Pickering emulsions with stimulable particles: from highly- to weakly-covered interfaces.

We study oil-in-water emulsions stabilised by pH-sensitive colloidal silica or latex particles. Depending on the composition of the continuous phase, the same type of particles and the same emulsification process lead to emulsions characterised either by large drops densely covered by the particles, or to small droplets which are weakly covered. The two kinetically stable states can be tuned reversibly by using pH or salinity as compositional stimuli.