REFERENCE MATERIALS FOR ENERGY AND TEMPERATURE CALIBRATIONS OF DTA AND DSC INSTRUMENTATION IN THE RANGE 100-300 K

Fourteen organic compounds, 1-pentene, 2-methylbutane, 2-methyl-1,3-bu tadiene (isoprene), n-pentane, 2-chloropropane, ethyl alcohol, 2,2,4-t rimethylpentane, n-hexane, n-heptane, 1,3-difluorobenzene, 1,2-dichlor oethane, hexafluorobenzene, cyclohexane and diphenyl ether, as new ref erence materials for energy and temperature calibrations of differenti al thermal analysers (DTA) and differential scanning calorimeters (DSC ) in the temperature range 100-300 K, were investigated. The purities, triple point and transition temperatures, fusion and transition entha lpies of these compounds were measured using a low-temperature DTA app aratus developed by the CTM of the CNRS in Marseille. The results obta ined were compared with those produced by adiabatic precision calorime try. Our data are in good agreement with literature values. Enthalpies of fusion and transition, triple point and transition temperatures ar e reproduced within +/-1% and +/-0.1 K, respectively.