Jingqing Li, Lei Wang, Donghong Yu, Jesper de Claville Christiansen, Shichun Jiang
Wall Slip of Polyolefin Plastomers under Oscillatory Shear
Appl. Rheol. 28:3 (2018) 33226 (14 pages)Abstract: The oscillatory shear rheological behaviors of a polyolefin plastomer (POP) at various temperatures were examined within its linear viscoelastic (LVE) regime. The apparent storage modulus, loss modulus, complex modulus, complex viscosity, and phase angle of POP at various temperatures are all found gap dependent, revealing that wall slip occurred under the applied oscillatory shear with the shear stress amplitude controlled constant. All Han plots and van Gurp-Palmen (vGP) plots of POP samples overlapped each other at various gaps at a certain temperature, suggesting that a time-gap-superposition (TGS) is valid with all the apparent angular frequency dependent storage modulus and loss modulus of POP at various gaps shifted to their master curves at a selected reference gap. This indicates that the wall slip can be understood as adding a dashpot in series to POP sample only with the apparent relaxation time multiplied by a shift factor. By TGS, a method to determine the wall slip length b and the actual oscillatory shear rheology of the fluids was consequently established. The results showed that the obtained b is dependent on temperature and wall slip made it possible to extend the experimental angular frequency range to lower frequencies. Further analysis revealed that wall slip did not influence the Arrhenius viscosity dependence of POP on temperature, while the viscous flow activation energy decreased. © 2018 Applied Rheology.
DOI 10.3933/ApplRheol-28-33226
-- full text PDF
available for subscribers --
-- open access PDF extractavailable for non-subscribers --
You have no password-free access to Applied Rheology Online. If you are a subscriber, enter login details below. For password-free access, we need your IP address. Sample manuscripts for free download can be found here ►
Forgotten your login details? Send an email with subject "AR login" to login@appliedrheology.org
Purchase this article for 20 € ? ►
Appl Rheol 28 (2018) issues:
© Applied Rheology 2018