Title: Driving Liquid Crystal Polymer Films to “dance” in Electric Fields.
When: Friday, June 07, (2019), 12:00.
Place: Sala de Seminarios, Module 03, Faculty of Sciences, Universidad Autónoma de Madrid.
Speaker: Nicholas B. Tito, Theory of Polymers & Soft Matter Group Department of Applied Physics Eindhoven University of Technology, The Netherlands.
Liquid crystal polymer networks (LCNs) exhibit remarkable fluctuations in shape and size when doped with a stimulus-responsive chemical species. For example LCNs containing azobenzene mesogens, which undergo trans-cis isomerization when exposed to light, display exotic curling and folding behavior at the macroscale upon illumination. These physical changes are brought about by fluctuations in mesogen order at the molecular scale when exposed to the stimulus. Because molecular order is pre-programmed into the material during synthesis, these microscopic changes drive a concerted macroscopic response.
In this talk, molecular dynamics simulation is employed to examine how LCNs can be shape-shifted by electric stimuli.1 Comparison will be made to recent experiments that use electric fields to achieve localised shape fluctuations in LCN films having dipolar mesogens, leading to the possibility of coatings with "fingerprint-like" haptic feedback or self-cleaning surfaces.
1. Liu, D.; Tito, N. B.; Broer, D. J. Nat. Comm. 8, 1879 (2017).