CN110800735B

CN110800735B - Microemulsion with emamectin benzoate as effective component and preparation method thereof

Info

Publication number: CN110800735B
Application number: CN201910968856.0A
Authority: CN
Inventors: 吴丽文; 夏姗姗; 张坤成; 王爱臣; 廖联安
Original assignee: Huizhou Yinnong Technology Co ltd
Current assignee: Huizhou Yinnong Technology Co ltd
Priority date: 2019-10-12
Filing date: 2019-10-12
Publication date: 2020-12-11
Anticipated expiration: 2039-10-12
Also published as: CN110800735A

Abstract

The embodiment of the invention discloses a microemulsion taking emamectin benzoate as an active ingredient, and relates to the technical field of pesticides. The microemulsion taking the emamectin benzoate as the effective component comprises the following components in percentage by mass: 5.7% of emamectin benzoate, 15-30% of solvent, 10-20% of surfactant, 0.5-5% of synergist, 1-5% of antifreezing agent, 0.1-2% of stabilizer and water to supplement to 100%, wherein the weight ratio of the synergist is 1-3: 2-4 of alkyl glycoside and isomeric alcohol polyoxyethylene ether. The microemulsion of the invention uses environment-friendly solvent, has the characteristics of stable performance and obvious control effect, and solves the problems of environment unfriendliness and unsafe use of the solvent used by the existing microemulsion.

Description

Microemulsion with emamectin benzoate as effective component and preparation method thereof

Technical Field

The embodiment of the invention relates to the technical field of pesticides, and particularly relates to a microemulsion taking emamectin benzoate as an active ingredient and a preparation method thereof.

Background

Emamectin benzoate (emamectin benzoate for short) is white or light yellow crystalline powder, is soluble in acetone and ethyl acetate, slightly soluble in water, and insoluble in hexane. Is prepared from the fermented product abamectin B₁The novel high-efficiency semi-synthetic antibiotic pesticide has the characteristics of super-high efficiency, low toxicity (the preparation is nearly nontoxic), low residue, no public nuisance and other biological pesticides. Is widely used for preventing and controlling various pests on crops such as vegetables, fruit trees, cotton and the like.

Except for a few pesticide raw materials which have high volatility and excellent water solubility and can be directly used, most pesticide raw materials need to be processed into various dosage forms for use. Microemulsion (formulation code ME) is called water-based emulsifiable concentrate or soluble emulsifiable concentrate, and is composed of raw pesticide, solvent, surfactant and other auxiliary agents, and liquid or solid raw pesticide is uniformly dispersed in water by means of the solubilization action of surfactant to form a transparent or semitransparent, stable over time and thermodynamically stable single-phase dispersion system. The microemulsion is mainly characterized in that: a. the emulsion has particles smaller than 100nm, and has the characteristics of good permeability, high absorptivity and high bioactivity; b. water is used as a dispersion medium, so that the packaging is easy, and the packaging container is not corroded; c. organic solvent is not used or is used less, the flash point is higher, the material is nonflammable, the transportation and the storage are safer, and the harm to people and environment when the organic solvent is produced and used is avoided; d. the processing technology is simple and has the characteristic of good stability over time. Microemulsion is known as green pesticide formulation, has the advantages of good pesticide effect, no or little use of organic solvent, little environmental pollution and the like, and is one of the directions for researching pesticide formulations.

The preparation of microemulsion has a great relationship with the effective components, and different kinds of pesticides have different stability in aqueous medium and different required auxiliaries. Chinese patent application CN 101449680a discloses a methylamino abamectin benzoate microemulsion and a preparation method thereof, the microemulsion comprises methylamino abamectin benzoate, a solvent, a cosolvent, a surfactant, a synergist, a stabilizer and water, the microemulsion prepared by the invention can obviously improve the drug effect, and has stable performance, but the used solvents are aromatic hydrocarbon solvents, cyclohexanone, dimethylformamide and acetone, which have great toxicity to human bodies and cause pollution to the environment.

With the continuous enhancement of environmental awareness and safety knowledge of people, the research and development of the microemulsion which is safe to use, environment-friendly, good in stability and remarkable in control effect has important significance.

Disclosure of Invention

Therefore, the embodiment of the invention provides the microemulsion taking the emamectin benzoate as the effective component and the preparation method thereof, the microemulsion uses an environment-friendly solvent, has the characteristics of stable performance and obvious control effect, and solves the problems of environment unfriendliness and unsafe use of the solvent used by the existing microemulsion.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

according to a first aspect of the embodiments of the present invention, the present invention provides a microemulsion with emamectin benzoate as an active ingredient, which comprises the following components by mass: 5.7% of emamectin benzoate, 15-30% of solvent, 10-20% of surfactant, 0.5-5% of synergist, 1-5% of antifreezing agent, 0.1-2% of stabilizer and water to supplement to 100%, wherein the weight ratio of the synergist is 1-3: 2-4 of alkyl glycoside and isomeric alcohol polyoxyethylene ether.

Further, the solvent is selected from one or more of ethanol, alcohol ether environment-friendly solvent, n-butanol, ethyl acetate, sec-butyl acetate and dimethyl sulfoxide.

Further, the surfactant is one or a combination of more than two of castor oil polyoxyethylene ether, fatty amine polyoxyethylene ether, calcium alkyl benzene sulfonate, nonionic ethylene oxide block copolymer and alkylphenol formaldehyde resin polyoxyethylene ether.

Further, the antifreezing agent is selected from one or more of glycerol, propylene glycol and polyethylene glycol.

Further, the stabilizer is selected from one or more of tert-butyl hydroquinone, dibutyl hydroxy toluene and epoxy chloropropane.

Further, the water is selected from tap water, distilled water or deionized water.

According to a second aspect of the embodiments of the present invention, the present invention provides a preparation method of the above microemulsion with emamectin benzoate as an effective component, the method includes the following steps:

dissolving emamectin benzoate and a stabilizer by using a solvent, stirring after the emamectin benzoate and the stabilizer are fully dissolved, adding a surfactant, a synergist and an antifreeze while stirring, slowly adding water into the mixed solution after uniformly mixing, and fully stirring to obtain the microemulsion taking the emamectin benzoate as an effective component.

The embodiment of the invention has the following advantages:

1. the invention takes emamectin benzoate as a raw pesticide, and the microemulsion emulsion prepared by screening and compounding the types of the surfactant, the synergist, the stabilizer, the antifreezing agent and the solvent has qualified stability, heat storage stability and low temperature stability, and has wide transparent temperature range.

2. The invention screens the synergist, avoids the influence of the addition of the synergist on the performance of the surfactant and the like, can simultaneously reduce the surface tension (diluted by 300 times) of the preparation to be less than or equal to 30mN/m and reduce the penetration time (diluted by 500 times) to be less than 20min, improves the utilization rate of the preparation in use and improves the drug effect.

3. The invention uses the solvent with lower toxicity, reduces the health hazard to users, reduces the pollution to the environment, and has environment friendliness and good safety.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The microemulsion taking emamectin benzoate as an effective component comprises the following components:

5.7kg of emamectin benzoate;

20kg of ethanol;

12kg of castor oil polyoxyethylene ether and 6kg of alkylphenol formaldehyde resin polyoxyethylene ether;

1kg of alkyl glycoside and 1kg of isomeric alcohol polyoxyethylene ether;

3kg of glycerol;

1kg of tert-butyl hydroquinone;

the tap water is supplemented to 100 kg.

The preparation method comprises the following steps:

The following examples and comparative examples were prepared in the same manner as in example 1.

Example 2

5.7kg of emamectin benzoate;

6kg of ethyl acetate and 9kg of n-butanol;

15kg of fatty amine polyoxyethylene ether and 5kg of calcium alkyl benzene sulfonate;

1kg of alkyl glycoside and 2kg of isomeric alcohol polyoxyethylene ether;

5kg of propylene glycol;

0.5kg of epoxy chloropropane;

the deionized water is supplemented to 100 kg.

Example 3

5.7kg of emamectin benzoate;

8kg of ethyl acetate and 16kg of alcohol ether environment-friendly solvent;

12kg of castor oil polyoxyethylene ether and 6kg of nonionic hydroxy polyethylene oxide block copolymer;

0.3kg of alkyl glycoside and 1.2kg of isomeric alcohol polyoxyethylene ether;

5kg of propylene glycol;

1kg of butylated hydroxytoluene;

the tap water is supplemented to 100 kg.

Example 4

5.7kg of emamectin benzoate;

10kg of dimethyl sulfoxide and 20kg of n-butyl alcohol;

9kg of fatty amine polyoxyethylene ether and 6kg of alkylphenol formaldehyde resin polyoxyethylene ether;

1kg of alkyl glycoside and 3kg of isomeric alcohol polyoxyethylene ether;

3kg of polyethylene glycol;

1kg of tert-butyl hydroquinone;

the distilled water is supplemented to 100 kg.

Example 5

5.7kg of emamectin benzoate;

16kg of alcohol ether environment-friendly solvent;

10kg of nonionic ethylene oxide block copolymer;

0.3kg of alkyl glycoside and 0.2kg of isomeric alcohol polyoxyethylene ether;

1kg of polyethylene glycol;

0.5kg of butylated hydroxytoluene;

the tap water is supplemented to 100 kg.

Example 6

5.7kg of emamectin benzoate;

22kg of sec-butyl acetate;

10kg of calcium alkyl benzene sulfonate and 5kg of alkylphenol formaldehyde resin polyoxyethylene ether;

2kg of alkyl glycoside and 2.6kg of isomeric alcohol polyoxyethylene ether;

3kg of polyethylene glycol;

1.5kg of epoxy chloropropane;

the tap water is supplemented to 100 kg.

Comparative example 1

The comparative example differs from example 3 only in that a synergist was used, the synergist of the comparative example being 1.5kg of an alkyl glycoside.

Comparative example 2

The difference between the comparative example and the example 3 is only that the synergist is different, and the synergist of the comparative example is 1.5kg of isomeric alcohol polyoxyethylene ether.

Comparative example 3

The difference between the comparative example and the example 3 is only that the synergist is adopted, and the synergist of the comparative example comprises 1.2kg of alkyl glycoside and 0.3kg of isomeric alcohol polyoxyethylene ether.

Comparative example 4

The comparative example differs from example 3 only in that the surfactants used were different, and the surfactants of the comparative example included 12kg of triphenylethylphenol polyoxyethylene ether and 6kg of fatty alcohol polyoxyethylene ether.

Comparative example 5

The difference between the comparative example and the example 3 is only that the contents of the components are different, and the microemulsion taking the emamectin benzoate as the effective component comprises the following components:

5.7kg of emamectin benzoate;

25kg of ethyl acetate and 10kg of alcohol ether environment-friendly solvent;

15kg of castor oil polyoxyethylene ether and 8kg of alkylphenol formaldehyde resin polyoxyethylene ether;

0.3kg of alkyl glycoside and 1.2kg of isomeric alcohol polyoxyethylene ether;

6kg of propylene glycol;

dibutylhydroxytoluene 2.4kg

The tap water is supplemented to 100 kg.

Test example 1

Stability test of microemulsion

Emulsion stability test: the method is carried out according to GB/T1603-2001. Adding 100mL (30 +/-2) DEG C standard hard water into a 250mL beaker, sucking 0.5mL of sample by using a pipette, and slowly adding hard water (200 times of dilution) under the condition of continuously stirring to prepare 100mL of emulsion; stirring at 2-3r/s for 30s, immediately transferring the emulsion into a clean and dry 100mL measuring cylinder, placing the measuring cylinder in a constant-temperature water bath, and standing for 1h at the temperature of (30 +/-2) ° C; and (4) taking out the measuring cylinder, observing the separation condition of the emulsion, and judging that the stability of the emulsion is qualified if no floating oil (paste) or precipitate is separated out in the measuring cylinder.

And (3) testing the heat storage stability: according to GB/T19136-2003. Injecting about 30mL of sample into a clean glass bottle by using an injector (the sample is prevented from contacting the bottle neck), placing the glass bottle in a thermostat at (54 +/-2) DEG C for 14 days, taking out the glass bottle after 14 days, and measuring the heat storage decomposition rate of the emamectin benzoate by adopting high performance liquid chromatography within 24 hours.

Low-temperature stability test: according to GB/T19137-2003. Transferring 100mL of sample into a centrifuge tube, cooling to (0 +/-2) ° C in a refrigerator, keeping the centrifuge tube and the content at (0 +/-2) ° C for 1h, stirring once every 15min for 15s, checking and recording whether solid or oily substances are separated out. Placing the centrifugal tube back to the refrigerator, and continuously placing at (0 +/-2) DEG C for 7 d; after 7d the tube was removed, allowed to stand at room temperature (no more than 20 ℃) for 3h and centrifuged for 15min to record the volume of the educt at the bottom of the tube (to the nearest 0.05 mL).

Transparent temperature range test: according to HG/T2467.10-2003. Taking 10mL of sample in a 25mL test tube, stirring the sample up and down by using a stirring rod, and gradually cooling the sample on an ice bath until the sample is turbid or frozen, wherein the temperature of the turning point is the lower limit t of the transparent temperature₁Then placing the test tube in a water bath, slowly heating at the speed of 2 ℃/min, and recording the temperature when the turbidity appears, namely the upper limit t of the transparent temperature₂The transparent temperature range is t₁～t₂。

The microemulsions of examples 1-6 of the present invention and comparative examples 1-5 were tested for emulsion stability, heat storage stability, low temperature stability and clear temperature range and the results are shown in table 1.

TABLE 1

As can be seen from table 1, the emulsion stability, the heat storage stability and the low temperature stability of the samples of examples 1 to 6 are all qualified, and the transparent temperature range is wide, which indicates that the microemulsion of the examples of the present invention has stable performance, further, comparing example 3 with comparative examples 1 to 5, the heat storage decomposition rate of the emamectin benzoate of example 3 is lower than that of other comparative examples, and the transparent temperature range is wider than that of other comparative examples, which indicates that the synergist and the surfactant of the examples of the present invention have important significance for widening the heat storage stability and the transparent temperature range of the microemulsion.

Physical and chemical property measurement of microemulsion

The sample was diluted 300 times and its surface tension was measured by a platinum plate method using an a101 surface tension meter.

Penetration time: by referring to HG/T2575-.

The microemulsions of examples 1-6 of the present invention and comparative examples 1-5 were tested for surface tension and permeation time and the results are shown in table 2.

TABLE 2

Sample (I)	Surface tension value, mN/m	Penetration time, min
			Example 1	28.18	11
Example 2	26.98	9
			Example 3	25.43	6
Example 4	28.13	12
			Example 5	28.99	15
Example 6	27.89	10
			Comparative example 1	30.12	18
Comparative example 2	31.32	16
			Comparative example 3	31.15	17
Comparative example 4	32.15	22
			Comparative example 5	30.12	20

As can be seen from Table 2, the surface tension values of the samples of examples 1-6 are lower than those of comparative examples 1-5, and the permeation time is shorter than that of comparative examples 1-5, which shows that the microemulsion of the examples of the invention can effectively reduce the surface tension of the liquid medicine, reduce the permeation time, improve the utilization rate, enable the product to rapidly spread on the surface of crops and form a layer of medicine film, and increase the spreading, permeation and other capabilities of the surface of the liquid medicine, thereby improving the control effect.

Test example 2

Field control effect test of microemulsion

The micro-emulsion of the embodiment 1 to 6 is used as a test medicament, the micro-emulsion of the comparative example 1 to 5 and a commercial product of 5.7 percent of emamectin benzoate are used as a contrast medicament, the medicament application dosage and the medicament application dosage are shown in a table 3, a clear water blank is set as a contrast, cowpea thrips prevention effect test is carried out, 13 treatments are carried out, each treatment is repeated for 4 times, 72 cells are totally carried out, and the area of each cell is 20m²The cells are arranged in random blocks.

TABLE 3

Numbering	Medicament	The dosage (preparation dosage) of the drug is gram/mu	Application rate (active ingredient) g/hectare
				1	Example 1	75	56.25
2	Example 2	75	56.25
				3	Example 3	75	56.25
4	Example 4	75	56.25
				5	Example 5	75	56.25
6	Example 6	75	56.25
				7	Comparative example 1	75	56.25
8	Comparative example 2	75	56.25
				9	Comparative example 3	75	56.25
10	Comparative example 4	75	56.25
				11	Comparative example 5	75	56.25
12	Commercially available product	75	56.25
				13	Clean water	--	--

Diluting the mixture with water according to the design dosage of the medicament test to obtain uniform liquid medicine, and uniformly spraying the liquid medicine by using a manual sprayer in the cowpea growing period (namely the flowering pod period).

The base number of the pre-drug investigation was determined, and 4 investigations were performed 1, 3 and 7 days after the pre-drug investigation. According to the pesticide field efficacy test criterion, 10 plants are randomly investigated in each district, 3 flowers at the middle and upper parts of each plant are selected, and the number of thrips in 30 flowers is recorded in each district.

The crater reduction rate and the control effect are calculated according to the following formulas, and the significance of each treatment is analyzed by a Duncan new repolarization method.

Percent reduction rate (%) is (number of live insects before application-number of live insects after application)/number of live insects before application x 100

Control effect (%) (% insect population reduction rate of treatment group-insect population reduction rate of control group) (100-insect population reduction rate of control group) × 100

During the test period, the cowpea grows normally, and no phytotoxicity symptoms such as leaf withering, dwarfing, green loss, deformity and the like appear, which shows that the microemulsion of the embodiment of the invention has no phytotoxicity to the cowpea.

The results of the efficacy test of each agent are shown in table 4.

TABLE 4

Note: the control effect in the above table is the average value of each repetition

As can be seen from table 4, the control effect of the microemulsion of the embodiment of the present invention on cowpea thrips is at least 83.69% 1 day after application, which is higher than the control effects of the comparative example and the commercially available products, and the control effect of the microemulsion of the embodiment of the present invention on cowpea thrips is at least 85.23% 3 days after application, which is higher than the control effects of the comparative example and the commercially available products, and the control effect of the microemulsion of the embodiment of the present invention on cowpea thrips is at least 74.88% 7 days after application, which is higher than the control effects of the comparative example and the commercially available products, wherein the microemulsion of the embodiment 3 has more reasonable component matching and stronger compounding effect, and has high control effect and significant difference in 1 day after application compared with other embodiments and comparative examples, and 3 days and 7 days after application, and has high control effect and significant difference compared with other embodiments, comparative examples and commercially available products.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. The microemulsion taking emamectin benzoate as an active ingredient is characterized by comprising the following components in percentage by mass: 5.7% of emamectin benzoate, 15-30% of solvent, 10-20% of surfactant, 0.5-5% of synergist, 1-5% of antifreezing agent, 0.1-2% of stabilizer and water to supplement to 100%, wherein the weight ratio of the synergist is 1-3: 2-4 of alkyl glycoside and isomeric alcohol polyoxyethylene ether;

the solvent is selected from one or more of ethanol, alcohol ether environment-friendly solvent, n-butyl alcohol, ethyl acetate, sec-butyl acetate and dimethyl sulfoxide;

the surfactant is one or a composition of more than two of castor oil polyoxyethylene ether, fatty amine polyoxyethylene ether, calcium alkyl benzene sulfonate, nonionic ethylene oxide block copolymer and alkylphenol formaldehyde resin polyoxyethylene ether;

the antifreezing agent is selected from one or more of glycerol, propylene glycol and polyethylene glycol;

the stabilizer is selected from one or more of tert-butyl hydroquinone, dibutyl hydroxy toluene and epoxy chloropropane;

the water is selected from tap water, distilled water or deionized water;

the preparation method of the microemulsion comprises the following steps: