Effect of melt viscosity on the crystallization kinetics of pre-sheared metallocene polyethylene melts
authors Krakowiak, J; Martins, JA; Zhang, WD
nationality International
journal COLLOID AND POLYMER SCIENCE
author keywords Melt memory; Crystallization; Saturation; Metallocene
keywords POLYMER MELTS; ISOTACTIC POLYPROPYLENE; ISOTHERMAL CRYSTALLIZATION; MEMORY; ENTANGLEMENTS; DISENTANGLEMENT; DYNAMICS; BEHAVIOR; FLOW
abstract This work aims to verify the impossibility mentioned in the literature of saturating the crystallization kinetics of pre-sheared metallocene polyethylene melts. Similarly to results reported for other materials, and contrary to other published works, an acceleration of crystallization kinetics with the increase of shear strain and its saturation at large strain values was found. Similar strain values, with the same temperature variation, were evaluated with independent experiments using different devices, which allowed us to identify the steady state as the melt state responsible for the saturation of crystallization kinetics. Since this is a partially disentangled melt state, with viscosity lower than that of fully entangled (relaxed) melts, we assign the acceleration of crystallization kinetics by application of shear, and its saturation, mainly to the facilitated diffusion of chain segments to the lamellae growth front. This conclusion is supported additionally with the experimental results of other authors.
publisher SPRINGER
issn 0303-402X
year published 2011
volume 289
issue 12
beginning page 1347
ending page 1359
digital object identifier (doi) 10.1007/s00396-011-2451-7
web of science category Chemistry, Physical; Polymer Science
subject category Chemistry; Polymer Science
unique article identifier WOS:000292974700005
  ciceco authors
  impact metrics
journal analysis (jcr 2019):
journal impact factor 1.536
5 year journal impact factor 1.612
category normalized journal impact factor percentile 24.793
dimensions (citation analysis):
altmetrics (social interaction):



 


Apoio

1suponsers_list_ciceco.jpg