Preparation method and application of dibromocyanoacetamide DBNPA aqueous preparation

Abstract

The invention relates to a preparation method and application of a dibromocyanoacetamide DBNPA water-based preparation, and belongs to the technical field of preparation of water-based preparations. In the preparation process, deionized water is firstly added, stirring is conducted at a certain stirring speed, then polyhexamethylene guanidine hydrochloride PHMG, a pH value stabilizer and an anti-freezing agent are sequentially added, after one auxiliary is added every time, the auxiliary is fully dispersed, then the next auxiliary is added, after all the components are added, all the components are fully mixed through stirring, and the anti-freezing agent is prepared. And ensuring that the solution reaches a clear and transparent state to obtain the dibromocyanoacetamide DBNPA water-based preparation disclosed by the invention.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of aqueous preparations, and relates to a preparation method and application of an aqueous preparation of dibromocyanoacetamide DBNPA. Background Art

[0002] 2,2-Dibromo-3-nitrilopropionamide, alias: 2,2-dibromo-3-azidopropionamide, English name: 2,2-Dibromo-3-Nitrilopropionamide, abbreviation: DBNPA, CAS number: 10222-01-2, EINECS number: 233-539-7, and the structural formula is as Figure 1 shown. Dibromocyanoacetamide (DBNPA) is a broad-spectrum and highly efficient industrial fungicide.

[0003] As a broad-spectrum and highly efficient biocide, it can quickly penetrate the cell membrane of microorganisms and act on certain protein groups, causing the normal oxidation-reduction of cells to stop, thereby causing cell death. At the same time, its branches can also selectively brominate or oxidize special enzyme metabolites of microorganisms, ultimately leading to the death of microorganisms.

[0004] At present, in the DBNPA products sold on the market, in addition to the powder (content ≥ 97%), there are also solvent-based products with a content of 20%, such as DOWICIL QK-20 of Dow Chemical, ACTICIDE DB20 of THOR, and BIOX BC40 of LANXESS. The formula contains about 60% of alcohols as solvents. At the same time, in the long-term storage process of existing preparation products, the pH value will show a downward migration. Generally, the original solution will drop from pH > 3 to pH < 1 in about 60 days, showing serious instability.

[0005] The present invention solves the problems of high energy consumption and high VOC of dibromocyanoacetamide (DBNPA) preparations that require a large amount of organic solvents as raw materials, and also solves the problem of unstable pH value of existing preparations. Summary of the Invention

[0006] The purpose of the present invention is to provide a preparation method and application of an aqueous preparation of dibromocyanoacetamide DBNPA, which has the characteristic of stable pH value.

[0007] The purpose of the present invention can be achieved by the following technical solutions: A preparation method of an aqueous preparation of dibromocyanoacetamide DBNPA, the formula of the aqueous preparation is, by mass percentage, dibromocyanoacetamide DBNPA 2.5% - 10%, polyhexamethylene guanidine hydrochloride PHMG 5% - 20%, pH value stabilizer 0.1% - 5%, antifreeze 0% - 10%, and the balance is deionized water. The preparation method of the dibromocyanoacetamide DBNPA aqueous preparation is as follows. S1: Add deionized water into a stirrer and start stirring at a stirring rate of 100 r / min. S2: While stirring, add polyhexamethylene guanidine hydrochloride PHMG, a pH value stabilizer, and an antifreeze agent respectively. After adding each auxiliary agent, wait for it to be fully dispersed before adding the next one to obtain mixture A. S3: Add dibromocyanoacetamide DBNPA powder into mixture A. After stirring evenly, increase the rotation speed to 300 r / min and stir for 6 - 8 h to obtain a clear and transparent liquid, which is the dibromocyanoacetamide DBNPA aqueous preparation.

[0008] Furthermore, the mass fraction of the added polyhexamethylene guanidine hydrochloride PHMG is 25%.

[0009] Furthermore, the pH value stabilizer is one or more of citric acid, sodium dihydrogen phosphate, and potassium dihydrogen phosphate.

[0010] Furthermore, the antifreeze agent is one or more of ethylene glycol, propylene glycol, glycerol, and isopropyl alcohol.

[0011] The application of a dibromocyanoacetamide DBNPA aqueous preparation. The preparation is applied to prevent the growth and reproduction of bacteria and algae in papermaking, industrial circulating cooling water, lubricating oil for metal processing, pulp, wood, coatings, and plywood. At the same time, it can be used as a slime control agent and is widely used in the pulp and circulating cooling water systems of paper mills.

[0012] Dibromocyanoacetamide DBNPA is insoluble in water. At 20 °C, through experiments, its solubility in water does not exceed 0.5 g. This product has good stripping performance, no foam during use, the liquid product is miscible with water in any ratio, and it is low in toxicity.

[0013] In the preparation process of the present invention, deionized water is added first and stirred at a certain stirring rate. Subsequently, polyhexamethylene guanidine hydrochloride PHMG, a pH value stabilizer, and an antifreeze agent are added in sequence. After adding each auxiliary agent, wait for it to be fully dispersed before adding the next one. This step-by-step addition method helps to ensure the uniform distribution of various auxiliary agents in the solution, thereby more effectively controlling the stability of the pH value. After adding all components, stir to fully mix each component. Especially after adding DBNPA powder, increase the stirring rate to a higher level and continue stirring for a period of time to ensure that the solution reaches a clear and transparent state. Sufficient stirring and mixing help to promote the interaction between various components, thereby further improving the stability of the pH value.

[0014] Polyhexamethylene guanidine hydrochloride (PHMG) is a broad-spectrum bactericide and an environmentally friendly multi-purpose new cationic polymer. It is easily soluble in water, and its aqueous solution is colorless and odorless. It has many excellent properties such as broad-spectrum high efficiency, low use concentration, no foam, no drug resistance, and biodegradability. It has been extremely widely used in the sterilization and mildew prevention of plant protection, medicine, industrial products, food, and daily necessities. Its bactericidal mechanism is as follows: The guanidine group has high activity, making the polymer positively charged and easily adsorbed by various bacteria and viruses that are usually negatively charged, thus inhibiting the splitting function of bacteria and viruses and causing bacteria and viruses to lose their reproductive ability. At the same time, it is a high-molecular polymer that can form a thin film to block the respiratory channels of microorganisms, causing the microorganisms to quickly suffocate and die.

[0015] DBNPA has a certain stability in aqueous solution, but its stability is greatly affected by the pH value. Under alkaline conditions, DBNPA is easily hydrolyzed and loses its activity. Therefore, by adding a suitable pH stabilizer, the solution can be kept relatively stable under acidic or neutral conditions, thereby extending the service life of DBNPA; PHMG is a broad-spectrum bactericide with excellent bactericidal performance and stability. Its compound use with DBNPA can produce a synergistic effect, improve the bactericidal effect, and broaden the bactericidal spectrum. At the same time, the addition of PHMG also helps to improve the stability of the entire preparation; in addition, the addition of the antifreeze in the present invention can improve the stability of the preparation under low-temperature conditions and prevent the separation or precipitation of components caused by freezing. This helps to maintain the uniformity and stability of the preparation, thereby ensuring its performance during use.

[0016] The buffer agents such as citric acid, sodium dihydrogen phosphate, and potassium dihydrogen phosphate used in the present invention can form conjugate acid-base pairs in the solution. When the concentration of hydrogen ions or hydroxide ions in the solution changes, these conjugate acid-base pairs can absorb or release the corresponding ions, thereby slowing down the change rate of the pH value. By adding auxiliary agents such as buffer agents, the present invention can adjust the balance state of ions in the solution, thereby offsetting the influence of external factors on the pH value to a certain extent.

[0017] The beneficial effects of the present invention: The preparation process of the present invention is simple and convenient for production, and the organic solvents are removed in the present invention, which is green, environmentally friendly, and low-carbon. Therefore, the aqueous preparation obtained by the present invention is safer at the same concentration, greatly reducing the irritation to the human body and more in line with various domestic and foreign regulations; the applicable system of the present invention is more extensive, and the application scope is expanded. The present invention uses the compound synergism of dibromocyanoacetamide and polyhexamethylene guanidine hydrochloride, with a broad bactericidal spectrum. Brief Description of the Drawings

[0018] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the drawings.

[0019] Figure 1Structural schematic diagram of dibromocyanoacetamide DBNPA. Detailed implementation manners

[0020] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following will, in combination with the attached drawings and preferred embodiments, elaborate in detail on the specific implementation manners, structures, features and their effects according to the present invention.

[0021] Formulation ratio 1: Dibromocyanoacetamide DBNPA 5%, Polyhexamethylene guanidine hydrochloride PHMG 10%, Citric acid 5%, Ethylene glycol 10%, Deionized water 70%; Formulation ratio 2: Dibromocyanoacetamide DBNPA 2.5%, Polyhexamethylene guanidine hydrochloride PHMG 5%, Sodium dihydrogen phosphate 2.5%, Propylene glycol 10%, Deionized water 80%; Formulation ratio 3: Dibromocyanoacetamide DBNPA 10%, Polyhexamethylene guanidine hydrochloride PHMG 20%, Potassium dihydrogen phosphate 0.1%, Antifreeze 0.0%, Deionized water 69.9%.

[0022] Example 1 S1: Add deionized water to the stirrer according to formulation ratio 1, and start stirring at a stirring rate of 100 r / min; S2: While stirring, add Polyhexamethylene guanidine hydrochloride PHMG, Citric acid and Ethylene glycol with a mass fraction of 25% respectively according to formulation ratio 1. After adding each auxiliary agent, wait for it to be fully dispersed before adding the next one to obtain mixture A; S3: Add dibromocyanoacetamide DBNPA powder to mixture A, after stirring evenly, increase the rotation speed to 300 r / min, and stir for 7 h to obtain a clear and transparent liquid, which is the aqueous preparation of dibromocyanoacetamide DBNPA.

[0023] Example 2 S1: Add deionized water to the stirrer according to formulation ratio 2, and start stirring at a stirring rate of 100 r / min; S2: While stirring, add Polyhexamethylene guanidine hydrochloride PHMG, Sodium dihydrogen phosphate and Propylene glycol with a mass fraction of 25% respectively according to formulation ratio 2. After adding each auxiliary agent, wait for it to be fully dispersed before adding the next one to obtain mixture A; S3: Add dibromocyanoacetamide DBNPA powder to mixture A, after stirring evenly, increase the rotation speed to 300 r / min, and stir for 8 h to obtain a clear and transparent liquid, which is the aqueous preparation of dibromocyanoacetamide DBNPA.

[0024] Example 3 S1: Add deionized water into the stirrer according to Formulation Ratio 3, and start stirring at a stirring rate of 100 r / min; S2: While stirring, add polyhexamethylene guanidine hydrochloride PHMG with a mass fraction of 25% and potassium dihydrogen phosphate respectively according to Formulation Ratio 3. After adding each auxiliary agent, wait until it is fully dispersed before adding the next one to obtain Mixture A; S3: Add dibromocyanoacetamide DBNPA powder into Mixture A. After stirring evenly, increase the rotation speed to 300 r / min and stir for 6 h to obtain a clear and transparent liquid, which is the dibromocyanoacetamide DBNPA aqueous preparation.

[0025] Comparative Example 1 In this comparative example, the pH value stabilizer is not added during the preparation process, and the remaining steps are the same as those in Example 1.

[0026] Perform pH value stability detection on the examples and comparative examples. Detect the pH values of the samples of Examples 1-3 and Comparative Example 1 at 2 h, 72 h, 168 h, 336 h, and 720 h. The experimental results are summarized in the following table.

[0027] From the above experiments, it can be seen that the aqueous preparation prepared by the present invention has better pH value stability.

[0028] The above are only the preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a dibromocyanoacetamide DBNPA aqueous preparation, characterized in that: The aqueous preparation comprises, by weight percentage, 2.5% to 10% of dibromocyanoacetamide DBNPA, 5% to 20% of polyhexamethyleneguanidine hydrochloride PHMG, 0.1% to 5% of pH stabilizer, 0% to 10% of antifreeze agent, and the balance is deionized water. The preparation method of dibromocyanoacetamide DBNPA aqueous preparation is as follows: S1: Add deionized water into the stirrer and start stirring at a stirring rate of 100 r / min; S2: adding polyhexamethyleneguanidine hydrochloride PHMG, pH stabilizer and antifreeze agent respectively while stirring, and adding the next additive after each additive is fully dispersed to obtain a mixture A; S3: Add dibromocyanoacetamide DBNPA powder to mixture A, stir evenly, increase the speed to 300 r / min, and stir for 6 to 8 hours to obtain a clear and transparent liquid, which is the dibromocyanoacetamide DBNPA aqueous preparation.

2. The method for preparing a dibromocyanoacetamide DBNPA aqueous preparation according to claim 1, wherein The mass fraction of the added polyhexamethyleneguanidine hydrochloride PHMG is 25%.

3. The preparation method of a dibromocyanoacetamide DBNPA aqueous preparation according to claim 1, wherein The pH stabilizer is one or more of citric acid, sodium dihydrogen phosphate, and potassium dihydrogen phosphate.

4. The preparation method of a dibromocyanoacetamide DBNPA aqueous preparation according to claim 1, wherein The antifreeze agent is one or more of ethylene glycol, propylene glycol, glycerol and isopropanol.

5. An application of a dibromocyanoacetamide DBNPA aqueous preparation, based on a preparation method of a dibromocyanoacetamide DBNPA aqueous preparation according to any one of claims 1 to 4, characterized in that, The preparation is used to prevent the growth and reproduction of bacteria and algae in papermaking, industrial circulating cooling water, lubricating oil for metal processing, pulp, wood, coating and plywood. It can also be used as a slime control agent and is widely used in paper mill pulp and circulating cooling water systems.

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