Ion-Binding Phenomena of Polyelectrolytes

of Synthetic Chemistry, Nagoya University, Chikusa-Ku, Nagoya, Japan 

The force acting between fixed charges on polyion and counter-ions is not unique but varies with combination of counter-ion and fixed group. Therefore, the cause for counter-ion binding may depend on the ionic species. 

Eric S legny (ed.). Poly electrolytes, 57-77. All Rights Reserved. Copyright 1974 by D. Reidel Publishing Company, Dordrecht-Holland. 

However, this kind of the effective charge is generally inapplicable to the calculation of thermodynamic properties of linear polyelectrolyte solutions. For example, the calculated results depend on molecular weight of the polyelectrolyte, whereas most observed values are independent of molecular weight. 

Thermodynamic properties of polyelectrolyte solutions are mostly determined by ionic distribution around the polyion skeleton. To explain thermodynamic properties, therefore, the rod-like model may be effective. It is assumed that the polyion is a rod of infinite length and has smeared charges distributed uniformly over the surfaces of the rod. That is, a real polyion chain consists of a series of discrete charges and each charge is surrounded by its own ionic atmosphere. If the radius of ionic atmosphere is 

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The setting of AB cements is an example of gelation, and gelation is related to ion binding. A theoretical examination of the various phenomena associated with ion binding and gelation finds its clearest exposition in the field of polyelectrolytes. Moreover, this field may be wider than it seems at first. 

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