Preparation method of controlled-release degradable coating material

Abstract

The invention relates to a preparation method of controlled-release degradable coating material. The preparation method includes the steps of firstly, adding deionized water into starch, adding hydrogen peroxide, adding composite catalyst, and heating to 65 DEG C to allow for oxidizing reaction for 1.5h; secondly, adding sodium sulfite into reaction liquid, adding borax and hydroxymethyl cellulose, and allowing for crosslinking reaction for 40 minutes; thirdly, pasting, namely adding the sodium hydroxide into the reaction liquid, and heating to 90 DEG C to allow for pasting reaction for 30 minutes; fourthly, grafting, namely adding polyacrylamide into the reaction liquid of the step 3, allowing for reaction for 10 hours at 90 DEG C; fifthly, adding 20% PPM of acid into the reaction liquid, adjusting pH of the solution to 7-7.5 to obtain the coating material for fertilizer. The coating material prepared by the preparation method is applicable to surface coating for various fertilizer particles, application range of the coating material is widened greatly, use of the coating material is facilitated, and cost is saved for enterprises.

Description

technical field [0001] The invention belongs to the field of chemical fertilizers, and relates to the coating of chemical fertilizers, in particular to a preparation method of a slow-release degradable coating material. Background technique [0002] Fertilizer is one of the most important means of production in agricultural production and the material basis for the sustainable development of agriculture. In recent years, due to the loss and inefficient use of fertilizers, serious resource waste and huge economic losses have been caused, and more importantly, serious pollution has been caused to the human body, the atmosphere, soil and food. Therefore, how to improve the utilization rate of fertilizers and organically combine the application of fertilizers with the yield, quality and environmental protection of crops has become the focus of special attention in the field of fertilizer research. [0003] At present, chemically synthesized slow-release fertilizers represented ...

AI Technical Summary

Problems solved by technology

[0003] At present, chemically synthesized slow-release fertilizers represented by urea-formaldehyde are currently the most mature and widely used slow-release fertilizers; although adding urease inhibitors or nitrification inhibitors to steady-state fertilizers can improve fertilizer utilization, it cannot prevent The leaching of fertilizers; the amount of sulfur in sulfur-coated urea is large, the nutrients inside it are not easy to overflow, and the coating layer is easy to oxidize and break, and long-term use will cause acidification of the soil; the sealing of inorganic mineral salt-coated slow-release fertilizers Poor, the nutrients are easy to dissolve quickly, and the film layer is easy to fall off; the slow-release performance of the organic polymer coating is very good, but the solvent used in its production and the coating material itself are not degradable, which brings difficulties to its production and application. to environmental pollution