinforcing Agents in Biopolyester Composite Nanofibers with Ultrahigh UV-Shielding and Antibacterial Performances.

The uses of inorganic metal oxide and ZnO nanohybrids as UV absorbers have potential to increase the production of UV-protective textile, which will also overcome the drawbacks of organic molecules and prevent negative impacts on human health and environment. In this work, sheet-like cellulose nanocrystal-ZnO (CNC-ZnO) nanohybrid was successfully developed by one-step hydrothermal method. The obtained CNC-ZnO nanohybrids as UV absorber and antibacterial agents were introduced into biopolyester (poly(3-hydroxybutyrate- co -3-hydroxy valerate, PHBV) by using electrospinning process. The addition of sheet-like CNC-ZnO can greatly enhance PHBV thermal stability and crystallization ability. In addition, excellent antimicrobial ratios of Escherichia coli and Staphylococcus aureus and high absorbency of solution A (9.82 g/g) were obtained for the composite nanofibers with 5 wt % CNC-ZnO. Moreover, most of the UV irradiations were blocked out for both UVA (99.72%) and UVB (99. 95%) with high UPF value of 1674.9 in the resulting composite nanofibers with 9 wt % CNC-ZnO. This study provides a novel method to produce sheet-like CNC-ZnO with multifunctional properties and its nanocomposite for potential uses as wound dressings and other functional biomaterials.