Project Lead: Printable liquid metal - carbon nanotube composites with exceptional conductivity, stretchability, and self healing behavior

In this project, I designed a multimaterial soft composite ink designed for excellent printability, stretchability, conductivity, and self healing.

The ink’s polymer matrix was chosen to be a block-chain-copolymer styrene-isoprene-styrene (SIS). SIS is known to undergo a controlled gel transition upon exposure to toluene vapor that can be used to elicit a polymer-gel transition to facilitate both enhanced ink wetting to attached components and self-healing behavior.

Eutectic gallium indium (EGI) was selected as the primary conductor for its fluidic nature and ability to deform with limited mechanical resistance.

Ag flakes are added to further improve conductivity and interact with the EGI surfaces to produce a binding hinge effect that improves ink mechanics and formation of conductive pathways

Finally, CNTs are introduced to act as a conductive binder suffused throughout the SIS network, allow for lower Ag flakes concentrations and modify the LM oxide shell, leading to improved ink rheology.

Relevant Papers

Intrinsically soft printed electronics for digitally augmented human sensing and vision

Under Review in Nature Nanotechnology

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