Separation and Electrical Effects

For metals and semiconductors, the mechanism of charging is well understood in terms of electron transfer across the surfaces in contact. However, for polymers, the charging mechanism is less well appreciated, although empirical lists of polymers can be drawn up as in Fig. 8.29. 

The results of such contact experiments are highly dependent on the presence of moisture and on the addition of ionic salts to the polymers. Especially interesting are those studies with polymers blended with ionomers. In a model of 

In conclusion, there are many mechanisms which can alter the level of molecular adhesion between solid bodies. Some of these may be elastic and reversible while others are time dependent, leading to drag and hysteresis. Thus, adhesion measurements cannot generally be explained in terms of a simple adhesion energy or range. The mechanisms of adhesion can magnify or reduce the adhesion force by several orders of magnitude. 

Newton, I., Opticks, Smith and Walford, London, 1704 (reprinted Dover, New York, 1952, p 396). 

Bowden, F.P. and Tabor, D., Friction and iMbrication cf Solids, Clarendon Press, Oxford, Part II, 

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