Heat capacities of diphenyl, p-terphenyl and p-quaterphenyl from 180 K to their melting points

Authors:

• Jan Wąsicki,
• Magdalena Radomska,
• R. Radomski

Abstract

The heat capacities of diphenyl, p-terphenyl and p-quaterphenyl from 180 K to their melting points were measured with a Perkin-Elmer DSC 1B scanning calorimeter. Anomalies were observed in the heat capacity curves for p-terphenyl (from 400 K to the melting point) and p-quaterphenyl (from 190 to 260 K, and from 450 to 540 K). It is assumed that the anomalies near the melting points of the compounds under consideration could be related both to modification of the motion of the phenyl rings (external or/and internal) and to change in the motion of the molecules as a whole (diffusion phase). © 1982 Wiley Heyden Ltd., Chichester and Akadémiai Kiadó, Budapest.