Mintaek Oh, SeokāIn Lim, Junhwa Jang, Youngjae Wi Ā· 10 authors
Abstract To develop smart ionic skins capable of multiāresponsiveness and switchable ionic conductivity, a stimuliāresponsive and ionic conductive azobenzeneābased monomer is newly synthesized, uniaxially oriented, and polymerized for anisotropic liquid crystal elastomers (LCEs). Since the uniaxially oriented monodomain LCE with ionic asymmetric azobenzene monomers (iāAAM) is prepared by thermal oligomerization, uniaxial stretching, and subsequent photopolymerization, the stimuliāresponsive iāAAM LCE is thermally contracted by increasing the temperature above T NI as well as is bent along the aligned direction by irradiating it with UV light. In addition to the change of shape, the ionic conductivity of the LCE is reversible in response to heat and light stimuli. Polydomain iāAAM LCE polymerized without the stretching process exhibits higher ionic conductivity than stretched monodomain LCE due to the initially formed stable ionic pathways. Ionic conductivity can also be switched simultaneously by polarity changes in response to the photoisomerization of iāAAM, increased mobility from heat, and an elastic mechanoresponse from external stresses. These iāAAM LCEābased soft grippers exhibit stimuliāresponsive grasping and releasing actuation and detect ionic conductivity switches finely, suggesting potential as smart skins for advanced soft robots.