Stretchable electronic circuits can seamlessly conform to irregular and dynamic surfaces with high integration. However, current stretchable configurations typically have limited stretchability due to the lack of robust connections between soft interconnects and rigid electronics. Here, we printed highly stretchable metal–polymer conductors on thermoplastic elastomers as interconnects. We developed electronic vests with porous surfaces for rigid electronics and introduced polyester hot-melt adhesives to strengthen connections between soft interconnects and rigid electronics. After thermal bonding, the adhesive penetrates the porous surface of electronic vests, creating a mechanical interlock and providing an adhesion force of 8.34 N/cm for the connection (3× higher than conductive adhesives). Thus, rigid electronics of different sizes and different pin counts can form strong connections to soft interconnects, achieving a maximum strain tolerance of ~700% (10× higher than conductive adhesives). We achieved highly integrated ultra-stretchable displays that can withstand stretching up to 220% without dead pixels.
Yuwen Gai,Luyu Yang,Wei Shen,Fengyan Tan,Qingqing Yu,Lei Zhang,Dongping Sun
A flexible strain sensor for detecting human motion signals has been a research hotspot. However, it is still challenging to achieve a good balance between sensitivity, strain tolerance, and toughness. In this study, we present a piezoresistive strain sensor composed of ductile bacterial cellulose (BC) and highly conductive MXene (Ti3C2Tx) nanosheets by applying simple gel-casting. The hydrogel exhibits excellent mechanical properties owing to the physical crosslinking by hydrogen bonds between the rich hydroxyl groups of BC and the oxygen-containing functional groups on MXene, achieving a breaking strength of 2.52 MPa and a strain of 87%. MXene also exhibits excellent electrical conductivity and sensitivity for detecting strain-induced deformation. The hydrogel can cycle more than 200 times under tensile or compressive strain and has a superior strain detection limit of 0.05% and a response speed of 130 ms. Our sensor shows real-time stress sensing under different amplitudes of human motions, such as fingers, wrists, and elbows, and still maintains its sensing ability underwater. Overall, the hydrogel sensor does not require special instrumentation, modification, or crosslinking agents in preparation; provides high tensile strength and good biocompatibility; and retains response ability underwater. Therefore, the flexible conductive hydrogel has a good application potential in the field of wearable strain–stress sensors.
危险品化学品经营许可证（带存储）