DEORIENTATION EFFECTS ON EXTRUSION RHEOMETRY OF A THERMOTROPIC COPOLYESTER

Authors
TORMES M MUNOZ ME SANTAMARIA A
Citation
M. Tormes et al., DEORIENTATION EFFECTS ON EXTRUSION RHEOMETRY OF A THERMOTROPIC COPOLYESTER, Macromolecular rapid communications, 18(7), 1997, pp. 591-599
Citations number
25
Categorie Soggetti
Polymer Sciences
Journal title
Macromolecular rapid communications → ACNP
ISSN journal
10221336
Volume
18
Issue
7
Year of publication
1997
Pages
591 - 599
Database
ISI
SICI code
1022-1336(1997)18:7<591:DEOERO>2.0.ZU;2-2
Abstract
Extrusion rheometry experiments with a commercial thermotropic liquid crystalline copolyester show concave Bagley plots and convex pressure profiles. A loss of the orientation produced at the entrance of the ca pillary and the slit can explain these non-linearities. Assuming that the order parameter, S, relaxes exponentially with time, the Doi-Edwar ds model for the shear flow of rod-like polymers is used to adjust exp erimental data.