INVESTIGADORES
PASTORINO Claudio
artículos
Título:
Frictional forces between strongly compressed, non-entangled polymer brushes: Molecular dynamics simulations and scaling theory
Autor/es:
A. GALUSCHKO; L. SPIRIN; T. KREER; A. JOHNER; CLAUDIO PASTORINO; J. WITTMER; J. BASCHNAGEL
Revista:
LANGMUIR
Editorial:
AMER CHEMICAL SOC
Referencias:
Año: 2010 vol. 26 p. 6418 - 6429
ISSN:
0743-7463
Resumen:
By means of molecular dynamics simulations and scaling theory we study the response of opposing polymer brushesto constant shear motion under good solvent conditions. Model systems that contain explicit solvent molecules(Lennard-Jones dimers) are compared to solvent-free systems while varying of the distance between the grafted layersand their molecular parameters, chain length and grafting density. Our study reveals a power-law dependence ofmacroscopic transport properties on the Weissenberg number,W, beyond linear response. For instance, we find that thekinetic friction constant scales as μ∼W^0.57 for large values of W.We develop a scaling theory that describes our data andprevious numerical data including recent experiments.