With the rapid development of flexible and wearable electronic devices, research on high-sensitivity strain sensors has been attracting much attention. Here, glutaraldehyde is used as a cross-linking reagent to precross-link poly(vinyl alcohol); then FeCl₃·6H₂O is added into the precross-linked poly(vinyl alcohol) to obtain composite films of FeCl₃@PVA after gelatinization and freeze drying. Elastic conductive films of polypyrrole@poly(vinyl alcohol) (PPy@PVA) are prepared by immersing FeCl₃@PVA into a solution of pyrrole in acetonitrile and water to complete the polymerization in situ. The effects of the concentrations of glutaraldehyde and FeCl₃·6H₂O on the film’s structure and properties have been studied in detail; the results show that the strain sensor prepared from the optimized film has excellent stretchability (strain up to 309.5%), mechanical property (tensile strength of 32.8 MPa), and relatively high sensitivity (gauge factor can reach 5.07 under 1.0% strain). It can be used to detect various tiny physiological signals, for example, detecting the number of pulse beats, bending of the knuckles at different frequencies, and recognizing the pronunciation of different words by vocal cord vibration. These good properties mean that this kind of PPy@PVA strain sensor has great application prospects in physiological monitoring.

中文翻译：

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使用可拉伸PPy @ PVA复合材料作为高灵敏应变传感器来监视分钟运动。

随着柔性可穿戴电子设备的飞速发展，对高灵敏度应变传感器的研究已引起广泛关注。在此，戊二醛被用作交联剂以预交联聚乙烯醇。然后将FeCl ₃ ·6H ₂ O加到预交联的聚乙烯醇中，在糊化和冷冻干燥后得到FeCl ₃ @PVA的复合膜。通过将FeCl ₃ @PVA浸入吡咯在乙腈和水中的溶液中以完成原位聚合反应来制备聚吡咯@聚乙烯醇（PPy @ PVA）的弹性导电膜。戊二醛和FeCl ₃ ·6H ₂浓度的影响O对薄膜的结构和性能进行了详细研究；结果表明，由优化膜制备的应变传感器具有优异的拉伸性（应变高达309.5％），机械性能（抗拉强度为32.8 MPa）和相对较高的灵敏度（在1.0％应变下应变系数可以达到5.07）。它可用于检测各种微小的生理信号，例如，检测脉搏数，以不同频率弯曲指关节，以及通过声带振动识别不同单词的发音。这些良好的性能意味着这种PPy @ PVA应变传感器在生理监测中具有广阔的应用前景。