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Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
Structure of a semidilute polymer solution under steady shear
Prasanth P Jose1, Grzegorz Szamel
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
The Journal of Chemical Physics
|September 25, 2007
Summary
Shear flow alters polymer solution structure, modifying intra- and interchain correlations. This leads to anisotropic patterns and influences nonlinear shear viscosity, primarily due to intrachain effects.
Area of Science:
- Polymer Physics
- Soft Matter Science
- Computational Materials Science
Background:
- Semidilute polymer solutions exhibit complex structures due to intra- and interchain correlations.
- Equilibrium solutions show near-complete cancellation of these correlations in their structure factor.
- Understanding polymer behavior under flow is crucial for materials science and engineering.
Purpose of the Study:
- To investigate the structural changes in semidilute polymer solutions under steady shear flow.
- To analyze the contributions of intra- and interchain correlations to the structure factor and pair correlation function.
- To examine the origin of nonlinear shear viscosity in sheared polymer solutions.
Main Methods:
- Brownian dynamics computer simulations were employed.
- The study focused on steady, uniform shear flow conditions.
- Analysis included the structure factor and pair correlation function.
Main Results:
- Shear flow modifies intra- and interchain correlation contributions, leading to incomplete cancellation.
- Anisotropic patterns in the structure factor were observed, consistent with experimental findings.
- For small wave vectors, the interchain contribution dominates the structure factor change.
- Intrachain contributions are dominant for the short-distance distortion of the pair correlation function and nonlinear shear viscosity.
Conclusions:
- Shear flow breaks the symmetry of polymer solutions, altering correlation patterns.
- Both intra- and interchain correlations play distinct roles in the response to shear.
- Intrachain effects are significant for nonlinear viscosity and local structural distortions.
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