High residual effect and low off-site movement auxin herbicide formulations

Abstract

The present invention generally relates to high residual effect and/or low off-site movement anionic herbicide formulations and, more particularly, auxin herbicide formulations. Generally, the formulations of the present invention include an anionic herbicide (e.g., an auxin herbicide), a particulate sorbent (e.g., silica), a cationic surfactant, and water.

What is claimed is: 
     
         1 . An aqueous herbicidal formulation, the formulation comprising:
 an anionic herbicide, a particulate sorbent, and a cationic surfactant, wherein:   the cationic surfactant is bonded to the particulate sorbent and the anionic herbicide is bonded to the cationic surfactant bound to the particulate sorbent,   the particulate sorbent has a silica content of at least about 50 wt. %, and   the concentration of anionic herbicide is at least about 0.1 wt % a.e.   
     
     
         2 . The formulation of  claim 1  wherein the particulate sorbent has a silica content of at least about 60 wt. %, at least about 70 wt. %, at least about 80 wt. %, at least about 90 wt. %, or at least about 95 wt. %. 
     
     
         3 . The formulation of  claim 1  or  2  wherein the cationic surfactant bonded to the particulate sorbent forms a micelle and herbicide anions are bound to the micelle structure. 
     
     
         4 . The formulation of  claim 3  wherein the micelle structure includes hydrophobic moieties of the cationic surfactant bound together. 
     
     
         5 . The formulation of any of  claims 1  to  4  wherein the anionic herbicide is non-protonated. 
     
     
         6 . The formulation of any of  claims 1  to  5  wherein the anionic herbicide has a water solubility of at least about 10 g/L at 25° C., at least about 25 g/L at 25° C., at least about 50 g/L at 25° C., at least about 75 g/L at 25° C., or at least about 100 g/L at 25° C. 
     
     
         7 . The formulation of any of  claims 1  to  6  wherein the anionic herbicide is an auxin herbicide selected from the group consisting of 2,4-D, 2,4-DB, MCPA, MCPB, aminocyclopyrachlor, aminopyralid, clopyralid, dichloroprop, fluroxypyr, triclopyr, diclopyr, mecoprop, mecoprop-P, dicamba, picloram and quinclorac, racemic mixtures and resolved isomers thereof, and combinations thereof. 
     
     
         8 . The formulation of any of  claims 1  to  7  wherein the anionic herbicide is an auxin herbicide salt selected from the group consisting of the sodium, potassium, ammonium, lithium, diammonium, monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, dimethylamine, diethylamine, triethylamine, methylamine, ethylamine, diglycolamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, dodecylamine and decylamine salts, and combinations thereof. 
     
     
         9 . The formulation of any of  claims 1  to  6  wherein the anionic herbicide is selected from the group consisting of dicamba, triclopyr, 2,4-D, and combinations thereof. 
     
     
         10 . The formulation of any of  claims 1  to  6  wherein the anionic herbicide is selected from the group consisting of dicamba, 2,4-D, and combinations thereof. 
     
     
         11 . The formulation of any of  claims 1  to  6  wherein the anionic herbicide is dicamba. 
     
     
         12 . The formulation of  claim 11  wherein the anionic herbicide is the monoethanolamine, diethanolamine, sodium, potassium, isopropylamine, diglycolamine or dimethylamine salt of dicamba, or a combination thereof. 
     
     
         13 . The formulation of  claim 12  wherein the anionic herbicide is the monoethanolamine, diethanolamine or potassium salt of dicamba, or a combination thereof. 
     
     
         14 . The formulation of  claim 12  wherein the anionic herbicide is the diglycolamine salt of dicamba. 
     
     
         15 . The formulation of any of  claims 1  to  14  wherein the particulate sorbent has a BET surface area of from about 90 to about 300 m 2 /g, from about 100 to about 250 m 2 /g, or from about 100 to about 200 m 2 /g. 
     
     
         16 . The formulation of any of  claims 1  to  15  wherein the particulate sorbent has a negative charge at a pH of from about 2 to about 3. 
     
     
         17 . The formulation of any of  claims 1  to  16  wherein the anionic herbicide is present at a concentration of from about 0.1 to about 80 wt. % a.e., from about 1 to about 60 wt. % a.e., from about 5 to about 60 wt. % a.e, from about 5 to about 50 wt % a.e., from about 10 to about 40 wt. % a.e., from about 10 to about 30 wt. % a.e., or from about 10 to about 20 wt. % a.e. 
     
     
         18 . The formulation of any of  claims 1  to  17  wherein the anionic herbicide is present in a proportion of from about 10 to about 800 g a.e./l, from about 20 to about 750 g a.e./l, from about 100 to about 750 g a.e./l, from about 200 to about 600 g a.e./l, from about 250 to about 550 g a.e./l, from about 300 to about 450 g a.e./l, from about 300 to about 400 g a.e./l, from about 325 to about 375 g a.e./l, or about 360 g a.e./l. 
     
     
         19 . The formulation of any of  claims 1  to  18 , wherein the formulation has a pH of from about 2 to about 10, from about 3 to about 8, or from about 4 to about 8. 
     
     
         20 . The formulation of any of  claims 1  to  19  wherein the molar ratio of the cationic surfactant to the anionic herbicide is at least about 0.2:1, at least about 0.5:1, or at least about 1:1. 
     
     
         21 . The formulation of any of  claims 1  to  20  wherein the molar ratio of the cationic surfactant to the anionic herbicide is less than about 8:1, less than about 6:1, or less than about 4:1. 
     
     
         22 . The formulation of any of  claims 1  to  21  wherein the molar ratio of the cationic surfactant to the anionic herbicide is from about 0.2:1 to about 8:1, from about 0.2:1 to about 6:1, or from about 0.2:1 to about 4:1, from about 0.5:1 to about 3:1, or from about 1:1 to about 2:1. 
     
     
         23 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises quaternary alkyl ammonium ions of the formula (I): 
       
         
           
           
               
               
           
         
       
       wherein R 1 , R 2 , R 3 , and R 4  are hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 1 to 15 carbon atoms. 
     
     
         24 . The formulation of  claim 23  wherein R 1  is a hydrocarbyl or substituted hydrocarbyl having from 5 to 25 carbon atoms or from 6 to 22 carbon atoms. 
     
     
         25 . The formulation of  claim 23  wherein R 1  is a hydrocarbyl or substituted hydrocarbyl having from 12 to 20 carbon atoms and R 2 , R 3 , and R 4  are methyl. 
     
     
         26 . The formulation of  claim 23  wherein R 1 , R 2 , R 3 , and R 4  are ethyl. 
     
     
         27 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises pyrdinium ions of the formula (II): 
       
         
           
           
               
               
           
         
       
       wherein R 10  is hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 10 to 20 carbon atoms. 
     
     
         28 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises bipyridinium ions of the formula (III): 
       
         
           
           
               
               
           
         
       
       wherein R 20  and R 25  are hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 1 to 15 carbon atoms. 
     
     
         29 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises pyrrolinium ions of the formula (IV): 
       
         
           
           
               
               
           
         
       
       wherein R 30  is hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 1 to 15 carbon atoms. 
     
     
         30 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises imidazolium ions of the formula (V): 
       
         
           
           
               
               
           
         
       
       wherein R 35  and R 40  are hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 1 to 15 carbon atoms. 
     
     
         31 . The formulation of any of  claims 1  to  22  wherein the cationic surfactant comprises benzalkonium ions of the formula (VI): 
       
         
           
           
               
               
           
         
       
       wherein R 45 , R 50 , R 55  are hydrocarbyl or substituted hydrocarbyl having from 1 to 25 carbon atoms, from 1 to 20 carbon atoms, or from 1 to 15 carbon atoms. 
     
     
         32 . The formulation of any of  claims 1  to  31 , the formulation further comprising ions of a second herbicide selected from the group consisting of glyphosate, acetochlor, and combinations thereof. 
     
     
         33 . The formulation of  claim 32 , the formulation further comprising glyphosate. 
     
     
         34 . An aqueous herbicidal formulation, the formulation comprising:
 dicamba, particulate silica, and a cationic surfactant, wherein:   the cationic surfactant is bonded to the particulate silica and dicamba is bonded to the cationic surfactant bound to the silica particles, the formulation further comprising glyphosate.   
     
     
         35 . The formulation of  claim 34  wherein dicamba anions are bonded to the particulate silica. 
     
     
         36 . The formulation of  claim 34  or  35 , wherein the glyphosate is a glyphosate salt selected from the group consisting of the potassium salt, isopropylammonium salt, and combinations thereof. 
     
     
         37 . The formulation of any of  claims 32  to  36  wherein glyphosate is present at a concentration of from about 0.1 to about 80 wt. % a.e., from about 1 to about 60 wt. % a.e., from about 5 to about 60 wt. % a.e, from about 5 to about 50 wt % a.e., from about 10 to about 40 wt. % a.e., from about 10 to about 30 wt. % a.e., or from about 10 to about 20 wt. % a.e. 
     
     
         38 . The formulation of any of  claims 33  to  36  wherein glyphosate is present in a proportion of from about 10 to about 800 g a.e./l, from about 20 to about 750 g a.e./l, from about 100 to about 750 g a.e./l, from about 200 to about 600 g a.e./l, from about 250 to about 550 g a.e./l, from about 300 to about 450 g a.e./l, from about 300 to about 400 g a.e./l, from about 325 to about 375 g a.e./l, or about 360 g a.e./l. 
     
     
         39 . An aqueous herbicidal formulation, the formulation comprising:
 an auxin herbicide, a particulate sorbent, and a cationic surfactant, wherein:   the cationic surfactant is bonded to the particulate sorbent and the auxin herbicide is bonded to the cationic surfactant bound to the particulate sorbent, and   the auxin herbicide concentration is at least about 0.1 wt. %.   
     
     
         40 . An adjuvant for an aqueous herbicidal formulation, the adjuvant comprising silica particles and a cationic surfactant, wherein the cationic surfactant is bonded to the silica particles, and the adjuvant has a silica (SiO 2 ) content of at least about 20 wt. %. 
     
     
         41 . A method for controlling weeds in a field of crop plants, the method comprising:
 applying an aqueous herbicidal formulation to the field in an herbicidally effective amount, wherein the aqueous herbicidal formulation is as defined in any of  claims 1  to  39 .   
     
     
         42 . The method of  claim 41  wherein the crop plant is selected from the group consisting of soybeans, cotton, peanuts, rice, wheat, canola, alfalfa, sugarcane, sorghum, and sunflowers. 
     
     
         43 . The method of  claim 42  wherein the crop plant is selected from the group consisting of corn, soybean, and cotton. 
     
     
         44 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field prior to planting the crop plant. 
     
     
         45 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field at any time during an interval from about 40 days, from about 30 days, from about 25 days, from about 20 days, from about 15 days, from about 10 days, or from about 5 days prior to planting of the crop plant to immediately prior to planting the crop plant. 
     
     
         46 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field preemergence to the crop plant. 
     
     
         47 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field at any time during an interval from about 1 day after planting, from about 2 days after planting, from about 3 days after planting, from about 4 days after planting, from about 5 days after planting, from about 10 days after planting, from about 15 days after planting, or from about 20 days after planting of the crop plant up to, but not including, emergence of the crop plant. 
     
     
         48 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field postemergence to the crop plant. 
     
     
         49 . The method of any of  claims 41  to  43  wherein the formulation is applied to the field at any time during an interval up to about 1 day after emergence, up to about 2 days after emergence, up to about 3 days after emergence, up to about 4 days after emergence, up to about 5 days after emergence, up to about 10 days after emergence, up to about 15 days after emergence, or up to about 20 days after emergence of the crop plant. 
     
     
         50 . The method of any of  claims 41  to  49  wherein the formulation comprises dicamba and the crop plants comprise transgenic dicamba-tolerant plants. 
     
     
         51 . The method of any of  claims 41  to  50  wherein the formulation comprises glyphosate and the crop plants comprise glyphosate-tolerant crop plants. 
     
     
         52 . The method of any of  claims 41  to  51  wherein the weeds comprise one or more glyphosate-resistant species and the formulation comprises dicamba. 
     
     
         53 . The method of any of  claims 41  to  52  wherein the weeds comprise one or more dicamba-resistant species and the formulation further comprises glyphosate. 
     
     
         54 . The method of any of  claims 41  to  53  wherein the formulation is applied to the field preemergence to the weeds. 
     
     
         55 . The method of any of  claims 41  to  53  wherein the formulation is applied to the field at any time during an interval from about 40 days, from about 30 days, from about 25 days, from about 20 days, from about 15 days, from about 10 days, or from about 5 days preemergence of the weeds. 
     
     
         56 . The method of any of  claims 41  to  53  wherein the formulation is applied to the field postemergence to the weeds. 
     
     
         57 . The method of any of  claims 41  to  53  wherein the formulation is applied to the field at any time during an interval up to about 1 day after emergence, up to about 2 days after emergence, up to about 3 days after emergence, up to about 4 days after emergence, up to about 5 days after emergence, up to about 10 days after emergence, up to about 15 days after emergence, or up to about 20 days after emergence of the weeds. 
     
     
         58 . A method for improving the residual effectiveness of an anionic herbicide, the method comprising:
 combining an anionic herbicide, a particulate sorbent, a cationic surfactant, and water, thereby forming an aqueous herbicidal formulation wherein the cationic surfactant is bonded to the particulate sorbent and the anionic herbicide is bonded to the cationic surfactant bound to the particulate sorbent.   
     
     
         59 . The method of  claim 58  wherein the particulate sorbent and cationic surfactant are combined with the anionic herbicide as an adjuvant, the adjuvant comprising the cationic surfactant bonded to the particulate sorbent. 
     
     
         60 . The method of  claim 58  or  59  wherein the anionic herbicide is an auxin herbicide.