阅读说明：本技术 一种瓜果蔬菜高效抗菌杀菌剂制备方法及其应用 (Preparation method and application of efficient antibacterial bactericide for melons, fruits and vegetables ) 是由 付贤树 叶子弘 俞晓平 崔海峰 张雅芬 夏文强 于 2019-09-05 设计创作，主要内容包括：本发明公开了一种瓜果蔬菜高效抗菌杀菌剂制备方法及其应用,该抗菌杀菌剂为接枝二氟苯官能团的聚乙烯胺高分子产品。制备方法包括以下步骤：(A)常温下将1重量份的聚乙烯胺充分溶解50～300份溶剂中,并加0.2～2重量份二氟苯甲酸完全溶解；(B)氮气下加0.2～2.0重量份偶联剂于20～70℃反应1～6个小时,用酸碱度调节剂控制体系pH值；(C)反应液透析袋分离1-5天,干燥得提纯产物；(D)加0.01～0.1重量份稀土作增效剂,混合均匀得终产品。可用于瓜果蔬菜的抗菌杀菌,对肠杆菌、革兰氏阴性细菌的抗菌杀菌效果显著,1 mg/L～10 mg/L下达100.0%杀菌率,残留率较低,不会对人畜的健康造成威胁。(The invention discloses a preparation method and application of a high-efficiency antibacterial bactericide for fruits and vegetables. The preparation method comprises the following steps: (A) fully dissolving 1 part by weight of polyvinylamine into 50-300 parts by weight of solvent at normal temperature, and adding 0.2-2 parts by weight of difluorobenzoic acid to completely dissolve; (B) adding 0.2-2.0 parts by weight of coupling agent under nitrogen to react for 1-6 hours at 20-70 ℃, and controlling the pH value of the system by using a pH value regulator; (C) separating the reaction solution by a dialysis bag for 1-5 days, and drying to obtain a purified product; (D) adding 0.01-0.1 weight part of rare earth as a synergist, and uniformly mixing to obtain a final product. The bactericidal composition can be used for antibacterial sterilization of fruits and vegetables, has obvious antibacterial and bactericidal effects on enterobacter and gram-negative bacteria, achieves 100.0% bactericidal rate under 1-10 mg/L, has low residual rate, and does not threaten the health of people and livestock.)

1. A preparation method of a high-efficiency antibacterial bactericide for fruits and vegetables is characterized by comprising the following steps:

(A) mixing and stirring 1 part by weight of polyvinylamine and 50-300 parts by weight of a solvent at normal temperature to fully dissolve the polyvinylamine; then adding 0.2-2 parts by weight of difluorobenzoic acid and completely dissolving;

(B) adding 0.2-2.0 parts by weight of coupling agent into the solution under the protection of nitrogen for reaction, wherein the reaction time is 1-6 hours, the reaction temperature is 20-70 ℃, and a pH value regulator is required to be used for controlling the pH value of a solution system in the reaction process;

(C) after the reaction is finished, collecting the reaction solution into a dialysis membrane for separation, wherein the separation time is 1-5 days, and then drying the solution;

(D) and adding 0.01-0.1 part by weight of rare earth serving as a synergist into the purified product, and uniformly mixing to obtain the final product.

2. The preparation method of the high-efficiency antibacterial bactericide for fruits and vegetables as claimed in claim 1, wherein the high-efficiency antibacterial bactericide is an antibacterial bactericide containing difluorobenzene functional group, and the preparation method is characterized in that: the solvent is one or a mixture of more of water, methanol, ethanol, N-dimethylformamide or isopropanol.

3. The method for preparing a high-efficiency antibacterial bactericide for fruits and vegetables as claimed in claim 1, wherein the pH value regulator is selected from one or more of hydrochloric acid, acetic acid, oxalic acid, sodium hydroxide, ammonia water and sodium bicarbonate, and the pH value of the reaction solution system should be kept between 3.0-10.0.

4. The method for preparing a high-efficiency antibacterial bactericide for melon, fruit and vegetable as claimed in claim 1, wherein said polyvinyl amine polymer grafted with difluorophenyl group is used as the high-efficiency antibacterial bactericide for melon, fruit and vegetable, and said coupling agent is preferably N, N' -dicyclohexylcarbodiimide, 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, diisopropylcarbodiimide.

5. The method for preparing efficient antibacterial bactericide for melons, fruits and vegetables as claimed in claim 1, wherein polyvinylamine polymer melons, fruits and vegetables grafted with difluorophenyl group is used as the efficient antibacterial bactericide, and the rare earth synergist is preferably lanthanum trichloride, cerium tetrachloride or neodymium chloride.

6. The difluorobenzene functional polyvinyl amine polymer antibacterial bactericide prepared by the method of any one of claims 1 to 4 belongs to the protection scope of the invention.

7. The method for preparing efficient antibacterial bactericide for fruits and vegetables as claimed in claim 1, wherein the optimal substitution degree of difluorobenzoic acid of the polyvinylamine molecule grafted with difluorobenzoic acid is 20-35% (molar ratio).

8. The polyvinyl amine polymer grafted with difluorobenzoic acid according to claim 5 or 6, which is used as an antibacterial and bactericidal agent for fruits and vegetables.

9. The method of claim 8, wherein the polyvinyl amine polymer antibacterial fungicide having difluorobenzene functional group comprises: the using concentration of the antibacterial bactericide is 1 mg/L-10 mg/L according to the difference of the colony number in the fruits and vegetables.

Technical Field

The invention relates to the field of preparation and application of agricultural and sideline products, in particular to a preparation method and application of a difluorobenzene functional group-containing polyvinylamine antibacterial bactericide.

Background

Along with the gradual improvement of the living standard of people, the requirements of people on sanitation and health are higher and higher, especially for the consumption of agricultural products. The antibacterial bactericide is a common agricultural and sideline product, and can play a role in inhibiting the growth of microorganisms and killing the microorganisms, thereby ensuring the quality of agricultural products. The existing antibacterial agents can be divided into three types, namely natural antibacterial agents, inorganic antibacterial agents and organic antibacterial agents.

Natural antimicrobial agents are less useful due to limitations in their antimicrobial effectiveness, stability, and price. Although inorganic antibacterial agents have the advantage of good heat resistance, they are expensive and have antibacterial activity-delaying properties, and their market is shrinking. Compared with inorganic products, the organic polymer antibacterial agent has the advantages of small dosage, strong antibacterial activity, good safety and stability, wide application range, small influence from external environment and the like due to larger molecular weight, and has larger and larger application market and wide attention and application in the field of agricultural and sideline products. Common organic antimicrobial agents include: quaternary ammonium salts, quaternary phosphonium salts, phenolic compounds, and the like. Therefore, the development of the novel polymer antibacterial agent meets the development requirement of the market and has great practical application value.

Disclosure of Invention

The invention aims to provide a preparation and application method of a high-efficiency antibacterial bactericide for melons, fruits and vegetables, which has the advantages of excellent performance, simple process and low cost.

In order to solve the technical problem, the invention grafts difluorobenzoic acid on a macromolecular polyvinylamine molecular skeleton through a grafting reaction, and then uses rare earth as a synergist for compounding. The method can effectively improve the capability of the antibacterial bactericide for killing germs in fruits and vegetables.

The invention is realized by the following technical scheme:

(A) mixing 1 part by weight of polyvinylamine and 50-300 parts by weight of a solvent at normal temperature and fully stirring to fully dissolve the polyvinylamine; then, 0.2 to 2 parts by weight of difluorobenzoic acid is added thereto and sufficiently dissolved in the solution.

(B) Adding 0.2-2.0 parts by weight of coupling agent into the solution under the protection of nitrogen for reaction for 1-6 hours at 20-70 ℃. During the reaction, pH regulator is used to control the pH value of the solution system.

(C) After the reaction is finished, the reaction solution is collected into a dialysis membrane for separation, the separation time is 1 to 5 days, and then the solution is dried.

(D) And adding 0.01-0.1 part by weight of rare earth serving as a synergist into the purified product, and uniformly mixing to obtain a final product.

The solvent is one or a mixture of more of water, methanol, ethanol, N-dimethylformamide or isopropanol.

The pH value regulator is one or more selected from hydrochloric acid, acetic acid, oxalic acid, sodium hydroxide, ammonia water and sodium bicarbonate. The pH value of the reaction solution system should be kept between 3.0 and 10.0.

The coupling agent is preferably N, N' -dicyclohexylcarbodiimide, 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride or diisopropylcarbodiimide.

The rare earth synergist is preferably lanthanum trichloride, cerium tetrachloride and neodymium chloride.

The optimal substitution degree of the phenylboronic acid group to the polyvinylamine is 20-35% (molar ratio).

The invention also provides a verification result of the product used as an antibacterial bactericide. The using concentration of the product is generally 1 mg/L-10 mg/L.

Compared with the prior art, the invention has the advantages that: the invention provides a preparation technology of a high-molecular antibacterial bactericide containing difluorobenzene functional groups, and the grafted product has strong inhibition capability on bacteria such as escherichia coli, gram-negative bacteria and the like and low residue rate, and does not threaten the health of people and livestock. Therefore, the product can be used as an antibacterial bactericide for agricultural and sideline products. In addition, the invention has the advantages of simple and mature process, low production cost and easy control of operation.

Detailed Description

The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto: