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Abstract Cellular solids composed of a network of interconnected pores offer low‐density and high strength‐to‐weight ratio as exemplified by wood, bones, corks, and shells. However, the slender edges and low connectivity of the structs in cellular lattices make them vulnerable to buckle, fracture, or collapse. Here, by taking advantage of the continuity of a thin film that can follow curvatures and dissipate energy, shellular materials are created by dip coating a wireframe of the primitive triply periodic minimal surface (TPMS) with an aqueous solution of lyotropic liquid crystalline graphene oxide (GO)/polymer composites. Regulated by surface tension, GO nanosheets align on the polymer soap film as the stress builds up during drying. When the wireframe mesh density is low, the shellular material is film‐dominated, demonstrating superior mechanical strength (384.30 Nm kg⁻¹) and high specific energy absorption (1.59 kJ kg⁻¹) yet lightweight (equivalent density, 0.063 g cm⁻³), with an energy absorption rate comparable to that of carbon nanotube‐based lattices but a lower equivalent density. The study offers insights into designing lightweight yet high‐strength structural materials that also function as impact energy absorbers. 

A ubiquitous structural feature in biological systems is texture in extracellular matrix that gains functions when hardened, for example, cell walls, insect scales, and diatom tests. Here, we develop patterned liquid crystal elastomer (LCE) particles by recapitulating the biophysical patterning mechanism that forms pollen grain surfaces. In pollen grains, a phase separation of extracellular material into a pattern of condensed and fluid-like phases induces undulations in the underlying elastic cell membrane to form patterns on the cell surface. In this work, LCE particles with variable surface patterns were created through a phase separation of liquid crystal oligomers (LCOs) droplet coupled to homeotropic anchoring at the droplet interface, analogously to the pollen grain wall formation. Specifically, nematically ordered polydisperse LCOs and isotropic organic solvent (dichloromethane) phase-separate at the surface of oil-in-water droplets, while, different LCO chain lengths segregate to different surface curvatures simultaneously. This phase separation, which creates a distortion in the director field, is in competition with homeotropic anchoring induced by sodium dodecyl sulfate (SDS). By tuning the polymer chemistry of the system, we are able to influence this separation process and tune the types of surface patterns in these pollen-like microparticles. Our study reveals that the energetically favorable biological mechanism can be leveraged to offer simple yet versatile approaches to synthesize microparticles for mechanosensing, tissue engineering, drug delivery, energy storage, and displays. 

Abstract Direct ink writing of liquid crystal elastomers (LCEs) offers a new opportunity to program geometries for a wide variety of shape transformation modes toward applications such as soft robotics. So far, most 3D‐printed LCEs are thermally actuated. Herein, a 3D‐printable photoresponsive gold nanorod (AuNR)/LCE composite ink is developed, allowing for photothermal actuation of the 3D‐printed structures with AuNR as low as 0.1 wt.%. It is shown that the printed filament has a superior photothermal response with 27% actuation strain upon irradiation to near‐infrared (NIR) light (808 nm) at 1.4 W cm⁻²(corresponding to 160 °C) under optimal printing conditions. The 3D‐printed composite structures can be globally or locally actuated into different shapes by controlling the area exposed to the NIR laser. Taking advantage of the customized structures enabled by 3D printing and the ability to control locally exposed light, a light‐responsive soft robot is demonstrated that can climb on a ratchet surface with a maximum speed of 0.284 mm s⁻¹(on a flat surface) and 0.216 mm s⁻¹(on a 30° titled surface), respectively, corresponding to 0.428 and 0.324 body length per min, respectively, with a large body mass (0.23 g) and thickness (1 mm). 

Abstract Liquid crystal elastomers (LCEs) are of interest for applications such as soft robotics and shape‐morphing devices. Among the different actuation mechanisms, light offers advantages such as spatial and local control of actuation via the photothermal effect. However, the unwanted aggregation of the light‐absorbing nanoparticles in the LCE matrix will limit the photothermal response speed, actuation performance, and repeatability. Herein, a near‐infrared‐responsive LCE composite consisting of up to 0.20 wt% poly(ethylene glycol)‐modified gold nanorods (AuNRs) without apparent aggregation is demonstrated. The high Young's modulus, 20.3 MPa, and excellent photothermal performance render repeated and fast actuation of the films (actuation within 5 s and recovery in 2 s) when exposed to 800 nm light at an average output power of ≈1.0 W cm⁻², while maintaining a large actuation strain (56%). Further, it is shown that the same sheet of AuNR/LCE film (100 µm thick) can be morphed into different shapes simply by varying the motifs of the photomasks.