Preparation and Characterization of Cellulose Nanocrystals from Bamboo Pulp

Cellulose nanocrystals (CNCs) can be obtained from bamboo pulp by hydrolysis with sulfuric acid. Firstly, the authors conducted a series of experiments under different conditions, and concluded that the optimal parameters were as follows: sulfuric acid concentration 60%, temperature 45 °C, the time is 90 minutes and the solid-liquid ratio is 1:8. Then, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TG) were employed to characterize and test the morphology, structure and thermal stability of the CNCs obtained under the optimal conditions. It was found that CNCs mainly exist in two forms, as a rod network and as a porous network, and they have the basic chemical structure of cellulose, while the hydrogen bonds are destroyed. Compared with bamboo pulp, the degree of crystallinity of CNCs is obviously improved, but the thermal stability is weakened.