Steering with light: indexable photomotility in liquid crystalline polymers

作者:Babaei Mahnoush; Clement J Arul; Dayal Kaushik; Shankar M Ravi*
来源:RSC Advances, 2017, 7(83): 52510-52516.
DOI:10.1039/c7ra10619j

摘要

Harnessing light to achieve manipulation and motility in meso and mm-scale systems offers the ability to remotely trigger actuation without requiring on-board power. Central to achieving macroscopic photomotility is the generation of asymmetric interaction between the light-responsive actuator and a substrate. Here, we demonstrate a facile route for achieving indexable, stepped translation of structures fabricated from azobenzene-functionalize liquid crystalline polymers (ALCP). The symmetry breaking in the dynamics of coiling (during irradiation) and uncoiling (when the light is turned off) as a function of the director orientation in splayed ALCP strips leads to asymmetric reaction forces in the interaction with a surface. The broken symmetry leads to directional translation of the center of mass in discrete steps for each on/off cycle of irradiation. Creating composite structures offers a route for hard-coding the trajectories of motility across a range of trajectories that are either rectilinear or curvilinear. Expanding this approach can offer a framework for achieving steerable light-powered microrobots that can translate on arbitrary surface topographies.

  • 出版日期2017