基于面投影微立体光刻技术制备水凝胶柔性传感器件

柔性传感器是一类柔性材料制备的具有拉伸性、延展性、导电性的柔 性电子器件。柔性传感器件本身固有的可拉伸性，使其在被测对象发生变 形、弯曲、扭转等较大应变时仍旧能够正常工作。而通过将柔性材料与电 阻、电容、压电等电信号相结合，柔性传感器可以实现高度的智能化、集 成化和功能化，因此在可穿戴设备、柔性电子皮肤、人机界面和软体机器 人等领域有着广泛的应用。在柔性传感器的设计中，柔性电极材料的选取 是首要的问题。在众多的柔性材料中，离子导电水凝胶因其本征的柔性、 高度可拉伸性、优异的电导率及良好的生物兼容性在柔性传感领域展现出 极大的发展潜力。水凝胶是一类由高分子交联的三维聚合物网络构成的富 含水的柔性材料。通过水凝胶前驱体溶液与金属盐导电成分的混合掺杂， 水凝胶可轻易获得优良的离子导电能力。面投影微立体光刻技术（PµSL） 是一种基于区域投影触发光聚合的高分辨率 3D 打印技术，能够制造覆盖多 个尺度和多种材料的复杂三维结构，是基于光敏材料的柔性传感器优秀的 制备成形技术。 本文将面投影微立体光刻技术应用在水凝胶柔性传感器的制备上，通 过简化面投影微立体光刻打印工艺制备出牢固且坚韧的三明治式多层水凝 胶弹性体柔性应变传感器，不仅解决了传统制备方法耗时耗力的缺陷，同 时基于弹性体的包裹，水凝胶柔性传感器避免了失水信号偏移的问题，表 现出优异的动态响应特性和环境稳定性。本文分别将该应变传感器粘接到 3D 打印的软体气动驱动器和人手拇指关节上，前者成功实现了驱动器弯曲 角度与传感器的应变之间的线性映射，后者则证明了水凝胶柔性传感器优 异的阵列集成性能。从而大幅扩展了柔性传感器的应用场景和应用领域， 为下一代柔性传感器件的发展与规模化制造打下了坚实的基础。

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