Patent Application
20210029991
The invention relates to trisiloxane alkoxylate compositions, and in particular, to surfactant compositions useful in chemical formulations having agricultural and other uses. Compositions in accordance with the invention are particularly useful with agrochemicals, more particularly with herbicides, insecticides, fungicides, biologicals and growth regulators.
Many chemical formulations benefit from the inclusion of surfactants. Surfactants can affect the surface tension of the formulation. This can affect the ability of the formulation to spread on the surface to which it is applied. For example, certain surfactants efficiently reduce surface tension. Therefore, they help spread the same amount of an agrochemical formulation over a greater area of the plant to which they are applied. Other agrochemicals are formulated to promote adherence to the plant to which they are applied. Choice of surfactant also affects droplet size and the speed of which the formulation will be taken up by a plant to which it is applied.
Surfactant compositions used with agrochemicals are often formulated to balance properties of different surfactant mixtures. Unfortunately, the formulation of agrochemicals typically results in a trade-off, balancing desired properties where a surfactant composition emphasizing one desired property is at the expense of other desirable properties. Formulating a composition to emphasize one attribute for the same total amount of surfactant is often at the expense of other properties. For example, some low surface tension formulations are ineffective at adhering to a plant and some surfactants are better than others at promoting uptake via the plant's stomata or otherwise. Improper balancing of surfactant properties can result in a chemical formulation that requires a relatively long rain-free period, does not spread well or which can be expensive to apply.
Accordingly, a surfactant composition is desirable that can provide a formulation that overcomes disadvantages of the prior art.
Generally speaking, in accordance with the invention, combinations of at least two trisiloxane surfactants in accordance with invention can unexpectedly provide synergistic improvements in at least spreading, adhering and/or uptake properties of chemical formulations containing those surfactants. This synergy is measured as compared to the properties that would be predicted from the linear additive properties of proportional amounts of the individual surfactants. For example, compositions in accordance with the invention can reduce dynamic surface tension more effectively (synergistically) than based on the surface tension reduction properties of proportional amounts of the individual components alone. Compositions in accordance with the invention can lead to synergistically improved spread area as well as droplet adhesion of agrochemical sprays on plant surfaces. Additionally, compositions in accordance with the invention can provide an unexpected synergistic increase in the level of stomatal infiltration or other plant uptake properties relative to the linearly additive combination and often, each of the individual components alone. The combination of improved droplet adhesion, spreading and uptake allow for broader formulation latitude, making it easier to balance overall desired performance, without overly diminishing desirable properties.
In accordance with preferred embodiments of the invention, an organosilicone surfactant composition is provided, comprising a mixture of at least two trisiloxane alkoxylates. In one embodiment of the invention, the first trisiloxane alkoxylate has a first, lower molecular weight, provides a first, greater reduction in surface tension and has less than 10 alkylene oxide units (i.e. polyoxyethylene or polyoxyethylene/polyoxypropylene copolymers). The second trisiloxane alkoxylate has a second, higher molecular weight, provides a second, lower reduction in surface tension and has 10 or more alkylene oxide units (i.e. polyoxyethylene or polyoxyethylene/polyoxypropylene copolymers). The combination of these two different surfactants provides synergistic improvement in spreading, adherence and/or uptake, as compared to the linearly additive properties predicted from the properties of the individual surfactants.
Each trisiloxane alkoxylate surfactant is independently selected from:
M1DM2
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
M3D1M4
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
A formulation comprising the surfactant compositions in accordance with the invention can comprise one or more of a herbicide, an insecticide, a fungicide, a plant growth regulator, a biological, a micronutrient or a fertilizer. The surfactants can be present in the formulation at a concentration between 0.1% and 95%, more preferably between 2.5% and 70%. Formulations in accordance with the invention can be sold as concentrates, which are intended to be diluted, typically with water, prior to application in the field. When used in a “Tank-mix” application where the formulation is ready to be applied in the field as intended, the concentration of the surfactants formulated in accordance with an embodiment of the invention is preferably between 0.005% and 2%.
For a fuller understanding of the invention, reference is had to the following description, taken in connection with the accompanying drawings, in which:
In the specification and claims herein, the following terms and expressions are to be understood as indicated.
The singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise.
Other than in the working examples or where otherwise indicated, all numbers expressing amounts of materials, reaction conditions, time durations, quantified properties of materials, and so forth, stated in the specification and claims are to be understood as being modified in all instances by the term “about”.
All methods described herein may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed.
No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
The terms, “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps, but will also be understood to include the more restrictive terms “consisting of” and “consisting essentially of.”
It will be understood that any numerical range recited herein includes all sub-ranges within that range and any combination of the various endpoints of such ranges or sub-ranges.
As used herein, integer values of stoichiometric subscripts refer to molecular species and non-integer values of stoichiometric subscripts refer to a mixture of molecular species on a molecular weight average basis, a number average basis or a mole fraction basis.
It will be further understood that any compound, material or substance which is expressly or implicitly disclosed in the specification and/or recited in a claim as belonging to a group of structurally, compositionally and/or functionally related compounds, materials or substances includes individual representatives of the group and all combinations thereof.
The term “adjuvant” means any composition, material or substance which increases the efficacy of a bioactive material.
The term “bioactive” refers to an agricultural chemical or material, including but not limited to pesticides, e.g., herbicides, fungicides, insecticides, acaricides and molluscides; plant nutrients; defoliants; and, plant growth regulators.
The term “agrochemical,” or “agricultural chemical,” as used herein shall be understood to refer to all bioactive compounds, biological materials including extracts, fractions and by-products thereof, living organisms including microorganisms, and the like, that are suitable for agricultural use such as pesticides, herbicides, fungicides, insecticides, nematocides, larvacides, mitocides, ovacides, plant growth regulators, seed treatment agents, etc.
The term “agricultural composition” refers to a composition that is applied to plants, weeds, landscapes, grass, trees, pastures, or for other agricultural applications. Agricultural compositions can be provided in concentrated or diluted form. An agricultural composition may or may not contain an agrochemical (agricultural chemical).
“Surfactants” can improve spray deposition properties by reducing the surface tension of the agricultural composition to which they are added, which may be a solution, mixture, dispersion or emulsion and thereby enhance droplet adhesion on foliar surfaces. As used herein, the term surfactant will include emulsifiers, dispersants and spreaders that affect the surface tension of compositions to which they are added.
The expression “hydrocarbon group” means any hydrocarbon from which one or more hydrogen atoms has been removed and is inclusive of alkyl, alkenyl, alkynyl, cyclic alkyl, cyclic alkenyl, cyclic alkynyl, aryl, aralkyl and arenyl groups and is inclusive of hydrocarbon groups containing at least one heteroatom.
The term “alkyl” means any monovalent, saturated straight, branched or cyclic hydrocarbon group; the term “alkenyl” means any monovalent straight, branched, or cyclic hydrocarbon group containing one or more carbon-carbon double bonds where the site of attachment of the group can be either at a carbon-carbon double bond or elsewhere therein; and, the term “alkynyl” means any monovalent straight, branched, or cyclic hydrocarbon group containing one or more carbon-carbon triple bonds and, optionally, one or more carbon-carbon double bonds, where the site of attachment of the group can be either at a carbon-carbon triple bond, a carbon-carbon double bond or elsewhere therein. Examples of alkyls include methyl, ethyl, propyl and isobutyl. Examples of alkenyls include vinyl, propenyl, allyl, methallyl, ethylidenyl norbornane, ethylidene norbornyl, ethylidenyl norbornene and ethylidene norbornenyl. Examples of alkynyls include acetylenyl, propargyl and methylacetylenyl.
An organosilicone surfactant composition in accordance with preferred embodiments of the invention comprises a combination, such as a mixture of at least two trisiloxane alkoxylates (TSA-1 and TSA-2) each independently selected from:
A first trisiloxane alkoxylate (TSA-1) having the general formula (I):
M1DM2
where
M1=(R1)(R2)(R3)SiO0.5
M2=(R4)(R5)(R6)SiO0.5
D=(R7)(R8)SiO
where
R1 R2 R3 R4 R5 and R7 are independently selected from the group consisting of a monovalent hydrocarbon radical having from 1-4 carbon atoms
either (R6 is R9 and R8 is Z) or (R6 is Z and R8 is R9),
where R9 is a monovalent hydrocarbon radical having from 1-4 carbon atoms.
Z is a polyalkyleneoxide group of the general formula:
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
where subscripts a is 2 to 9, b is 0 to 7, and c is 0 to 7, and satisfy the following relationships: 2≤a+b+c<10, with a≥2
and with the limitation that when b+c=0, then a is 5 to 9, preferably 6 to 8
R10 is a linear or branched divalent hydrocarbon group of 3 to 4 carbon atoms
R11 is selected from the group consisting of H, monovalent hydrocarbon radicals of from 1 to 6 carbon atoms and acetyl.
A second trisiloxane alkoxylate (TSA-2) having the general formula (II):
M3D1M4
where
M3=(R12)(R13)(R14)SiO0.5
M4=(R15)(R16)(R17)SiO0.5
D1=(R18)(R19)SiO
where
R12 R13 R14 R15 R17 and R18 are independently selected from the group consisting of a monovalent hydrocarbon radical having from 1-4 carbon atoms
either (R16 is R20 and R19 is Q) or (R16 is Q and R19 is R20)
where R20 is a monovalent hydrocarbon radical having from 1-4 carbon atoms.
Q is a polyalkyleneoxide group of the general formula:
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
where subscripts d is 3 to 35, e is 0 to 50, and f is 0 to 20, providing that e+f is ≥1, and satisfy the following relationships: 10≤d+e+f≤75 with d≥5. However, in other preferred embodiments, e+f is 0 to 50, preferably e+f is ≥1, and satisfy the following relationships: 10≤d+e+f≤75 with d≥5.
R22 is a linear or branched divalent hydrocarbon group of 3 to 4 carbon atoms
R23 is selected from the group consisting of H, monovalent hydrocarbon radicals of from 1 to 6 carbon atoms and acetyl.
In other preferred embodiments of the invention, the trisiloxane alkoxylate surfactant (spreader) composition of the invention comprises a mixture of at least two different trisiloxane alkoxylates,
where
M1DM2
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
M3D1M4
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
In another embodiment of the invention, the organosilicone surfactant (spreader) composition of the present invention comprises a mixture of at least two different trisiloxane alkoxylates, where
M1DM2
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
b. A second trisiloxane alkoxylate (TSA-2) having the general formula (VI):
M3D1M4
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
In yet another embodiment of the invention, the organosilicone surfactant (spreader) composition of the invention comprises a mixture of at least two different trisiloxane alkoxylates, where
M1DM2
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
b. a second trisiloxane alkoxylate (TSA-2) having the general formula (VIII):
M3D1M4
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
R22 is a linear or branched divalent hydrocarbon group of 3 to 4 carbon atoms
R23 is selected from the group consisting of H or methyl.
In still yet another embodiment the invention, an organosilicone surfactant (spreader) composition comprises a mixture of at least two different trisiloxane alkoxylates, where
M1DM2
—R10—O—[C2H4O]a—[C3H6O]b—[C4H8O]c—R11;
b. A second trisiloxane alkoxylate (TSA-2) having the general formula (X):
M3D1M4
—R22—O—[C2H4O]d—[C3H6O]e—[C4H8O]f—R23;
Method for Producing Trisiloxane Alkoxylate Components of the Present Invention:
One method of producing the trisiloxane alkoxylate components of the present invention is to react a molecule of a hydride intermediate of the following formula, with an olefinically (i.e. Allyl, or methallyl polyalkyleneoxide):
(CH3)3Si—O—Si(CH3)(H)—O—Si(CH3)3
Reaction of the hydride intermediate (heptamethyltrisiloxane) with one or more allyl- or methallyl polyethers, e.g., of the general formula:
H2C═CRk CH2—O—(C2H4O)a(C3H6O)b(C4H8O)c—R11, in which R11 is hydrogen or a monovalent hydrocarbon radical of from 1 to 6 carbon atoms and acetyl. Rk is hydrogen or methyl. Subscripts a, b and c are as previously defined, is carried out under catalytic hydrosilylation reaction conditions to provide polyether-modified trisiloxane alkoxylate compounds of the invention.
Suitable olefinically modified polyethers, including mixtures thereof, that may be reacted with the heptamethyltrisiloxane hydride intermediate to provide polyether-modified trisiloxane alkoxylate surfactants of the invention include polyethyleneglycol allylether, polyethyleneglycol polypropyleneglycol allylether, methoxy polyethyleneglycol allylether, methoxy polyethyleneglycol polypropyleneglycol allylether, butoxy polyethyleneglycol polyproplylene glycol allylether, methoxy polypropyleneglycol allylether, polyethyleneglycol polypropyleneglycol polybutyleneglycoll allylether, polyethleneglycol polybutyleneglycol allylether, polyethyleneglycol polypropyleneglycol polybutyleneglycol allylether, and their mixtures. The allyl- and methallyl-terminated polyethers include those of the random and block types.
Hydrosilylation catalysts and their use are well known in the art and include complexes of such metals as rhodium, ruthenium, palladium, osmium, iridium and platinum. Many types of platinum-containing hydrosilylation catalysts can be used herein, e.g., those having the formula PtCl2 olefin and HPtCl3 olefin as described in U.S. Pat. No. 3,159,601, hereby incorporated by reference. Other platinum-containing hydrosilylation catalysts include complexes of chloroplatinic acid with up to 2 moles per gram of platinum and an alcohol, ether, aldehyde and mixtures thereof as described in U.S. Pat. No. 3,220,972, hereby incorporated by reference. Additional platinum-containing hydrosilylation catalysts useful in preparing the polyether-modified trisiloxane alkoxylates of the present invention are described in U.S. Pat. Nos. 3,715,334, 3,775,452 and 3,814,730 (Karstedt's catalyst), hereby incorporated by reference. Further background concerning hydrosilylation may be found in J. L. Spier, “Homogeneous Catalysis of Hydrosilylation by Transition Metals”, in Advances in Organometallic Chemistry, volume 17, pages 407 through 447, F. G. A. Stone and R. West editors, published by Academic Press (New York, 1979), hereby incorporated by reference. Those skilled in the art can readily determine the effective amount of catalyst for a given hydrosilylation reaction. Generally, an amount of hydrosilylation catalyst ranging from about 0.1 to 50 parts per million by weight of the desired hydrosilylation will be satisfactory.
One process for preparing the polyether-modified trisiloxane alkoxylates of the invention can be considered to proceed as follows in Structure 1:
Uses for the Compositions of the Invention:
Compositions of the present invention may be utilized in a variety of forms: as liquid solutions, dispersions of solids in liquids, dispersions of liquids in liquids as the previously described emulsions, solid mixtures or solid solutions either separately or in the forms previously listed in combination one with the other.
Pesticide—Agriculture, Horticulture, Turf, Ornamental and Forestry:
Many pesticide applications require the addition of an adjuvant to the spray mixture to improve wetting and spreading on foliar surfaces. Often that adjuvant is a surfactant, which can perform a variety of functions, such as increasing spray droplet retention on difficult to wet leaf surfaces, enhance spreading to improve spray coverage, or to provide penetration of the herbicide into the plant cuticle. These adjuvants are provided either as a tank-side additive or used as a component in pesticide formulations.
Typical uses for pesticides include agricultural, horticultural, turf, ornamental, home and garden, veterinary and forestry applications. Pesticide compositions in accordance with the invention can include at least one pesticide, where the trisiloxane alkoxylate surfactants of the present invention are present at an amount sufficient to deliver between 0.005% and 2% to the final use concentration, either as a concentrate or diluted in a tank mix. Optionally the pesticidal composition may include excipients, cosurfactants, solvents, foam control agents, deposition aids, drift retardants, biologicals, micronutrients, fertilizers and the like.
The term pesticide herein means any compound used to destroy pests, e.g., rodenticides, insecticides, miticides, fungicides, and herbicides. Illustrative examples of pesticides that can be employed include, but are not limited to, growth regulators, photosynthesis inhibitors, pigment inhibitors, mitotic disrupters, lipid biosynthesis inhibitors, cell wall inhibitors, and cell membrane disrupters.
The amount of pesticide employed in formulations in accordance with the invention varies with the type of pesticide employed. More specific examples of pesticide compounds that can be used with the compositions of the invention are, but are not limited to, herbicides and growth regulators, such as: phenoxy acetic acids, phenoxy propionic acids, phenoxy butyric acids, benzoic acids, triazines and s-triazines, substituted ureas, uracils, bentazon, desmedipham, methazole, phenmedipham, pyridate, amitrole, clomazone, fluridone, norflurazone, dinitroanilines, isopropalin, oryzalin, pendimethalin, prodiamine, trifluralin, glyphosate, sulfonylureas, imidazolinones, clethodim, diclofop-methyl, fenoxaprop-ethyl, fluazifop-p-butyl, haloxyfop-methyl, quizalofop, sethoxydim, dichlobenil, isoxaben, bipyridylium compounds, dicamba and tembotrione.
Fungicide compositions that can be used with compositions in accordance with the invention include, but are not limited to, aldimorph, tridemorph, dodemorph, dimethomorph; flusilazol, azaconazole, cyproconazole, epoxiconazole, furconazole, propiconazole, tebuconazole and the like; imazalil, thiophanate, benomyl carbendazim, chlorothialonil, dicloran, trifloxystrobin, fluoxystrobin, dimoxystrobin, azoxystrobin, furcaranil, prochloraz, flusulfamide, famoxadone, captan, maneb, mancozeb, dodicin, dodine, and metalaxyl.
Insecticides, including larvacide, miticide and ovacide compounds that can be used with composition in accordance with the invention, include, but not are not limited to, Bacillus thuringiensis, spinosad, abamectin, doramectin, lepimectin, pyrethrins, carbaryl, primicarb, aldicarb, methomyl, amitraz, boric acid, chlordimeform, novaluron, bistrifluron, triflumuron, diflubenzuron, imidacloprid, diazinon, acephate, endosulfan, kelevan, dimethoate, azinphos-ethyl, azinphos-methyl, izoxathion, chlorpyrifos, clofentezine, lambda-cyhalothrin, permethrin, bifenthrin, cypermethrin and the like.
Fertilizers and Micronutrients:
Fertilizers or micronutrients that can be used with composition in accordance with the invention, include, but are not limited to, zinc sulfate, ferrous sulfate, ammonium sulfate, urea, urea ammonium nitrogen, ammonium thiosulfate, potassium sulfate, monoammonium phosphate, urea phosphate, calcium nitrate, boric acid, potassium and sodium salts of boric acid, phosphoric acid, magnesium hydroxide, manganese carbonate, calcium polysulfide, copper sulfate, manganese sulfate, iron sulfate, calcium sulfate, sodium molybdate, calcium chloride.
The pesticide or fertilizer may be a liquid or a solid. If a solid, it is preferable that it is soluble in a solvent, or the quaternary organosilicon surfactant of the present invention, prior to application, and the silicone may act as a solvent, or surfactant for such solubility or additional surfactants may perform this function.
Agricultural Excipients:
Buffers, preservatives and other standard excipients known in the art also may be included in formulations including compositions in accordance with the invention.
Solvents may also be included in formulations containing compositions in accordance with the invention. These solvents can be in a liquid state at room temperature. Examples include water, alcohols, aromatic solvents, oils (i.e. mineral oil, vegetable oil, silicone oil, and so forth), lower alkyl esters of vegetable oils, fatty acids, ketones, glycols, polyethylene glycols, diols, paraffinics, and so forth. Particularly preferred solvents include 2, 2, 4 trimethyl, 1 3 pentane diol and alkoxylated (especially ethoxylated) versions thereof as illustrated in U.S. Pat. No. 5,674,832 herein incorporated by reference, or n-methyl-pyrrilidone.
Cosurfactants:
Cosurfactants useful in formulations in accordance with the invention include nonionic, cationic, anionic, amphoteric, zwitterionic, polymeric surfactants, or any mixture thereof. Surfactants are typically hydrocarbon based, silicone based or fluorocarbon based.
Moreover, other cosurfactants, that have short chain hydrophobes that do not interfere with superspreading as described in U.S. Pat. No. 5,558,806 herein incorporated by reference can also be useful.
Preferred surfactants to be included in formulations in accordance with the invention include alkoxylates, especially ethoxylates, containing block copolymers including copolymers of ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof; alkylarylalkoxylates, especially ethoxylates or propoxylates and their derivatives including alkyl phenol ethoxylate; arylarylalkoxylates, especially ethoxylates or propoxylates. and their derivatives; amine alkoxylates, especially amine ethoxylates; fatty acid alkoxylates; fatty alcohol alkoxylates; alkyl sulfonates; alkyl benzene and alkyl naphthalene sulfonates; sulfated fatty alcohols, amines or acid amides; acid esters of sodium isethionate; esters of sodium sulfosuccinate; sulfated or sulfonated fatty acid esters; petroleum sulfonates; N-acyl sarcosinates; alkyl polyglycosides; alkyl ethoxylated amines; and so forth.
Specific examples of surfactants include alkyl acetylenic diols (SURFONYL—Air Products), pyrrilodone based surfactants (e.g., SURFADONE—LP 100—Ashland), 2-ethyl hexyl sulfate, isodecyl alcohol ethoxylates (e.g., RHODASURF DA 530—Rhodia), ethylene diamine alkoxylates (TETRONICS—BASF), ethylene oxide/propylene oxide copolymers (PLURONICS—BASF), Gemini type surfactants (Rhodia) and diphenyl ether Gemini type surfactants (e.g. DOWFAX—Dow Chemical).
Preferred surfactants also include ethylene oxide/propylene oxide copolymers (EO/PO); amine ethoxylates; alkyl polyglycosides; oxo-tridecyl alcohol ethoxylates, and so forth.
In a preferred embodiment of the invention, agrochemical formulations containing compositions in accordance with the invention further comprises one or more agrochemical ingredients. Suitable agrochemical ingredients include, but are not limited to, herbicides, insecticides, growth regulators, fungicides, miticides, acaricides, fertilizers, biologicals, plant nutritionals, micronutrients, biocides, paraffinic mineral oil, methylated seed oils (i.e. methylsoyate, methylcanolate, ethylsoyate and ethylcanolate), vegetable oils (such as soybean oil corn oil and canola oil), water conditioning agents such as Choice® (Loveland Industries, Greeley, Colo.) and Quest® (Helena Chemical, Collierville, Tenn.), modified clays such as Surround® (NovaSource), foam control agents, surfactants, wetting agents, dispersants, emulsifiers, deposition aids, antidrift components, and water.
Suitable agrochemical formulations are made by combining, in a manner known in the art, such as, by mixing one or more of the above components with the trisiloxane surfactant composition of the present invention, either as a tank-mix, or as an “In-can” formulation. The term “tank-mix” herein means the addition of at least one agrochemical to a spray medium, such as water or oil, at the point of use. The term “In-can” herein refers to a formulation or concentrate containing at least one agrochemical component. The “In-can” formulation may then be diluted to use-concentration at the point of use, typically in a Tank-mix, or it may be used undiluted.
The following examples are presented for purposes of illustration only and should not be construed as limiting.
Compositions in accordance with the invention may be prepared by the hydrosilation of 1,1,1,3,5,5,5 heptamethyltrisiloxane with an allylpolyalkyleneoxide, to yield a polyalkyleneoxide modified heptamethyltrisiloxane surfactant.
10 g (0.005 mol) of heptamethyl trisiloxane, 92 g (0.061 mol) of allylpolyethylene oxide (mw 1520 g/mol), along with 31 μl tributyl amine, were charged into a 3-neck flask attached with a condenser, under nitrogen, and heated at 80-82° C. With stirring, the mixture was catalysed with 102 μl chloroplatinic acid (10 ppm). The reaction is exothermic and the temperature was allowed to reach ˜100°. The reaction mixture was then maintained at a temperature of 85° C. for 2 h, at which point the product showed no residual heptamethyl trisiloxane (via alcoholic KOH test). The product was cooled to room temperature and filtered. The resulting product had an aqueous surface tension of 26.5 mN/m (0.1 wt %) and a critical micelle concentration of 0.006 wt % (ID: TSA-2A).
Other trisiloxane components of the present invention were made in a similar fashion as described above. Table 1 provides a description of the trisiloxane alkoxylate components for the primary trisiloxane alkoxylate components (TSA-1) of the invention.
Description of TSA-1 and TSA-2 Components:
Table 1 provides a description of the TSA-1 (Primary Trisiloxane Alkoxylate) components of the present invention.
[(CH3)3SiO]2Si(CH3)—CH2CH2CH2-O—(C2H4O)a(C3H6O)b(C4H8O)cR11
The general formula for TSA-2 components (Second Trisiloxane Alkoxylate) of the present invention are described below in Table 2.
[(CH3)3SiO]2Si(CH3)—CH2CH2CH2-O—(C2H4O)d(C3H6O)e(C4H8O)fR23
Comparative Organosilicon Surfactants
Note the Comparative organosilicon surfactants are the individual TSA-1 and TSA-2 components (Not blends).
Blends of the trisiloxane components of the invention were made by mixing the two TSA components in the desired ratio (Weight % or Wt/vol % as indicated below). Each blend is described in the examples below.
Spreading on cabbage leaf was determined using a droplet size of 0.5 μl; 12 replicate droplets of each treatment applied to 3 leaves, each taken from a different plant. All treatments contained fluorescent dye Blankophore-P, used at 0.5%. All treatments were readily solubilized in deionized water. Test samples of each blend were prepared at 0.1% and 0.2% (w/v).
Table 3 demonstrates that spreading of the TSA-Blends of the present invention gave an unexpected synergistic increase in spreading relative to a linear additive predicted value (weighted average of the spread value for the individual components). All of the blends at either 0.1% or 0.2% gave more than a 20% increase in spread area over the predicted value for the blends.
Spray droplet adhesion (as a % of impacted droplets) was determined using a piezoelectric droplet generator to form mono-sized droplets of approximately 600 μm (Stevens et al. (1993) Adhesion of spray droplets to foliage: The role of dynamic surface tension and advantages of organosilicone surfactants. Pestic. Sci., 38, 237-245). Droplets were impacted from a height of 53 cm, to leaves mounted at 22.5 degrees. Cabbage foliage (difficult-to-wet) was used as the impaction surface, with a leaf angle of 22.5°. All treatments contained fluorescent dye Blankophore-P, used at 1%.
Table 4 demonstrates that the compositions for the present invention provided similar or better droplet adhesion on cabbage leaf relative to the linear additive predicted value for the mixtures of TSA-1-A and TSA-2-A. In certain compositions, the mixing ratios of the selected surfactants was not optimal, but at least a statistically significant decrease was not observed, compared to the prediction. Adhesion increased with an increase in adjuvant concentration.
a. Means sharing common postscripts (e.g., ab and a and b) are not statistically significantly different (P 0.05, LSD test).
Certain agrochemicals, such as systemic herbicides, should penetrate or absorb into foliar surfaces (leaves) to be most effective. Many herbicides require a “Rain-free” period after application to provide time for adequate absorption into the leaf. If rain occurs too soon after an agrochemical application, there is a significant risk of wash-off, thereby increasing the potential of an unacceptable spray application with certain formulations. For example, 2,4-D Amine can require 1-6 hours after application, while glyphosate can require 2-6 hours (Duncan, C; Factors Affecting Herbicide Performance; Jan. 5, 2018; Techline Invasive Plant News). In both cases, the type of formulation will play a role in speed of absorptions.
Trisiloxane alkoxylates containing about 7-9 alkyleneoxide units (i.e. polyoxyethylene or polyoxyethylene/polyoxypropylene copolymers) can facilitate rapid uptake via stomatal flooding (infiltration). Stomatal flooding occurs rapidly (≤10 minutes after application). Agrochemicals taken into the plant in this way become rainfast, because they have migrated into the substomatal cavity of the leaf (inside the leaf) and therefore are resistant to wash-off by subsequent rainfall. This is a significant advantage, because it increases the reliability of agrochemical sprays.
The impact of the TSA-1/TSA-2 blends on the uptake of 14C-glyphosate (herbicide) solutions into bean leaf (Vicia fava) was determined at 10 minutes after application, according to the method described by Stevens et al., Contributions of stomatal infiltration and cuticular penetration to enhancements of foliar uptake by surfactants. Pestic. Sci., 33, 371-382, to establish the contribution of trisiloxane alkoxylate (TSA) surfactants on the speed of uptake, via stomatal infiltration). Here glyphosate solutions containing 0.4% TSA surfactant was applied to bean leaf using a micro-syringe. At 10 minutes after application, the leaf was washed with aqueous ethanol and uptake was determined by subtraction, using a scintillation counter to measure residual 14C-glyphosate-IPA salt (Stevens et al. Pestic. Sci., 33, 371-382).
Table 5 demonstrates that unexpectedly, compositions of the present invention significantly enhanced glyphosate uptake into the bean leaf, at 10 minutes after application. Blends of TSA-1-A and TSA-2-A (Run ID Nos. 2, 3, 4, 5 and 7) demonstrated uptake beyond what would be predicted from the addition of the two components. Uptake was unexpectedly increased between 2× and 6× the predicted value (weighted average for corresponding TSA-1 and TSA-2 blends) and demonstrated the synergy of combinations in accordance with the invention. Although TSA-1-A provided a high level of infiltration into bean leaf, as expected, it was unexpected that blends of TSA-1-A and TSA-2-A would provide a significant increase in uptake beyond that possible with TSA-1-A alone, especially since the contribution towards infiltration from TSA-2-A alone was negligible (0.1%). Similarly, the blend of TSA-1-B with TSA-2-A exhibited a 192% increase of the predicted weighted average predicted value for uptake.
Spreading was determined on an artificial surface using 0.1% (active) surfactant. TSA solutions were prepared in deionized water that was further purified with a Milli-Q ultrapure filtration system (Millipore Corp.). Thereafter, a 10 μL drop was placed on a polystyrene surface (Petri-dish) and the spread diameter measured (mm) after 30 seconds, while maintaining a relative humidity between 35 and 70%). Table 6 illustrates that the spreading properties for TSA-Blends of the present invention exhibited an unexpected increase in spreading, relative to a linear additive predicted value (weighted average of the spread value for the individual components). Blends containing a TSA-2 component with greater than 20% EO yielded an unexpected improvement in the spread diameter, over the predicted value for the blends. However, TSA-Blends containing TSA-2-B, which has less than or equal to 20% EO in the polyether chain, only exhibited improved spreading at blend ratios of 60% TSA-2-B or less. TSA-2-B levels above 60% appeared to be antagonistic toward spreading, indicating that under certain situations, such as those, TSA-2 components with low water solubility/dispersibility should be limited to 60% in the blend with TSA-1-A type components (EO/PO based), or used with TSA-1-B type components which have a higher level of water solubility/dispersibility to overcome the low water solubility of low EO containing TSA-2 type adjuvants (≤20 wt % EO).
Spreading was determined on cabbage-leaf (Natural surface) using the method outlined in Example 1, with the exception of the use rate. In this example, spreading was determined with the TSA surfactants comprising 0.4% of the applied agricultural composition.
Table 7 illustrates that TSA blends of the present invention provide improved spreading relative to the level of spreading predicted by a linear weighted average of the two components. All blends unexpectedly gave between a 36% and 88% increase in spreading over the predicted value.
The uptake by stomatal infiltration of 14C-glyphosate-isopropyl amine salt into bean-leaf (Vicia faba) at 10 minutes after application was determined as outlined in Example 4.
Tables 8A-D demonstrate that the compositions of the present invention provide an increase in uptake of glyphosate relative to the predicted value based on a linear regression. As with spreading, the blends containing TSA-2 components that show this synergy also provide spreading diameters greater than or equal to 20 mm (on a polystyrene surface).
For example, the TSA-1-A/TSA-2-B blends provide improved uptake when the TSA-2 component was present at a level less than 70 wt % (Table 8A). This also corresponds to the concentration where spreading exceeds the 20 mm spread diameter, which appears to be important for stomatal infiltration (See Spreading Example 5, Table 6, Treatments 12 to 13, and
14C-glyphosate into Bean at 10 Minutes After
14C-glyphosate into Bean at 10 Minutes After
14C-glyphosate into Bean at 10 Minutes After
Dynamic surface tension (DST) was measured using a Kruss Maximum Bubble Pressure tensiometer. TSA solutions were prepared at 0.4 wt % in deionized water, further purified with a Milli-Q ultrapure filtration system (Millipore Corp.). The data for surface tension vs time (milliseconds) was plotted and then the surface tension was calculated from a trend line to generate surface tension data at 75, 100, 150 and 200 milliseconds (mSec).
Surprisingly, some of the mixtures of the TSA-1 and TSA-2 yielded a lower DST than the individual TSA components alone, i.e., lower than the additive prediction. For example, this is observed with the 50/50 blend of TSA-1-A with TSA-2-C for DST between 75 and 200 mSec (Table 9).
Additionally, Table 9 shows the synergistic interaction for various blends of the TSA-1 and the TSA-2 components. Bold italics indicates a lower DST relative to either the TSA-1 or the TSA-2 component alone. Likewise, similar results were observed for TSA-1-B mixtures with TSA-2-A, where the blends exhibited a synergy, observed as a lower DST than the individual components alone.
This synergistic effect is further illustrated in
The aqueous surface tension was measured using a Kruss 11, equilibrium surface tensiometer with a platinum blade as the sensor. 0.1 and 0.4 wt %. TSA solutions were prepared in deionized water, further treated with a Milli-Q Ultra-pure filtration system (Millipore).
Table 10 demonstrates that all of the products that provided greater than 10% stomatal infiltration, as described in Example 7, had an equilibrium surface tension of ≤23 mN/m. Although not all TSAs that have a surface tension value of ≤23 mN/m gave stomatal infiltration, this demonstrates that a low aqueous equilibrium surface tension is one important factor for enhancing infiltration (See
This example demonstrates a benefit of using a mixture of at least two trisiloxane alkoxylates in accordance with the invention. For example, if a formulator intended to develop an adjuvant composition that would provide a minimum spread area of 80 mm2, and achievea high level of stomatal infiltration, along with a dynamic surface tension (DST) below 30 mN/m (Between 75 and 200 milliseconds).
While the invention has been described with reference to particular embodiments, those skilled in the art will understand that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. It is intended that the invention not be limited to the particular embodiments disclosed but that it include all embodiments falling within the scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201810106600.4 | Feb 2018 | CN | national |
This application claims priority to Chinese Patent Application No. 201810106600.4, filed Feb. 2, 2018; U.S. Provisional Application No. 62/627,992, filed Feb. 8, 2018; and U.S. Provisional Application No. 62/749,738, filed Oct. 24, 2018, the entire contents of each of these applications which are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2019/015997 | 1/31/2019 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62627992 | Feb 2018 | US | |
| 62749738 | Oct 2018 | US |
