Phase Transition and Glass Transitions in Isocyanocyclohexane Studied by a Polaro-Calorimeter.

Abstract

Calorimetric and electric measurements have been performed simultaneously on Isocyanocyclohexane by using a polaro-calorimeter, which is essentially an adiabatic calorimeter with built-in electrodes in the sample cell. A phase transition between plastically crystalline and ordered low-temperature crystalline phases was found at 192.6 K. The corresponding enthalpy and entropy changes were determined to be 6.177 kJ mol-1 and 32.07 J K-imoM, respectively. Glassy crystal was formed by supercooling the plastically crystalline state. It underwent three glass transitions at 55 K, 130 K and 160 K.