The Structure of the Collodion Membrane and Its Electrical Behavior v. the Influence of the Thickness of Dried Collodion Membranes upon Their Electromotive Behavior by Karl Sollner and Charles W. Carr

The electrochemical properties of collodion membranes are known to vary greatly with the nature of the collodion preparation used, more acid preparations yielding membranes of higher electrochemical activity, x-s The assumption has always been made, tacitly or expressly, that the thickness of the membrane is of no influence. Thus, it has been generally assumed that the characteristic concentration potential e across dried collodion membranes must be independent of the thickness of the membranesY We became doubtful of the validity of this assumption. As was pointed out in a preceding communication, 5 the concentration potentials across different membrane specimens frequently vary considerably, even if the membranes are prepared from the same collodion solution under conditions as nearly iden' deal as possible. The following set of facts also needs to be considered. I t has been demonstrated that the behavior of dried collodion membranes with solutions of strong electrolytes is due to (1) its micellar structural arrangement, that is, to the presence of interstices of larger than minimal (molecular) di-