CS262633B1 - Suspension-emulsion combined herbicide and method of its preparation - Google Patents

Abstract

The solution concerns stabilized a combined herbicidal composition in the form of a suspension-emulsion concentrate based on 2-chloro-4-ethylamino-6-isopropylamino- -1,3,5-triazine, 4,6-bis (isopropylamino) - 2-methylthio-1,3,5-triazine and 2-ethyl-6- -methyl-N- (1-methoxy-2-propyl) -chloroacetanilide in wt. a ratio of 6.6 to 10:10 to 5:20 to 30. A herbicidal agent stabilizer is magnesium oxide and / or sulfite powder leachate. A herbicidal composition is prepared by first preparing a 2-chloro- -4-ethylamino-6-isopropylamino-1,3,5- -triazine, surfactant, stabilizer, antifreeze and water, this is homogenizes with silicone defoamer died on colloid mill - at least 85% particles must be smaller or equal 5 µm. Finally, with vigorous stirring add 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) - -chloroacetanilide.

Description

The invention relates to a stabilized combination herbicidal composition in the form of a suspension-emulsion concentrate based on 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, 4,6-bis (isopropylamino) -2-methylthio-1, % Of 3,5-triazine and 2-ethyl-6-methyl-N- (1 H -methoxy-2-propyl) -chloroacetanilide in wt. a ratio of 6.6 to 10:10 to 5:20 to 30. The stabilizer of the herbicidal composition is magnesium oxide and / or a powdered sulphite liquor. The herbicidal composition is prepared by first preparing a mixture of 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, a surfactant, a stabilizer, an antifreeze agent and water, which is homogenized and ground to a colloidal silicone defoamer. At least 85% of the particles must be less than or equal to 5 µm. Finally, 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) -chloroacetanilide was added with vigorous stirring.

The present invention relates to a 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine (atrazine), 4,6-bis (isoporpylamino) -2-methylthio-1-herbicidal combination herbicidal composition. 5-triazine (prometryne) and 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) chloroacetanilide (metolachlor) as well as a process for its preparation.

When using uncombinated atrazine or promethrin or metolachlor based herbicides, the efficacy of these selective herbicides is limited and their successive application to multiple weeds requires successive application, which means practically triple application. Under such conditions, dosing of the active compounds in optimal proportions is not always ensured, in particular if the same application conditions are not observed in individual applications and the possibility of overlapping the spray strips is not prevented.

When used as a tank mix, atrazine-based formulations (e.g., Zeazine 50 DP or Zeazine 40 S, Gesaprim and the like / prometryne) are not always final, for example Gesagard 50 DP,

Prometryn S 50, Prometran 50 WP and the like / and metolachlor (e.g. Dual 500 EC and the like) used in the application spray application, are compatible.

From the physicochemical point of view, it is a colloid-chemically real complex system of suspension (atrazine and prometryne) and emulsion (metolachlor) and these forms can interfere with each other due to system stability.

It has been found that the above-mentioned basic drawbacks are overcome by a suspension-emulsion combination herbicidal composition based on 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine (atrazine), 4,6-bis (isopropylamino) -2 methylthio-1,3,5-triazine (prometryne) and 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) -chloroacetanilide (metolachlor) according to the invention. SUMMARY OF THE INVENTION The suspension-emulsion combination herbicidal composition comprises 6.6 to 10.0 wt. % atrazine, 10.0 to 15.0 wt. % prometryne, 20.0 to 29.0 wt. % of metolachlor, 10.0 to 16.0 wt. % anidnactive and nonionic surfactant, 0.1 to 1.0 wt. % magnesium oxide stabilizer and / or sulfite leach powder, 1.0 to 10.0 wt. % antifreeze based on ethylene glycol and / or propylene glycol, 0.05 to 2.0 wt. silicone antifoam and the rest up to 100% water.

Furthermore, it has been found that in order to prevent the formation of an inverse, highly viscous metolachlor emulsion, it is necessary to prepare a suspension-emulsion combination herbicidal composition according to the invention, characterized in that the mixture of atrazine, prometryne, mixed surfactant, stabilizer and water is homogenized. the mixture is ground on a colloid mill to a particle size of 5 µm. Finally, metolachlor is added and the mixture is homogenized thoroughly.

The composition according to the invention is characterized by a very good and reliable action against both linden-grass and one-year broadleaf weeds. Atrazine and prometryn, compounds of the triazine herbicide family, inhibit photosynthesis and metolachlor inhibits weed germination.

In the process of treating these herbicides as a suspension-emulsion formulation, it has been found that it is absolutely necessary to first prepare the basic reaction mixture by grinding on a colloid mill without metolachlor having the prescribed granulometry / at least 85% by weight. of particles smaller than 5 [mu] m and then supply the required amount of metolachlor for thorough homogenization of the final mixture. This procedure avoided the formation of a V / 0 inverse emulsion in which the discontinuous phase is water and the continuous phase is metolachlor. The presence of this inverse emulsion causes an unbearable high viscosity of the milled reaction mixture, manifested by heating it to a temperature above 40 ° C, a significant deterioration of the colloidal mill effluent and a decrease in physical stability / suspendability / 1% aqueous suspension.

When investigating the shelf life of the finished product, Saley found that prometryn dissolves to a large extent in the metolaohor at temperatures above 40 ° C, from which it exudes in the form of large acicular crystals upon cooling, the presence of which disrupts physically qualitative parameters (impaired flowability and suspendability) .

The physical instability manifested by phase separation (liquid-solid) can be reduced or eliminated by increasing the mixed surfactant content of the final formulation. However, it has been found that by the addition of a magnesium oxide stabilizer and / or a sulfate kraft liquor, said phase separation can be eliminated even at a reduced mixed surfactant content. The following examples illustrate but do not limit the scope of the invention.

Example 1

A homogenized basic reaction mixture of the composition:

9.95% wt. techn. conc. % of atrazine containing 94.6 wt. acc. substances

14.16% wt. Techni. conc. prometryne containing 99.7 wt. acc. substances

14.24% wt. % of a mixed surfactant of 30 wt. % of a dodeoylbenzenesulfonic acid calcium salt and 70 wt. copolymer of ethylene oxide with propylene oxide.

12.94% wt. ethylene glycol

2.59% wt. silicone defoamer

46.12% wt. technological water.

The basic reaction mixture of this composition was ground on a colloidal bead mill until a size of about 85 wt. of all particles equal to or less than 5 µm.

Upon reaching this granulometric composition, for every 100 parts by weight, the weight of " w / w of the basic reaction mixture added 29.42 d. wt. % of technical concentrate of metolachlor containing 96% by weight of metolachlor; acc. substances, the mixture was thoroughly homogenized to obtain a final preparation of the composition:

7.69% wt. techn. conc. % of atrazine containing 94.6 wt. acc. % corresponding to 7.27 wt. atrazine,

10.94% wt. techn. conc. prometryne containing 99.7 wt. acc. substances, which corresponds

10.91% wt. Prometryn.

22.73 »wt. techn. conc. of metolachlor containing 96.0% eq. % corresponding to 21.82 wt. metolachlor,

11.0 wt. % of a mixed surfactant of 30 wt. anionic surfactant + 70 wt. nonionic surfactant,

10.0 wt. ethylene glycol,

2.0 wt. silicone defoamer,

35.64% wt. process water (as a remainder up to 100% w / w).

The final suspension-emulsion combined herbicidal composition thus prepared is prepared according to the invention

7 days of storage at room temperature was phased, about 10% by volume was a solution and 90% by volume mixture of suspension and emulsion.

The fresh and stored product (after shaking homogenization) had very good stability of the dispersion (S) with a prescribed concentration in water of 30 ° N hard, which after 30 minutes sedimentation was 100% (practically non-sedimented).

Example 2

A homogenized reaction mixture, including metolachlor, was fed into a colloidal bead mill of the following composition:

7.69% wt. techn. conc. % of atrazine containing 94.6 wt. acc. substances, i. 7.27% wt. atrazine,

10.94% wt. techn. conc. prometryne containing 99.7 wt. acc. substances, i. 10.91% wt. Prometryn.

22.73% wt. techn. conc. % of metolachlor containing 96 wt. acc. substances i.e. 21,82% metalochlor,

11.0 wt. % of a mixed surfactant of 26 wt. % of a calcium salt surfactant (as in Example 1) and 74 wt. copolymer (as in Example 1),

10.0 wt. ethylene glycol,

0.3 wt. silicone defoamer,

37.34% wt. technological water.

Even after short-term grinding, the viscosity rose sharply as a result of the formation of the V / O emulsion, accompanied by a constantly increasing temperature (above 40 ° C). In the reaction mixture heated as a result of the grinding friction, favorable conditions were created to increase the solubility of prometryne in metolachlor, which, upon cooling, resulted in the formation of large needle-like crystals of prometryne.

Their presence adversely affected the physical parameters of the formulation, which was enormously viscous, had poor flowability and impaired stability of the aqueous dispersion.

Example 3

The product of the following composition was prepared as in Example 1:

7.69% wt. techn. conc. % of atrazine with a content of 94.8 wt. acc. substances

10.94% wt. techn. conc. iprometryn containing 99.7 wt. acc. substances

22.73% wt. techn. conc. % of metolachlor containing 96 wt. acc. substances

11.0 wt. mixed surfactant having the composition as in Example 1

10.0 wt. ethylene glycol

37.66% wt. technological water (as the rest up to 100%)

The freshly prepared product had a dispersion stability of 100%, phased as described in Example 1 when stored at room temperature. The product stored for 14 days at 55 ° C and had a gel-like consistency upon cooling to room temperature. Microscopic examination revealed that it contained a significant amount of needle-like prometryn crystals up to 300 µm in size, which crystallized from the solution in metolachlor. The suspensibility of the stored formulation was 86.9% by weight.

Example 4

Following the procedure of Example 1, a product of the following composition was prepared:

7.69 % wt. techn. conc. Atrazine content of 94.6% wt. acc. substances 10.94 % wt. techn. conc. prometryne containing 99.7 % wt. acc. substances 22,73 % wt. techn. conc. Metolachlor, containing 96 % wt. acc. substances

15.0 wt. mixed surfactant composition as in Example 1

10.0 wt. ethylene glycol

2.0 wt. silicone defoamer

31.64% wt. technological water

The final product obtained was homogeneous and did not phase out even after storage at room temperature for 10 months. It had a 100% yield. Stability against phase separation was achieved by increasing the surfactant from 11 to 15%.

Example 5

The product of the following composition was prepared according to Example 1:

8.03 % wt. techn. conc. % atrazine containing 90.5 wt. acc. substances 10.96 % wt. techn. conc. prometryne containing 99.9 wt. accounting . substances 22.43 % wt. techn. conc. % of metolachlor containing 97.3 wt. acc. substances

13.0 wt. % mixed surfactant of 34 wt. % of a dodecylbenzenesulfonic acid calcium salt and 66 wt. copolymer of ethylene oxide with propylene oxide (as in Example 1)

0.5 wt. powder extract

0.3 wt. silicone defoamer

44.78% wt. technological water

The product had a suspendability of 100% on storage and no phasing occurred. The sample stored for 14 days at a temperature of up to 40 ° C did not differ in particle size from the sample stored at room temperature, after storage the sample was homogeneous (no phase separation), the suspendability was 97.4% by weight. mixed surfactant content of 15 wt. to 13% by weight.

Example 6

The product of the following composition was prepared according to Example 1:

7.67 % wt. techn. conc. Atrazine content of 94.8% wt. acc. substances 10.94 % wt. techn. conc. prometryne containing 99.7 % wt. accounting . substances 22,73 % wt. techn. conc. metolachlor chlorine content 96 % wt. accounting _o látk.y

11.0 wt. mixed surfactant composition as in Example 1

5.0 wt. ethylene glycol

0.5 wt. MgO

0.3 wt. silicone defoamer

41.86% wt. technological] water

The dispersion stability of the freshly prepared sample was 100%, the sample was homogeneous, the dispersion stability of the sample stored for 14 days at 40 ° C S = 99.31%, no phasing occurred. Due to the presence of MgO, the mixed surfactant content could be reduced from 15% by weight. to 11% by weight.

Claims (4)

OBJECT OF THE INVENTION 1.0 to 10.0 8 wt. an antifreeze based on ethylene glycol and / or propylene glycol 0.05 to 2.0 wt. silicone antifoam and the rest up to 100% water A suspension-emulsion combination herbicidal composition based on 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, 4,6-bis (isopropylamino) -2-methylthio-1,3,5-triazine and 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) -chloroacetanilide comprising: 6.6 to 10.0 wt. 2-chloro-4-ethylamino-6-isopropylamino-l, 3,5-triazine 10.0 to 15.0% by weight of 4,6-bis (isopropylamino) -2-methylthio-1,3,5-triazine 20.0 to 30.0 wt. 2-ethyl-6-methyl-N- / l-methoxy-2-propyl / chloroacetanilide 10.0 to 16.0 8 wt. % of a mixed surfactant containing 25 to 35 wt. % alkylarylsulfonic acid calcium and 65 to 75 wt. copolymer of ethylene oxide with propylene oxide 0.1 to 1.0 wt. magnesium oxide stabilizers and / or powdered kraft liquor 2. A process for the preparation of a suspension-emulsion combination herbicidal composition according to claim 1, wherein the mixture is 2-chloro-4-ethylamino-6-isopropylamino-1, 3,5-triazine, The 4,6-bis (isopropylamino) -2-methylthio-1,3,5-triazine, mixed surfactant, stabilizer, antifreeze and water are homogenized, a silicone defoamer is added, the reaction mixture is ground on a colloid mill, at least 85% the particles must be less than or equal to 5 µm and finally 2-ethyl-6-methyl-N- (1-methoxy-2-propyl) -chloroacetanilide is added with vigorous stirring.