Preparation method of polyacrylamide specially used for agricultural fertilizer

Abstract

The invention discloses a preparation method of polyacrylamide specially used for agricultural fertilizer. The method comprises the following steps: placing polypropylene in a polymerization reactor,directly stirring under the normal pressure to polymerize the polypropylene, maintaining the constant temperature of polymerization to be within a range of 160-270 DEG C, and controlling the heat preservation time to be 0.5-5h; then, adding a catalyst-phosphoric acid into the material in a way of one-time addition or slow addition, and continuously performing the polymerization in the polymerization reactor under the normal pressure, wherein the constant temperature of the polymerization is within a range of 160-230 DEG C, and the heat preservation time is 0.5-5h; finally, carrying out alkaline hydrolysis. The mass ratio of the polypropylene to the catalyst-phosphoric acid is equal to 100 to (1-35), and the phosphoric acid is 85% phosphoric acid. The method provides by the invention guarantees the fluidity of the material, avoids the problem of material agglomeration, and can realize large-scale production. The phosphate ions in the catalyst are nutrient element needed for the growth of crops; the catalyst does not need to be separated, so that the processes such as washing are omitted, the production process is simplified, and the manufacturing cost is lowered.

Description

technical field [0001] The invention relates to a preparation method of polyacrylamide special for agricultural fertilizer. Background technique [0002] According to years of research by scientific workers, rational and economical fertilization is one of the important measures to increase crop yield and quality, so fertilization is the material basis for high yield and high quality. However, the low utilization rate of fertilizers has been perplexing the majority of agricultural workers. [0003] Polyacrylamide is a kind of amino acid polymer. In addition to the properties of water-soluble polymeric carboxylic acid, it also has the characteristics of easy degradation. type chemicals. Polyacrylamides with different molecular weights can be widely used in water treatment, fertilizer synergists, washing aids, cosmetics, hydrogels and other fields. As a fertilizer synergist, polyacrylamide has gradually been recognized by people for its excellent performance. [0004] The c...

AI Technical Summary

Problems solved by technology

[0004] The current technology is to add a catalyst at the initial stage of the reaction to speed up the polymerization reaction. Since the polymerized amino acid will come out of water during polymerization, plus the water brought in by the catalyst, the water will enter the material, causing the material to form a cohesive block. As the moisture evaporates from the material, the material gradually hardens, so it is difficult to achieve large-scale industrial production