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An X-Ray Diffraction Study of Triglyceride Polymorphism

Published online by Cambridge University Press:  06 March 2019

H. M. Zacharis ,
D. Mitcham ,
N. Lovegren  and
M. Gray
H. M. Zacharis
Affiliation:
Southern Regional Research Center P. O. Box 19687, New Orleans, Louisiana 70179
D. Mitcham
Affiliation:
Southern Regional Research Center P. O. Box 19687, New Orleans, Louisiana 70179
N. Lovegren
Affiliation:
Southern Regional Research Center P. O. Box 19687, New Orleans, Louisiana 70179
M. Gray
Affiliation:
Southern Regional Research Center P. O. Box 19687, New Orleans, Louisiana 70179
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Abstract

The polymorphism of an homologous series of highly purified mixed triglycerides has been studied using powder and single crystal X-ray diffraction techniques, in conjunction with thermal analysis and infrared spectroscopy. From thermal analysis, three polymorphs were identified. Single crystals of the most stable polymorph were obtained for two members of the series, 2-acetodimyristin (14-2-14) and 2-acetodipalmitin (16-2-16). Their unit-cell and sub-cell dimensions were used to interpret the powder data, and to provide preliminary general information about the crystal packing for this polymorph. Of the two other polymorphs identified, the first one (obtained by rapid cooling of the melt) is disordered, and transforms on standing, to a second, unstable intermediate polymorph. Infrared spectroscopy showed that for at least two of the three polymorphs, the long chain acyl groups of the triglycerides are in a parallel packing arrangement.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 18: Twenty-Third Annual Conference on Applications of X-ray Analysis, August 7-9, 1974 , 1974 , pp. 535 - 544
Copyright
Copyright © International Centre for Diffraction Data 1974

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References

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