Periodic Reporting for period 1 - MULTIMODAL (Multimodal Sensory-Motorized Material Systems)
Reporting period: 2023-01-01 to 2025-06-30
The paradigm shift described above is actively explored using various materials concepts. MULTIMODAL addresses this challenge using shape-changing liquid crystal networks (LCNs) that undergo controlled, untethered motions in response to different stimuli. Inspired by biological sensory-motor functions, we will develop materials capable of perceiving multiple environmental cues and responding to them through controlled motor functions – shape change or locomotion. These materials will be “trained” to strengthen upon repeated activation, “heal” when damaged, and mechanically adapt to different environments. They will be utilized in designing soft robots with autonomous and interactive functions.
Technological disruptions often stem from advancements in materials development and fabrication technologies. Paradigm shifts on how materials are perceived can profoundly impact society, well-being, and our understanding of the world. Materials that “learn from life”, embodying functions akin to intelligence of living systems, such as those developed in the MULTIMODAL project, will play an important role in this transformation.
Our studies have resulted in 17 published scientific articles, many in the most prestigious journals in our field (Science, Nature Materials, Advanced Materials, Angewandte Chemie International Edition). We are on a good track - some research areas, such as dynamic and supramolecular liquid-crystal elastomers and robotic constructs, are progressing as planned, while others, like dynamic hydrogels and processes driven by sensitized isomerization, have been unplanned and opened new avenues, as is expected in curiosity-driven research.
1. Halogen Bonding in Dynamic Liquid Crystal Elastomers (Angewandte Chemie International Edition, 2023). This promising approach allows materials to respond to moderate energy inputs, such as heat from a human palm, and introduces self-healing properties. Looking ahead, we believe functionalization with halogen bonding to lead to liquid crystal elastomers without covalent crosslinking, an important step towards recyclability and reprocessing.
2. Multiresponsive and Multifunctional Actuators. We developed photochemical actuators that respond to light and magnetic fields (ACS Applied Materials & Interfaces, 2025), and light and humidity (Journal of Materials Chemistry B, 2024). We also designed systems that integrate shape memory programming with reversible actuation (Advanced Functional Materials, 2024) by combining permanent covalent and dynamic supramolecular crosslinks. Future work will extend these design principles to cholesteric liquid crystal elastomers to create materials with dynamic color-changing properties.
3. Light-Driven Toroidal Structures for Microscale Swimming (Nature Materials, 2024). Movement in viscous environments poses a significant challenge for microscopic organisms, as highlighted by Purcell’s Scallop Theorem. We introduced a solution to this challenge, toroidal LCN structure that leverage zero-elastic-energy-modes (ZEEMs) to achieve autonomous locomotion in various environments. These ZEEM-driven LCNs can move toward or away from light, whether on solid surfaces or in liquid media. Most notably, powered by continuous optical input, they exhibit untethered swimming in the Stokes regime, navigating with remarkable agility in three dimensions at a Reynolds number as low as 0.0001.
4. Photoswitching via Sensitized Isomerization (Science, 2023). One of the major challenges in photoswitchable compounds is the reliance on UV light to control molecular and material properties. In a collaboration led by Prof. Rafal Klajn, we developed an indirect sensitized isomerization method that eliminates this limitation, enabling efficient photoswitching with any visible, or even near-infrared, light. We recently integrated this approach, termed Disequilibration by Sensitization under Confinement (DESC), into polymers (unpublished), aiming to use low-energy light to precisely control their structure and functionality.