Thermodynamics Research Center / ThermoML | Thermochimica Acta

ABSTRACT

Homologous series of crystallisable C8-C22even-numbered alkane oligomers with either maleate or itaconate monoesters end-groups were synthesized. Their total phase change enthalpy (DHtpce) and entropy (DStpce) on melting, determined by DSC, show a linear dependence with the number of carbons of the alkyl chain. A comparison was performed with corresponding succinate derivatives. The influence of the end functions on Stpcewas examined in view of Stpcevalues estimated by the group additivity approach. A fair agreement between the experimental and the estimated entropy values could be demonstrated. Thermogravimetric analysis (TGA) has shown that the maleate oligomers are less stable than the corresponding succinate and itaconate derivatives. This behaviour could be confirmed by the activation energies of the degradation process.