SUGAR SURFACTANTS AND USE THEREOF IN AGROCHEMICAL COMPOSITIONS

Abstract

A sugar surfactant of formula (I), where R.sup.1 is H or an alkyl group comprising 1 to 3 carbon atoms and R.sup.2 is a polyhydroxyhydrocarbyl group comprising a straight hydrocarbyl chain to which at least three hydroxyl groups are directly bonded, preferably a 2,3,4,5,6-pentahydroxyhex-1-yl group, is suitable especially for use in agrochemical adjuvant and active substance compositions.

##STR00001##

Claims

1. A sugar surfactant of the formula (I) ##STR00005## in which R.sup.1 is H or an alkyl group having 1 to 3 carbon atoms and R.sup.2 is a polyhydroxyhydrocarbyl group comprising a linear hydrocarbyl chain, where at least three hydroxyl groups are bonded directly to the chain.

2. The sugar surfactant as claimed in claim 1, wherein R.sup.1 is an alkyl group having 1 to 3 carbon atoms, R.sup.2 is —CH.sub.2—(CHOH).sub.n—CH.sub.2OH, —CH.sub.2—(CH.sub.2OH)(CHOH).sub.n-1—CH.sub.2OH, or —CH.sub.2—(CHOH).sub.2(CHOR.sup.3)(CHOH)—CH.sub.2OH, n is 3, 4 or 5 and R.sup.3 is H or a cyclic mono- or polysaccharide.

3. The sugar surfactant as claimed in claim 1, wherein R.sup.1 is methyl and R.sup.2 is —CH.sub.2—(CHOH).sub.4—CH.sub.2OH.

4. An aqueous adjuvant composition comprising A1) at least one sugar surfactant of the formula (I) as claimed in claim 1, A2) water, A3) optionally at least one cosolvent, A4) optionally at least one ammonium salt and A5) optionally at least one softener.

5. The adjuvant composition as claimed in claim 4, wherein in formula (I) R.sup.1 is a methyl group and R.sup.2 is CH.sub.2—C(CHOH).sub.4—CH.sub.2OH.

6. The adjuvant composition as claimed in claim 4, wherein the proportion of the at least one sugar surfactant (I) is 10% to 90% by weight, based on the total weight of the composition.

7. The adjuvant composition as claimed in claim 4, wherein the at least one cosolvent (A3) is selected from the group consisting of propylene glycol, dipropylene glycol, mixtures of propylene glycol and dipropylene glycol, each optionally in a mixture with polypropylene glycol and or polyethylene glycol, each having up to ten repeat units.

8. The adjuvant composition as claimed in claim 4, wherein the at least one ammonium salt (A4), is selected from the group consisting of ammonium sulfate, ammonium nitrate, ammonium nitrate urea, ammonium phosphate, ammonium citrate, ammonium chloride and ammonium thiosulfate.

9. A process for enhancement of the biological activity of at least one active agrochemical ingredient, comprising the step of contacting a plant with a composition comprising at least one sugar surfactant of the formula (I) ##STR00006## in which R.sup.1 is H or an alkyl group having 1 to 3 carbon atoms and R.sup.2 is a polyhydroxyhydrocarbyl group comprising a linear hydrocarbyl chain, where at least three hydroxyl groups are bonded directly to the chain, and the at least one active agrochemical ingredient.

10. A process for production of an aqueous active agrochemical ingredient composition comprising the step of mixing the at least one sugar surfactant of the formula (I) ##STR00007## in which R.sup.1 is H or an alkyl group having 1 to 3 carbon atoms and R.sup.2 is a polyhydroxyhydrocarbyl group comprising a linear hydrocarbyl chain, where at least three hydroxyl groups are bonded directly to the chain, with the at least one active agrochemical ingredient.

11. An active ingredient composition comprising W1) at least one sugar surfactant of the formula (I) as claimed in claim 1, (W2) water, (W3) at least one soluble active ingredient, (W4) optionally at least one cosolvent, (W5) optionally at least one ammonium salts, (W6) optionally at least one softener, (W7) optionally at least one auxiliaries, and (W8) optionally at least one water-insoluble active ingredient.

12. The active ingredient composition as claimed in claim 11, wherein the at least one water-soluble active ingredient is an active agrochemical ingredient.

13. The active agrochemical ingredient composition as claimed in claim 12, wherein the at least one water-soluble active agrochemical ingredient of component (W3) is selected from the group consisting of plant nutrients, plant fortifiers, plant growth regulators and herbicides.

14. The active agrochemical ingredient composition as claimed in claim 12, wherein the at least one water-soluble active agrochemical ingredient of component (W3) is selected from water-soluble salts of 2,4-D, bentazon, dicamba, fomesafen, glyphosate, glufosinate, MCPA, mesotrione, paraquat and sulcotrione.

15. The active agrochemical ingredient composition as claimed in claim 12, further comprising at least one water-insoluble active ingredient.

16. The active agrochemical ingredient composition as claimed in claim 12, wherein the total amount of the active agrochemical ingredients of component (W3) in the composition is greater than 100 g/L, based on the acid equivalent thereof.

17. The active agrochemical ingredient composition as claimed in claim 12, wherein the total amount of the sugar surfactants of the formula (I) in the composition is from 20 to 250 g/L.

18. The active agrochemical ingredient composition as claimed in claim 12, which comprises an ammonium salt (W5).

19. The active agrochemical ingredient composition as claimed in claim 12, which comprises, as well as component (W1), at least one further adjuvants.

20. The active agrochemical ingredient composition as claimed in claim 12, which takes the form of a concentrate formulation which is diluted prior to use and contains 5% to 80% by weight of the at least one water-soluble active agrochemical ingredient of component (W3) and 1% to 25% by weight of the at least one sugar surfactant of component (W1).

21. The active agrochemical ingredient composition as claimed in claim 12, which takes the form of a spray liquor and contains 0.001% to 10% by weight of the at least one water-soluble pesticide of component (W3) and 0.01% to 1% by weight of the at least one sugar surfactant of component (W1).

22. (canceled)

23. A method of protecting plants from harmful organisms, comprising the step of contacting the plant, the harmful organisms or their habitat with an active agrochemical ingredient composition, wherein the active agrochemical ingredient comprises a pesticide, and at least one sugar surfactant of the formula (I) ##STR00008## in which R.sup.1 is H or an alkyl group having 1 to 3 carbon atoms and R.sup.2 is a polyhydroxyhydrocarbyl group comprising a linear hydrocarbyl chain, where at least three hydroxyl groups are bonded directly to the chain.

24. The method as claimed in claim 23 for control and/or for abatement of unwanted plant growth, fungal disorders or insect infestation in plants.

25. The adjuvant composition as claimed in claim 4, wherein the at least one softener is selected from the group consisting of alkali metal phosphates, alkali metal citrates, alkali metal sulfates, glycerol sulfates, phosphonates, aminopolycarboxylic acids, aminopolyphosphonic acids, gluconates, monocarbamide dihydrogensulfate, polymeric polycarboxylates and polymeric polyphosphonates.

26. The active agrochemical ingredient composition as claimed in claim 12, which comprises at least one softener, selected from the group consisting of alkali metal phosphates, alkali metal citrates, alkali metal sulfates, glycerol sulfates, phosphonates, aminopolycarboxylic acids, aminopolyphosphonic acids, gluconates, monocarbamide dihydrogensulfate, polymeric polycarboxylates and polymeric polyphosphonates.

Description

WORKING EXAMPLES

[0127] The invention is further illustrated to the person skilled in the art hereinafter by examples, but these should in no way be considered as a restriction to the embodiments detailed.

Example 1: Production of an Aqueous Sugar Surfactant Composition of the Invention

[0128] The solution comprising 50% active N-methyl-N-dec-9-enoylglucamine substance was prepared as follows: first of all, 9-decenoic acid (Aldrich) was reacted with an excess of methanol to give methyl 9-decenoate. The methyl 9-decenoate was distilled and then reacted with N-methylglucamine in the presence of 1,2-propylene glycol as solvent according to EP 0 550 637 and obtained as a solid consisting of 90% active substance and 10% 1,2-propylene glycol. This solid was dissolved at 40 to 50° C. in water, so as to give a solution with a 50% content of N-methyl-N-dec-9-enoylglucamine. This is a clear colorless solution.

Example 2

[0129] Increasing the absorption of systemic active ingredients using the example of mesotrione and test system for measurement of the promotion of penetration of active ingredients

[0130] Surfactants can promote the absorption of (active) ingredients through membranes such as skin, films or the plant cuticle. As a “finite-dose” application, it is known for the single administration or application of a solution, cream, gel etc. to a membrane that the absorption of active ingredient can be influenced by some additives such as surfactants even after wetting. This effect is independent of the interfacial effect in water, is often highly concentration-dependent and takes place for the most part after evaporation of water and any solvents present rather than as a result of the interaction, for example, with active ingredient, membrane and environmental factors. For various surfactants, it is observed after addition to active ingredient preparations that the penetration of a particular active ingredient is promoted to an enormous degree by some surfactants, whereas others are entirely ineffective (Cronfeld, P, Lader, K. Baur, P. (2001). Classification of Adjuvants and Adjuvant Blends by Effects on Cuticular Penetration, Pesticide Formulations and Application Systems: Twentieth Volume, ASTM STP 1400, A. K. Viets, R. S. Tann, J. C. Mueninghoff, eds., American Society for Testing and Materials, West Conshohocken, Pa. 2001).

[0131] The potential of the test substances, which is independent of the surfactant action, to promote foliar absorption of active agrochemical ingredients was determined in membrane penetration tests with apple leaf cuticles for mesotrione. Mesotrione is the most important modern active herbicide ingredient and, like other important herbicides (for instance 2,4-D or dicamba), is a weak organic acid having a pKa of 3.1 in the range of 2-6 and has good systemic characteristics after absorption via the leaf cuticle. With a number of such acids or electrolyte active ingredients, consistently excellent promotion of absorption has already been found with Synergen GA (N-methyl-N-octanoyl/decanoylglucamine), especially together with ammonium sulfate in the case of use of water with alkaline earth metal contents, such as calcium ion contents, that are potentially antagonistic to acidic herbicides. The plant cuticle is a lipophilic solubility membrane (lipid membrane) without pores or holes, and the results described are also expected for other nonporous lipophilic solubility membranes with these or other electrolyte active ingredients. The principle of the method has been published (e.g. WO-A-2005/194844; Baur, 1997; Baur, Grayson and Schönherr 1999; Baur, Bodelon and Lowe, 2012), and only the specifics and differences in the method are elucidated hereinafter. The leaf cuticles were enzymatically isolated in the manner described in the literature from apple leaves of orchard trees in a commercial fruit growing facility near Frankfurt am Main in 2011. The stomata-free cuticles were first dried under air and then installed into stainless steel diffusion cells. After application to the original upper side of the leaf and evaporation of the test liquid, i.e. of the aqueous preparations of the active ingredients without or with the glucamide-containing spray liquids or comparative compositions, the diffusion cells were transferred into thermostatted blocks and charged with aqueous liquid. The water used to make up the aqueous test liquids was local tap water (of known composition). At regular intervals, aliquot samples were taken and the proportion of active ingredient penetrated was determined by HPLC. During the experiment, the temperature in the system (block, diffusion cells, liquids, etc.) and the air humidity above the spray coating on the cuticle were known exactly and were monitored. In the experiment, relative air humidity was constant throughout at 56% relative air humidity (air over supersaturated calcium nitrate) at a constant 25° C. The analytical determination by means of HPLC (1290 Infinity, Agilent) was effected after with a Kinetex column 30×2, 1 mm, 2.6μ C18 100A (Phenomenex), taking a 20 μL aliquot as injection volume at the specified times. In each case, the geometric mean values of the penetration for intact membranes at the mean measurement times are given. According to the variant (active ingredient×test additive/formulation), 7-8 repetitions were set up. The coefficient of variation was below 35%, which is a typical biological variability for penetration for numerous plants (Baur, 1997).

TABLE-US-00001 TABLE 1 Penetration of mesotrione (active ingredient concentration 0.3 g/L in spray liquid) in the presence of 0.75 g/L ammonium sulfate and of the glucamides Synergen GA (N-methyl-N-octanoyl/decanoylglucamine), N-methyl-N-dec-9-enoylglucamine and N-methyl-N-nonanoylglucamine (all with 50% active substance) Spray liquor Mean penetration in % after Test product concentration time (n = 4-8) 0.3 g/L ai (conc.) [%] 12-14 h 1 day Synergen GA 0.1 3.4 5.8 Synergen GA 0.25 4.4 7.1 Synergen GA 0.5 3.9 8.2 N-Methyl-N-dec-9- 0.1 3.5 7.3 enoylglucamine N-Methyl-N-dec-9- 0.25 6.1 15.0 enoylglucamine N-Methyl-N-dec-9- 0.5 6.0 12.0 enoylglucamine N-Methyl-N- 0.1 3.1 6.7 nonanoylglucamine N-Methyl-N- 0.25 2.3 4.4 nonanoylglucamine N-Methyl-N- 0.5 6.7 11.5 nonanoylglucamine * 25° C./56% rel. air humidity

[0132] The table shows that N-methyl-N-dec-9-enoylglucamine led to higher promotion of penetration of mesotrione compared to the linear mixture of C8 and C10 glucamide. N-Methyl-N-nonanoylglucamine, which was likewise tested as well, likewise falls short.

Example 3 Dynamic Surface Tension (Interfacial Activity)

[0133] In the case of plants that are difficult to wet, such as the cereal plants wheat, barley, triticale, rye and oats, in the case of further large-scale crops corn, rice, soya and oilseed rape, and also in the case of almost all weed grasses and numerous dicotyledonous weeds that are difficult to control, such as Chenopodium album or Euphorbium heterophyllum, the promotion of the adsorption of the spray liquid on the green parts of the plant is of crucial significance. This wetting agent effect was therefore also determined for the glucamides.

[0134] For a given application technique or parameters (nozzle, pressure, water application rate, distance from the plant surface), the value for the dynamic surface tension in [mN/m] correlates well with the adhesion on plants that are difficult to wet such as barley (or cereals in general) and weed grasses. A value of 50 mN/m (at 20-21° C.) with respect to water (72.8 mN/m) results in an improvement in the adhesion from “zero adhesion” to about 50% (Baur P, Pontzen R 2007. Basic features of plant surface wettability and deposit formation and the impact of adjuvants. In: R E Gaskin ed. Proceeding of the 8th International Symposium on Adjuvants for Agrochemicals. Publisher: International Society for Agrochemical Adjuvants (ISAA), Columbus, Ohio, USA). A value below 60 mN/m at 200 ms gives visibly better adsorption of aqueous spray liquids; in the case of standard flat jet nozzles, optimal wetting is achieved.

[0135] The positive wetting and sticking effects do of course also apply to other organisms and synthetic surfaces or technical applications, for instance for attainment of thin coatings on or the cleaning of surfaces.

[0136] The values for dynamic surface tension (Krüss PocketDyne BP2100, T 24.6° C.) are shown below at for the linear C810 glucamide and the decene glucamide and a pelargonamide.

TABLE-US-00002 TABLE Dynamic interfacial tension of glucamides (temperature 24.6° C.) Conc. Surface tension [mN/m] Substance [g/L] 20 ms 50 ms 100 ms 200 ms Synergen GA 0.6 70.8 69.6 68.5 66.5 Synergen GA 1.25 66.2 62.5 60.3 58.1 Synergen GA 2.5 58.2 53.4 51.4 48.7 Synergen GA 5 45.2 41.5 39.8 38.0 N-Methyl-N-dec-9- 0.6 70.2 68.9 67.6 67.4 enoylglucamine N-Methyl-N-dec-9- 1.25 66.4 63.7 61.8 61.0 enoylglucamine N-Methyl-N-dec-9- 2.5 59.7 56.6 55.5 54.1 enoylglucamine N-Methyl-N-dec-9- 5 50.5 48.3 47.7 46.6 enoylglucamine N-Methyl-N- 0.6 70.2 68.8 67.7 67.1 nonanoylglucamine N-Methyl-N- 1.25 66.0 63.7 62.6 61.1 nonanoylglucamine N-Methyl-N- 2.5 59.1 56.3 55.3 53.8 nonanoylglucamine N-Methyl-N- 5 47.7 45.6 45.2 44.3 nonanoylglucamine

[0137] The results for dynamic surface tension show that N-methyl-N-dec-9-enoylglucamine is a wetting agent of comparable suitability to Synergen GA (C810). The same applies to the pelargonic acid glucamide.

[0138] Example 3 also shows that the surprising result (example 2) of better promotion of penetration of mesotrione by the decene glucamide compared to Synergen GA (C810) does not correlate with the wetting properties.

Example 4

[0139] The plant compatibility of N-methyl-N-dec-9-enoylglucamine and pelargonic acid at the abovementioned concentrations of 0.6, 1.25, 2.5 and 5 g/L is just as good as that of Synergen GA and N-methyl-N-nonanoylglucamine. After application to poinsettia plants of the Princettia variety, there were no necroses or other symptoms in any case, whereas an ethoxylated lauryl alcohol at 1 g/L that was also tested caused distinct necroses within one day.