Stabilizing both oil droplets and titanium dioxide nanoparticles in aqueous dispersion with nanofibrillated cellulose

Author(s)

Silva, Caroline E. P. ; Bernardes, Juliana S. ; Loh, Watson

• Document type: Journal article
• Source: Carbohydrate Polymers; v. 302, p. 11-pg., 2023-02-15.

Abstract

Nanocellulose is a well-known stabilizer for several colloidal dispersions, including emulsions and solid nano -particles, replacing surfactants, polymers, and other additives, and therefore providing more minimalistic and eco-friendly formulations. However, could this ability be extended to stabilize oil droplets and inorganic nanoparticles simultaneously in the same colloidal system? This work aimed to answer this question. We eval-uated both cationic and anionic nanofibrillated celluloses to stabilize both titanium dioxide nanoparticles and oil droplets. The resulting suspensions held their macroscopic stability for up to 2 months, regardless of pH or surface charge. Cryo-TEM images revealed a complex network formation involving nanofibers and TiO2 nano -particles, which agrees with the high viscosity values and gel-like behavior found in rheology measurements. We propose that the formation of this network is responsible for the simultaneous stabilization of oil droplets and TiO2 nanoparticles, and that this may be used as a formulation tool for other complex systems. (AU)

• FAPESP's process: 16/04514-7 - Cellulose nanoparticles as rheology modifiers for complex fluids
• Grantee: Juliana da Silva Bernardes
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• FAPESP's process: 15/25406-5 - Organizing matter: colloids formed by association of surfactants, polymers and nanoparticles
• Grantee: Watson Loh
• Support Opportunities: Research Projects - Thematic Grants