Solvent-Assisted 4D Programming and Reprogramming of Liquid Crystalline Organogels

Adv Mater. 2022 Feb;34(5):e2107855. doi: 10.1002/adma.202107855. Epub 2021 Dec 13.

Abstract

Encoding molecular ordering during liquid crystalline network (LCN) formation endows preprogrammed but fixed shape morphing in response to external stimuli. The incorporation of dynamic covalent bonds enables shape reprogramming but also permanently alters the network structures. Here, an entropic approach that can program complex shapes via directed solvent evaporation from an isotropic LCN organogel is discoursed. Different shapes can be erased and reprogrammed from the same LCN on demand depending on the modes of deformation of the organogel during solvent evaporation. The ability to decouple network synthesis and molecular alignment relaxes the requirements to LCN chemistry and alignment methods, allowing for the realization of a variety of origami/kirigami structures and 4D shape morphing of LCNs printed from the digital light processing technique with unattainable spatial and temporal controls.

Keywords: alignment programming; directed solvent evaporation; liquid crystalline network; shape morphing.