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Korean Journal of Chemical Engineering

, Volume 17, Issue 4, pp 444–448 | Cite as

Microscopic spreading of nonreactive perfluoropolyalkylether film on amorphous carbon surfaces

  • Min Chan Kim
  • Myung S. Jhon
Article
  • 28 Downloads

Abstract

A spreading mechanism of nonfunctional perfluoropolyalkylehter (PFPE) on carbon surfaces is proposed. For the thin thin-film regime, adsorption-desorption is a main driving force for spreading, and the surface diffusion coefficients increase as the film thickness increases. A two-dimensional virial equation is employed to explain the dependency of surface diffusion coefficient on the film thickness. For the thick thin-film regime, the spreading characteristic is determined by the disjoining pressure gradient. We adopt a slip boundary condition to analyze the thick thin-film regime. This modification of the boundary condition reasonably explains the dependence of surface diffusion coefficients on film thickness.

Key words

Microscopic Spreading Surface Diffusion PFPE Partial Slip Effect 

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Copyright information

© Korean Institute of Chemical Engineering 2000

Authors and Affiliations

  1. 1.Department of Chemical EngineeringCheju National UniversityChejuKorea
  2. 2.Department of Chemical EngineeringCarnegie Mellon UniversityPittsburghUSA

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