Abstract It has great significance to develop a convenient and efficient method for hydrogels with adjustable electric and magnetic properties, which can be used in human activity monitoring and personal healthcare diagnosis field. However, it is a big challenge to balance the relationship between the conductive and magnetic categories so that electromagnetic hydrogels could be developed by an in-situ fabrication way. In this work, we firstly proposed a sequential in-situ route to form polypyrrole (PPy) and Fe3O4 nanoparticles (Fe3O4 NPs) in sequence within polyvinyl alcohol (PVA) matrix for the hybrid hydrogels with decent mechanical, conductive, and magnetic properties simultaneously, named as Fe3O4/PPy/PVA hydrogel. The as-prepared hybrid hydrogels exhibited continuous electrons transporting path and magnetic responsive properties. Specifically, a unique combination of high electrical conductivity (up to 1.95 ± 0.17 E−4 S cm−1), saturation magnetization (5.42 emu g−1) and greatly enhanced mechanical properties (tensile strength up to 575.03 ± 28.32 kPa, elasticity modulus up to 461.19 ± 24.75 kPa). More importantly, these hybrid hydrogels demonstrated potential applications in biomedical electronic devices, such as strain sensors and magnetic navigators.

中文翻译：

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连续原位合成具有优异机械、导电和磁响应性能的新型复合水凝胶

摘要 开发一种方便、高效的电、磁特性可调的水凝胶方法，可用于人体活动监测和个人健康诊断领域，具有重要意义。然而，平衡导电和磁性类别之间的关系是一个很大的挑战，以便可以通过原位制造方式开发电磁水凝胶。在这项工作中，我们首先提出了一种顺序原位途径，在聚乙烯醇（PVA）基质中依次形成聚吡咯（PPy）和 Fe3O4 纳米粒子（Fe3O4 NPs），用于同时具有良好机械、导电和磁性的混合水凝胶，命名为 Fe3O4/PPy/PVA 水凝胶。所制备的混合水凝胶表现出连续的电子传输路径和磁响应特性。具体来说，高电导率（高达 1.95 ± 0.17 E-4 S cm-1）、饱和磁化强度（5.42 emu g-1）和大大增强的机械性能（拉伸强度高达 575.03 ± 28.32 kPa，弹性模量高达461.19 ± 24.75 kPa)。更重要的是，这些混合水凝胶展示了在生物医学电子设备中的潜在应用，例如应变传感器和磁导航器。