Spreading of solids on liquids

Dussan EBV (1979) On the spreading of liquids on solid surfaces static and dynamic contact lines. Ann Rev Fluid Mech 11 371 00... 

These surfactants can lower the surface tension of water, y, to values below 20 mN m-1 (most surfactants lower y to values in the region of 30 mN ur1) and hence they are sometimes described as superwetters. They are very useful for enhancing the wetting and spreading of liquids on solid substrates. 

Zisman, W. A., Relation of Chemical Constitution to the Wetting and Spreading of Liquids on Solids, NRL Rept. 4932 (May 15, 1957) Decade of Basic and Applied Science in the Navy, Office of Naval Research, Rept. ONR-2, 30 (1957). 

In addition to incorporating a cationic material into the composition, deposition of unmodified silicones onto hair may be influenced by varying the viscosity of the silicone polymer or the particle size of the emulsion droplet (102-110). Quantitatively, the spreading of liquids on solid surfaces was discussed by Dodge, and is given by the following equation, which demonstrates the dependence of spreading rate on the droplet volmne and viscosity ... 

In Chapter 3 entitled Dry spreading of liquids on solids (originally the last lecture) the general phenomenon of surface wetting by liquids with different spreading coefficients is examined in its most basic aspects. The specific case of polymer melts is also taken into consideration here we are confronted with many new possibilities either an anomalous slippage of the melt at the wall surface or in some other cases an anomalous sticking of the chains to the wall. 

A. Marmur, Equilibrium and spreading of liquids on solid surfaces, Adv. Colloid Interface Sci. 19, 75... 

The study of surface tension is really a branch of surface chemistry, and its development has been exceedingly rapid in the last decade. Thus, adhesion can be considered to be partially an exercise in wetting and spreading of liquids on solid surfaces. The flotation of ores is accomplished by gravity differences as well as by the adhesion of the solid particle to an air bubble, and it involves solid-liquid-gas interfaces. It is possible to reduce the vaporization of water from bodies of water with large surfaces such as reservoirs and lakes, by adding a monolayer of a substance such as hexadecanol or other surface-active agents. The action of soaps produces a decrease in surface tension on water. Many other applications in our modem environment can be readily identified. 

Leger, L., Spreading of liquids on solid surfaces, in Physicochemical Hydrodynamics Interfacial Phenomena, Velarde, M. G. (Ed.), Plenum Press, New York, 1988, pp. 721-740. 

The spreading of liquids on solid surfaces or into porous media is of primary importance in fields as different as soil science, oil recovery,... 

Example 15.2. Spreading of liquids on solids using the Fowkes equation (With data from Fowkes, 1964). The table below provides dispersion values of the surface tensions of several solids obtained from spreading pressure measurements of diverse adsorbates (therefore the range of reported values). 

The limitation means that the question of adsorption at interfaces will not be considered. However, some situations, such as the spreading of liquids on solids, are considered, where liquid-vapour, solid-vapour and solid-liquid interfaces are all present. 

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