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Deorientation effects on extrusion rheometry of a thermotropic copolyester

✍ Scribed by Marta Tormes; María Eugenia Muñoz; Anton Santamaría

Book ID
102491219
Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
435 KB
Volume
18
Category
Article
ISSN
1022-1336

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✦ Synopsis

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 capillary and the slit can explain these non‐linearities. Assuming that the order parameter, S, relaxes exponentially with time, the Doi‐Edwards model for the shear flow of rod‐like polymers is used to adjust experimental data.

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