SOLID-SOLID TRANSITION AND SOLUBILITY OF EVEN N-ALKANES

Solubility data for long-chain n-alkanes in shorter-chain alkanes have been used to predict the melting temperatures of the polymorphic phase stable at lower temperatures. In the case of alkanes having no polymorphic phases (hexadecane and octadecane) the predicted melting temperatures are consistent with the conventional melting temperature of the pure alkanes. The predicted melting temperatures of alkanes possessing polymorphic phases are consistent with the transition temperatures of pure alkanes (tetracosane, hexacosane, octacosane, dotriacontane and hexatriacontane). The transition between the polymorphic phases of pure even n-alkanes proceeds by the transitional liquid state at the melting temperatures of the solid phases stable at lower temperatures.