Carboxylated cellulose nanofibrils from sugarcane bagasse as stabilizers for Pickering emulsions

Bagasse is the primary by-product of the sugarcane industry. To enhance the utilization of bagasse, cellulose was extracted and subsequently transformed into carboxylated cellulose nanofibers (CCN) through a series of alkalization and esterification reactions. The obtained CCN were then employed as stabilizers for Pickering emulsions. Fourier transform infrared and X-ray diffraction analyses confirmed the successful introduction of -COO-Na + groups while retaining the structure of cellulose. Contact angle measurement revealed that the contact angle of CCN was 72.6 ± 2.5°, suggesting its potential for stabilizing oil-in-water Pickering emulsions. Confocal laser scanning microscopy indicated that as the CCN concentration increased from 0.3 g/100g to 1.2 g/100g, the size of the emulsion droplets decreased from 8.26 ± 0.27 μm to 7.48 ± 0.24 μm. The emulsion stabilized with a CCN concentration of 1.2 g/100g remained stable after 30 days of storage. Moreover, the emulsion exhibited stability in an alkaline environment (pH = 9), with droplet sizes measuring 4.64 ± 0.21 μm, and it too remained stable after 30 days. In summary, this study demonstrates that CCN derived from bagasse possesses excellent emulsifying properties, and the resulting emulsions exhibit significant environmental stability. • Cellulose extracted from bagasse was modified through introduction of carboxyl groups and Na + . • Carboxylated modification enhanced the storage stability of the cellulose emulsion. • Modified cellulose emulsion demonstrates excellent stability in high pH environments.