Electrohydrodynamics in nanochannels coated by mixed polymer brushes: Effects of electric field strength and solvent quality

Qianqian Cao, Xiu Tian, Hao You

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We examine the electrohydrodynamics in mixed polymer brush-coated nanochannels and the conformational dynamics of grafted polymers using molecular dynamics simulations. Charged (A) and neutral polymers (B) are alternately grafted on the channel surfaces. The effects of the electric field strength and solvent quality are addressed in detail. The dependence of electroosmotic flow characteristics and polymer conformational behavior on the solvent quality is influenced due to the change of the electric field strength. The enhanced electric field induces a collapse of the neutral polymer chains which adopt a highly extended conformation along the flow direction. However, the thickness of the charged polymer layer is affected weakly by the electric field, and even a slight swelling is identified for the A-B attraction case, implying the conformational coupling between two polymer species. Furthermore, the charged polymer chains incline entirely towards the electric field direction oppositely to the flow direction. More importantly, unlike the neutral polymer chains, the shape factor of the charged polymer chains, which is used to describe the overall shape of polymer chains, is reduced significantly with increasing the electric field strength, corresponding to a more coiled structure.

Original languageEnglish (US)
Article number035003
JournalModelling and Simulation in Materials Science and Engineering
Volume26
Issue number3
DOIs
StatePublished - Feb 2 2018

Fingerprint

Electrohydrodynamics
electrohydrodynamics
brushes
electric field strength
Brushes
Electric Field
Polymers
Electric fields
polymers
electric fields
Polymer Dynamics
Electroosmotic Flow
Swelling
flow characteristics
Conformation
Molecular Dynamics Simulation
swelling
attraction
Conformations
Molecular dynamics

Keywords

  • electrohydrodynamics
  • molecular dynamics
  • nanochannels
  • polymer brush

ASJC Scopus subject areas

  • Modeling and Simulation
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Computer Science Applications

Cite this

Electrohydrodynamics in nanochannels coated by mixed polymer brushes : Effects of electric field strength and solvent quality. / Cao, Qianqian; Tian, Xiu; You, Hao.

In: Modelling and Simulation in Materials Science and Engineering, Vol. 26, No. 3, 035003, 02.02.2018.

Research output: Contribution to journalArticle

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