Isophorone‐Based Quaternary Compound Modified Graphene for Machine Washable Nonwoven Piezoresistive Sensors

An isophorone‐based quaternary compound with two positively charged polymer chains has been synthesized to modify charge‐neutral graphene without affecting its unique intrinsic properties. A highly scalable dip and dry coating method is employed to coat the textile‐based substrates without subsequent post‐treatment. The resultant electronic textiles exhibit remarkably low sheet resistance ≈140 Ω sq−1) after 10 washing cycles, which is considerably better compared to any reported graphene‐based e‐textiles without post‐treatment. Graphene‐based nonwoven piezoresistive sensors developed for wearable e‐textiles use this approach to exhibit an impressive piezoresistive sensitivity in the low‐pressure range of 0 to 40 Pa and display good repeatability after washing cycles. Hence this novel modification strategy is envisaged to have strong potential for multifunctional applications in next‐generation graphene‐based wearable e‐textiles. A highly conductive, incredibly flexible, and machine washable graphene‐based wearable e‐textile is presented. The graphene is modified with a self‐prepared quaternary compound to bond with the textile substrate. Even after 10 washing cycles, the graphene‐based wearable e‐textiles exhibit the lowest sheet resistance (≈140 Ω sq−1) ever recorded. As a piezoresistive sensor, this wearable e‐textile demonstrates scalability and versatility.