Isothermal crystallization: Thermal and optical study of PEG

Citation
R. Berlanga et al., Isothermal crystallization: Thermal and optical study of PEG, J MACR S PH, B40(3-4), 2001, pp. 327-334
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS
ISSN journal
0022-2348 → ACNP
Volume
B40
Issue
3-4
Year of publication
2001
Pages
327 - 334
Database
ISI
SICI code
0022-2348(2001)B40:3-4<327:ICTAOS>2.0.ZU;2-8
Abstract
In this work, the solidification process and the crystal growth kinetics of Polyethylene glycol 4000 (PEG4000) and polyethylene glycol 6000 (PEG6000) (molecular average weight 4000 and 6000, respectively) were characterized b y thermal optical microscopy (OM) and differential scanning calorimetry (DS C). The growth rate decreased with increasing crystallization temperature. The kinetic rate constant was lower for PEG6000 than for PEG4000 (29,300 an d 32,900 K-2, respectively). This behavior is related to the different numb er of folds (folding index n) of the crystal structures. From comparison of microscopy and calorimetry measurements, the kinetic rate constant values were higher by microscopy due to different melt histories, self-nucleation, and degree of entanglement.