dc.contributor.author |
Toda A. |
|
dc.contributor.author |
Androsch R. |
|
dc.contributor.author |
Schick C. |
|
dc.date.accessioned |
2022-02-09T20:31:35Z |
|
dc.date.available |
2022-02-09T20:31:35Z |
|
dc.date.issued |
2021 |
|
dc.identifier.issn |
0024-9297 |
|
dc.identifier.uri |
https://dspace.kpfu.ru/xmlui/handle/net/168756 |
|
dc.description.abstract |
Quantitative analyses of the melting kinetics of superheated polymer crystals, including the isothermal analysis of the time dependence of melting and nonisothermal analysis of the heating-rate dependence of melting, were carried out by fast scanning calorimetry on linear polyethylene that has a narrow melting temperature region. The time evolution of the decrease in the total crystallinity during melting was modeled using a first-order kinetic equation with a rate coefficient, which defines a characteristic melting time under isothermal conditions. A superheating-dependent rate coefficient characterizes the heating-rate dependence of the nonisothermal melting. The obtained results of both analyses consistently suggest the presence of a superheating-dependent melting kinetics unique to initially metastable long-chain polymer crystals with the melting rate nonlinearly dependent on superheating. The dependence is exponential at least in a certain range of superheating. Examinations of the dependence on crystallization temperature, which controls the thickness of lamellar crystals, suggest an activated process of detaching a whole crystalline stem. A possible mechanism of the activation barrier is discussed in connection with distinct types of chain folding. |
|
dc.relation.ispartofseries |
Macromolecules |
|
dc.title |
Melting Kinetics of Superheated Polymer Crystals Examined by Isothermal and Nonisothermal Fast Scanning Calorimetry |
|
dc.type |
Article |
|
dc.relation.ispartofseries-issue |
18 |
|
dc.relation.ispartofseries-volume |
54 |
|
dc.collection |
Публикации сотрудников КФУ |
|
dc.relation.startpage |
8770 |
|
dc.source.id |
SCOPUS00249297-2021-54-18-SID85115652473 |
|