CN112868649A

CN112868649A - Emulsifiable weeding composition

Info

Publication number: CN112868649A
Application number: CN202110185053.5A
Authority: CN
Inventors: 罗昌炎; 詹姆斯·T·布里斯托
Original assignee: Jiangsu Rotam Chemical Co Ltd
Current assignee: Jiangsu Rotam Chemical Co Ltd
Priority date: 2021-02-10
Filing date: 2021-02-10
Publication date: 2021-06-01
Anticipated expiration: 2041-02-10
Also published as: CN112868649B

Abstract

The present invention provides an emulsifiable herbicidal composition comprising at least one polyether-polysiloxane and one dinitroaniline herbicidal active. The polyether-polysiloxane significantly reduces the wall build-up and adherence of the dinitroaniline emulsifiable composition, thereby reducing the ability of the dinitroaniline active to stain the skin of manufacturing equipment and spray equipment as well as the clothing of the applicator.

Description

Emulsifiable weeding composition

Technical Field

The present invention relates to an emulsifiable herbicidal composition, and more particularly to an emulsifiable herbicidal composition comprising at least one dinitroaniline herbicidal active which reduces or reduces the coloring power of the dinitroaniline herbicidal active on equipment and clothing skin.

Background

Dinitroaniline herbicides have developed faster since their discovery in 1953, mainly because dinitroaniline herbicides have a broad herbicidal spectrum and can control not only annual grassy weeds but also some annual broadleaf weeds. All dinitroaniline herbicide varieties are soil treatment agents, mainly for controlling weed sprouts, and are therefore frequently applied before or after seeding of crops. The weeding composition has stable weeding effect, can also play a good weeding effect under the drought condition, is a characteristic which other herbicides do not have, and is very beneficial to areas with general drought phenomena. The dinitroaniline herbicide has medium or slightly long lasting period in soil, half life of most varieties of 2-3 months, and no residual toxicity to most of afterculture crops in rotation when the dinitroaniline herbicide is used correctly. In addition, most dinitroaniline herbicides have low water solubility and are strongly adsorbed, so that the dinitroaniline herbicides do not move vertically or transversely in soil, are difficult to move downwards under the condition of high soil water content, do not pollute underground water sources, and do not accumulate in soil after repeated application. Therefore, the dinitroaniline herbicide is widely used on crops such as cotton, soybean, corn and the like, and has large demand and large dosage.

Pendimethalin (pendimethalin), a typical product of dinitroaniline herbicides, is a selective preemergence and postemergence dry field soil treatment herbicide with the chemical name of N- (1-ethyl propyl) -2, 6-dinitro-3, 4-dimethylaniline. The herbicide can be absorbed by sprouts of emerging weeds, so that the herbicide is combined with tubulin after entering a plant body, thereby inhibiting mitosis of plant cells and causing death of the weeds, and the herbicide is widely applied to various crops such as corn, soybean, peanut, cotton, direct seeding upland rice, potato, tobacco, vegetables and the like, and can effectively prevent and treat annual gramineous weeds and part of broadleaf weeds, such as nutgrass flatsedge, cockspur grass, crabgrass, green bristlegrass, moleplant seeds, eleusine indica, purslane, amaranthus, chingma abutilon, black nightshade, cyperus esculentus, cyperus heterophyllus and the like.

However, because dinitroaniline herbicides are all yellow-colored crystalline solids, the resulting emulsifiable concentrate products also exhibit a strong yellow color. These products are very coloring and are also easily absorbed, resulting in equipment, plants and packaging lines producing the emulsifiable concentrate products often being colored yellow or yellowish and difficult to clean. To avoid cross-contamination, especially removal of yellow color, manufacturers must use large amounts of clear water or even organic solvents to soak for complete removal. This is time consuming and laborious and produces large amounts of waste water containing organic solvents, increasing the cost of waste water post-treatment, which is undesirable for the producer. However, as an applicator, it is also relatively difficult to clean the spraying equipment after spraying the aqueous spray containing the dinitroaniline herbicide. Especially spray solutions that inadvertently drip onto clothing or skin, causing yellowing of the coloration of the clothing or skin, are also difficult to clean, which is undesirable for the applicator.

Another US6669949B2 discloses a method of improving the spreading of an oil composition. The method comprises adding at least one asymmetrically substituted polysiloxane. The polysiloxane is added to enable the oil dispersion composition (oil suspending agent) to spread on the plant leaf surface, so as to achieve the effect of improving the pesticide effect. However, it has been found that the presence of polysiloxanes can easily lead to poor dilution stability of the emulsifiable composition, e.g. the upper layer of the dilution can easily cause quality problems such as oil slick, creaming and the like

Accordingly, it would be desirable to provide a stable quality emulsifiable formulation which reduces or reduces the wall build-up and/or adherence of the dinitroaniline herbicidal active and which is easy to clean.

Disclosure of Invention

To solve the above technical problem, in a first aspect, the present invention provides an emulsifiable herbicidal composition comprising a polyether-polysiloxane, and a dinitroaniline herbicidal active, preferably a modified polyether-polysiloxane. Preferably, the emulsifiable herbicidal composition further comprises an aromatic hydrocarbon solvent, one or more other suitable surfactants.

It has been unexpectedly found that the use of polyether-polysiloxanes, particularly modified polyether-polysiloxanes, are particularly suitable for reducing the wall build-up and/or adhesion of dinitroaniline herbicide emulsifiable products for ease of cleaning.

In a preferred embodiment, the present invention provides an emulsifiable herbicidal composition comprising pendimethalin as an active ingredient, and a polyether-polysiloxane; preferably, the emulsifiable herbicidal composition further comprises an aromatic hydrocarbon solvent and one or more other suitable surfactants.

In a further aspect, the present invention provides the use of a polyether-polysiloxane, in particular a modified polyether-polysiloxane, in an emulsifiable composition of at least one herbicidal dinitroaniline active for reducing the wall build-up and/or adhesion of the dinitroaniline active emulsifiable composition for easy cleaning. The dinitroaniline active matter is preferably pendimethalin, dimethomorph, butralin and trifluralin.

In another aspect, the present invention provides an emulsifiable herbicidal composition comprising:

(a) 10-50% by weight of at least one dinitroaniline herbicidal active;

(b) 0.1-10% by weight of a polyether-polysiloxane;

(c) 40% to 80% by weight of an aromatic hydrocarbon solvent;

(d) 0.1-10% by weight of a co-solvent;

(e) 3-15% by weight of a surfactant.

Wherein the herbicidal dinitroaniline active is selected from the group consisting of: pendimethalin, dimethomorph, butralin and trifluralin.

As mentioned above, it has been found that the compositions of the present invention significantly reduce the wall build-up and/or adhesion capabilities of the dinitroaniline emulsifiable formulation compared to compositions of the prior art; effectively reduces the coloring capability of the dinitroaniline on production equipment, spraying instruments and the skin of clothes of a user, and achieves the effect of convenient cleaning. In addition, the dilution stability of the composition diluted by adding water also meets the industrial standard, the phenomena of floating oil and milk fat are not generated, and the composition has better dilution stability.

Thus, in a further aspect, the present invention provides the use of a polyether-polysiloxane for reducing the wall build-up and/or adherence of a dinitroaniline herbicidal active emulsifiable formulation, greatly improving cleaning.

The compositions of the present invention are emulsifiable concentrate formulations and comprise one or more herbicidally active dinitroanilines as active ingredient. Suitable herbicidally active dinitroanilines for use in the compositions of the present invention are known in the art and are commercially available.

Preferred dinitroaniline actives for use in the present invention are pendimethalin, dimethomole, butralin, trifluralin. The composition may comprise a single dinitroaniline active. Alternatively, the composition may comprise two or more dinitroaniline actives. The composition may also comprise other active ingredients in combination with the dinitroaniline, if desired. Suitable other active ingredients for use in combination with the dinitroaniline actives are known in the art and are commercially available.

The dinitroaniline active may be present in the emulsifiable compositions of the present invention in any suitable amount to provide the desired herbicidal activity. Preferably, the dinitroaniline active is present in an amount of about 1% to 60% by weight, such as 1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55% or 60%, more preferably 2% to 55% by weight, still more preferably 5% to 50% by weight, most preferably 10% to 50% by weight.

The emulsifiable composition of the present invention further comprises a polyether-polysiloxane. The polyether-polysiloxane is preferably a modified polyether-polysiloxane. The modified polyether-polysiloxane is preferable because it shows better properties in terms of surface tension, critical micelle concentration, foaming ability, compatibilization property and compatibility. The polyether-polysiloxane copolymer comprises polyether chains linked to polysiloxane chains. The modified polyether-polysiloxane can be classified into Si-O-C type and Si-C type according to the different connections between the polyether segment and the polysiloxane segment. One preferred class of polyether-polysiloxanes is polyether-polysiloxane copolymers.

Suitable polyether-polysiloxanes for use in the present invention are known in the art and are commercially available. For example, modified polyether-polysiloxanes are available under the trade names Breakthrough9902, Breakthrough9903, Breakthrough5503, Breakthrough9907, and Breakthrough9908 (available from Degussa).

The polyether-polysiloxane can be present in the emulsifiable composition of the invention in any suitable amount, particularly in an amount sufficient to provide a reduction in the ability of the emulsifiable composition to wall build-up and/or adhere. Preferably, the polyether-polysiloxane is present in an amount of 0.01% to 15%, for example 0.01%, 0.05%, 0.1%, 1%, 2%, 5%, 8%, 10%, 12%, 12.5%, 13%, 14% or 15%, more preferably 0.05% to 12.5%, particularly preferably 0.1% to 10% by weight of the composition.

The emulsifiable composition of the present invention further comprises a hydrocarbon solvent. Suitable hydrocarbon solvents are aliphatic (e.g. linear or cyclic) or aromatic hydrocarbons. Preferred hydrocarbon solvents are aromatic hydrocarbons. The aromatic hydrocarbon may comprise an aliphatic hydrocarbon substituent in addition to the at least one aromatic hydrocarbon unit. In most cases, the hydrocarbon solvent has a water solubility at 20 ℃ of not more than 5% by weight, preferably not more than 1% by weight, in particular not more than 0.3% by weight. In most cases, the hydrocarbon solvent has a boiling point of at least 100 ℃, preferably at least 150 ℃, especially at least 180 ℃ at 1013 mbar. The hydrocarbon solvent typically contains only carbon and hydrogen atoms. The hydrocarbon solvent is preferably a C6-C20 hydrocarbon, especially a C8-C16 hydrocarbon.

Suitable Aromatic hydrocarbons are in particular all alkyl-substituted Aromatic compounds, such as toluene, xylenes, ethylbenzene and the benzenes having long-chain alkyl groups, for example C9-C10 dialkyl-and trialkyl-benzenes (for example Solvesso 100 from Exxon Mobile Europe or Aromatic 100 from Exxon Mobile USA), C10-C11-alkylbenzenes (for example Solvesso 150 from Exxon Mobile Europe or Aromatic 150 from Exxon Mobile USA) and alkylnaphthalenes (for example Solvesso200 from Exxon Mobile Europe or Aromatic200 from Exxon Mobile USA). Also suitable are mixtures of the abovementioned aromatic compounds. Preferably, the aromatic hydrocarbon comprises no more than 5 wt%, more preferably no more than 2 wt%, especially no more than 1 wt% naphthalene, based on the total weight of the aromatic solvent. Such solvents having a naphthalene content of not more than 1% by weight are commercially available, for example from Exxon Mobile Europe under the name ND (naphthalene lean), for example from Solvesso 150ND and Solvesso200 ND from Exxon Mobile Europe. Even lower naphthalene contents of not more than 0.1 wt.% are present in the products Aromatic 150ULN and Aromatic200ULN available from Exxon Mobile USA.

The aromatic hydrocarbon solvent can be present in any suitable amount. The amount of the aromatic hydrocarbon solvent in the emulsifiable composition of the invention is preferably from about 30% to 90%, for example 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 90%, more preferably from 35% to 85%, and especially preferably from 40% to 80% by weight.

The emulsifiable composition of the present invention further comprises an appropriate amount of a cosolvent including ketone solvents (e.g., cyclohexanone, methyl ethyl ketone, acetone, methyl ethyl ketone), aliphatic alcohol solvents (e.g., methanol, ethanol, propanol, isopropanol, n-butanol, and t-amyl alcohol), ether solvents (e.g., ethyl propyl ether, n-butyl ether, anisole, phenetole, and cyclohexyl methyl ether), ester solvents (e.g., malonic ester, n-butyl acetate, methyl acetate, ethyl acetate, isobutyl acetate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, and propylene carbonate). The existence of the cosolvent greatly improves the stability of the water-blended diluted emulsion of the emulsifiable composition, so that the phenomena of missible oil and milk fat do not occur in the diluted solution for a long time, and the physical stability of the emulsifiable composition is improved. Preferred co-solvents are selected from cyclohexanone, propylene carbonate. The amount of co-solvent in said suitable amount is from 0.5% to 15%, preferably from 1% to 12%, more preferably from 2% to 10% by weight.

The emulsifiable compositions of the present invention also comprise one or more suitable surfactants. Suitable surfactants are those effective in emulsifying the above aromatic solvents in water. Suitable surfactants include anionic surfactants and nonionic surfactants.

Suitable anionic surfactants are alkali metal, alkaline earth metal or ammonium salts of sulfonic acids, sulfuric acids, phosphoric acids, carboxylic acids and mixtures thereof. Examples of sulfonates are alkylarylsulfonates, diphenylsulfonates, alpha-olefin sulfonates, lignosulfonates, sulfonates of fatty acids and oils, sulfonates of ethoxylated alkylphenols, sulfonates of alkoxylated arylphenols, sulfonates of condensed naphthalenes, sulfonates of dodecyl-and tridecylbenzenes, sulfonates of naphthalenes and alkylnaphthalenes, sulfosuccinates or sulfosuccinamates. Examples of sulfates are sulfates of fatty acids and oils, sulfates of ethoxylated alkylphenols, sulfates of alcohols, sulfates of ethoxylated alcohols or sulfates of fatty acid esters. An example of a phosphate is a phosphate ester. Examples of carboxylates are alkyl carboxylates and also carboxylated alcohol or alkylphenol ethoxylates. Preferred anionic surfactants are sulfates and sulfonates.

Suitable nonionic surfactants are alkoxylates, N-substituted fatty acid amides, amine oxides, esters, sugar-based surfactants, polymeric surfactants and mixtures thereof. Examples of alkoxylates are compounds such as alcohols, alkylphenols, amines, amides, arylphenols, fatty acids or fatty acid esters which have been alkoxylated by 1 to 50 equivalents. Ethylene oxide and/or propylene oxide may be used for the alkoxylation, preferably ethylene oxide. Examples of N-substituted fatty acid amides are fatty acid glucamides or fatty acid alkanolamides. Examples of esters are fatty acid esters, glycerol esters or monoglycerides. Examples of sugar-based surfactants are sorbitan, ethoxylated sorbitan, sucrose and glucose esters or alkyl polyglucosides. Examples of polymeric surfactants are homopolymers or copolymers of vinylpyrrolidone, vinyl alcohol or vinyl acetate. Preferred nonionic surfactants are alkoxylates.

The present invention preferably comprises a mixture of two or more surfactants, more preferably a mixture of an anionic surfactant (such as a sulphate or sulphonate) and a nonionic surfactant (such as an alkoxylate).

The one or more surfactants can be present in any suitable amount to provide the desired stability and emulsification effect of the emulsifiable composition. Preferably, the one or more surfactants are present in an amount of at least 1% to 20% by weight, such as 1%, 2%, 5%, 10%, 15% or 20%, more preferably 2% to 18%, particularly preferably 3% to 15%.

Compared with the prior art, the invention has at least the following beneficial effects:

the invention has the advantages that the wall-hanging and/or adhesion capacity of the dinitroaniline is reduced by adopting the emulsified weeding composition prepared by the invention; the coloring capacity of the dinitroaniline on production equipment, spraying equipment and clothes and skin of an applicator is reduced, so that the amount of water for cleaning is greatly reduced, the washing wastewater is reduced, and great convenience and benefits are brought to enterprises and applicators; meanwhile, after the emulsifiable composition is diluted by adding water, the emulsified diluent does not generate floating oil and cream, so that the dilution stability of the dinitroaniline emulsifiable composition is improved, the performance of a preparation is improved, and a satisfactory dinitroaniline emulsifiable composition product is obtained.

Detailed Description

For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Example 7

Example 8

Comparative example 1

Comparative example 2

Comparative example 3

Comparative example 4

Comparative example 5

Comparative example 6

Comparative example 7

Comparative example 8

Elution test

The samples of examples 1-8 and comparative examples 1-8 above were tested for active cleaning efficacy experiments, respectively. The experimental method is as follows: accurately weighing 0.1g of missible oil preparation, dripping the missible oil preparation on white cotton cloth with the side length of 1cm, placing the cotton cloth with the active substance in a flask filled with 100ml of water, carrying out ultrasonic treatment for 5 minutes by using a 50KHZ ultrasonic cleaner, detecting the content of the active substance in the water by using a liquid chromatograph, and finally calculating the elution rate of the active substance. The test was repeated 3 times per experiment, the average was taken and the colour of the cotton after washing was observed at the same time and recorded in table 1 below.

Dilution stability test

The samples of examples 1 to 8 and comparative examples 1 to 8 described above were each tested for dilution stability. The experimental method is as follows: 0.5ml of the sample was pipetted using a pipette and diluted into a conical measuring cylinder (200-fold dilution) containing 99.5ml of water, and after being turned upside down 10 times, the sample was placed in a water bath at 30 ℃ and allowed to stand for half an hour, and each dilution sample was observed, and the results are shown in Table 1 below.

TABLE 1

As can be seen from Table 1, the dinitroaniline emulsifiable concentrate provided by the invention has a one-time elution rate of about 90% and a minimum elution rate of more than 87.55% under the same washing condition, and meanwhile, the color of the washed cotton cloth is remarkably lightened, so that the emulsifiable composition has the characteristic of remarkably reducing the wall hanging and/or adhesion capacity of dinitroaniline products, polluted equipment and clothes can be well cleaned, and the washing water and labor cost are saved. Further demonstrating the property of polyether-polysiloxanes to effectively reduce the wall build-up and/or adhesion capability of the dinitroaniline emulsifiable composition; meanwhile, the emulsifiable composition added with the cosolvent (cyclohexanone and propylene carbonate) has better dilution effect, and the stability of the product is further improved.

Claims

1. An emulsifiable herbicidal composition characterized in that it comprises from 0.1 to 15% by weight of a polyether-polysiloxane and from 5 to 60% by weight of a dinitroaniline herbicidal active and from 1 to 20% by weight of optionally one or more surfactants.

2. The composition as claimed in claim 1, wherein the dinitroaniline herbicidal active is any one or a combination of at least two of pendimethalin, dimethomorph, butralin or trifluralin.

3. The composition of claim 2 wherein the dinitroaniline herbicidal active is pendimethalin.

4. A composition according to any one of claims 1 to 3, characterized in that the dinitroaniline herbicidal active is present in the composition in an amount of from 5 to 50% by weight.

5. Composition according to any one of claims 1 to 3, characterized in that the polyether-polysiloxane is a modified polyether-polysiloxane.

6. Composition according to any one of claims 1 to 3, characterized in that the polyether-polysiloxane is present in the composition in an amount of from 0.1% to 10% by weight.

7. The composition according to any one of claims 1 to 3, characterized in that it further comprises an aromatic hydrocarbon solvent.

8. The composition as claimed in claim 7, wherein the content of aromatic hydrocarbon solvent in the composition is 30 to 90% by weight.

9. The composition according to any one of claims 1 to 3, characterized in that it further comprises one or more surfactants.

10. The composition of claim 9, wherein the composition comprises a nonionic surfactant and an anionic surfactant.

11. The composition of claim 9, wherein the surfactant is present in the composition in an amount of 3% to 15% by weight.

12. An emulsifiable herbicidal composition characterized in that said composition comprises:

(a) 10-50% by weight of at least one dinitroaniline herbicidal active;

(b) 0.1-10% by weight of a polyether-polysiloxane;

(c) 40-80% by weight of an aromatic hydrocarbon solvent;

(d) 0.1-10% by weight of a co-solvent;

(e) 3-15% by weight of a surfactant.

Wherein the dinitroaniline herbicidal active matter is selected from any one or the combination of at least two of pendimethalin, dimethomorph, butralin or trifluralin.

13. Use of a polyether-polysiloxane for reducing the cling ability and/or cling capacity of an emulsifiable composition containing a dinitroaniline herbicidal active, preferably any one or a combination of at least two of pendimethalin, dimethomorph, butralin or trifluralin.