Wetting Behaviour of Liquids towards Teflon

Experimental investigation of the effect of a liquid's surface tension and polarity on the wetting behaviour towards non-polar solids assumes that the effect of polarity can also be characterised by adequate interfacial energy values. Such a method is the determination of the wetting tension on non-polar solids. Wetting tensions measured under the conditions of advancing contact angles by means of the Wilhelmy-method confirm this assumption. On the other hand, hysteresis investigations on Teflon showed that the poarity of liquids and not the different roughness of solid surfaces is the most important reason for the formation of different contact angles at the same liquid surface tension.