Unlike earlier materials that primarily aimed at regaining their original form, this self-healing electronic device focuses on enabling customised shape changes.
Researchers at Ajou University and other South Korean institutes have developed a new design for crumple-recoverable electronics, drawing inspiration from the natural unfolding mechanism of butterfly wings. The composite material’s hardness can be controlled without additional substances. This material mimics the butterfly wing’s ability to transition from a wet, crumpled state to a dry, unfolded state.
The electronics are based on a combination of silver nanowires, a shape memory polymer (SMP), and an elastomer. The nanowires conduct electricity and assist in changing the phase of the SMP through Joule heating, allowing the material to transform and become rigid as needed.
The mechanical properties of these sheet-like devices can be transformed through thermal modulation. This process enables the material to transition from an elastic state (with a stiffness of 2 MPa), which is suitable for smoothing out wrinkles formed during crumpling, to a plastic state (with a stiffness of 1,315 MPa) appropriate for free-standing operation.
When the electronic device is crumpled, the SMP allows it to fold without permanent damage. Applying heat via silver nanowires transforms the material, helping the electronics to unfold back to their original flat shape without wrinkles or damage.
The researchers demonstrated the practical application of this technology by creating touch panels measuring 7 cm by 7 cm. These panels can be crumpled and packed into small capsules with a volume of 1 ml.
Post-unpacking, these touch panels can be used as a flat and smooth surface, retaining their touch-sensing capabilities.Unlike traditional foldable devices that can deteriorate over time at folding points, these crumple-recoverable electronics can withstand repeated crumpling and unfolding without losing functionality.
This technology not only advances the creation of robots that can change shape, wearable electronics that adapt to different forms, and compressible displays, but it also paves the way for innovative self-healing materials in medical and engineering applications.
The distinct feature of this self-healing electronic device, compared to previous materials, is its focus on enabling customised shape changes. Unlike earlier materials that primarily aimed at regaining their original form, these new devices maintain their functionality and adaptability even after undergoing transformation.
This technology could revolutionise the way we think about electronics in wearables, foldable devices, and other areas where flexibility and resilience are crucial. The ability to pack electronics into small volumes without compromising their functionality opens up new possibilities for deploying technology in various fields, including healthcare, consumer electronics, and space exploration.