Journal
RHEOLOGICA ACTA
Volume 50, Issue 9-10, Pages 753-766Publisher
SPRINGER
DOI: 10.1007/s00397-011-0554-1
Keywords
Shear banding; Rolie-Poly model; Velocity band; Molecular orientational band; Molecular diffusion and relaxation
Categories
Funding
- Ministry of Education, Culture, Sports, Science and Technology [18068009]
- G-COE
- Grants-in-Aid for Scientific Research [23350113, 21350063] Funding Source: KAKEN
Ask authors/readers for more resources
Shear-banding phenomenon in the entangled polymer systems was investigated in a planar Couette cell with the diffusive Rolie-Poly (ROuse LInear Entangled POLYmers) model, a single-mode constitutive model derived from a tube-based molecular theory. The steady-state shear stress sigma (s) was constant in the shear gradient direction while the local shear rate changed abruptly, i.e., split into the bands. We focused on the molecular conformation (also calculated from the Rolie-Poly model) around the band boundary. A band was found also for the conformation, but its boundary was much broader than that for the shear rate. Correspondingly, the first normal stress difference (N (1)) gradually changed in this diffuse boundary of the conformational bands (this change of N (1) was compensated by a change of the local pressure). For both shear rate and conformation, the boundary widths were quite insensitive to the macroscopic shear rate but changed with various parameters such as the diffusion constant and the relaxation times (the reptation and the Rouse times). The broadness of the conformational banding, associated by the gradual change of N (1), was attributed to competition between the molecular diffusion (in the shear gradient direction) and the conformational relaxation under a constraint of constant sigma (s).
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available