Aqueous solutions of hydroxypropyl cellulose, Tween 80 and their binary mixtures: Colloid-chemical aspects

Abstract

Tensiometry, dynamic light scattering, and rheology have been used to study the colloid-chemical properties of hydroxypropyl cellulose, Tween 80, and binary mixtures thereof in an aqueous medium and at water/decane and water/air interfaces. The efficiency of a reduction in the interfacial energy under dynamic and static conditions, the surface activity of the components, capability of self-organization in bulk and at interfaces, as well as emulsifying efficiency of the systems, have been analyzed. It has been found that, in a narrow concentration range and at a certain ratio of the components, they exhibit a synergetic effect with respect to a reduction in the interfacial energy, with this effect being due to the formation of a Tween 80–polymer bilayer via hydrogen bonding between hydroxyl groups of hydroxypropyl cellulose and ethoxy units of Tween 80.