Electric field-controlled on-demand surface deformation in liquid crystal polymer networks with topological defects

Reconfigurable surface morphing control of liquid crystalline polymer (LCP) films at micro or nano scales has emerged as a promising strategy for various applications. Creating reproducible and adjustable platforms enhances their versatility. This study presents a method for controlling stimuli-responsive deformations in liquid crystal polymer network (LCN) films by forming defect arrays using a three-dimensional (3D) electric field generated by crossed electrode systems. The director field of the system can be simulated, enabling investigation of high-temperature deformations through activation force density calculations. To explain the laterally asymmetric deformation of our film, a 3D analysis of the activation force density vector field was essential. Topographical modifications at room temperature are also achieved by incorporating dichroic dye to the monomeric mixture, which promote local monomer diffusion during photopolymerisation. Additionally, by varying the configurations of signal and ground electrodes, different defect structures are generated, leading to distinct deformation patterns at elevated temperatures. Our findings demonstrate that LCN films in this study exhibit programmable nanometre-scale shape deformations, allowing for varied surface patterns from a single setup. This platform significantly enhances the potential of nano- or micro-morphing LCP coatings for advanced applications across multiple fields.