Induced folding model in the melt crystallization kinetics of nucleated high-density polyethylene

Citation
G. Di Marco et M. Pieruccini, Induced folding model in the melt crystallization kinetics of nucleated high-density polyethylene, NUOV CIM D, 20(12BIS), 1998, pp. 2479-2484
Citations number
4
Categorie Soggetti
Physics
Journal title
NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS
ISSN journal
03926737 → ACNP
Volume
20
Issue
12BIS
Year of publication
1998
Pages
2479 - 2484
Database
ISI
SICI code
0392-6737(199812)20:12BIS<2479:IFMITM>2.0.ZU;2-U
Abstract
Melting and isothermal crystallization kinetics of nucleated high-density p olyethylene are observed by means of a conventional differential scanning c alorimeter. The temperature dependence of the isothermal crystallization ra te is analysed in terms of a model expression for the secondary nucleation free enthalpy which is derived under the assumption that the close vicinity of a nucleant molecule to a basal plane drastically reduces the local valu e of the folding free energy (induced folding). The linear dimensions of th e region where the latter happens to be depleted appear to be determined by those of a nucleant molecule. In large nuclei, the possibility that all st em pairs undergo induced folding by the same nucleant molecule has to be ex cluded. Both the basal and lateral specific surface free energies can be wo rked out from a fitting procedure, and are in good agreement with the liter ature data.