Phase transitions of 1,2-cyclohexanediol isomers studied by polarised light microscopy and differential thermal analysis

Polarised light microscopy and DTA have been used to study the phase transi tions observed in cis and trans-1,2-cyclohexanediol during heating/cooling cycles performed between ambient and melting temperatures to prove that the presence of impurities even in trace amounts can affect the thermal proper ties of the substances. Good quality commercial material before and after f urther purification were used in this study. (C) 2001 Elsevier Science B.V. All rights reserved.