Thermosensitive methylcellulose spray-dried microcapsules as a controlled release carrier for soil management

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.