CN110839638B

CN110839638B - Microemulsion containing difenoconazole and propiconazole and preparation method thereof

Info

Publication number: CN110839638B
Application number: CN201910969779.0A
Authority: CN
Inventors: 王爱臣; 吴丽文; 夏姗姗; 莫俊锐; 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: 2020-12-15
Anticipated expiration: 2039-10-12
Also published as: CN110839638A

Abstract

The embodiment of the invention discloses a microemulsion containing difenoconazole and propiconazole, belonging to the technical field of pesticides. The microemulsion containing the difenoconazole and the propiconazole comprises the following components in percentage by mass: 10-20% of difenoconazole, 10-20% of propiconazole, 10-25% of surfactant, 20-30% of solvent, 1-5% of synergist and 2-5% of antifreezing agent, and the mixture is supplemented to 100% by water, wherein the surfactant is prepared from the following components in parts by weight of 3-6: 2-3: 2-3 of triphenylethyl phenol polyoxyethylene ether, polyoxyethylene ether nonionic and bisamide disulfonic acid sodium salt. 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 containing difenoconazole and propiconazole and preparation method thereof

Technical Field

The embodiment of the invention relates to the technical field of pesticides, and particularly relates to a microemulsion containing difenoconazole and propiconazole and a preparation method thereof.

Background

The difenoconazole triazole fungicide has systemic property, is a sterol demethylation inhibitor, has wide bactericidal spectrum, can improve the yield and guarantee the quality of crops by leaf surface treatment or seed treatment, and has lasting protection and treatment activity on the subphylum loachirima, the subphylum basidiomycotina and the fungi imperfecti, powdery mildew, rust fungi and certain species-borne pathogenic bacteria including alternaria, ascochyta, urospora, colletotrichum, gloeophyta and other fungi.

Propiconazole belongs to triazole bactericides in sterol inhibitors, has the action mechanism of influencing the biosynthesis of sterol, destroying the cell membrane function of pathogenic bacteria and finally causing cell death, thereby playing the roles of sterilization, disease prevention and treatment, is a systemic bactericide with the functions of protection and treatment, can be absorbed by roots, stems and leaves and can be quickly conducted upwards in plants, and can prevent and treat diseases caused by ascomycetes, basidiomycetes and imperfect fungi, particularly has better prevention and treatment effects on rot, powdery mildew and bakanae disease of rice.

The microemulsion consists of pesticide raw materials, surfactant, water, stabilizer and other auxiliary agents, and belongs to a thermodynamic stable dispersion system. It is characterized in that water is used as a medium, and no or little organic solvent is contained, so the water-based fuel oil is non-combustible and non-explosive, the production operation, storage and transportation are safe, the environmental pollution is little, and a large amount of organic solvent is saved; the pesticide has extremely high dispersity to reach the micronization degree, the pesticide particles are generally only 0.1-0.01 micron, and the appearance is similar to that of a transparent or slightly transparent liquid; good dispersibility in water, strong permeability and good adhesive force to a target body, and low requirement on equipment. Therefore, microemulsions are very promising pesticide formulations.

After the difenoconazole and the propiconazole are compounded into the microemulsion for use, on one hand, the drug resistance of pathogenic bacteria is greatly slowed down, on the other hand, the bactericidal spectrum of each single dose is further widened, the dosage is reduced, and the compound difenoconazole microemulsion has positive significance for protecting ecology and environment.

The advantages and disadvantages of pesticide formulations are closely related to the activity of pesticides and the selection of auxiliary agents, the molecular structures and the physicochemical properties of various pesticide raw materials are far different, and the auxiliary agents including surfactants and the like selected for preparing the pesticide formulations are often different in order to ensure that the pesticide formulations have excellent stability and biological activity. Chinese patent application CN 102057923a discloses a bactericidal composition with difenoconazole and propiconazole as active components, wherein the microemulsion of the bactericidal composition comprises difenoconazole, propiconazole, an emulsifier, a cosolvent, a stabilizer, a synergist, an antifreeze and purified water, only the stability of the microemulsion is increased, but no experimental data on stability is provided, and the used solvent is cyclohexanone, which has great toxicity to human body and causes pollution to 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 containing the difenoconazole and the propiconazole 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 embodiments of the present invention, there is provided a microemulsion containing difenoconazole and propiconazole, which comprises the following components in percentage by mass: 10-20% of difenoconazole, 10-20% of propiconazole, 20-30% of solvent, 10-25% of surfactant, 1-5% of synergist and 2-5% of antifreezing agent, and the mixture is supplemented to 100% by water, wherein the surfactant is prepared from the following components in parts by weight of 3-6: 2-3: 2-3 of triphenylethyl phenol polyoxyethylene ether, polyoxyethylene ether nonionic and bisamide disulfonic acid sodium salt.

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

Further, the synergist is selected from one or more of siloxane modified polyether, alkyl succinamide sulfonate and high-efficiency fluorine-containing wetting penetrant.

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

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

According to a second aspect of embodiments of the present invention, there is provided a method of preparing a microemulsion containing difenoconazole and propiconazole as described above, the method comprising the steps of:

dissolving difenoconazole and propiconazole by using a solvent, stirring after the difenoconazole and the propiconazole are fully dissolved, adding a surfactant, a synergist and an antifreezing agent during stirring, slowly adding water into the mixed solution after uniformly mixing, and fully stirring to obtain the microemulsion containing the difenoconazole and the propiconazole.

The embodiment of the invention has the following advantages:

1. according to the invention, the difenoconazole and the propiconazole are used as active ingredients, so that the stability and the biological activity of the dosage form are not influenced by the added auxiliary agents, the types of the surfactant, the synergist, the antifreezing agent and the solvent are screened and optimized in compounding, the prepared microemulsion emulsion is qualified in stability, heat storage stability and low temperature stability, and the transparent temperature range is wide.

2. The invention screens the surfactant, the surface tension (diluted by 2000 times) of the preparation is less than or equal to 37mN/m, the penetration time (canvas method, diluted by 500 times) is less than 30min, the utilization rate of the preparation in use is improved, and the drug effect is improved.

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 containing difenoconazole and propiconazole of this example comprises:

20kg of difenoconazole and 10kg of propiconazole;

15kg of isopropanol and 5kg of dimethyl sulfoxide;

10kg of triphenylethyl phenol polyoxyethylene ether, 4kg of polyoxyethylene ether nonionic and 6kg of bisamide disulfonic acid sodium;

1kg of siloxane modified polyether;

5kg of glycerol;

tap water was added to 100 kg.

The preparation method comprises the following steps:

dissolving difenoconazole and propiconazole by using a solvent (isopropanol and dimethyl sulfoxide), stirring after the difenoconazole and the propiconazole are fully dissolved, adding a surfactant (phenethylphenol polyoxyethylene ether, polyoxyethylene ether nonionic and bisamide disulfonic acid disodium), a synergist (siloxane modified polyether) and an antifreezing agent (glycerol) during stirring, slowly adding water (tap water) into the mixed solution after uniformly mixing, and fully stirring to obtain the microemulsion containing the difenoconazole and the propiconazole.

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

Example 2

10kg of difenoconazole and 20kg of propiconazole;

30kg of alcohol ether environment-friendly solvent;

10kg of triphenylethyl phenol polyoxyethylene ether, 6kg of polyoxyethylene ether nonionic and 5kg of bisamide disulfonic acid sodium;

3kg of efficient fluorine-containing wetting penetrant;

4kg of polyethylene glycol;

distilled water was added to 100 kg.

Example 3

15kg of difenoconazole and 15kg of propiconazole;

20kg of alcohol ether environment-friendly solvent and 5kg of isopropanol;

12kg of triphenylethyl phenol polyoxyethylene ether, 6kg of polyoxyethylene ether nonionic and 5kg of bisamide disulfonic acid sodium;

2kg of alkyl succinamide sulfonate and 2kg of siloxane modified polyether;

5kg of propylene glycol;

tap water was added to 100 kg.

Example 4

10kg of difenoconazole and 10kg of propiconazole;

18kg of isopropanol and 6kg of ethyl acetate;

6kg of triphenylethyl phenol polyoxyethylene ether, 2kg of polyoxyethylene ether nonionic and 2kg of bisamide disulfonic acid sodium;

5kg of alkyl succinamide sulfonate;

1kg of propylene glycol and 1kg of polyethylene glycol;

tap water was added to 100 kg.

Example 5

15kg of difenoconazole and 15kg of propiconazole;

20kg of sec-butyl acetate and 5kg of isopropanol;

6kg of triphenylethyl phenol polyoxyethylene ether, 3kg of polyoxyethylene ether nonionic and 3kg of bisamide disulfonic acid sodium;

3kg of efficient fluorine-containing wetting penetrant and 2kg of siloxane modified polyether;

3kg of glycerol and 2kg of polyethylene glycol;

deionized water was added to 100 kg.

Comparative example 1

This comparative example differs from example 3 only in the surfactant used, which: 18kg of triphenylethyl phenol polyoxyethylene ether and 6kg of polyoxyethylene ether nonionic.

Comparative example 2

This comparative example differs from example 3 only in the surfactant used, which: 12kg of polyoxyethylene ether nonionic and 12kg of bisamide disulfonic acid sodium.

Comparative example 3

This comparative example differs from example 3 only in the surfactant used, which: 15kg of triphenylethyl phenol polyoxyethylene ether and 9kg of bisamide disulfonic acid sodium.

Comparative example 4

This comparative example differs from example 3 only in the synergist used, which was 4kg of fatty alcohol polyoxyethylene ether.

Test example 1

Stability test of microemulsion

Emulsion stability test: the method is carried out according to GB/T1603-2001. Adding 100mL of standard hard water with the temperature of 30 +/-2 ℃ into a 250mL beaker, sucking 0.5mL of sample by using a pipette, and slowly adding the sample into the hard water (diluted by 200 times) under the condition of continuously stirring to prepare 100mL of emulsion; stirring at the speed of 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 ℃; 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 decomposition rates of the difenoconazole and the propiconazole by using 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 1-5 and comparative examples 1-4 of the present invention 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 5 are all qualified, and the transparent temperature range is wider than that of other comparative examples, which illustrates the stable performance of the microemulsion of the examples of the present invention, further, when comparing example 3 with comparative examples 1 to 4, the heat storage decomposition rates of difenoconazole and propiconazole of example 3 are both significantly lower than those of comparative examples 1 to 4, and the transparent temperature range is also wider than that of other comparative examples, which illustrates that the synergists and surfactants of the examples of the present invention have important significance for the heat storage stability and the wide transparent temperature range of the microemulsion.

Physical and chemical property measurement of microemulsion

The samples were diluted 2000-fold, respectively, and their surface tensions were measured by a platinum plate method using an a101 surface tension meter.

Penetration time: by referring to HG/T2575-.

The microemulsions of examples 1-5 of the present invention and comparative examples 1-4 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	36.12	28
Example 2	36.84	25
			Example 3	32.29	19
Example 4	33.89	28
			Example 5	33.01	26
Comparative example 1	38.98	34
			Comparative example 2	37.15	32
Comparative example 3	40.21	40
			Comparative example 4	38.26	35

As can be seen from Table 2, the samples of examples 1-5 having lower surface tension values than those of comparative examples 1-3 and having shorter penetration times than those of comparative examples 1-3 demonstrate the synergistic effect between the surfactant components of the examples of the present invention, which significantly reduces the surface tension of the drug solution, thereby reducing the penetration times. The samples of examples 1-5 had lower surface tension values than comparative example 4 and less penetration times than comparative example 4, indicating that the component synergists also have an effect on the performance of the microemulsion. The microemulsion of the embodiment of the invention has good wetting capacity, increases the spreading, penetration and other capacities on the surface of the liquid medicine, and improves the utilization rate of the liquid medicine, thereby improving the control effect.

Test example 2

Field control effect test of rice sheath blight disease

The microemulsion of examples 1 to 5 was used as a test agent, the microemulsion of comparative examples 1 to 4 and a commercial product of 30% difenoconazole-propiconazole emulsifiable concentrate were used as a control agent, the application dose and the application dose are shown in table 3, and a clear water blank was used as a control to conduct a control effect test, wherein 11 treatments were performed in total, 3 repetitions were performed, 33 cells were performed in total, and the area of each cell was 20m²The cells are arranged in random blocks.

TABLE 3

Numbering	Medicament	Active ingredient (g/hectare)	Dosage of the preparation (g/mu)
				1	Example 1	90	20
2	Example 2	90	20
				3	Example 3	90	20
4	Example 4	90	30
				5	Example 5	90	20
6	Comparative example 1	90	20
				7	Comparative example 2	90	20
8	Comparative example 3	90	20
				9	Comparative example 4	90	20
10	Commercially available product	90	20
				11	Blank control (clear water)	--

The application method comprises the following steps: the first application is carried out at the early stage of the rice sheath blight disease, the next application is carried out every 10 days, and the application is carried out 3 times in the whole period.

The investigation method is a diagonal five-point sampling method, 5 groups of rice are connected in each point investigation, 25 groups of rice are investigated in each cell, and the total number of investigated plants and the number of diseased plants at each level are recorded respectively.

Sheath blight grading standard:

level 0: the whole plant has no diseased leaves;

level 1: the fourth leaf and the following leaf sheaths thereof, the leaf is diseased (the sword leaf is taken as the first leaf);

and 3, level: the third leaf and the leaf sheaths below the third leaf cause diseases;

and 5, stage: the second leaf and the leaf sheaths below the second leaf cause diseases;

and 7, stage: the scab leaves and the leaf sheaths below the scab leaves are attacked;

and 9, stage: the whole plant is attacked and withered in advance.

The disease index and the prevention and treatment effect are calculated according to the following formula:

disease index (%) ═ Σ (number of diseased leaves at each stage × number of relative stage)/(total number of examined leaves × 9) × 100

Control effect (%) - (1- (CK)₀×PT₁)/(CK₁×PT₀)]×100

In the formula: CK (CK)₀-pre-drug disease index in placebo zone;

CK₁-disease index after drug administration in placebo zone;

PT₀-pre-dose disease index in the agent treatment area;

PT₁-disease index after drug treatment area application.

After the pesticide is applied, the rice in the application area grows normally, abnormal phenomena such as growth of rice leaves, heading and flowering, grouting and fructification and the like are not found, and the pesticide damage symptom is not shown, so that the microemulsion is safe to the rice in the test dose range.

The disease index and the results of the prevention and treatment effects are shown in Table 4

TABLE 4

As can be seen from table 4, after the application for the 1 st time, the control effect range of the microemulsion of the embodiment of the present invention on the rice sheath blight disease is 70.46-76.83%, which is higher than the control effect of the comparative example and the commercially available products, after the application for the 2 nd time, the control effect range of the microemulsion of the embodiment of the present invention on the rice sheath blight disease is 81.28-87.60%, which is higher than the control effect of the comparative example and the commercially available products, and after the application for the 3 rd time, the control effect range of the microemulsion of the embodiment of the present invention on the rice sheath blight disease is 92.71-95.04%, which is higher than the control effect of the comparative example and the commercially available products, wherein the microemulsion of the embodiment 3 has the most excellent control effect at each time, which indicates that the collocation of the components is more reasonable and the compounding effect is.

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 containing the difenoconazole and the propiconazole is characterized by comprising the following components in percentage by mass: 10-20% of difenoconazole, 10-20% of propiconazole, 20-30% of solvent, 10-25% of surfactant, 1-5% of synergist, 2-5% of antifreezing agent, supplementing to 100% with water,

wherein the surfactant is prepared from the following components in a weight ratio of 3-6: 2-3: 2-3 of triphenylethyl phenol polyoxyethylene ether, polyoxyethylene ether nonionic and bisamide disulfonic acid sodium;

the solvent is selected from one or more of alcohol ether environment-friendly solvents, isopropanol, ethyl acetate and sec-butyl acetate;

the synergist is selected from one or more of siloxane modified polyether, alkyl succinamide sulfonate and high-efficiency fluorine-containing wetting penetrant;

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

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

2. A method for preparing a microemulsion of difenoconazole and propiconazole according to claim 1, which comprises the following steps: