Skip to main content
Journal cover image

Nonlinear Shear Rheology of Entangled Polymer Rings

Publication ,  Journal Article
Parisi, D; Costanzo, S; Jeong, Y; Ahn, J; Chang, T; Vlassopoulos, D; Halverson, JD; Kremer, K; Ge, T; Rubinstein, M; Grest, GS; Srinin, W ...
Published in: Macromolecules
March 23, 2021

Steady-state shear viscosity (γ˙) of unconcatenated ring polymer melts as a function of the shear rate γ˙ is studied by a combination of experiments, simulations, and theory. Experiments using polystyrenes with Z ≈ 5 and Z ≈ 11 entanglements indicate weaker shear thinning for rings compared to linear polymers exhibiting power law scaling of shear viscosity ∼γ˙-0.56 ± 0.02, independent of chain length, for Weissenberg numbers up to about 102. Nonequilibrium molecular dynamics simulations using the bead-spring model reveal a similar behavior with ∼γ˙-0.57 ± 0.08 for 4 ≤ Z ≤ 57. Viscosity decreases with chain length for high γ˙. In our experiments, we see the onset of this regime, and in simulations, which we extended to Wi ∼104, the nonuniversality is fully developed. In addition to a naive scaling theory yielding for the universal regime ∼γ˙-0.57, we developed a novel shear slit model explaining many details of observed conformations and dynamics as well as the chain length-dependent behavior of viscosity at large γ˙. The signature feature of the model is the presence of two distinct length scales: the size of tension blobs and much larger thickness of a shear slit in which rings are self-consistently confined in the velocity gradient direction and which is dictated by the size of a chain section with relaxation time 1/γ˙. These two length scales control the two normal stress differences. In this model, the chain length-dependent onset of nonuniversal behavior is set by tension blobs becoming as small as about one Kuhn segment. This model explains the approximate applicability of the Cox-Merz rule for ring polymers.

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Macromolecules

DOI

EISSN

1520-5835

ISSN

0024-9297

Publication Date

March 23, 2021

Volume

54

Issue

6

Start / End Page

2811 / 2827

Related Subject Headings

  • Polymers
  • 40 Engineering
  • 34 Chemical sciences
  • 09 Engineering
  • 03 Chemical Sciences
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Parisi, D., Costanzo, S., Jeong, Y., Ahn, J., Chang, T., Vlassopoulos, D., … Grosberg, A. Y. (2021). Nonlinear Shear Rheology of Entangled Polymer Rings. Macromolecules, 54(6), 2811–2827. https://doi.org/10.1021/acs.macromol.0c02839
Parisi, D., S. Costanzo, Y. Jeong, J. Ahn, T. Chang, D. Vlassopoulos, J. D. Halverson, et al. “Nonlinear Shear Rheology of Entangled Polymer Rings.” Macromolecules 54, no. 6 (March 23, 2021): 2811–27. https://doi.org/10.1021/acs.macromol.0c02839.
Parisi D, Costanzo S, Jeong Y, Ahn J, Chang T, Vlassopoulos D, et al. Nonlinear Shear Rheology of Entangled Polymer Rings. Macromolecules. 2021 Mar 23;54(6):2811–27.
Parisi, D., et al. “Nonlinear Shear Rheology of Entangled Polymer Rings.” Macromolecules, vol. 54, no. 6, Mar. 2021, pp. 2811–27. Scopus, doi:10.1021/acs.macromol.0c02839.
Parisi D, Costanzo S, Jeong Y, Ahn J, Chang T, Vlassopoulos D, Halverson JD, Kremer K, Ge T, Rubinstein M, Grest GS, Srinin W, Grosberg AY. Nonlinear Shear Rheology of Entangled Polymer Rings. Macromolecules. 2021 Mar 23;54(6):2811–2827.
Journal cover image

Published In

Macromolecules

DOI

EISSN

1520-5835

ISSN

0024-9297

Publication Date

March 23, 2021

Volume

54

Issue

6

Start / End Page

2811 / 2827

Related Subject Headings

  • Polymers
  • 40 Engineering
  • 34 Chemical sciences
  • 09 Engineering
  • 03 Chemical Sciences