Transient effects of drying creep in nanoporous solids: understanding the effects of nanoscale energy barriers.

ABSTRACT: The Pickett effect is the phenomenon of creep enhancement during transient drying. It has been observed for many nanoporous solids, including concrete, wood and Kevlar. While the existing micromechanical models can partially explain this effect, they have yet to consider nanoscale dynamic effects of water in nanopores, which are believed to be of paramount importance. Here, we examine how creep deformations in a slit pore are accelerated by the motion of water due to drying forces using coarse-grained molecular dynamics simulations. We find that the drying that drives water flow in the nanopores lowers both the activation energy of pore walls sliding past one another and the apparent viscosity of confined water molecules. This lowering can be captured with an analytical Arrhenius relations

SUBMITTER: Sinko R 

PROVIDER: S-EPMC4971260 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature