Self-healable flexible sensing materials are extensively investigated for their potential use in human motion detection, healthcare monitoring, and other fields. However, the existing self-healable flexible sensing materials have limited their application in real life due to the weak stability of the conductive network and the difficulty in balancing stretchability and self-healing performances. In this paper, a flexible sensor with skin-like properties was prepared by composing a polymer composite hydrogel with a multiple network structure consisting of polyaniline, polyvinyl alcohol, chitosan, and phytic acid. The composite hydrogel was tested and proved to own high mechanical properties (stretchability ≈ 565%, strength ≈ 1.4 MPa), good electrical conductivity (0.214 S cm–1), excellent self-healing properties (>99% healing efficiency in a 4 h healing period), and antibacterial properties. It had high sensitivity and a wide sensing range for strain and pressure, making it possible to manufacture multifunctional flexible sensors with comprehensive performance exceeding that of most flexible sensing materials. Notably, this polymer composite hydrogel can be manufactured in a large area and at a low cost, which is beneficial for its further application in many fields.

Currently, the excessive application of fertilizers and the random discharge of waste water, waste gas, and residues have led to more and more serious soil pollution problems. Zeolite is the most promising material for preparing a green and environmentally friendly soil conditioner. Herein, the carbon nanotubes/polydopamine/ZSM-5 composite soil conditioner was prepared by a facile two-step method, and it was used to release fulvic acid and adsorb methylene blue to improve the environment. The cumulative release rate of the composite soil conditioner was 52% within 430 h for fulvic acid, which had a good sustained release effect and could be sustained-released in different acid-based surroundings. In addition, it showed a good adsorption capacity of methylene blue, and it is about 80.02 mg/g which was about six times higher than that of ZSM-5. It was beneficial for the adsorption of methylene blue in a neutral environment. Finally, it could promote the growth of brassica chinensis and maize, and the promotion effect was 60 and 35%, respectively. Therefore, the carbon nanotubes/polydopamine/ZSM-5 composite soil conditioner is a green and efficient material, which provides a new strategy to solve the problem of soil pollution.

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The excessive use of chemical products in agricultural production has brought many problems such as water pollution, air pollution, soil acidification and eutrophication of water bodies. Biodegradable methylcellulose microcapsules are used as carriers to achieve pollution-free and intelligent controlled release of agricultural chemical products. Methylcellulose was used as a coating material, loaded with fulvic acid (FA) and attapulgite (ATP), and then prepared into microcapsules by spray drying. The preparation process had good repeatability, and the obtained microcapsules possessed uniform particle size distribution. Methylcellulose microcapsules showed good heat sensitivity during water absorption process. The water absorption ratio was more than 10 times that of its own weight at 25°C, and the swelling ratio was 5–7 times that of its own weight at 35°C. The microcapsules reduced the loss of FA nearly 50% during the leaching process. Planting experiments showed that the microcapsules had good biocompatibility and exhibited obvious positive effects on the wheat growth.