Auxiliary soft beam for the amplification of the elasto-capillary coiling: Towards stretchable electronics

Area of Science:

• Materials Science
• Mechanical Engineering
• Soft Robotics

Background:

• Traditional functional materials for information transfer (electronic/photonic) are stiff, limiting their application in stretchable systems.
• Ultra-extensible systems are desirable for applications like flexible connectors, but stiff materials prevent necessary coiling within liquid drops.
• Existing drop-on-fiber systems achieve ultra-extensibility through fiber coiling, but this is incompatible with stiff functional materials.

Purpose of the Study:

• To overcome the limitation of stiff functional materials in ultra-extensible drop-on-fiber systems.
• To develop a composite system enabling in-drop coiling of functional fibers for enhanced stretchability.
• To demonstrate the transmission of information through an ultra-extensible composite system.

Main Methods:

• Attaching a soft elastomer beam to a stiff functional fiber to create a composite system.
• Developing a simple mechanical model to explain the in-drop coiling behavior of the composite system.
• Experimental validation using a micronic PEDOT:PSS conductive fiber joined to a PVS soft beam.

Main Results:

• The composite system exhibits in-drop coiling, overcoming the limitations of stiff functional materials.
• The addition of the soft beam significantly favors in-drop coiling, enabling ultra-extensibility.
• The composite system successfully conveyed electricity throughout a 1900% elongation, demonstrating its functional capability.

Conclusions:

• Attaching soft elastomer beams to functional fibers is an effective strategy to achieve ultra-extensible, information-carrying systems.
• The developed composite system demonstrates a novel approach for integrating electronic functionality with extreme mechanical stretchability.
• This work opens new avenues for designing advanced stretchable electronics and photonic devices.