Ionically conductive hydrogels can be used to produce wearable devices because of their mechanical flexibility and intelligent sensing. However, utilizing petrochemical or synthetic materials via complex procedures remains a challenge to sustainability. Here we report a new simple strategy to fabricate a double network hydrogel from natural ingredients of corn starch and sodium alginate. Starch-alginate hydrogel exhibited porous microstructure and high strength which can be modulated by appropriate calcium ion concentration. Because of the hydrogen bond and ion crosslinking, the starch-alginate hydrogel could be restored to its original shape after being compressed, twisted and stretched. The hydrogel prepared with high amylose starch and sodium alginate with 0.4% (W/V) calcium ion addition had the highest breaking strength (281.51 kPa) and toughness (61.61 kJ/m³) at 160% strain. The third harmonic wave revealed the transition process between the formation and destruction of the hydrogel network structure. The conductive hydrogel can adhere to human skin to monitor different motions and vocal cord vibrations. Our research brings new inspiration to the design of environment-friendly wearable electronic devices which can be manufactured in large quantity at extremely low cost.

离子导电水凝胶可用于生产可穿戴设备，因为它们具有机械灵活性和智能传感功能。然而，通过复杂的程序利用石化或合成材料仍然是对可持续性的挑战。在这里，我们报告了一种新的简单策略，用玉米淀粉和海藻酸钠的天然成分制造双网络水凝胶。淀粉-海藻酸盐水凝胶具有多孔微结构和高强度，可通过适当的钙离子浓度进行调节。由于氢键和离子交联，淀粉-海藻酸盐水凝胶在压缩、扭曲和拉伸后可以恢复到原来的形状。用高直链淀粉和海藻酸钠制备的水凝胶具有最高的断裂强度（281.³ ) 在 160% 应变下。三次谐波揭示了水凝胶网络结构的形成和破坏之间的过渡过程。导电水凝胶可以粘附在人体皮肤上以监测不同的运动和声带振动。我们的研究为环境友好型可穿戴电子设备的设计带来了新的灵感，这些设备可以以极低的成本大量生产。