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Abstract Shape‐morphing magnetic soft materials, composed of magnetic particles in a soft polymer matrix, can transform shape reversibly, remotely, and rapidly, finding diverse applications in actuators, soft robotics, and biomedical devices. To achieve on‐demand and sophisticated shape morphing, the manufacture of structures with complex geometry and magnetization distribution is highly desired. Here, a magnetic dynamic polymer (MDP) composite composed of hard‐magnetic microparticles in a dynamic polymer network with thermally responsive reversible linkages, which permits functionalities including targeted welding for magnetic‐assisted assembly, magnetization reprogramming, and permanent structural reconfiguration, is reported. These functions not only provide highly desirable structural and material programmability and reprogrammability but also enable the manufacturing of functional soft architected materials such as 3D kirigami with complex magnetization distribution. The welding of magnetic‐assisted modular assembly can be further combined with magnetization reprogramming and permanent reshaping capabilities for programmable and reconfigurable architectures and morphing structures. The reported MDP are anticipated to provide a new paradigm for the design and manufacture of future multifunctional assemblies and reconfigurable morphing architectures and devices.
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Light-Directed Organization of Polymer Materials from Photoreactive Formulations
This perspective presents a recently developed approach to organize polymer and polymer composite materials through a new form of light-directed organization of photoreactive polymeric media. Under suitable conditions, such media will interact with light, in a mutual dynamic process, that results in the spontaneous organization of both the input light field and, importantly, the polymer media. New material structures can be created in free-radical-initiated media, polymer blends and polymer–solvent mixtures, as well as possibly more complex, multicomponent formulations. An overview of the underlying principles and chemical phenomena and exemplary material structures are presented. Materials produced using this new processing approach can be used as functional coatings, textured surfaces, and membranes, as well as a host of other applications via selection of polymer composition. Key open questions and areas for further inquiry and advancement are presented. Coupling the dynamics of light pattern formation processes to photoreactive matter is a promising new approach to the organization of materials for a range of critical applications and reveals interesting nonlinear dynamic phenomena in the organization of materials.
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- Award ID(s):
- 1751621
- PAR ID:
- 10251673
- Date Published:
- Journal Name:
- Chemistry of materials
- Volume:
- 32
- Issue:
- 7
- ISSN:
- 1520-5002
- Page Range / eLocation ID:
- 2673
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.chemmater.9b05373
