A polycarboxylate dispersant for chlorantraniliprole suspension and its application

Abstract

The present invention provides a polycarboxylate dispersant for chlorantraniliprole suspension and its application, belonging to the field of organic synthesis. The dispersant is prepared by a method comprising the following steps: (1) dissolving an initiator in isopropanol as a reaction base, and then dropping styrene, methacrylic acid and polyether ER-30 into the base respectively, styrene, methacrylic acid and polyether ER-30 start dropping at the same time and the dropping speed is 2-3 drops / second, and the reaction is continued after the dropwise addition is completed; after the reaction is completed, vacuum drying or reduced pressure distillation is performed to remove the solvent to obtain a polycarboxylate; (2) the polycarboxylate obtained by step (1) is dissolved in water, and the pH value is adjusted to 5-7 to obtain a polycarboxylate dispersant for chlorantraniliprole suspension. When the polycarboxylate dispersant of the present invention is used for chlorantraniliprole suspension, the problem of easy paste and sinking to the bottom after heat storage is solved, the preparation process is simple, the raw materials are easy to obtain, and it is suitable for promotion to industrial production.

Description

Technical Field

[0001] The invention relates to the field of organic synthesis, and in particular to a polycarboxylate dispersant for a chlorantraniliprole suspension and application thereof. Background Art

[0002] Pesticide suspension concentrates are fine particles (generally with an average particle size of <5μm) of insoluble solid active ingredients of pesticides that are dispersed and suspended in a medium to form a stable suspended liquid product. Pesticide suspension concentrates do not have the dust problem of wettable powders, are not flammable or explosive, have small particle sizes, high biological activity, high specific gravity, and small packaging volumes. Compared with other pesticide formulations, pesticide suspension concentrates are safer and more environmentally friendly. Therefore, pesticide suspension concentrates have become the largest tonnage pesticide variety among new water-based pesticide formulations.

[0003] Dispersants are substances that can reduce the aggregation ability of solid (or liquid) particles in a dispersed system. It is a type of surfactant that can enhance and improve the dispersibility of solid or liquid materials when added to a dispersed system. Dispersants have a significant effect on the stability of pesticide suspensions, allowing the original drug particles to be evenly dispersed in a liquid medium (water, etc.) to avoid agglomeration of active ingredient particles and ensure the uniformity of the active ingredients in the agent; dispersants adsorbed on the surface of solid particles form charge or space steric barriers around the particles, thereby helping to prevent pesticide particles from aggregating again, playing a role in hindering or preventing the aggregation of solid particles in the dispersed system, and ensuring that the suspension remains evenly dispersed for a long time.

[0004] Chlorantraniliprole can effectively activate insect nicotinic acid (muscle) receptors, excessively release calcium ions in intracellular calcium stores, causing insect paralysis and death, and has high activity against larvae of lepidopteran pests, a wide insecticide spectrum, and good long-lasting effect. However, in the prior art, chlorantraniliprole suspension has the problem of easy paste and sinking to the bottom after hot storage. Summary of the invention

[0005] The invention provides a polycarboxylate dispersant for a chlorantraniliprole suspension. The dispersant has good dispersibility and stability. When used in the chlorantraniliprole suspension, the problem of easy paste formation and bottom sedimentation after heat storage is solved. The preparation process is simple, the raw materials are easily available, and the dispersant is suitable for promotion to industrial production.

[0006] The purpose of the present invention is achieved by the following technical solutions:

[0007] A polycarboxylate dispersant for a chlorantraniliprole suspension concentrate is prepared by a method comprising the following steps:

[0008] (1) dissolving an initiator in isopropanol as a reaction base, and then dropping styrene, methacrylic acid and polyether ER-30 into the base respectively, and dropping styrene, methacrylic acid and polyether ER-30 simultaneously at a rate of 2-3 drops / second, and continuing the reaction after the dropping is completed; after the reaction is completed, vacuum drying or reduced pressure distillation is performed to remove the solvent to obtain a polycarboxylate;

[0009] (2) dissolving the polycarboxylate obtained in step (1) in water and adjusting the pH value to 5-7 to obtain a polycarboxylate dispersant for chlorfenapyr suspension concentrate.

[0010] In the present invention, in step (1), the initiator is azobisisobutyronitrile; the amount of the initiator is 6-9% of the total mass of styrene, methacrylic acid and polyether ER-30; the molar ratio of styrene, methacrylic acid and polyether ER-30 is 1:0.9-1.1:0.9-1.1, and the dripping speed is the same.

[0011] In the present invention, the dropping speed of styrene, methacrylic acid and polyether ER-30 is 1-2 drops / second; during the process of adding styrene, methacrylic acid and polyether ER-30 into the reaction base material, the reaction base material is in a stirring state and the temperature is controlled at 82-85°C.

[0012] In the present invention, the reaction time after the dropwise addition in step (1) is 3.5-4.5 hours, the vacuum drying conditions are 78-82°C vacuum drying, and the reduced pressure distillation temperature is 63-67°C.

[0013] In the present invention, in step (2), sodium hydroxide is used to adjust the pH, and the mass percentage concentration of the solute in the polycarboxylate dispersant is 15-25%.

[0014] In the present invention, the number average molecular weight of the polycarboxylate dispersant is 34,000-36,000.

[0015] The present invention also provides application of the polycarboxylate dispersant in preparing chlorantraniliprole suspension concentrate.

[0016] The polycarboxylate dispersant of the present invention can be used in chlorantraniliprole suspension, and has the following beneficial effects:

[0017] (1) The polycarboxylate dispersant of the present invention introduces ER-30 into its molecular structure. ER-30 is different from general fatty alcohol polyoxyethylene ethers. Its structure contains not only ethylene oxide but also allyl glycidyl ether. Since allyl glycidyl ether has C=C, the anchor points on the molecular structure are increased, the dispersant's grip is improved, a three-dimensional barrier is formed, the aggregation between molecules is prevented, the physical stability of the suspension system is ensured, the application ability of the dispersant is significantly improved, and the market prospect is very broad.

[0018] (2) The polycarboxylate dispersant of the present invention is a polymer dispersant with cheap and readily available raw materials, mild reaction conditions, simple post-treatment, and easy industrial production.

[0019] (3) The polycarboxylate dispersant of the present invention is applied to 30% chlorfenapyr suspension concentrate, and has good dispersibility and stability, which effectively solves the problem that such products are easy to become paste-like and sink to the bottom after hot storage, and has a very broad application prospect in the pesticide adjuvant market. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The polycarboxylate prepared by Title 1 in Example 1 of the present invention 1 H NMR spectrum. DETAILED DESCRIPTION

[0021] Polyether ER-30: Using dodecanol as the initiator, it is a condensation product of dodecanol, allyl glycidyl ether and ethylene oxide, with an EO addition number of 4 and a number average molecular weight of 440. It was purchased from Jiangsu Zhongshan New Materials Co., Ltd.

[0022] AEO-5: fatty alcohol polyoxyethylene ether, which is a condensation product of dodecanol and ethylene oxide, with an EO addition number of 5 and a number average molecular weight of 484, purchased from Jiangsu Zhongshan New Materials Co., Ltd.

[0023] Example 1

[0024] 1. Preparation of polycarboxylate dispersants for chlorantraniliprole suspension concentrates

[0025] The preparation method of a polycarboxylate dispersant for a chlorantraniliprole suspension comprises the following steps:

[0026] (1) Preparation of polycarboxylate for chlorantraniliprole suspension: 12.9 g of azobisisobutyronitrile (0.08 mol) was dissolved in 23 g of isopropanol as a reaction base, 32.5 g of styrene (0.31 mol), 26.8 g of methacrylic acid (0.31 mol) and 136.4 g of polyether ER-30 (0.31 mol) were added dropwise into the reaction base using peristaltic benzene to carry out ternary copolymerization. During the addition, the base was stirred and the temperature of the base was controlled to be 83°C. Styrene, methacrylic acid and polyether ER-30 were added dropwise at the same time and the addition rate was 2 drops / second. After the addition was completed, the reaction was continued at 83°C for 4 hours. The obtained reaction solution was cooled to room temperature, transferred to a tray, and placed in a vacuum drying oven at 80°C for vacuum drying to remove excess solvent. After drying, the obtained white solid was the polycarboxylate for chlorantraniliprole suspension, and its number average molecular weight was 35,000. The polycarboxylates were subjected to structural characterization tests, and the results are shown in Figure 1In the polycarboxylate, the proton signals of the benzene ring are mainly concentrated in the low field region, i.e., around 7-8 ppm. The chemical shifts of the protons adjacent to C=O are mainly concentrated at 2-3 ppm, while the protons directly connected to the oxygen atom (mainly -CH 2 The chemical shift of the 2-hydroxy-1-(2-hydroxy-2-oxygen)-1-yl group was between 3 and 4 ppm, and the other methylene and methine signals were mainly between 1 and 2 ppm. Structural characterization further proved that the polycarboxylate was successfully synthesized.

[0027] (2) Preparation of polycarboxylate dispersant JPSC-10: 40 g of the polycarboxylate obtained in step (1) was dissolved in 155 g of distilled water, and 5 g of solid sodium hydroxide was added to adjust the pH value of the solution to 6 to obtain polycarboxylate dispersant JPSC-10.

[0028] The polycarboxylate dispersant JPSC-10 is used to prepare a 30% chlorantraniliprole suspension. The formula is as follows: 30g chlorantraniliprole original drug, 7g polycarboxylate dispersant JPSC-10, 3.6g magnesium aluminum silicate, 0.2g xanthan gum, 5g ethylene glycol, 0.3g organosilicon defoamer (SAG1572, purchased from Guangzhou Si Tuyuan Chemical Co., Ltd.), 0.3g sodium benzoate, and distilled water is made up to 100g. According to the formula, each substance is weighed, 100g zirconium beads are added, and the resulting mixture is placed in a vertical sand mill for ultrafine grinding, condensed water is connected, the grinding speed of the vertical sand mill is 2000r / min, the grinding time is 90min, and the material is discharged after ultrafine grinding and poured into a sealed glass bottle for storage.

[0029] 2. Preparation of the control dispersant SMAA

[0030] The preparation method of the control dispersant SMAA comprises the following steps:

[0031] (1) Preparation of control polycarboxylate: 12.9 g of azobisisobutyronitrile (0.08 mol) was dissolved in 23 g of isopropanol as a reaction base material, 32.5 g of styrene (0.31 mol), 26.8 g of methacrylic acid (0.31 mol), and 150 g of fatty alcohol polyoxyethylene ether AEO-5 (0.31 mol, purchased from Jiangsu Zhongshan New Materials Co., Ltd.) were added dropwise into the reaction base material using peristaltic benzene. During the addition process, the base material was in a stirring state and the temperature of the base material was controlled to be 83°C. Styrene, methacrylic acid, and fatty alcohol polyoxyethylene ether AEO-5 were added dropwise at the same time, and the addition rate was 2 drops / second. After the addition was completed, the reaction was continued at 83°C for 4 hours. The obtained reaction solution was cooled to room temperature, transferred to a tray, and placed in a vacuum drying oven at 80°C for vacuum drying to remove excess solvent. After drying, the obtained white solid was the control polycarboxylate, and its number average molecular weight was 20,000.

[0032] (2) Preparation of control dispersant SMAA: 40 g of control polycarboxylate was dissolved in 155.4 g of distilled water, and 4.6 g of solid sodium hydroxide was added to adjust the pH value of the solution to 6.0 to obtain control polycarboxylate dispersant SMAA.

[0033] A 30% chlorantraniliprole suspension concentrate containing a control dispersant SMAA was prepared according to the formula and preparation method of preparing a 30% chlorantraniliprole suspension concentrate using a polycarboxylate dispersant JPSC-10, the only difference being that 7g of the control dispersant SMAA was used to replace 7g of the polycarboxylate dispersant JPSC-10.

[0034] The 30% chlorfenapyr suspension prepared by using the dispersant JPSC-10 or the control dispersant SMAA was tested for the changes in effective ingredients, suspension rate and particle size after heat storage at 55° C. for 14 days. The results are shown in Table 1.

[0035] Table 1 Performance of each chlorantraniliprole suspension concentrate

[0036]

[0037] From the data in Table 1, it can be seen that when the polycarboxylate dispersant JPSC-10 and the control dispersant SMAA prepared by the present invention are used to prepare 30% chlorantraniliprole suspension, at an addition amount of 7%, the former has good heat storage performance, and the phenomenon of paste occurs before and after heat storage, the decomposition rate of the active ingredient of the original medicine is less than 5%, the suspension rate is higher than 99%, and the particle size does not increase. The comprehensive performance meets the national standard requirements for pesticide suspensions. However, the 30% chlorantraniliprole suspension prepared by the control dispersant SMAA has a paste phenomenon before and after heat storage, which is difficult to meet the preparation requirements of the chlorantraniliprole pesticide suspension, so it is not as good as the polycarboxylate dispersant JPSC-10 in terms of performance.

[0038] The performance test results of the 30% chlorfenapyr suspension concentrate show that the performance of the polycarboxylate dispersant JPSC-10 prepared by the present invention is significantly better than that of the control dispersant SMAA. This is because the polycarboxylate structure of JPSC-10 contains not only ethylene oxide chains but also allyl glycidyl ether. Since allyl glycidyl ether carries C=C, the anchor points on the molecular structure are increased, the dispersant's grip is improved, a three-dimensional barrier is formed, aggregation between molecules is prevented, and the physical stability of the 30% chlorfenapyr pesticide suspension concentrate formula is ensured.

[0039] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principles and purpose of the invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A polycarboxylate dispersant for a chlorantraniliprole suspension, characterized in that The method is prepared by the following steps: (1) The initiator is dissolved in isopropanol as a reaction base material, and then styrene, methacrylic acid and polyether ER-30 are added dropwise to the base material respectively. Styrene, methacrylic acid and polyether ER-30 are added dropwise at the same time and the dropping speed is 2-3 drops / second. After the addition is completed, the reaction is continued; after the reaction is completed, the solvent is removed by vacuum drying or reduced pressure distillation to obtain a polycarboxylate; (2) The polycarboxylate obtained in step (1) is dissolved in water and the pH value is adjusted to 5-7 to obtain a polycarboxylate dispersant for chlorantraniliprole suspension concentrate.

2. The polycarboxylate dispersant according to claim 1, characterized in that In step (1), the initiator is azobisisobutyronitrile; the amount of the initiator is 6-9% of the total mass of styrene, methacrylic acid and polyether ER-30; the molar ratio of styrene, methacrylic acid and polyether ER-30 is 1:0.9-1.1:0.9-1.1, and the dripping speed is the same.

3. The polycarboxylate dispersant according to claim 2, characterized in that The dropping speed of styrene, methacrylic acid and polyether ER-30 is 1-2 drops / second; during the process of adding styrene, methacrylic acid and polyether ER-30 into the reaction base material, the reaction base material is in a stirring state and the temperature is controlled at 82-85°C.

4. The polycarboxylate dispersant according to claim 2 or 3, characterized in that: After the dropwise addition in step (1) is completed, the reaction time is 3.5-4.5 hours, the vacuum drying conditions are 78-82°C vacuum drying, and the reduced pressure distillation temperature is 63-67°C.

5. The polycarboxylate dispersant according to claim 4, characterized in that In step (2), sodium hydroxide is used to adjust the pH, and the mass percentage concentration of the solute in the polycarboxylate dispersant is 15-25%.

6. The preparation method according to claim 5, characterized in that: The number average molecular weight of the polycarboxylate dispersant is 34,000-36,000.

7. Use of the polycarboxylate dispersant according to any one of claims 1 to 6 in the preparation of chlorantraniliprole suspension concentrate.

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