CORRELATION OF LINE TENSION AND SOLID-LIQUID INTERFACIAL-TENSION FROMTHE MEASUREMENT OF DROP SIZE DEPENDENCE OF CONTACT ANGLES

Drop-size-dependent contact angle measurements were performed on mica surfaces coated with a fluoro compound (FC 721) and the following five liquids: decane, dodecane, methyl salicylate, ethylene glycol, and gl ycerol. The line tensions obtained from these measurements are in the range 1-5 mu J/m. In an attempt to link line tension values to the sur face properties of solids and liquids, these line tensions, together w ith those obtained previously, were plotted over the solid-liquid inte rfacial tension gamma(sl). The result is a reasonably smooth monotonic curve. This result was discussed in terms of the phase rule for capil lary systems. (C) 1995 Academic Press, Inc.