ISSN:
0887-6266
Keywords:
temperature-modulated calorimetry
;
TMC
;
temperature-modulated differential scanning calorimetry
;
TMDSC
;
melting
;
crystallization
;
molecular nucleation
;
poly(oxyethylene)
;
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Temperature-modulated calorimetry, TMC, is used to evaluate the temperature region of metastability between crystallization and melting. While crystals like indium can be made to melt practically reversibly during a TMC cycle of low amplitude so that sufficient crystal nuclei remain unmelted, linear macromolecules cannot, because of their need to undergo molecular nucleation. Modulation amplitudes varying from ±0.2 to ±3.0 K are used to assess the temperature gap between the slow crystallization region and the melting of metastable crystals of poly(oxyethylene) (PEO) of molar mass 1500 Da. This low molar mass PEO serves as a model compound with a metastable gap of melting/crystallization that can be bridged by TMC with a large modulation amplitude. © 1997 John Wiley & Sons, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America. J Polym Sci B: Polym Phys 35: 1877-1886, 1997
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
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