Nanocelluloses can be used to stabilize oil–water surfaces, forming so-called Pickering emulsions. In this work, we probed the organization of native and mercerized cellulose nanocrystals (CNC-I and CNC-II) adsorbed on the surface of hexadecane droplets dispersed in water by coupling small-angle neutron scattering with contrast variation experiments and molecular dynamics simulations. We showed that there exists a preferred interacting crystalline plane for both allomorphs that exposes the CH groups (100 and 010) and is therefore considered hydrophobic. This study suggests that whatever the allomorph, the migration of CNCs to the interface is spontaneous and irreversible, leading to highly stable emulsions.
Publications: Edge-on (cellulose II) and face-on (cellulose I) adsorption of cellulose nanocrystals at the oil-water interface: a combined entropic and enthalpic process, S. Haouache et al., Biomacromolecules 23 (2022). https://doi.org/10.1021/acs.biomac.2c00201
Cellulose nanocrystals from native and mercerized cotton, S. Haouache et al., Cellulose 29 (2022). https://doi.org/10.1007/s10570-021-04313-8