MEASUREMENTS OF HYDROPHOBIC AND ADHESION FORCES ON STAINLESS-STEEL SURFACES IN WATER

An atomic force microscope (AFM) has been used to measure the long-ran ge hydrophobic attraction forces and the adhesion forces between the s tainless steel surface and a methylated silica sphere immersed in wate r. The adhesion forces on both contaminated hydrophobic and cleaned hy drophilic surfaces have been correlated with the interfacial energies obtained by contact angle measurements. Both long-range attractive and adhesive force are stronger for the non-cleaned surface possibly due to the ''hydrophobic effect''. This hydrophobic interaction becomes ne utralized with the presence of hydrophilic groups (i.e; potassium salt ) on the surface.