Tuning the cellulose nanocrystal alignments for supramolecular assembly of chiral nematic films with highly efficient UVB shielding capability

摘要: The exploration of clean and sustainable cellulose based films with ultraviolet (UV) shielding capabilities has gained considerable attention due to the current situation ozone layer damage potential risk skin cancer, mostly caused by radiation from UVB region (wavelength: 280–320 nm). In present work, nanocrystal (CNC) a characterized chiral nematic structure were used for first time fabricate UV materials facile convenient esterification salicylic acid (SA) p-aminobenzoic (PABA). prepared perfect UVB-shielding properties 99.7% an ordered cholesteric organization showing birefringence after evaporation induced self-assembly. Xylose (Xyl) that is eco-friendly can be simply derived lignocellulose was introduced tuning supramolecular alignments CNC composite films. mechanical strength CNSP-X5 film improved up 70.5 MPa together higher transparency flexibility increased amount Xyl. Interestingly, satisfying performances well retained (∼99%) Xyl adjustments, which explained stabilized dual intermolecular hydrogen-bonding linkages between both SP CNC. Meanwhile, interactions also aggregation nanoparticles during evaporation, gradually generating more isotropic orientation dried weakening iridescence observed under polarized light. CNC/SA/PABA obtained multi-functions via tuning, thus high producing applicable protective monitoring sensors, anti-counterfeiting devices as surface coating composites vehicles.