Self-sustained entropy-driven flow in nano-confined polymer melts

Abstract

We present a Monte Carlo simulation study of the Brownian motion of polymer chains in a melt confined in a periodically asymmetric channel of nanometric dimensions. We assume no friction between the chains and the channel. A detailed analysis of the conformations of the chains reveals the presence of a favorable entropy gradient along the easy flow direction. For high molecular weight chains, this gradient is seen to drive a self-sustained polymer flow with Peclet numbers as high as 0.9, which makes our observation experimentally accessible. Much weaker efficiences are observed at low molecular weights. We show that the unexpected directed Brownian motion of polymers in confined geometries is of significant importance in the design and stabilization of platelet nanocomposites which typically age over time under quiescent conditions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 869–875