Melamino-formaldehyde resin encapsulated acetamiprid microcapsule, and preparation method thereof

Abstract

The invention relates to a melamino-formaldehyde resin encapsulated acetamiprid microcapsule, and a preparation method thereof. The microcapsule is technically characterized by comprising the following components: melamine, a formaldehyde solution, acetamiprid, chloroform, an emulsifying agent, a dispersing agent, water, an acid catalyst and a base catalyst. The preparation method comprises the following steps of: putting melamine and the formaldehyde solution in a three-neck flask, adding the base catalyst and regulating, and heating to obtain a melamino-formaldehyde prepolymer; putting the acetamiprid, chloroform, the emulsifying agent, and water in a reaction flask, and stirring to obtain a pre-emulsification solution; mixing the pre-emulsification solution and the prepolymer, adding acid and catalyzing, and adding an appropriate amount of dispersing agent, raising temperature to 60 DEG C, reacting for three hours and stopping reaction; and washing a product by using water for multiple times, and suction-filtering and drying to obtain a microcapsule product. The encapsulation rate of the microcapsule is relatively high, sustained release time is long, pollution to environment is reduced, the preparation method is simple, wall materials are low in cost and the microcapsule is suitable for large-scale production and application.

Description

technical field [0001] The invention relates to an insecticide microcapsule and a preparation method thereof, in particular to a microcapsule with acetamiprid as a core material and a melamine-formaldehyde resin as a wall material and a preparation method thereof. technical background [0002] With the development of agriculture, the use of pesticides has increased and the area of ​​use has continued to expand. For general pesticide formulations, the phenomenon of loss, dispersion and decomposition is very serious, which not only causes waste, but also seriously pollutes the environment. For example, emulsifiable concentrate is the dosage form with the simplest preparation process and is widely used in our country. However, this dosage form contains a large amount of organic solvents, which brings problems such as pollution and flammability. In addition, some insecticides are unstable and easily decompose under high temperature or sunlight. Therefore, repeated application o...

AI Technical Summary

Problems solved by technology

[0005] 2. When used, it needs to be diluted with water to form an emulsion. The active ingredients are micron-scale dispersed. The dispersibility of the active ingredients is poor and the effective utilization rate is low, resulting in a large amount of pesticides, resulting in increased costs and a large amount of pesticide residues, which seriously affects the quality of agricultural products.

[0006] 3. The active ingredients have poor permeability, and the active ingredients remaining on the leaves are decomposed and wasted due to environmental factors such as light and air.

[0008] Chinese patent CN1491558A adopts emulsion polymerization to prepare acetamiprid water-suspended nanocapsules. The capsule has the function of controlled release, reduces the dosage of the drug, and reduces the pollution to the environment, but its drug loading rate is low, only 0.5-5 %; and in order to control the particle size of the capsule, the amount of emulsifier is not less than 7%, which greatly increases the production cost

Chinese patent CN101091494A uses glyphosate potassium salt as the core material and urea-formaldehyde resin as the wall material to prepare urea-formaldehyde microcapsules by in-situ polymerization. The preparation method of the microcapsules is simple and the encapsulation efficiency can reach about 80%. Rough, not smooth, and slow release effect is not very ideal

Chinese patent CN1927187A prepared microcapsules by coating dicyclopentadiene with melamine formaldehyde resin, which is mainly used for material self-repair. The microcapsules have better heat resistance and good sealing performance; Flame-retardant microcapsules prepared by phenylene ether have good compactness and good water resistance, but there is no patent report on microcapsules coated with pesticides, especially acetamiprid, using melamine-formaldehyde resin as the wall material. There is no patent report for melamine-formaldehyde resin-based microcapsules with amidine as the core material

Images