Journal of Thermal Analysis and Calorimetry

, Volume 110, Issue 3, pp 1353–1365

Quality of Brazilian vegetable oils evaluated by (modulated) differential scanning calorimetry

Authors

    • Institute for Forest UtilizationAlbert-Ludwigs-University Freiburg
  • Gustaaf Schoukens
    • Department of TextilesGhent University
  • Leo Vonck
    • Topchim N.V
  • Dirk Stanssens
    • Topchim N.V
  • Henk Van den Abbeele
    • Topchim N.V
Article

DOI: 10.1007/s10973-011-2132-2

Cite this article as:
Samyn, P., Schoukens, G., Vonck, L. et al. J Therm Anal Calorim (2012) 110: 1353. doi:10.1007/s10973-011-2132-2

Abstract

Vegetable oils are increasingly replacing fossil-oil-based polymers, and therefore aimed at being used in polymerization reactions from −20 to 100 °C. Therefore, phase transitions and heat capacities in this temperature range should be well characterized to optimize processing conditions and energy inputs. By using the DSC analysis, only small primary correspondence or divergence between different oil types are seen as a function of their degree of unsaturation, but it does not clearly distinguish detailed features such as shoulder bands related to the separate melting processes of single fatty acid components. By using modulated DSC analysis, the combined analysis of reversing and non-reversing heat signals provides better results. The latter confirms that the melting is not a physical one-step process, but equilibrates between phase transitions and enthalpic reorganizations of the fatty acids that can be monitored separately. The specific heat capacities measured during modulated DSC are somewhat lower than traditional calorimetric measurements, but relate to the degree of unsaturation. The thermal behavior of palm-, soy-, sunflower-, corn-, castor-, and rapeseed-oil is discussed in relation to their composition, by applying a first or second heating scan.

Keywords

Thermal analysis Heat Flow Heat capacity Modulated DSC Vegetable oil

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011