Integrated Reactive Inking: Silver-Amine Complex Enables Sensing Textiles via Dynamic Assembly

To address the critical issues of particle aggregation, high sintering temperature, and poor compatibility with textile substrates in conventional nanosilver inks, this study presents a high-performance reactive nanosilver conductive ink for textile substrates via a dual-strategy system integrating molecular precursor engineering and surfactant-mediated interface regulation. The ink employs a dynamic self-assembly precursor system based on “silver ammonia–citric acid–ascorbic acid (Ag-CA-AA)”, which enables precise control over the nucleation, growth, and dispersion of silver nanoparticles through electrostatic interactions and hydrogen bonding. Coupled with the “ in situ reduction-protection” mechanism, the ink exhibits outstanding low-temperature sintering activity, yielding a conductive network with a resistivity as low as 10 –5 Ω·cm after sintering at 180 °C. Meanwhile, the introduction of polyether-modified heptamethyltrisiloxane surfactant (S77) optimizes the interfacial interaction between the ink and the substrate, resolving the poor wettability and adhesion of traditional silver inks. Performance tests reveal that the conductive cotton yarn achieves a stable conductive network after five dipping-sintering cycles, with a resistance increase of only ∼3% after 100 bending cycles and excellent resistance recovery after 2 months of storage under natural environmental conditions. The flexible sensor based on Ag–S77 ink exhibits acceptable low hysteresis to large strain signals and sensitively captures subtle physiological signals, enabling multiscale monitoring. This dual-strategy design provides a practical route for developing functional conductive inks. The low-cost and scalable ink lays a material foundation for textile-based flexible sensors, boosting the industrial application of smart textiles in health monitoring and flexible electronics.