Compositions and methods for formulating molten petroleum adjuvants to improve herbicide uptake into weed plants - Patent Application 20070122999

Abstract

A herbicide adjuvant composition for controlling weed plants is disclosed. The herbicide adjuvant composition includes a phenoxy-based herbicide and a petroleum-based adjuvant. The petroleum-based adjuvant may include a mixture of alicyclic hydrocarbons in the C17-C29 range and a hydrotreated heavy naphthenic fraction. The herbicide-adjuvant composition may also include a viscosity modifier. Granules coated with the herbicide-adjuvant composition are also disclosed. The granules may be fertilizer granules or carrier granules. A method for controlling weed plants includes applying a plurality of granules coated with the herbicide-adjuvant composition to the weed plants. The phenoxy-based herbicide and the petroleum-based adjuvant are applied to the weed plants in a single step.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 992,218, filed March 20, 2020, the contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION The present invention relates generally to molten petroleum adjuvants and methods for making molten petroleum adjuvants that improve the uptake of herbicides into weed plants. [Background technology]

[0003] Granular weed control products used in the consumer turf industry typically contain systemic herbicides such as 2,4-D, MCPP-p, and dicamba for foliar application to broadleaf post-emergence weeds. The active ingredient is generally applied to a granular inert carrier or fertilizer granules as a tack-on powder or in liquid form. The resulting granular material is then typically applied to broadleaf weed plants using a broadcast spreader to distribute the granules on the leaf surface. The particles adhere to moist leaves to dissolve the active ingredient, allowing it to penetrate weed cells and kill the plants.

[0004] Most weed plants have a protective waxy cuticle layer that prevents water-soluble active ingredients or other materials from penetrating into their cellular structure. Crop oil concentrates (COCs) and vegetable oils (e.g., methylated seed oil, MSO) are petroleum-based adjuvants classified as penetrating agents. This type of adjuvant can improve cuticle penetration by softening, plasticizing, or dissolving the cuticle wax, allowing herbicides to migrate into the more hydrophilic cellular regions beneath the cuticle. Application of crop oil concentrates or vegetable oils is achieved using a liquid solution. This action improves herbicide efficacy and can result in a reduction in the overall herbicide application rate. It would be desirable to provide a molten petroleum-based adjuvant that improves herbicide uptake into weed plants and reduces the labor costs and time required for adjuvant and herbicide application. Summary of the Invention [Means for solving the problem]

[0005] In one embodiment, the herbicide-adjuvant composition comprises a phenoxy-based herbicide and a petroleum-based adjuvant. The petroleum-based adjuvant may comprise a mixture of alicyclic hydrocarbons in the C17 to C29 range and hydrotreated heavy naphthenic fractions. The herbicide-adjuvant composition may also comprise a viscosity modifier.

[0006] In another embodiment, the granule is coated with the herbicide-adjuvant composition.The granule may be a fertilizer granule or a carrier granule.

[0007] In another embodiment, a method of preparing a herbicide-adjuvant composition comprises mixing a phenoxy-based herbicide and a petroleum-based adjuvant to form a solution. o F~280 o The process may be carried out at a temperature in the range of 100°C.

[0008] In another embodiment, the method of preparing the granules comprises coating the granules with the herbicide-adjuvant composition.

[0009] In another embodiment, a method for controlling weed plants comprises applying to the weed plants a plurality of granules coated with a herbicide-adjuvant composition, wherein the phenoxy-based herbicide and the petroleum-based adjuvant are applied to the weed plants in a single step. [Brief explanation of the drawings]

[0010] The above and other features and advantages of the present invention, and the means for achieving them, will become more apparent and better understood by reference to the following description of non-limiting embodiments of the invention, taken in conjunction with the accompanying drawings.

[0011] [Figure 1] FIG. 1 is a backscattered detection image of an example composition of one embodiment. [Figure 2] FIG. 2 is an elemental map of the composition of an example of one embodiment. [Figure 3] FIG. 3 is a chart showing estimated chlorine translocation levels for an example composition of one embodiment, a comparative composition including a herbicide treatment, and a control composition. [Figure 4] Figure 4 is a graph showing the percentage of dandelion control one month after application. [Figure 5] FIG. 5 shows electron images and elemental maps of both the comparative composition and the example composition of one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Disclosed herein are compositions and methods for formulating molten petroleum adjuvants. The compositions and methods of the present invention involve combining herbicides and adjuvants in a single manufacturing step without the use of solvents or tank solutions. Fertilizer or carrier granules coated with herbicide-adjuvant coatings are also disclosed. Thus, granular herbicides and enhanced-performance penetrants may be applied to plants without the need for separate application steps. The compositions and methods of the present invention improve herbicide efficacy and ease of use while reducing application costs for consumers.

[0013] Herbicide-adjuvant compositions of the embodiments include a phenoxy-based herbicide and a petroleum-based adjuvant. Examples of phenoxy-based herbicides include 2,4-dichlorophenoxyacetic acid (2,4-D), (2R)-2-(4-chloro-2-methylphenoxy)propionic acid (MCPP-p), 3,6-dichloro-2-methoxybenzoic acid (dicamba), and mixtures thereof. The herbicide-adjuvant compositions may include about 5% to about 25%, or about 10% to about 20% by weight of the petroleum-based adjuvant. In certain embodiments, the herbicide-adjuvant compositions may include 79% by weight of 2,4-D, 6% by weight of dicamba, and 15% by weight of the adjuvant. Furthermore, in certain embodiments, the herbicide-adjuvant compositions may include about 50% to about 95% of the herbicide. In addition to or as an alternative to a phenoxy-based herbicide, the composition may include a natural or plant-based derivative. Suitable derivatives include, but are not limited to, abietic acid, levopimaric acid, pimaric acid, dehydroabietic acid, dihydroabietic acid, rosin derivatives, pine wood resin derivatives, or combinations thereof.

[0014] Embodiments of petroleum-based adjuvants include mixtures of alicyclic hydrocarbons ranging from C17 to C29 and hydrotreated heavy naphthenic fractions. Alicyclic hydrocarbons include mixtures of tricyclic, tetracyclic, and pentacyclic naphthenic compounds (structures shown below). Examples of commercially available petroleum-based adjuvants include DUSTROL® 3088, manufactured and sold by ARR-MAZ Custom Chemicals, Inc., Mulberry, FL.

[0015] [ka]

[0016] In certain embodiments, the petroleum-based adjuvant comprises alicyclic hydrocarbons in the range of about 50% to about 95% by weight and a hydrotreated heavy naphthenic fraction in the range of about 5% to about 50% by weight. The overall molecular weight of the petroleum-based adjuvant is about 100% at room temperature (e.g., 65-80%). o However, at high temperatures (e.g., 250 o F~280 o F) The petroleum-based adjuvant has a viscosity of about 150 centipoise or less and a viscosity of about 300 o The hydrotreated heavy naphthenic fraction provides petroleum-based adjuvants with an aromatic carbon fraction ranging from about 1% to about 4%. This low level of aromatic content allows petroleum-based adjuvants to have high safety profiles. Furthermore, this level of aromatic content is sufficiently high to make petroleum-based adjuvants effective solvents for phenoxy-based herbicides such as 2,4-D, MCPP-p, and dicamba.

[0017] In certain embodiments, the herbicide-adjuvant composition includes a modifier or surfactant. For example, a viscosity modifier, such as dipropylene glycol (DPG), may be added to the herbicide-adjuvant composition. The viscosity modifier allows for lower processing temperatures, which reduces the likelihood of herbicide degradation during the mixing process. For example, in certain embodiments, the flash point of the viscosity modifier is 240 o F or greater. Additionally, the viscosity modifier may improve distribution of the active ingredient (AI) on the surface of the granule. In certain embodiments, the herbicide-adjuvant composition may include about 24% by weight of a viscosity modifier.

[0018] An embodiment of preparing a herbicide-adjuvant composition includes combining a phenoxy-based herbicide and a petroleum-based adjuvant at an elevated processing temperature. Such elevated processing temperatures can be, for example, 200 o F~280 oThe application temperature may range from 0.1 to 1.5°F. The application temperature may vary depending on the ratio of herbicide to adjuvant and whether the composition includes a modifier. The phenoxy-based herbicide is dissolved in a solution of the petroleum-based adjuvant. The herbicide-adjuvant solution is then applied to the surface of the fertilizer or carrier granules. The solution hardens as a coating when cooled (e.g., at room temperature).

[0019] In use, the herbicide-adjuvant coated granules are sprayed onto moist weed leaves, allowing the herbicide and adjuvant to spread. The solvent properties of the adjuvant help increase the percentage of active ingredient that spreads from the coated granules. The adjuvant softens the epidermal layer, allowing a high concentration of the herbicide to penetrate the leaf's cellular structure and be translocated by the plant. The high active ingredient translocation results in a greater percentage of weeds being killed compared to herbicides formulated without an adjuvant. [Example]

[0020] Example 1 Herbicide-Adjuvant Composition A laboratory-scale batch of a typical phenoxy-based herbicide melt was prepared. DUSTROL® 3088 was first added to a stirred tank and stirred for 265 minutes. o Once the DUSTROL® 3088 reached the target temperature, the o F~270 o The 2,4-D was slowly mixed in while maintaining the temperature in the range of 265°F. Once the 2,4-D was completely added, o F~270 o Dicamba was added to the vessel at a rate that maintained the temperature in the range of 275°F. Once the dicamba was completely added, the solution was heated to approximately 275°F. o The mixture was heated to 10°C and held for 10 minutes. This initial solution contained 15% by weight of adjuvant (DUSTROL® 3088), 79% by weight of the 2,4-D composition (97% purity), and 6% by weight of the dicamba composition (92% purity). Approximately 200 grams of final solution was prepared for this batch.

[0021] The melt was then applied to a fertilizer base in a batch blender to create a final herbicide formulation with a 1.21% concentration of 2,4-D (active ingredient) and a 0.08% concentration of dicamba (active ingredient). The fertilizer base had an NPK ratio of 28-0-3. The final product was cooled and placed in storage bags.

[0022] Efficacy comparison The effectiveness of the herbicide-adjuvant coated fertilizer in transporting active ingredients into weed leaves was compared to a fertilizer substrate treated with the target adjuvant-free herbicide. Three groups of two dandelion plants were grown under greenhouse conditions. The first group was a fertilizer granule control, but received no herbicide or adjuvant treatment ("Control Example"). The second group was treated with a herbicide and fertilizer containing 1.21% 2,4-D and 0.61% MCPP-p, but without an adjuvant, at a rate of 1.5 pounds of 2,4-D per acre ("Comparative Example 1"). The third group was treated with the herbicide-adjuvant coated fertilizer granules described above at a rate of 1.5 pounds of 2,4-D per acre ("Example 1"). The fertilizer in each of these examples had an NPK ratio of 28-0-3. Granules were applied to the surface of pre-moistened dandelion leaves in each group, and each group, including the control, was kept in the greenhouse for approximately 40 hours after treatment to allow for initial translocation of the herbicide into the dandelion cellular structure.

[0023] After a 40-hour holding period, approximately 1 cm from each dandelion plant 2Herbarium samples were collected using the following protocol. First, each dandelion plant was inspected for a visual indication of the dissolving area of ​​particles on the leaf surface. To reduce artifacts due to differences in the number of particles attached to the leaf surface, herbarium samples were collected only from areas where dissolution was confirmed. Each specimen was given additional hydration and placed in a scanning electron microscope (SEM) chamber, cooled to a temperature of -27°C and a pressure of 50 Pa. An accelerating voltage of 21 kV was used to penetrate the electron beam below the leaf surface. The penetration depth of the electron beam is very large, firing X-ray photons with a critical excitation energy that depends on the atomic number. The X-ray escape depth was estimated using a derived equation by Anderson and Hasler, which is useful for most elements.

[0024]

number

[0025] Electron images were then scanned using a backscatter detector and 850X magnification, along with an energy dispersive X-ray spectroscopy (EDS) detector. An example of a backscatter detector image is shown in Figure 1, where the surface cellular structure is clearly visible, along with several small surface crystals distributed around the edges of the region. If large, undissolved particles were present in the sample specimen area, they were removed from the surface before being placed in the SEM chamber. Using the EDS detector, an elemental map was created showing the subsurface location of elemental chlorine. This map provides the best estimate of how much active ingredient was essentially taken up by the plant, or the degree of chlorine translocation, after a 40-hour retention period. An example of this elemental map is shown in Figure 2, where the green coloring indicates a relatively uniform distribution of chlorine across the image area.

[0026] Finally, using the quantitative analysis function of the EDS system, the predicted mass fraction of chlorine can be calculated from the information in the elemental map. To reliably estimate the mass fraction of each chlorine using a similar standard, the chlorine concentration was calculated as the carbon concentration ratio (C:Cl) because the size and number of plant cells varied from image to image. Furthermore, because plants can uptake chlorine-containing compounds from the soil, the chlorine content was measured from the control group, and these values ​​were used to normalize the data. These comparative results, shown in Figure 3, indicate that the sample specimens in Example 1 had a significantly lower C:Cl ratio, averaging 89.9, compared to Comparative Example 1, which had a C:Cl ratio of 663.3. The lower the C:Cl ratio of the sample area of ​​interest, the higher the chlorine concentration of the sample. Therefore, compared to Comparative Example 1, more chlorine, and therefore more herbicide, entered the plant cells in Example 1.

[0027] Example 2 Two herbicide control efficiency tests were conducted comparing a methylene urea-based fertilizer with herbicide (Comparative Example 1) with a fertilizer with herbicide and adjuvant ("Example 2"). The adjuvant in Example 2 was the same as in Example 1. The fertilizer application rate for both materials was 0.8 pounds of nitrogen per 1000 square feet. The herbicide rate for both materials was 1.5 pounds of 2,4-D per acre. Comparative Example 1 contained 0.75 pounds of MCPP-p per acre, and Example 2 contained 0.1 pounds of dicamba per acre. Thus, Example 2 contains approximately 30% less herbicide when compared to Comparative Example 1. The materials were applied to a Kentucky bluegrass area infested with dandelions (Taraxacum officinale).

[0028] Treatments were weighed in grams prior to application to maintain accurate product delivery rates and applied using a standardized screen distribution box that covered each test plot area. All treatments were applied to dew-moistened foliage. Figure 4 shows the results of tests conducted to determine dandelion control. All tests were replicated, and weed control evaluations were conducted one month after application.

[0029] The results show that Example 2 controlled dandelions at a rate equal to or better than Comparative Example 1 while using about 30% less active ingredient.

[0030] Example 3 The study compared 2,4-D, dicamba and a 15% DUSTROL® mixture in 275 o While heating to 275°C produces an effective weed control product, the high treatment temperature can result in inconsistent weed control. o When processed at temperatures above 2,4-D, some degradation of 2,4-D may occur, leading to decreased solubility of the active ingredient. Decreased solubility of 2,4-D reduces plant uptake and results in variable weed control.

[0031] To improve the uniformity of product performance, the processing temperature was increased to 200°C by increasing the DUSTROL® content to 24% and including a viscosity modifier, dipropylene glycol (DPG), at approximately 24%. o Example 3 contained fertilizer base, 48.4% 2,4-D, 3.2% dicamba, 24% DUSTROL®, and 24% DPG. o At a processing temperature of F, the combination of 24% DUSTROL® and 24% DPG eliminates degradation issues and improves distribution of the active ingredient on the granule surface. Figure 5 shows a comparison of Comparative Example 1, which was made using a process using a higher temperature, with Example 3, which incorporated 24% DUSTROL® and 24% DPG and was processed at a lower temperature. Figure 5 shows the average data from two tests, with the light blue areas indicating elemental chlorine and also indicating the presence of 2,4-D. The higher coverage of light blue in the DUSTROL® / DPG sample suggests greater distribution of 2,4-D around the particle.

[0032] Using the SEM / EDS method described in Example 1, field-grown dandelion plants were treated with a fertilizer containing 1.21% 2,4-D and 0.61% MCPP-p herbicide without adjuvant ("Comparative Example 1") at a rate of 1.5 pounds of 2,4-D per acre. A second group was treated with a fertilizer containing 1.21% 2,4-D, 0.08% dicamba, and an adjuvant combination of DUSTROL® and DPG ("Example 3"). A third group served as a control and received no herbicide treatment ("Control Example"). Results from the SEM / EDS analysis are displayed in Table 1.

[0033] [Table 1]

[0034] The results consistently show that Example 3 has the lowest C:Cl ratio, indicating the presence of more chlorine in the sample.

[0035] Example 4 Selected sod plots were treated with a fertilizer containing 1.21% 2,4-D and 0.61% MCPP-p herbicide at a rate of 1.5 pounds of 2,4-D per acre and no adjuvant (Comparative Example 1), a fertilizer containing 1.21% 2,4-D, 0.08% dicamba, and 15% DUSTROL® at a rate of 1.5 pounds of 2,4-D per acre (Example 1), a fertilizer containing 1.21% 2,4-D, 0.08% dicamba, 24% DUSTROL®, and 24% DPG at a rate of 1.5 pounds of 2,4-D per acre (Example 3), and another treatment was a control with no herbicide spray. The results are shown in Table 2 below.

[0036] [Table 2]

[0037] The results show that the formulation of Example 3 shows the highest dandelion damage rating after 3 days, suggesting that this formulation may have penetrated the leaf surface faster.The advantage of faster penetration into the leaf is that more active ingredient can be taken up by the plant before rain or wind or foot traffic knocks particles off the leaf surface.This achieves better spray consistency and performance.

[0038] All percentages (%) herein are by weight of the total composition and are expressed as weight / weight %, %(w / w), w / w, w / w% or simply % unless otherwise specified.

[0039] The dimensions and values ​​disclosed herein are not to be understood as being strictly limited to the exact numerical values ​​recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a range of functionally equivalent values ​​surrounding that value.

[0040] Every maximum numerical limitation given throughout this specification is to be understood as including every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification is to be understood as including every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification is to be understood as including every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

[0041] All documents cited herein, including cross-references or related patents or applications, are incorporated herein by reference in their entirety, unless expressly excluded or limited. The citation of a document is not an admission that it is prior art with respect to any invention disclosed or claimed herein, or that it alone, or in combination with other references, teaches, suggests, or discloses such invention. Furthermore, to the extent that a definition or meaning of a term in this specification conflicts with a definition or meaning of the same term in a document incorporated by reference, the definition or meaning assigned to the term in that document shall control.

[0042] The foregoing description of embodiments and examples has been presented for purposes of illustration. It is not intended to be exhaustive or to be limited to the forms described. Numerous modifications are possible in light of the above teachings. Some of these variations will be discussed, and others will be apparent to those skilled in the art. The embodiments were chosen and described in order to illustrate various embodiments. The scope is, of course, not limited to the examples or embodiments set forth herein, and any number of variations and equivalents may be employed by those skilled in the art. Rather, the scope is intended to be defined by the claims appended hereto.

Claims

1. phenoxy-based herbicides, and Petroleum-based adjuvants 1. A herbicide-adjuvant composition comprising: the herbicide comprises at least one of 2,4-dichlorophenoxyacetic acid (2,4-D) and 3,6-dichloro-2-methoxybenzoic acid (dicamba); the petroleum-based adjuvant comprises a mixture of alicyclic hydrocarbons in the range of C17 to C29 and a hydrotreated heavy naphthenic fraction; The composition further comprises a viscosity modifier.

2. The composition described in claim 1, further comprising (2R)-2-(4-chloro-2-methylphenoxy)propionic acid (MCPP-p).

3. 3. The composition according to claim 1, wherein the petroleum-based adjuvant is present in an amount ranging from 10% to 20% by weight.

4. 3. The composition of claim 1 or 2, wherein the mixture of alicyclic hydrocarbons comprises a mixture of tricyclic, tetracyclic and pentacyclic naphthenic compounds.

5. 5. The composition of claim 1, wherein the petroleum-based adjuvant comprises the alicyclic hydrocarbon in the range of 50% to 95% by weight and the hydrotreated heavy naphthenic fraction in the range of 5% to 50% by weight.

6. The composition of any one of claims 1 to 5, wherein the petroleum-based adjuvant has an aromatic carbon fraction in the range of 1% to 4%.

7. 7. A composition according to any one of claims 1 to 6, wherein the petroleum-based adjuvant has a viscosity of 150 mPa s (150 centipoise) or less at a temperature in the range of 121°C to 138°C (250°F to 280°F) and a flash point of 149°C (300°F) or more.

8. The composition of claim 1 wherein the viscosity modifier is dipropylene glycol.

9. Granules coated with the composition of any one of claims 1 to 7.

10. 10. The granule of claim 9 which is a fertilizer granule.

11. 10. The granule of claim 9 which is a carrier granule.

12. 8. A method of preparing the composition of any one of claims 1 to 7, comprising mixing the phenoxy-based herbicide and the petroleum-based adjuvant to form a solution.

13. 13. The method of claim 12, wherein the mixing occurs at a temperature ranging from 93°C to 138°C (200°F to 280°F).

14. A method for preparing granules according to any one of claims 9 to 11, comprising coating said granules with the composition according to any one of claims 1 to 7.

15. 12. A method of controlling weed plants comprising applying to the weed plants a plurality of granules according to any one of claims 9 to 11, wherein the phenoxy-based herbicide and the petroleum-based adjuvant are applied to the weed plants.

16. 16. The method of claim 15, wherein at least a portion of a plurality of said granules comprise fertilizer, and said fertilizer, said phenoxy-based herbicide and said petroleum-based adjuvant are applied to said weed plants.

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