Application of Thermodynamics to the Chemistry of Rubber

Abstract

Abstract The purpose of this paper is to show how thermodynamic data on rubber and related substances can be employed in studying and predicting their reactions. The method will be illustrated by the results of recent studies on rubber and iso-prene made at the National Bureau of Standards. These results enable us to predict the conditions which favor the polymerization of isoprene to form rubber, and also the conditions which favor the reverse reaction, the thermal decomposition of rubber to give isoprene. Rossini, in his review paper on “Modern Thermodynamics,” makes the following statement : “The ultimate end of chemical thermodynamics may be said to be the evaluation of the free energy of formation, from the appropriate fundamental units of matter, of every substance in all possible states….” Our chief object, then, for rubber is to obtain as accurately as possible the free energies of formation of rubber, sulfur, rubber-sulfur compounds and other forms of vulcanized rubber, isoprene and all other substances with which rubber reacts or from which it may be made.