Xin Peng,Tianqi Liu,Qin Zhang,Cong Shang,Qing-Wen Bai,Huiliang Wang
Convenient patterning and precisely programmable shape deformations are crucial for the practical applications of shape deformable hydrogels. Here, a facile and versatile computer-assisted ion inkjet printing technique is described that enables the direct printing of batched, very complicated patterns, especially those with well-defined, programmable variation in cross-linking densities, on one or both surfaces of a large-sized hydrogel sample. A mechanically strong hydrogel containing poly(sodium acrylate) is first prepared, and then digital patterns are printed onto the hydrogel surfaces by using a commercial inkjet printer and an aqueous ferric solution. The complexation between the polyelectrolyte and ferric ions increases the cross-linking density of the printed regions, and hence the gel sample can undergo shape deformation upon swelling/deswelling. The deformation rates and degrees of the hydrogels can be conveniently adjusted by changing the printing times or the different/gradient grayscale distribution of designed patterns. By printing appropriate patterns on one or both surfaces of the hydrogel sheets, many complex 3D shapes are obtained from shape deformations upon swelling/deswelling, such as cylindrical shell and forsythia flower (patterns on one surface), ding (patterns on both surfaces), blooming flower (different/gradient grayscale distributive patterns on one surface), and non-Euclidean plates (different/gradient grayscale distributive patterns on both surfaces).
Jingyi Zhang,Yu Wang,Yuxi Sun,Shuaishuai Sun,Zhenbang Xu,Jun Li,Ji Li,Xinglong Gong
The soft actuators capable of responding to multiple stimuli and adapting to changing environments have attracted growing interest in the flexible multifunctional materials. However, how to achieve high degree of freedom (DoF), precise control, and complex shape transformation of the multi-stimuli responsive soft actuator, still remains challenging. Here, we report a multi-responsive soft actuator with various controllable sophisticated deformations by integrating a magnetically sensitive elastomer (MSE) with a liquid crystal elastomer (LCE). Through regulating the stimuli strength and the geometrical dimensions and material parameters of elastomers, the bending angle and curling curvature of the actuator are accurately controlled ranging from 0 to 58.9° and from 0.23 to 1.29 cm–1, respectively. The facile material-structural synergistic design drives the complex 3D shape deformations (e.g., bidirectional bending, shrinkage/bending, rolling/bending, and twisting/bending) of the actuator. More importantly, due to its photosensitive characteristics, the shape-morphing of the actuator can be manipulated locally and sequentially, which markedly enriches the DoFs. The flower-shaped actuator displays multiple deformation modes, and the hand-shaped actuator transforms between 8 gestures under the control of laser and magnetic field, proving that the multi-responsive soft actuators have great application potentials in future bioengineering, soft manipulators, and flexible electronics.
危险品化学品经营许可证（带存储）