Ultra Stretchable Strain Sensors and Arrays with High Sensitivity and Linearity Based on Super Tough Conductive Hydrogels

Biocompatible conductive hydrogels with intrinsic flexibility, high sensitivity, linearity, and outstanding reliability are highly demanded for wearable devices or implantable sensors. Here we report novel tough conductive hydrogels comprised of interpenetrating polyaniline (PANI) and poly(acrylamide-co-hydroxyethyl methylacrylate) (P(AAm-coHEMA)) networks. Intrinsic interactions between the conductive PANI network and the flexible P(AAm-co-HEMA) endowed hydrogels with outstanding strength and toughness to cyclic loadings. The conductive hydrogels show very high sensitivity (gauge factor 11) and outstanding linear dependence of sensitivity on strain. Strain sensors based on the conductive hydrogels demonstrate reliable detection of repeated large strains and subtle vibrations, including the movements of various human joints, pulses and voiceprints. Moreover, a prototype 2D sensor array is fabricated to sense strains or pressures in the two dimensions, which is promising for electronic skin, touchpads, biosensors, human-machine interfaces, biomedical implants, wearable electronic devices and so on.
对于可穿戴设备或可植入传感器，非常需要具有固有柔韧性，高灵敏度，线性和出色可靠性的生物相容性导电水凝胶。在这里，我们报告了由互穿聚苯胺（PANI）和聚（丙烯酰胺 - 共 - 羟乙基甲基丙烯酸酯）（P（AAm-coHEMA））网络组成的新型坚韧导电水凝胶。导电PANI网络和柔性P（AAm-co-HEMA）之间的内在相互作用赋予水凝胶以优异的强度和韧性以承受循环载荷。导电水凝胶显示出非常高的灵敏度（标准系数11）和对应变的突出线性依赖性。基于导电水凝胶的应变传感器可以可靠地检测重复的大应变和微妙的振动，包括各种人体关节，脉冲和声纹的运动。此外，制造原型2D传感器阵列以感测二维中的应变或压力，这有望用于电子皮肤，触摸板，生物传感器，人机界面，生物医学植入物，可穿戴电子设备等。

CONCLUSION

In summary, we have prepared novel tough and fatigue resistant conductive hydrogels comprised of interpenetrating networks of polyaniline and P(AAm-co-HEMA). The hydrogels show high sensitivity (GF=11) at low strain and outstanding linearity at high strains. These unprecedented merits provide precise and reliable detections of subtle vital signals and human movements. An array of conductive hydrogel sensors are fabricated for two-dimension detection of tiny forces. These tough and conductive hydrogels may find broad applications in electronic skin, biomedical implants, human movement monitors, and so on.
总之，我们已经制备了新型坚韧且抗疲劳的导电水凝胶，其由聚苯胺和P（AAm-co-HEMA）的互穿网络组成。 水凝胶在低应变下显示出高灵敏度（GF = 11），在高应变下显示出优异的线性。 这些前所未有的优点可以精确可靠地检测微妙的生命信号和人体运动。 制造了一系列导电水凝胶传感器，用于微小力的二维检测。 这些坚韧且导电的水凝胶可广泛应用于电子皮肤，生物医学植入物，人体运动监测器等。