A systematic study of the isothermal crystallization of the mono-alcohol n-butanol monitored by dielectric spectroscopy

摘要

Isothermal crystallization of the mono-hydroxyl alcohol n-butanol was studied with dielectric spectroscopy in real time. The crystallization was carried out using two different sample cells at 15 temperatures between 120 K and 134 K. Crystallization is characterized by a decrease of the dielectric intensity. In addition, a shift in relaxation times to shorter times was observed during the crystallization process for all studied temperatures. The two different sample environments induced quite different crystallization behaviors, consistent and reproducible over all studied temperatures. An explanation for the difference was proposed on the background of an Avrami analysis and a Maxwell-Wagner analysis. Both types of analysis suggest that the morphology of the crystal growth changes from a higher dimension to a lower at a point during the crystallization. More generally, we conclude that a microscopic interpretation of crystallization measurements requires multiple probes, sample cells, and protocols. (C) 2015 AIP Publishing LLC.