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Abstract Miniature shape‐morphing soft actuators driven by external stimuli and fluidic pressure hold great promise in morphing matter and small‐scale soft robotics. However, it remains challenging to achieve both rich shape morphing and shape locking in a fast and controlled way due to the limitations of actuation reversibility and fabrication. Here, fully 3D‐printed, sub‐millimeter thin‐plate‐like miniature soft hydraulic actuators with shape memory effect (SME) for programable fast shape morphing and shape locking, are reported. It combines commercial high‐resolution multi‐material 3D printing of stiff shape memory polymers (SMPs) and soft elastomers and direct printing of microfluidic channels and 2D/3D channel networks embedded in elastomers in a single print run. Leveraging spatial patterning of hybrid compositions and expansion heterogeneity of microfluidic channel networks for versatile hydraulically actuated shape morphing, including circular, wavy, helical, saddle, and warping shapes with various curvatures, are demonstrated. The morphed shapes can be temporarily locked and recover to their original planar forms repeatedly by activating SME of the SMPs. Utilizing the fast shape morphing and locking in the miniature actuators, their potential applications in non‐invasive manipulation of small‐scale objects and fragile living organisms, multimodal entanglement grasping, and energy‐saving manipulators, are demonstrated.
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Light‐Driven Shape‐Memory Porous Films with Precisely Controlled Dimensions
Abstract Shape‐memory polymers (SMPs) are an intriguing class of smart materials possessing reversible shape change and recovery capabilities. Effective routes to shape‐memory porous films (SMPFs) are few and limited in scope owing to the difficulty in manipulating the shape change of pores by conventional methods. Herein we report an unconventional strategy for crafting light‐driven SMPFs by judiciously constructing highly ordered porous films via a facile “breath figure” approach, followed by sequential vapor crosslinking and nondestructive directional light manipulation. Micropores can thus be transformed into other shapes including rectangle, rhombus and size‐reduced micropores at room temperature. The transformed micropores can be reverted to their original shapes by either thermal annealing or UV irradiation. As such, this strategy expands the rich diversity of SMPs accessible.
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- Award ID(s):
- 1727313
- PAR ID:
- 10050381
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 8
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 2139-2143
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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