Liquid metal composites with ultra-low loading, environmental adaptability, excellent adhesion, and closed-loop recyclability.

Conductive polymer composites are essential for emerging flexible and wearable electronics. However, achieving high conductivity, environmental robustness, and recyclability in conductive composites at low filler loading remains a significant challenge. Here, we introduce a dynamic covalently crosslinked polyurethane network whose temporary processing window regulates liquid metal sedimentation and evaporation induced coalescence, enabling continuous conductivity without post activation, robust adhesion, and extreme environmental adaptability. The processing window of the activated dynamic polymer network facilitates the coalescence of microdroplets into stable conductive channels at a low loading of 30 wt.%, yielding an electrical conductivity exceeding 10⁶ S m-1 after processing optimization. The composite maintains stable electrical and mechanical performance across temperatures ranging from -196 °C to 120 °C, during prolonged chemical exposure, and under sustained mechanical stress. Furthermore, the dynamic covalent network enables the efficient recovery of more than 95% of the liquid metal, while reconstruction of the network largely restores the original performance. This materials design addresses the longstanding trade-off among conductivity, durability, and recyclability and offers a scalable, sustainable platform for high-performance flexible and wearable electronics.