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Abstract Liquid crystal elastomer (LCE) is a type of soft active material that generates large and reversible spontaneous deformations upon temperature changes, facilitating various environmentally responsive smart applications. Despite their success, most existing LCE metamaterials are designed in a forward fashion based on intuition and feature regular material patterns, which may hinder the reach of LCE’s full potential in producing complex and desired functionalities. Here, we develop a computational inverse design framework for discovering diverse sophisticated temperature-activated and -interactive nonlinear behaviors for LCE metamaterials in a fully controllable fashion. We generate intelligent LCE metamaterials with a wide range of switchable functionalities upon temperature changes. By sensing the environment, these metamaterials can realize maximized spontaneous area expansion/contraction, precisely programmable enclosed opening size change, and temperature-switchable nonlinear stress–strain relations and deformation modes. The optimized unit cells feature irregular LCE patterns and form complex and highly nonlinear mechanisms. The inverse design computational framework, optimized material patterns, and revealed underlying mechanisms fundamentally advance the design capacity of LCE metamaterials, benefiting environment-aware and -adaptive smart materials.
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This content will become publicly available on September 1, 2027
Porous liquid crystal elastomers for thermal-driven tunable acoustic properties
Achieving tunable acoustic properties is crucial for adaptive sound regulation in dynamically changing environments across engineering and biomedical applications. However, conventional porous materials possess fixed pore structures that result in static acoustic responses, while existing active systems often rely on complex, bulky, and multi-component assemblies that limit practical integration. Here, we present a porous liquid crystal elastomer (LCE) as a structurally simple yet highly reconfigurable material platform enabling wide-range acoustic tuning. By exploiting reversible, thermal-driven reconfiguration of its pore structure, the porous LCE achieves full-range modulation of sound absorption, transitioning from near-zero to near-perfect absorption at target frequencies, while enabling frequency-selective tuning through on-demand shifts of absorption peaks. Experiments combined with numerical modeling reveal that this tunability originates from temperature-controlled changes in effective porosity and pore size, which can be systematically programmed during fabrication. Importantly, the acoustic performance is highly reversible and repeatable over multiple heating and cooling cycles, ensuring robust and reliable operation. This work establishes porous LCEs as a promising material platform for active acoustic wave manipulation, with various potential applications, including adaptive noise control, acoustic imaging, and wireless communication.
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- Award ID(s):
- 2318188
- PAR ID:
- 10712995
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Materials Today
- Volume:
- 98
- Issue:
- C
- ISSN:
- 1369-7021
- Page Range / eLocation ID:
- 103394
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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