Cluster prevalence in concentrated ring-chain mixtures under shear.

Area of Science:

• Polymer science
• Materials science
• Rheology

Background:

• Semiflexible ring polymers form clusters and stacks in concentrated solutions.
• Weak shear flow can reorient these polymer stacks, especially in more concentrated systems.

Purpose of the Study:

• Investigate the effect of mixing linear chains and semiflexible, rod-like chains on polymer clustering under shear.
• Determine the correlation between monomer fraction and clustering behavior in polymer mixtures.

Main Methods:

• Studying polymer solutions containing mixtures of linear chains and ring polymers.
• Applying weak shear to observe the reorientation of polymer structures.
• Analyzing the impact of varying monomer fractions on clustering dynamics.

Main Results:

• Increased linear chain fraction decreases effective density and reduces clustering.
• Low concentrations of linear chains can maintain equilibrium clustering.
• Shear flow disrupts clustering in mixtures, while equilibrium clustering is preserved at low chain concentrations.

Conclusions:

• Mixing linear chains and rings offers a method to control polymer clustering.
• Low linear chain concentrations can preserve or enhance equilibrium clustering.
• This approach allows for the creation of organized polymer structures that are sensitive to weak shear reorientation.