Determination of the surface energy of clay—organic complexes by contact angle measurements

Abstract

Surface energies of montmorillonite—alkylammonium complexes were determined from contact angle measurements performed using the two-liquid phase method. An apparent surface energy ⇐ a (with ⇐ a=⇐ a P+⇐ a D) was determined for partially hydrated surfaces. When the length of the organic ion increases, that is to say when the part of the organic surface increases, ⇐ S approaches values characteristic of low surface energy polymers. It was possible to correlate the variation of ⇐ a P and ⇐ a D with the nature of the surface, i.e. organic/mineral, hydrated/dry. At complete coverage of the mineral, the surface properties measured are the organic coating ones.