SURFACE AND STRUCTURAL FORCES MEASURED BETWEEN SILICA SURFACES IN 1,2-ETHANEDIOL

Scanning probe microscopy is used to measure the forces between silica surfaces in 1,2-ethanediol (ethylene glycol). The force profile shows a small double layer repulsion at larger separations, and a short ran ge, repulsive hydration-like force close to contact. The length scale of the short range force measured is compared to other measurements of surface forces in similar systems in the literature. By comparisons w ith these other measurements, we propose this force is due to solvatio n, and conclude that hydrogen bonding does not present a significant i nfluence upon the magnitude of this force. (C) 1997 Elsevier Science B .V.