A. Nagarajan, S. Mukherjee, et al.
Journal of Applied Mechanics, Transactions ASME
Amorphous siloxane polymers are the backbone of high-voltage insulation materials. The natural hydrophobicity of their surface is a necessary property for avoiding leakage currents and dielectric breakdown. As these surfaces are exposed to the environment, electrical discharges or strong mechanical impact can temporarily destroy their water-repellent properties. After such events, however, a self-healing process sets in and restores the original hydrophobicity within some hours. In the present study, we investigate possible mechanisms of this restoration process. Using large-scale, all-atom molecular dynamics simulations, we show that molecules on the material surface have augmented motion that allows them to rearrange with a net polarization. The overall surface region has a net orientation that contributes to hydrophobicity, and charged groups that are placed at the surface migrate inward, away from the vacuum interface and into the bulk-like region. Our simulations provide insight into the mechanisms for hydrophobic self-recovery that repair material strength and functionality and suggest material compositions for future high-voltage insulators. © 2011 American Chemical Society.
A. Nagarajan, S. Mukherjee, et al.
Journal of Applied Mechanics, Transactions ASME
Kafai Lai, Alan E. Rosenbluth, et al.
SPIE Advanced Lithography 2007
I. Morgenstern, K.A. Müller, et al.
Physica B: Physics of Condensed Matter
Fernando Marianno, Wang Zhou, et al.
INFORMS 2021