RU2205540C1 - Wetting agent for pesticides - Google Patents

Abstract

FIELD: pesticides, agriculture. SUBSTANCE: invention relates to agents designated for enhancement of pesticides effectiveness. Wetting agent comprises oxyethylated C₆-C₁₂- saturated alcohols containing 4-10 ethoxy-groups and C₂-C₁₂-saturated alcohols. Wetting agent comprises also polyglycol with molecular mass less 2000 Da and water in the following ratio of components, wt. -%: oxyethylated primary C₆-C₁₂-saturated alcohols containing 4-10 ethoxy- -groups, 20-99; C₂-C₁₂-saturated alcohols, 0.2-3.5; polyglycol with molecular mass less 2000 Da, 0.8-5.0; water, up to 100. Invention allows to reduce consumption norms of surface-active substance in treatment of weakly wettable plants or seeds with pesticides. EFFECT: reduced consumption of substance. 3 cl, 6 tbl

Description

 The invention relates to means intended to increase the biological effectiveness of pesticides, which are used to protect cultivated plants from weeds (herbicides), diseases (fungicides and seed dressers), harmful insects (insecticides). A wetting agent can also be used to increase the biological effectiveness of plant growth regulators that process vegetative plants or seeds.

 Pesticides (herbicides, fungicides, seed disinfectants, insecticides), as well as plant growth regulators, are produced in the form of complex formulations (hereinafter preparations) that contain biologically active substances (active substances), excipients and inert fillers or solvents.

 Before use, working solutions (suspensions, emulsions) are prepared from preparations by mixing with water, which are treated with vegetative plants or seeds.

 The main auxiliary substance of the preparations is a surfactant. It ensures uniformity and stability of both the preparation itself and the working solution (emulsion, suspension) of the preparation in water, as a result of which the biological effectiveness of the pesticide is increased.

Known herbicidal composition based on N-phosphonomethylglycine and 2,4-dichlorophenylacetic acid containing amine salts of alkyl sulfonates and alkylnaphthalene sulfonates (AS USSR 1665561, MKI ⁶ A 01 N 25/22, publ. 20.10.95) as a surfactant. It is noted that by reducing surface tension, auxiliary additives increase the biological activity of the herbicidal composition by 10-15%.

Describes herbicidal compositions based on N-fosfonmetilglitsina containing as adjuvants mixture of polypropylene glycol having a molecular weight of 300-10000 and a compound of [R ¹ R ² R ^{3 _{N (OA) n -H] +}} X - in the ratio of 1: 40-1: 2 (US patent 5430005, MKI ⁶ A 01 N 25/30, publ. 04.07.95).

Known preparative form of glyphosate containing surfactants with a chemical structure R ₁ - (OR ₂ ) mN [(R ₃ -O) _x -H] ₂ (RF application 97118427/04, MKI ⁶ A 01 N 57/20, publ. 15.03. 96).

A known herbicidal composition based on chlorosulfuron and its analogues, in which a mixture of polyethylene glycol ethers and fatty alcohols and anionic substances (sodium salts of sulfosuccinic acid, polyvinyl alcohol, polyacrylic acid) is used as a surfactant (AS USSR 1269296, MKI ⁶ A 01 N 25/00, publ. 10.03.97).

Glyphosate-based pesticidal compositions containing polyoxyalkylenealkylamine surfactants Me (CH ₂ ) _x - N [(R ¹ O) _n H] - (R ² O) _m H with mild irritant effect on the eyes are proposed (US Pat. No. 6,063,733, MKI ⁷ A 01 N 57/02, publ. 05.16.2000).

Known auxiliary substance containing 88% fatty acids of rape oil and 12% polyethoxylated nonylphenol, which provides high adhesion of the pesticide solution to plants. When it is added in an amount of 0.1 kg per 20 l of atrazine, the consumption rate of atrazine herbicide is reduced by 40-50% (Polish patent 168374, MKI ⁶ A 01 N 25/29, publ. 02.29.96).

A combination of alkanolamide surfactants of the structure R ¹ CONR ² R ³ with the ability to distribute and adhere to surfaces is described (US patent 5906961, MKI ⁷ A 01 N 25/02, publ. 25.05.99).

 Known surfactants are either anionic or cationic substances. The active substances of many pesticides are organic acids or bases, therefore, such surfactants are specific and are usually used only with the corresponding groups of pesticides.

Non-ionic surfactants are more universal. These include, in particular, an additive to pesticidal compositions, which is ethylene oxide / propylene oxide block copolymers with a total molecular weight of from 2200 to 15000, which is the closest in properties to the invention (application 98103865/04, Russia, MKI ⁶ A 01 N 25/30, publ. 02.26.98).

 The main disadvantage of high molecular weight block copolymers is the need to use an increased consumption rate to ensure uniform wetting of the pesticide with leaves of plants or seeds with a working solution, in particular with a wax coating (dense cuticle) or thick pubescence (fluffy layer).

 The problem to which the invention is directed is to reduce the consumption rate of a surfactant when pesticides are treated with poorly wettable plants or seeds, as well as expanding the raw material base to obtain wetting agents used in pesticidal compositions.

This problem is solved in that the wetting agent for pesticides based on a nonionic surfactant contains C ₆ -C ₁₂ ethoxylated primary fatty alcohols containing 4-10 ethoxyl groups, C ₂ -C ₁₂ fatty alcohols, polyglycol with a molecular weight of less than 2000 and water , wt.%:
Ethoxylated primary fatty alcohols - 20-99
C ₆ -C ₁₂ containing 4-10 ethoxyl groups
Fatty alcohols C ₂ -C ₁₂ - 0.2-3.5
Polyglycol with a molecular weight of less than 2000 - 0.8-5.0
Water - Up to 100
The wetting agent may also optionally contain urea in an amount of from 0 to 6.0 wt.% And ethoxylated monoalkylphenols based on propylene oligomers in an amount of from 0 to 7.0 wt. %

The wetting agent is obtained by simple mixing at a temperature of 10-30 ^o C of ethoxylated C ₆ -C ₁₂ primary fatty alcohols containing 4-10 ethoxyl groups and water, followed by the introduction of other components with stirring until a homogeneous solution is obtained.

The wetting agent can be introduced into the composition of liquid pesticides at the stage of their production (formulation) or added to the working solution of the pesticide immediately before use in the following quantities:
- when processing vegetating plants with a consumption rate of 0.05-0.50 l per 1 hectare of cultivated area;
- when processing seeds with a consumption rate of 0.01-1.0 liters per 1 ton of seeds.

 Table 1 presents options for tested wetting compositions.

The tested compositions 1-4 differ mainly in the concentration of the main surfactant in them, namely the ethoxylated C ₆ -C ₁₂ primary fatty alcohols containing 4-10 ethoxyl groups, which increases from 25 to 99%. Moreover, in compositions 1-4, the concentration of water decreases simultaneously from 64 to complete absence.

 For comparison, tests were also carried out with ethylene oxide / propylene oxide block copolymer, which is included in the composition of the herbicide acifluorfen.

 The wetting ability of the aqueous solutions of the compositions was determined by applying 0.02 ml of solution drops from a glass pipette onto pieces of freshly cut leaves of characteristic plants and then measuring the average diameter of the resulting drops.

θ<90
где V - объем жидкости в сегменте, мм³;
D - видимый диаметр капли на поверхности, мм;
θ - краевой угол смачивания.With a small solution volume, the droplets formed on a solid surface can be considered as segments of a ball. Simple transformations of the well-known formula for calculating the volume of a segment of a ball show that its geometric parameters are interconnected by the equation

θ <90
where V is the volume of fluid in the segment, mm ³ ;
D is the apparent diameter of the droplet on the surface, mm;
θ is the wetting angle.

 A decrease in the wetting angle θ causes an increase in the apparent diameter of the liquid drop of a given volume, which indicates an increase in the wetting ability of the liquid.

Measurements show that:
- the leaves of plants are not equally wetted by both pure water and solutions of different compositions;
- at a certain concentration of the wetting agent, a drop of liquid spreads over the surface of the plant leaf in the form of a wet spot (in table 2, the diameter of such drops is indicated> 15, since the wetted surface has a complex configuration);
- tested compositions 1-4 in comparison with ethylene oxide / propylene oxide block copolymer have a higher wetting ability.

 Table 2 presents comparative data on the effect of the concentration of wetting agent (composition 1-4) and the prototype on the diameter of a drop of an aqueous solution on the surface of plant leaves.

 The necessary dosage of the wetting agent when processing vegetating plants is determined by experiments in which the biological effectiveness of pesticides was studied. Table 3 shows data on the reduction in the number of weeds in winter wheat crops when they are treated with Cowboy herbicide with a herbicide consumption rate of 0.15 l / ha, with a working fluid consumption of 250 l / ha.

These experiments show that:
- when the wetting dose is less than 0.05 l / ha, its presence in the preparation or directly in the working solution does not affect the biological effectiveness of the herbicide;
- with increasing dose of the wetting agent from 0.05 to 0.50 l / ha, the biological effectiveness of the herbicide increases;
- an increase in the dose of the wetting agent in excess of 0.50 l / ha does not affect the biological effectiveness of the herbicide.

 Close data were obtained when testing the wetting agent with other herbicides, as well as fungicides, insecticides and plant growth regulators. Selected data are given in table 4.

 The necessary dosage of the wetting agent when processing plant seeds was determined in laboratory experiments in which seeds of different cultures were treated with the plant growth regulator Immunocytophyte (hereinafter referred to as “IMC”) in accordance with the approved regulations for its use (State Catalog of Pesticides and Agrochemicals Permitted for Use in the Russian Federation) Federation in 2001., M.,: State Commission on Chemical Pest Control, Plant Diseases, Weeds and Biologically Active Substances, 2001). The uniformity of wetting of the seeds with a working solution that contained a dye was visually evaluated by the uniformity of the coloring of the seeds.

 The experiments showed that to ensure uniform wetting of large smooth seeds of plants, the required dose is 0.01-0.10 l / ha, and for wetting small seeds - 0.1-1.0 l / t. This difference is due to the need to use in the processing of small seeds of a very large volume of working fluid. Table 5 presents data on the effect of the dosage of the wetting agent (composition 1) on the uniformity of wetting of seeds with the working solution of the plant growth regulator "IMC": (-) - incomplete wetting, (+) - complete wetting.

 Data on the influence of the wetting agent additive in the working solution on the biological effectiveness of the Baytan universal dressing agent and the IMC plant growth regulator when treating winter wheat seeds are presented in table 6.

 Experiments show that the addition of a wetting agent in an amount of 0.04 l / t in conjunction with the KOS film former when treating winter wheat seeds with both a dressing agent and a plant growth regulator significantly increases their biological effectiveness.

Claims (2)

1. Wetting agent for pesticides based on a nonionic surfactant, characterized in that it contains C ₆ -C ₁₂ ethoxylated primary fatty alcohols containing 4-10 ethoxyl groups, C ₂ -C ₁₂ fatty alcohols, polyglycol with a molecular weight of less than 2000 and water, wt.%:
Ethoxylated primary fatty alcohols C ₆ -C ₁₂ containing 4-10 ethoxyl groups - 20-99
Fatty alcohols C ₂ -C ₁₂ - 0.2-3.5
Polyglycol with a molecular weight of less than 2000 - 0.8-5.0
Water - Up to 100
2. A wetting agent according to claim 1, characterized in that it further comprises urea in an amount of from 0 to 6.0 wt.%.  3. Wetting agent according to any one of claims 1 or 2, characterized in that it further comprises ethoxylated monoalkylphenols based on propylene oligomers in an amount of from 0 to 7.0 wt.%.

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