LAUSR

This study reports for the first time, a green process to fabricate Lyocell fiber and graphene oxide (GO) based novel cellulose/graphene oxide nanocomposite (CGN) flexible films for ultraviolet (UV) shielding applications. Polyethelene glycol (PEG) mediated solvent system was utilized to make CGN films via solution casting route. To improve the dispersion of GO sheets in cellulosic matrix, a reactive interface was formed in-between cellulose and oxygenic functionalized groups of GO sheets via crosslinking them with epichlorohydrin (ECH). The addition of GO sheets in cellulose matrix leads to the synergistic changes, which were observed in the structure and surface morphology of CGN nanocomposite films. Enhanced dispersion of GO sheets in CGN films was observed in morphological investigations which is attributed to the adequate cellulose-GO interaction by hydrogen bonding, led to significant enhancement in mechanical and thermal properties. The tensile strength and Young's modulus of CGN films with 2wt% GO loading (CGN2) increased to 89 MPa and 4.3 GPa from 55.6 MPa and 2.1 GPa, respectively as compared to neat cellulosic film. Additionally, the CGN films exhibited remarkable UV shielding capability which increased with GO loading in cellulose matrix. The CGN2 film (2wt% GO loading) possessed outstanding absorbance in the wave-length range of 280 nm to 400 nm, showed almost complete shielding (~99%) of UV rays both in UV-B and UV-A region. Moreover, the ultraviolet protection factor (UPF) of CGN2 film demonstrated more than eighty fold increase in comparison to neat cellulose (NC) film. The obtained CGN nanocomposite film has a high potential for applications in the field of UV protection.