ISSN:
1572-8943
Keywords:
β-cyclodextrin
;
ethyl benzoate
;
inclusion complex
;
kinetics
;
thermal decomposition
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The stability of β-cyclodextrin·ethyl benzoate·6H2O(β-CD·C6H5COOC2H5·6H2O) was investigated by TG and DSC. The mass loss takes place in three stages: the dehydration occurs at 50-120°C; the dissociation of β-CD·C6H5COOC2H5occurs at 200-260°C; the decomposition of β-CD begins at 280°C. The kinetics of the dissociation of β-CD·C6H5COOC2H5in a dry nitrogen flow was studied by means of thermogravimetry both at constant temperature and linearly increasing temperature. The results show that the dissociation of β-CD·C6H5COOC2H5is dominated by a three-dimensional diffusion process (D3). The activation energy E is 116.19 kJ mol-1and the pre-exponential factor A 6.5358·109min-1. Cyclodextrin is able to form inclusion complexes with a great variety of guest molecules, and the studies focus on the energy of binding between cyclodextrin and the guest molecule. In this paper, the β-cyclodextrin·ethyl benzoate inclusion complex was studied by fluorescence spectrophotometry and infrared absorption spectroscopy, and the results show that the stable energy of inclusion complexes of β-CD with weakly polar guest molecules consists mainly of van der Waals interaction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1010129028436
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