Research group of Dr. Yingying Zhang from Department of Chemistry and Center for Nano and Micro Mechanics (CNMM) of Tsinghua University (Beijing, China) made progress on stretchable textiles and published their work on ACS Appl. Mater. Interfaces.
As an important component of wearable electronics, stretchable conductors that could maintain high conductivity under various mechanical deformations has been extensively investigated. An intrinsically stretchable and highly conductive textile based stretchable conductor was developed by utilizing low-cost and mass-produced weft-knitted textiles (e.g. Modal textile) as raw materials through a simple thermal treatment. The unique weft-knitted structure and the pyrolysis induced formation of the graphite-like carbon fibers could be attributed to the unique mech-electrical property that the conductive textile either directly or after being encapsulated in an elastomer, was able to sustain large tensile strains while keeping stable electrical conductivity. More precisely, for a bare conductive textile, the relative variation of resistance is within 3% under strain up to 70%, while for a textile/Ecoflex composite, the variation is within 3% under strain up to 125%. As a proof of concept, stretchable supercapacitors and elastic thermal therapy devices could be fabricated by using the intrinsically stretchable and conductive textile, both of which showed superior performances. Considering the simplicity and large scalability of the thermal treatment process, the low cost and mass production of the raw textile materials, and the superior performances of the obtained conductive textiles, the strategy for stretchable conductors reported in this work, might pave a new way for the large-scale and cost-effective fabrication of elastic electronic textiles and contribute to the development and industrial production of wearable electronics.