ABSTRACT

Solid surface tension is an important thermodynamic quantity governing many technological processes. However, because of the absence of surface mobility, a solid phase is very different from a liquid phase; hence, one cannot measure the surface tension of a solid phase directly as is the case for a liquid phase. For example, the process of particle adhesion to a substrate can be modeled by the net free energy change, AFadh, of the system during the adhesion process, which depends explicitly on the solid (particle) surface tensions: the net free energy change per unit surface area for the adhesion process of a square particle is given by

AFadh = ypv - ypl - ysl (1)

the chemistry of the solid in an unknown manner and hence affect the values of ysi and/or ysv. Therefore, it is also important to ensure that the solid surfaces are as inert as possible in order to minimize such effects, by appropriate choice of the liquid.