Increasing environmental awareness is prompting researchers and industrialists to develop strategies for environmental sustainability by using processes and materials with low cost, energy consumption and toxicity. As an example, emulsions, used in large application domains such as cosmetics, pharmaceuticals… usually use surfactants issued from the petro-chemical industry.
Pickering emulsions for which colloidal-sized particles
In this framework, it is now well established that surfactant free can be stabilized by dispersed solid particles to form the so-called Pickering emulsions for which colloidal-sized particles may be irreversibly anchored at the oil/water interface revealing a very high emulsion stability. Yet, it was demonstrated in our team that direct oil-in-water (O/W) Pickering emulsions can be stabilized only by negatively charged Cellulose Nanocrystals (CNC) or positively charged Chitin Nanocrystals (ChNC).
In this study, two series of O/W emulsions stabilized by the two different types of solid nanoparticules (cellulose and chitin nanocrystals) were prepared. A dye (paprika) was dissolved in the oil phase. The control of the dye release has been monitored by modification of the droplets surface making the wall of the droplets thicker.