Two characteristic cellulose nanocrystals (CNCs) obtained from oxalic acid and sulfuric acid processing

Abstract We systematically compare the different properties of cellulose nanocrystals (CNCs) obtained by oxalic acid and sulfuric acid hydrolysis methods. The variant characteristics of two kinds of CNCs were confirmed by XRD, DLS, Zeta, TGA, and SEM techniques. When CNCs were mixed with PEG, and the chiral nematic tissue of CNCs was retained in the solid film to observe the liquid crystal phase by evaporation-induced self-assembly. The brilliant snowflake-like pattern of CNC film was observed through oxalic acid instead of sulfuric acid. More importantly, carboxylated CNCs prepared by oxalic acid was easily formed a liquid crystal phase by adding cationic solutions into 1.27% CNC solution. The extra properties of CNCs obtained by oxalate dihydrate contribute to its potential application prospects in optical devices and chiral separation. Graphic abstract