Electroosmotic Flow in Mixed Polymer Brush-Grafted Nanochannels

Area of Science:

• Nanofluidics
• Polymer Science
• Computational Chemistry

Background:

• Mixed polymer brush-grafted nanochannels are advanced nanostructured hybrid materials.
• Understanding their behavior is crucial for applications in separation, filtration, and sensing.

Purpose of the Study:

• To investigate the electrokinetic transport dynamics and polymer brush conformations in mixed polymer brush-grafted nanochannels.
• To elucidate the effects of solvent quality and grafting density on fluid flow and brush structure.

Main Methods:

• Coarse-grained molecular dynamics simulations were employed.
• Simulations focused on electrokinetic transport and polymer conformational analysis.

Main Results:

• The polymer brush forms vertically-layered and longitudinally-separated structures due to the interplay of electroosmotic flow (EOF) and electric fields.
• Solvent quality impacts brush conformation and EOF transport properties.
• EOF flux shows a non-monotonic dependence on grafting density, while EOF velocity in the channel's center region shows a monotonic dependence.

Conclusions:

• The study reveals complex structure formation and transport phenomena in mixed polymer brush nanochannels.
• Results highlight the tunability of nanochannel transport properties through polymer architecture and solvent environment.