Abstract
By choosing the convenient surfactant and by adjusting the molar ratio surfactant/polyelectrolyte, it is possible to precipitate a polyelectrolyte on the surface of oil droplets by complex coacervation. The resulting insoluble surfactant/polyelectrolyte complex (SPEC) could be the membrane of the microstructured complexes and hydrophobic substances could be solubilized into the hydrophobic core. In this study, three polyelectrolyte/surfactant systems, being able to form the wall of the microcapsules, are investigated. The anionic surfactant is Sodium dodecylsulfate (SDS) and the choosen polymers are polysaccharide chitosan, hydrophobically modified chitosan and type A gelatin (protein). Physical and hydrophobic interactions (in absence of salt) between these various polyelectrolytes and the surfactant are characterized by isothermal titration calorimetry, tensiometry, conductimetry,viscosimetry, electrophoretic measurements and determination of the binding isotherms.