Nanoscale engineering of responsive surfaces for contamination resistance

G. Yiapanis, L. Shaw, K. Ley, D. Henry, S. Maclaughlin, E. Evans, I. Yarovsky
RMIT University, AU

Keywords: responsive surfaces, adhesion, wettability, molecular dynamics

Summary:

We present a theoretical approach for quantitative prediction of adhesion within a three-component system using all-atom classical Molecular Dynamic simulations. We apply this approach to predict the dirt-shielding qualities of responsive polymer brushes grafted on organic and inorganic substrates. The surface models are designed to mimic the responsive stay-clean behavior of the Lady’s Mantle leaf1. Using calculations of the contact-angle of nano-sized water droplets on soft deformable surfaces and previously developed in-silico adhesive force measurements2, we investigate the adhesion of the carbon based contaminants3 to adaptive surfaces in dry and aqueous environments. Our results show that polyethylene glycol brushes impart dirt-shielding qualities provided that the substrate is sufficiently hydrophilic and robust. Similar to the flexible hairs of the Lady’s Mantle leaf, the grafted chains contribute to a repulsive energy barrier that prevents adhesion of contaminants to the hydrated surface. Our new approach can be applied to test wettability and adhesion of essentially any material.