Notes on The Polymer-Mixed Solvents System. I The refinement of the free energy expression

Publisher Website
Google Scholar
Abstract
The free energy expression derived by Scott for the polymer-mixed solvents system are refined and amplified, removing the assumptions which are not always applicable to the actual cases, although it was introduced by him for the sake of simplicity. Owing to scantiness of the available data and to difficulties of exact, calculation, the phase diagrams of the system using the results obtained are not given here. Determination of plait points and the problems in the osmotic pressure measurement in mixed solvents will be discuss d elsewhere. Here, we confined ourselves to formulate the free energy expression for various systems also involving the systems in which one or two of the constituents are associated liquids as a special case where the assumption (b) is far from true. Application of the result obtained to some problems-in viscosity, osmotic pressure, and swelling phenomena will be presented in the following-articles. This paper was presented at the Annual Meeting of the Tokyo Institute of Technology, where the treatment of associated liquids was discussed with particular reference to the applicability of the above methods to the thermodynamic problems of association. In the writer’s opinion, the generality of the thermodynamic function derived here in the application to equilibria involving transformation between various “polymeric” species of the associated liquid may be accessible when the volume effect of the associated liquid on the entropy term in these systems must be encountered. Obviously the Flory-Tobolsk y-Bratz treatment is applicable only to the linear “polymer” such as alcohol, and we may go too far to say that our treatment is also-applicable to the three dimentional “polymer”-Our treatment is supposed, however, to be not far from true even in such a case, since the entropy of mixing in the above systems containing associated liquids as one or two components was formulated on the assumption that the submolecules of the “polymer” are distributed at random, i. e., this corresponds to the Bragg-Williams approximation.

This publication has 11 references indexed in Scilit: