Accurate detection of minute external strains is crucial for the development of efficient strain‐responsive sensors. However, designing a recyclable strain‐responsive sensor that simultaneously combines high sensitivity at low strain levels, excellent mechanical properties, and cost‐effectiveness remains a significant challenge. In this study, a strain‐responsive sensor named Cu2+‐crosslinked conductive acrylic resin (PAV/Cu2+‐CB‐x) has been designed by integrating conductive carbon black (CB) into an acrylic resin matrix crossed by Cu2+ to form a hierarchical dynamic network. Molecular dynamics (MD) simulations reveal that this molecular structure consists of multilevel strong and weak dynamic bonds: weaker coordination bonds and hydrogen bonds endow this sensor with exceptional sensitivity to minor strains, while stronger ionic bonds ensure superior mechanical properties. This meticulous molecular design enables the PAV/Cu2+‐CB‐x to exhibit a tensile strength of 7.16 MPa, an elongation at break of 355.50%, high conductivity of 0.294 S cm−1, and excellent sensitivity under the strains below 5% (gauge factor = 8.24). Additionally, this PAV/Cu2+‐CB‐x demonstrates a remarkable tensile strength recovery rate of 95.35% after multiple recycling. When applied as a strain‐responsive sensor, it can precisely capture movements of human joints and throat activity. This work provides a promising solution for future applications in motion detection and voice recognition.

中文翻译：

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在低应变下通过多级强弱动态结构设计高应变响应和可回收的传感器


准确检测微小的外部应变对于开发高效的应变响应传感器至关重要。然而，设计一种可回收的应变响应传感器，同时兼具低应变水平下的高灵敏度、优异的机械性能和成本效益仍然是一个重大挑战。在这项研究中，通过将导电炭黑 （CB） 集成到 Cu2+ 交叉的丙烯酸树脂基体中，形成分层动态网络，设计了一种名为 Cu2+ 交联导电丙烯酸树脂 （PAV/Cu2+-CB-x） 的应变响应传感器。分子动力学 （MD） 模拟表明，这种分子结构由多级强动态键和弱动态键组成：较弱的配位键和氢键使该传感器对微小应变具有极高的灵敏度，而较强的离子键则确保了卓越的机械性能。这种细致的分子设计使 PAV/Cu2+-CB-x 表现出 7.16 MPa 的拉伸强度、355.50% 的断裂伸长率、0.294 S cm-1 的高导电性，以及在低于 5% 的应变下出色的灵敏度（标量系数 = 8.24）。此外，这种 PAV/Cu2+‐CB-x 在多次回收后表现出 95.35% 的显着拉伸强度恢复率。当用作应变响应传感器时，它可以精确捕捉人体关节的运动和喉咙活动。这项工作为未来运动检测和语音识别的应用提供了一个有前途的解决方案。