Open AccessReduced Interfacial Entanglement Density Affects the Boundary Conditions of Polymer Flow
Author(s) -
Oliver Bäumchen,
Renate Fetzer,
Karin Jacobs
Publication year - 2009
Publication title -
physical review letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.688
H-Index - 673
eISSN - 1079-7114
pISSN - 0031-9007
DOI - 10.1103/physrevlett.103.247801
Subject(s) - slippage , quantum entanglement , materials science , viscoelasticity , slip (aerodynamics) , polymer , boundary value problem , boundary (topology) , flow (mathematics) , mechanics , chemical physics , condensed matter physics , thermodynamics , physics , composite material , quantum mechanics , mathematical analysis , mathematics , quantum
Hydrodynamic boundary conditions play a crucial role in the flow dynamics of thin films and can be probed by the analysis of liquid front profiles. For long-chained polymer films it was reported that a deviation from a symmetric profile is a result of viscoelastic effects. In this Letter, however, evidence is given that merely a slip-boundary condition at the solid-liquid interface can lead to an asymmetric profile. Variation of molecular weight shows that slippage is directly linked to chain entanglements. We find a reduced entanglement density at the solid-liquid interface (factors 3 to 4), which stresses the importance of considering nonbulk polymer properties in the vicinity of an interface