The mixture of poly(propylene-glycol)-block-poly(ethylene-glycol)-block-PPG with C₁₂E₅ microemulsion

Abstract

We study oil-in-water microemulsions, in particular dispersions of n-decane droplets coated with a monolayer of the surfactant C₁₂E₅ in a continuous phase of water. Upon addition of the tri-block poly(propylene-glycol)(PPG)-block-Poly(ethylene-glycol)(PEG)-block-PPG, the depletion interaction between the oil droplets of microemulsion is induced. At constant droplet size, we vary the polymer concentration and there is clear evidence for an increasing depletion interaction of the droplets from structural investigations with small-angle x-ray scattering and photon correlation spectroscopy (PCS). Our results show that the PEG does increase the depletion interaction more than the tri-block PPG-PEG-PPG.

Keywords:

• light scattering
• SAXS
• microemulsion
• nano-droplet