Industrial preparation method of water-soluble resin coating material and application thereof

Abstract

The invention discloses a preparation method of a water-soluble resin coating material and an application thereof. The preparation method comprises the steps as follows: water and emulsifier are prepared into an emulsifier solution; part of the emulsifier solution and a mixed monomer are prepared into an emulsive monomer; and the rest of the emulsifier solution and the emulsive monomer react under the evocation of an evocating agent to obtain the coating material. The invention realizes a high-temperature coating process of water polymer and adopts industrial-scale equipment and process condition so as to be conveniently used for the manufacture of the controlled-release coating material of an enterprise without pilot test and technique magnification. The Tg temperature of the coating material is 15-100 DEG C, and agglomeration can not occur when the fluidization coating temperature reaches 100 DDG C.

Description

technical field [0001] The invention belongs to the technical field of preparation of agricultural controlled-release fertilizers, and in particular relates to an industrial preparation method and application of a water-soluble resin coating material. Background technique [0002] Under the guidance of the national policy of high efficiency, energy saving and environmental protection, the focus of energy saving and environmental protection in my country's agricultural production is how to effectively increase the utilization rate of chemical fertilizers and reduce the amount of chemical fertilizers used. According to the latest research reports, as an important means of agricultural production, chemical fertilizers account for 40-50% of my country's agricultural production investment. However, the seasonal utilization rate of chemical nitrogen fertilizers in field crops has been hovering at 30-35%, or even lower. The low utilization rate of chemical fertilizers not only caus...

AI Technical Summary

Problems solved by technology

If the existing water-based polymer products are directly used for fertilizer coating, although a complete film layer can be formed on the surface of the fertilizer, the construction industry, papermaking, and decoration industries mainly emphasize and require water-based polymers after film formation. Adhesion, air permeability, etc., cannot meet the requirements of manufacturing controlled-release fertilizers. If these emulsions are used directly to manufacture controlled-release fertilizers, it will not only be wasteful, but also coated fertilizers cannot meet the standards of controlled-release fertilizers at all.

The main problems are as follows: first, there are too many hydrophilic monomers and hydrophilic groups, and the coating layer completely absorbs water and swells in a short time and loses the controlled release performance; second, the emulsion with too small monomer molecules The film-forming temperature is too high, resulting in incomplete and discontinuous coating and increased energy consumption; third, the emulsion with too large monomer molecule is easy to stick back, and the coated fertilizer is easy to agglomerate, and the coating of the controlled-release fertilizer during the agglomeration breaking process If it is destroyed, the coated fertilizer loses its controlled release function

[0009] Chinese patent CN1939878A and related U.S. patents report that the above-mentioned commercial emulsion is used for coating, but the fertilizer surface must be pretreated before coating, and the pretreatment of the fertilizer surface will undoubtedly increase the complexity of the process, which is not conducive to achieving high efficiency, energy saving, and energy saving. industrialized production

Chinese patent CN101182269A aims at the problem of the above-mentioned fertilizer surface pretreatment, the emulsion is improved from the relationship between the polymerization method and conditions, the composition, performance, polymer structure and membrane material performance of the emulsion, but, with regard to the water-based polymer The synthesis process, monomer ratio, emulsifier selection and polymerization process all need to be improved

To sum up, there are still some fatal technical bottlenecks in the prior art: (1) the water whitening resistance (water resistance) of the existing commercial emulsion film formation is very poor, and the film formation will completely absorb water and swell in a few hours in water, losing its Controlled release performance; its Tg temperature is low, it is easy to agglomerate in the fluidized bed, and the fertilizer will stick together during the storage of the finished product; (2) In the coating process, commercial emulsions cannot meet the high temperature and non-stick requirements of the coating process at the same time. (3) Most of the current patented processes and methods are laboratory-scale processes, technologies and methods, which are difficult to be directly applied to the industrial production of controlled-release fertilizers; (4) still need to be processed before water-based polymer coating Fertilizer surface for pretreatment

There is no relevant technical report

Images