Special applications of thermal analysis in the investigation of liquid/solid systems

The thermal analysis method was successfully applied to study of the heterogeneity properties of solid surfaces and adsorbed liquid films. The method utilized the thermogravimetric mass loss Q-TG and differential Q-DTG curves with respect to temperature and time obtained during thermodesorption process of liquids from solid surfaces under quasi-isothermal conditions. On the basis of the experimental data, using an analyzer equipped with an automatic ultra-slow heating device and a labyrinthine conical crucible, the discontinuous properties of adsorbed layers, changes in the mechanism of the wetting process due to the liquid/surface interactions, adsorption capacity of the tested samples and nature of surface-active sites have been presented. It appears that the special thermogravimetry technique is very useful in studying the liquid/solid systems and competes well with the traditional ones because of the speed and accuracy of the obtained data and the simplicity of experimental operations.