Some modification of cellulose nanocrystals for functional Pickering emulsions.
Cellulose nanocrystals (CNCs) are negatively charged colloidal particles well known to form highly stable surfactant-free Pickering emulsions. These particles can vary in surface charge density depending on their preparation by acid hydrolysis or applying post-treatments. CNCs with three different surface charge densities were prepared corresponding to 0.08, 0.16 and 0.64 e nm(-2), respectively. Post-treatment might also increase the surface charge density. The well-known TEMPO-mediated oxidation substitutes C6-hydroxyl groups by C6-carboxyl groups on the surface. We report that these different modified CNCs lead to stable oil-in-water emulsions. TEMPO-oxidized CNC might be the basis of further modifications. It is shown that they can, for example, lead to hydrophobic CNCs with a simple method using quaternary ammonium salts that allow producing inverse water-in-oil emulsions. Different from CNC modification before emulsification, modification can be carried out on the droplets after emulsification. This way allows preparing functional capsules according to the layer-by-layer process. As a result, it is demonstrated here the large range of use of these biobased rod-like nanoparticles, extending therefore their potential use to highly sophisticated formulations.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'.
UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France.
Dorra
D
Saidane
UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France.
Emilie
E
Perrin
UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France.
Fanch
F
Cherhal
UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France.
Florian
F
Guellec
UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France isabelle.capron@nantes.inra.fr.
Isabelle
http://orcid.org/0000-0001-9145-3803
I
Capron
D002482:Cellulose / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D013499:Surface Properties
D004655:Emulsions; D002482:Cellulose
capsule; cellulose nanocrystal; colloidal particle; functional emulsion; layer-by-layer; nanorod