WO2017092951A1 - Domain particles of pesticide particles embedded in an ionic acrylate copolymer - Google Patents

Domain particles of pesticide particles embedded in an ionic acrylate copolymer Download PDF

Info

Publication number
WO2017092951A1
WO2017092951A1 PCT/EP2016/076398 EP2016076398W WO2017092951A1 WO 2017092951 A1 WO2017092951 A1 WO 2017092951A1 EP 2016076398 W EP2016076398 W EP 2016076398W WO 2017092951 A1 WO2017092951 A1 WO 2017092951A1
Authority
WO
WIPO (PCT)
Prior art keywords
acrylate
particles
domain particles
domain
pesticide
Prior art date
Application number
PCT/EP2016/076398
Other languages
French (fr)
Inventor
Marion Winkelmann
Yannick Fuchs
Murat CETINKAYA
Susanne Steiger
Original Assignee
Basf Se
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Se filed Critical Basf Se
Publication of WO2017092951A1 publication Critical patent/WO2017092951A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
    • A01N25/02—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing liquids as carriers, diluents or solvents
    • A01N25/04—Dispersions, emulsions, suspoemulsions, suspension concentrates or gels
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
    • A01N25/08—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing solids as carriers or diluents
    • A01N25/10—Macromolecular compounds
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
    • A01N25/26—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests in coated particulate form
    • A01N25/28—Microcapsules or nanocapsules

Definitions

  • the present invention relates to domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising alkyl (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form; and to a process for preparing an aqueous dispersion of the domain particles comprising the steps of a) providing an aqueous suspension of a pesticide in form of coarse particles and subjecting the aqueous suspension to a milling in order to comminute the coarse particles; and b) performing a radical polymerization of a monomer mix comprising an alkyl(meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in the aqueous suspension; wherein the milling of step a) is performed in the presence of at least a portion of the monomer mix; or wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the mill
  • domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising alkyl (meth)acrylate, a water-soluble ionic acrylate, and option- ally an acrylate crosslinker in polymerized form.
  • the domain particles usually have an asymmetric form.
  • the domain particles usually have a form which is distinct from a sphere.
  • the surface of the domain particles has a plurality of indentations, which have a depth of at least 10 % (preferably at least 15%, and in particular at least 20%) of the average diameter D50 of the domain particle.
  • the depth of the indentations may be measured under a microscope.
  • the pesticide particles often agglomerate resulting in domain particles.
  • the domain particles usually contain a plurality of pesticide particles, which are at least partially coated with the copolymer.
  • the domain particles may have an average diameter D50 from 1 to 20 pm, preferably from 3 to 15 pm, and in particular from 5 to 12 pm.
  • the domain particles may have an average diameter D90 from 3 to 90 pm, preferably from 5 to 75 pm, and in particular from 7 to 60 pm.
  • the domain particle size may be determined by light scattering.
  • the domain particle size may be determined directly after the preparation of the domain particles.
  • the term "plurality of pesticide particles" means usually that at least two (preferably at least three) pesticide particles are present in a domain particle.
  • a domain particle may comprise up to 100 pesticide particles, preferably up to 50.
  • the pesticide particles may have an average diameter D50 from 0,5 to 10 pm, preferably from 0,7 to 4 pm, and in particular from 0,8 to 2 pm.
  • the pesticide particles may have an average diameter D90 from 1 to 12 pm, preferably from 2 to 8 pm, and in particular from 3 to 5 pm.
  • the pesticide particle size may be determined by light scattering. The pesticide particle size may be determined directly after the milling of the coarse patricles.
  • embedded in a copolymer usually refers to pesticide particles, which are at least partially in direct contact with the copolymer.
  • a typical example of such embedded pesticide particles is shown in Figure 1.
  • a majority of the pesticide particles are covered by the co- polymer.
  • the copolymer forms a homogenous phase, in which the plurality of pesticide particles is embedded.
  • the copolymer comprises alkyi (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form.
  • the copolymer may comprise further monomers. Usu- ally, the copolymer is a random copolymer.
  • the alkyi (meth)acrylate is typically Ci-Ce alkyi acrylate or Ci-Ce alkyi methacrylate, and preferably C1-C4 alkyi acrylate or C1-C4 alkyi methacrylate, and in particular methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, or butyl methacrylate. Mixtures of alkyi (meth)acry- late are also suitable.
  • the term "(meth)acrylate” refers to acrylate and/or methacrylate.
  • the ionic acrylate may have a solubility in water of at least 5 g/l, preferably at least 10 g/l, and in particular at least 20 g/l, each at 20 °C.
  • Suitable ionic acrylates are acrylates or methacrylates which comprise at least one anionic group (e.g. an acid group) or cationic group, wherein cationic groups are preferred.
  • Suitable ionic acrylates which comprise an anionic group are acrylates or methacrylates exhibiting a sulfonic acid group, a phosphonic acid group or one or two carboxylic acid groups, and their salts (preferably the alkali metal salts, e.g. the sodium or potassium salts, and the ammonium salts).
  • salts preferably the alkali metal salts, e.g. the sodium or potassium salts, and the ammonium salts.
  • Examples are 2-acrylamido-2-methylpropanesulfonic acid, 2-acryloxyethanesulfonic acid, 2-methacryloxyethanesulfonic acid, 3-acryloxy- and 3-methacryloxypropanesulfonic acid, acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid.
  • Suitable ionic acrylates which comprise an cationic group are acrylates or methacrylates exhibiting at least one cationic group and/or at least one group which can be protonated in the aqueous medium, preferably a quaternary ammonium group, a protonatable amino group or a quaternized imino group.
  • Examples are 2-(N,N-dimethylamino)ethyl acrylate, 2-(N,N-dimethyla- mino)ethyl methacrylate, 2-(N,N-dimethylamino)ethylacrylamide, 3-(N,N-dimethylamino)propy- lacrylamide, 3-(N,N-dimeihylamino)propylmethacrylamide, 2-(N,N-dimethylamino)ethylmethac- rylamide, 2-(N,N,N-trimethylammonio)ethyl acrylate chloride, 2-(N,N,N-trimethylammonio)ethyl methacrylate chloride, 2-(N,N,N-trimethylammonio)ethylmethacrylamide chloride, 3-(N,N,N-tri- methylammonio)propylacrylamide chloride, 3-(N,N,N-trimethylammonio)propylacrylamide chloride
  • Preferred ionic acrylates are are 2-(N,N-dimethylamino)ethyl acrylate, 2- (N,N-dimethylamino)ethyl methacrylate, 2-(N,N-dimethylamino)ethylacrylamide, 3-(N,N-dime- thylamino)propylacrylamide, 3-(N,N-dimethylamino)propylmethacrylamide, 2-(N,N-dimethyla- mino)ethylmethacrylamide.
  • Suitable acrylate crossiinkers are difunctional or polyfunctional (meth)acrylate, wherein the polyfunctional (meth)acrylates are preferred.
  • Suitable difunctional (meth)acrylate are the diesters of diols with acrylic acid or methacrylic acid. Mention may be made, by way of example, of ethanediol diacrylate, ethylene glycol dimethacry- late, 1 ,3-butylene glycol dimethacrylate. Particular preference is given to propanediol, 1 ,4-bu- tanediol, pentanediol, and hexanediol diacrylates and the corresponding methacrylates.
  • Suitalbe polyfunctional (meth)acrylate are the polyesters of polyols with acrylic acid and/or methacrylic acid. Particular preference is given to trimethylolpropane triacrylate and trimethacry- late, pentaerythritol triacrylate, and pentaerythritol tetraacrylate, and also their technical mixtures.
  • the molar ratio of the alkyl(meth)acrylate to the ionic acrylte is usually from 1 :5 to 5:1 , preferably from 1 :3 to 3:1 , and in particular from 1 :2 to 2:1.
  • the copolymer may comprise from 15 to 45 wt%, preferably from 20 to 40 wt%, and in particular from 25 to 35 wt% of the a Iky I (meth)acrylate, based on the weight of all monomers present in the copolymer. Usually, the amount of all monomers present in the copolymer sums up to 100 wt%.
  • the copolymer may comprise from 30 to 65 wt%, preferably from 38 to 60 wt%, and in particular from 43 to 52 wt% of the ionic acrylate, based on the weight of all monomers present in the copolymer.
  • the copolymer may comprise up to 40 wt%, preferably up to 33 wt%, and in particular up to 28 wt% of the acrylate crosslinker, based on the weight of all monomers present in the copolymer.
  • the copolymer may comprise from 10 to 40 wt%, preferably from 12 to 33 wt%, and in particular from 18 to 28 wt% of the acrylate crosslinker, based on the weight of all monomers present in the copolymer.
  • the copolymer may comprise from 15 to 45 wt% of the alkyl (meth)acrylate; from 30 to 65 wt% of the ionic acrylate; and optionally comprise up to 40 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
  • the copolymer may comprise from 20 to 40 wt% of the alkyl (meth)acrylate; from 38 to 60 wt% of the ionic acrylate; and optionally comprise up to 33 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
  • the copolymer may comprise from 25 to 35 wt% of the alkyl (meth)acrylate; from 43 to 52 wt% of the ionic acrylate; and optionally comprise up to 28 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
  • the weight ratio of the pesticide particles to the copolymer is usually from 1 :1 to 50:1 , preferably from 1 ,5:1 to 35:1 , and in particular from 2:1 to 25:1 .
  • the pesticide particles usually comprise a pesticide in pure form or technical quality.
  • the pesticide may be water-insoluble.
  • the water-insoluble pesticide may have a solubility in water of up to 10 g/l, preferably up to 1 g/l, and in particular up to 0,1 g/l at 20 °C at pH 7.
  • the pesticide may have a melting point of at least 40 °C, preferably of at least 60 °C, and in particular of at least 80 C.
  • the pesticide particles comprise a pesticide which has a solubility in water of up to 10 g/l and a melting point of at least 40 C.
  • pesticide usually refers to at least one active substance selected from the group of the fungicides, insecticides, nematicides, herbicides, safeners, biopesticides and/or growth regulators.
  • Preferred pesticides are fungicides, insecticides, herbicides and growth regulators.
  • Espe- cially preferred pesticides are herbicides. Mixtures of pesticides of two or more of the above- mentioned classes may also be used. The skilled worker is familiar with such pesticides, which can be found, for example, in the Pesticide Manual, 17th Ed. (2015), The British Crop Protection Council, London.
  • Suitable insecticides are insecticides from the class of the carbamates, organ- ophosphates, organochlorine insecticides, phenylpyrazoles, pyrethroids, neonicotinoids, spi- nosins, avermectins, milbemycins, juvenile hormone analogs, alkyl halides, organotin compounds nereistoxin analogs, benzoylureas, diacylhydrazines, METI acarizides, and insecticides such as chloropicrin, pymetrozin, flonicamid, clofentezin, hexythiazox, etoxazole, diafenthiuron, propargite, tetrad if on, chlorofenapyr, DNOC, buprofezine, cyromazine, amitraz, hydramethyl- non, acequinocyl, fluacrypyrim, rotenone, or their derivatives.
  • Suitable fungicides are fungicides from the classes of dinitroanilines, allylamines, anilinopyrimidines, antibiotics, aromatic hydrocarbons, benzenesulfonamides, benzimidazoles, benzisothiazoles, benzophenones, benzothi- adiazoles, benzotriazines, benzyl carbamates, carbamates, carboxamides, carboxylic acid dia- mides, chloronitriles cyanoacetamide oximes, cyanoimidazoles, cyclopropanecarboxamides, di- carboximides, dihydrodioxazines, dinitrophenyl crotonates, dithiocarbamates, dithiolanes, ethylphosphonates, ethylaminothiazolecarboxamides, guanidines, hydroxy-(2-amino)pyrim- idines, hydroxyanilides, imidazoles, imi
  • Suitable herbicides are herbicides from the classes of the acetamides, amides, aryloxyphenoxypropionates, benzamides, benzofuran, benzoic acids, benzothiadiazinones, bi- pyridylium, carbamates, chloroacetamides, chlorocarboxylic acids, cyclohexanediones, di- nitroanilines, dinitrophenol, diphenyl ether, glycines, imidazolinones, isoxazoles, isoxazoli- dinones, nitriles, N-phenylphthalimides, oxadiazoles, oxazolidinediones, oxyacetamides, phe- noxycarboxylic acids, phenylcarbamates, phenylpyrazoles, phenylpyrazolines, phenylpyri- dazines, phosphinic acids, phosphoroamidates, phospho
  • the domain particles according to the invention can furthermore converted into customary types of agrochemical compositions, e. g. solutions, emulsions, suspensions, dusts, powders, pastes, granules, pressings, capsules, and mixtures thereof.
  • agrochemical compositions e.g. solutions, emulsions, suspensions, dusts, powders, pastes, granules, pressings, capsules, and mixtures thereof.
  • composition types are suspensions (e.g. SC, OD, FS), emulsifiable concentrates (e.g. EC), emulsions (e.g. EW, EO, ES, ME), capsules (e.g. CS, ZC), pastes, pastilles, wettable powders or dusts (e.g. WP, SP, WS, DP, DS), pressings (e.g.
  • compositions types are defined in the "Catalogue of pesticide formulation types and international coding system", Technical Monograph No. 2, 6 th Ed. May 2008, CropLife International.
  • compositions are prepared in a known manner, such as described by Mollet and Grube- mann, Formulation technology, Wiley VCH, Weinheim, 2001 ; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005.
  • the agrochemical compositions generally comprise between 0.01 and 95%, preferably between 0.1 and 90%, and most preferably between 0.5 and 75%, by weight of pesticide.
  • the active substances are employed in a purity of from 90% to 100%, preferably from 95% to 100% (according to NMR spectrum).
  • the invention further relates to a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the domain particles or the domain particles obtainable by the process are allowed to act on the respective pests, their environment or the crop plants to be protected from the re- spective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.
  • the amounts of pesticide applied are, depending on the kind of effect desired, from 0.001 to 2 kg per ha, preferably from 0.005 to 2 kg per ha, more prefera- bly from 0.05 to 0.9 kg per ha, in particular from 0.1 to 0.75 kg per ha.
  • amounts of active substance of from 0.1 to 1000 g, preferably from 1 to 1000 g, more preferably from 1 to 100 g and most preferably from 5 to 100 g, per 100 kilogram of plant propagation material (preferably seed) are generally required.
  • the amount of active substance applied depends on the kind of application area and on the desired effect. Amounts customarily applied in the protection of materials are 0.001 g to 2 kg, preferably 0.005 g to 1 kg, of active substance per cubic meter of treated material.
  • oils, wetters, adjuvants, fertilizer, or micronutrients, and other pesticides may be added to the active substances or the compositions comprising them as premix or, if appropriate not until immediately prior to use (tank mix).
  • pesticides e.g. herbicides, insecticides, fungicides, growth regulators, safeners
  • These agents can be admixed with the compositions according to the invention in a weight ratio of 1 :100 to 100:1 , preferably 1 :10 to 10:1 .
  • the user applies the composition according to the invention usually from a predosage device, a knapsack sprayer, a spray tank, a spray plane, or an irrigation system.
  • the agrochemical composition is made up with water, buffer, and/or further auxiliaries to the desired application concentration and the ready-to-use spray liquor or the agrochemical composition according to the invention is thus obtained.
  • 20 to 2000 liters, preferably 50 to 400 liters, of the ready-to-use spray liquor are applied per hectare of agricultural useful area.
  • the invention further relates to a process for preparing an aqueous dispersion of the domain particles comprising the steps of
  • step a) wherein the milling of step a) is performed in the presence of at least a portion of the monomer mix;
  • step a) wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the milling of step a).
  • the milling of step a) is performed in the presence of at least a portion of the monomer mix and wherein the aqueous suspension is free of a defoamer.
  • free of defoamer may mean that the aqueous contains less than 0,1 wt%, preferably less than 0,01 wt% of the defoamer.
  • Typical defoamers are silicones.
  • the term "coarse particle” means that the particles of the pesticide are bigger than the particles usually contained in a suspension concentrate formulation, which means that the volume average diameter D50 of the particles of the pesticide generally exceeds 20 pm, and is in particular at least 30 pm or at least 50 pm and may range from 20 pm to 2000 pm, in particular in the range of 30 pm to 1000 pm or in the range of 50 pm to 500 pm.
  • the average particle diameter is the volume average particle diameter D50, i.e. 50 vol.-% of the particles have a diameter which is above the value cited and 50 vol.-% of the particles have a diameter which is below the value cited. Therefore, average particle diameters are also termed "volume median diameters". Such average particle diameters can be determined by dynamic light scattering (usually performed on diluted suspensions containing from 0.01 to 5% by weight of the pesticide).
  • the aqueous suspension may comprise at least one auxiliaries.
  • the auxiliaries may be added in any step, or before or after said steps a) and b).
  • suitable auxiliaries are solvents, surfactants, dispersants, emulsifiers, wetters, adjuvants, solubilizers, penetration enhancers, protective colloids, adhesion agents, thickeners, humectants, repellents, attractants, feeding stimulants, compatibilizers, bactericides, anti-freezing agents, colorants, tackifiers and binders.
  • Suitable solvents are organic solvents, such as mineral oil fractions of medium to high boiling point, e.g. kerosene, diesel oil; oils of vegetable or animal origin; aliphatic, cyclic and aromatic hydrocarbons, e. g. toluene, paraffin, tetrahydronaphthalene, alkylated naphthalenes; alcohols, e.g. ethanol, propanol, butanol, benzylalcohol, cyclohexanol; glycols; DMSO; ketones, e.g. cy- clohexanone; esters, e.g.
  • mineral oil fractions of medium to high boiling point e.g. kerosene, diesel oil
  • oils of vegetable or animal origin oils of vegetable or animal origin
  • aliphatic, cyclic and aromatic hydrocarbons e. g. toluene, paraffin, tetrahydronaphthalene, alkylated n
  • the aqueous composition comprises less than 20 wt%, preferably less than 10 wt%, and in particular less than 3 wt% solvents.
  • Suitable surfactants are surface-active compounds, such as anionic, cationic, nonionic and amphoteric surfactants, block polymers, polyelectrolytes, and mixtures thereof.
  • Such surfactants can be used as emusifier, dispersant, solubilizer, wetter, penetration enhancer, protective colloid, or adjuvant.
  • Examples of surfactants are listed in cCutcheon ' s, Vol.1 : Emulsifiers & De- tergents, McCutcheon ' s Directories, Glen Rock, USA, 2008 (International Ed. or North American Ed.).
  • Suitable anionic surfactants are alkali, alkaline earth or ammonium salts of sulfonates, sulfates, phosphates, carboxylates, and mixtures thereof.
  • sulfonates are alkylarylsulfonates, diphenylsulfonates, alpha-olefin sulfonates, lignine sulfonates, sulfonates of fatty acids and oils, sulfonates of ethoxylated alkylphenols, sulfonates of alkoxylated arylphenols, sulfonates of condensed naphthalenes, sulfonates of dodecyl- and tridecylbenzenes, sulfonates of naphthalenes and alkylnaphthalenes, sulfosuccinates or sulfosuccinamates.
  • Examples of sulfates are sulfates of fatty acids and oils, of ethoxylated alkylphenols, of alcohols, of ethoxylated alcohols, or of fatty acid esters.
  • Examples of phosphates are phosphate esters.
  • Examples of carboxylates are alkyl carboxylates, and carboxylated alcohol or alkylphenol ethoxylates.
  • Suitable nonionic surfactants are alkoxylates, N-subsituted fatty acid amides, amine oxides, esters, sugar-based surfactants, polymeric surfactants, and mixtures thereof.
  • alkox- ylates are compounds such as alcohols, alkylphenols, amines, amides, arylphenols, fatty acids or fatty acid esters which have been alkoxylated with 1 to 50 equivalents.
  • Ethylene oxide and/or propylene oxide may be employed for the alkoxylation, preferably ethylene oxide.
  • N-subsititued fatty acid amides are fatty acid glucamides or fatty acid alkanolamides.
  • esters are fatty acid esters, glycerol esters or monoglycerides.
  • sugar-based sur- facta nts are sorbitans, ethoxylated sorbitans, sucrose and glucose esters or alkylpolygluco- sides.
  • polymeric surfactants are home- or copolymers of vinylpyrrolidone, vinylal- cohols, or vinylacetate.
  • Suitable cationic surfactants are quaternary surfactants, for example quaternary ammonium compounds with one or two hydrophobic groups, or salts of long-chain primary amines.
  • Suitable amphoteric surfactants are alkylbetains and imidazolines.
  • Suitable block polymers are block polymers of the A-B or A-B-A type comprising blocks of polyethylene oxide and polypropylene oxide, or of the A-B-C type comprising alkanol, polyethylene oxide and polypropylene oxide.
  • Suitable polyelectrolytes are polyacids or polybases. Examples of polyacids are alkali salts of poly- acrylic acid or polyacid comb polymers. Examples of polybases are polyvinylamines or polyeth- yleneamines.
  • Suitable adjuvants are compounds, which have a negligible or even no pesticidal activity themselves, and which improve the biological performance of the compound I on the target.
  • Exam- pies are surfactants, mineral or vegetable oils, and other auxilaries. Further examples are listed by Knowles, Adjuvants and additives, Agrow Reports DS256, T&F Informa UK, 2006, chapter 5.
  • Suitable thickeners are polysaccharides (e.g. xanthan gum, carboxymethylcellulose), anorganic clays (organically modified or unmodified), polycarboxylates, and silicates.
  • Suitable bactericides are bronopol and isothiazolinone derivatives such as alkylisothiazolinones and benzisothiazolinones.
  • Suitable anti-freezing agents are ethylene glycol, propylene glycol, urea and glycerin.
  • Suitable colorants are pigments of low water solubility and water-sol- uble dyes.
  • examples are inorganic colorants (e.g. iron oxide, titan oxide, iron hexacyanoferrate) and organic colorants (e.g. alizarin-, azo- and phthalocyanine colorants).
  • Suitable tackifiers or binders are polyvinylpyrrolidons, polyvinylacetates, polyvinyl alcohols, pol- yacrylates, biological or synthetic waxes, and cellulose ethers.
  • the aqueous suspension may comprise a protective colloid.
  • Protective colloids suitable for the process of the invention are principally any water-soluble polymers which are known to stabilize suspensions of water-insoluble material. Suitable protective colloids may be anionic, non-ionic or cationic.
  • Anionic protective colloids are water-soluble polymers, which contain a plurality of anionic groups, such as carboxylate groups, sulfonate groups, phosphonate groups, sulfate groups and/or phosphate groups.
  • the anionic groups in these anionic polymers may be partially or fully neutralized.
  • Suitable counter ions are alkalimetal ions, such as sodium, potassium, earth alka- line ions such as magnesium or calcium, and ammonium.
  • anionic polymeric surfactants having a sulfonate group the anionic groups are preferably at least partly neutralized.
  • Suitable anionic protective colloids are e.g.
  • anionically modified, water-soluble polysaccharides such as carboxymethylcellulose, lignin based sulfonic acids, such as lignosulfonic acid, ethoxylated lignosulfonic acid or oxi- dized lignins,
  • arylsulfonic acid formaldehyde condensates and arylsulfonic acid formaldehyde urea condensates such as naphthalene sulfonic acid formaldehyde condensates, phenol sulfonic acid formaldehyde condensates, cresol sulfonic acid formaldehyde condensates etc., homo- and copolymers of ethylenically unsaturated monomers which frequently comprise at least 20% by weight, based on the total amount of the monomers, of at least one ethylenically unsaturated monomer which comprises at least one carboxy group, sulfonic acid group, and/or phosphonic acid group incorporated within the polymer, and salts of these, in particular the alkali metal salts and ammonium salts.
  • the sulfonic acid groups or phosphonic acid groups bonded to the main polymer chain are generally in the salt form, i.e. in the form of sulfonate groups, the phosphonic acid groups correspondingly being in the form of phosphonate groups.
  • the counterions are then typically alkali metal ions and alkaline earth metal ions, examples being sodium ions, and calcium ions, and ammonium ions (NH 4 + );
  • Suitable non-ionic protective colloids are e.g.
  • water-soluble starches, starch derivatives, and cellulose derivatives such as methylcellulose, hydroxypropylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, and also polyvinyl alcohols, inclusive of partially hydrolyzed polyvinyl acetate with a degree of hydrolysis which is preferably at least 40%, in particular at least 60%, polyacrylamide, polyvinylpyrrolidone, polyethylene glycols, graft polymers of vinyl acetate and/or vinyl propionate onto polyethylene glycols, and polyethylene glycols mono- or bilaterally end-group-capped with alkyl, carboxy, or amino groups.
  • the protective colloids are selected from anionic polymers having a plurality of sul- fate or sulfonate groups, and neutral polymers having a plurality of hydroxyl groups, such as polyvinyl alcohols, inclusive of partially hydrolyzed polyvinyl acetate with a degree of hydrolysis which is preferably at least 40%, in particular at least 60%.
  • the protective colloid is selected from homo- or copolymers made of i) at least one monoethylenically unsaturated monomer M1 having a sulfonic acid group, such as vinylsulfonic acid, allylsulfonic acid, styrene sulfonic acid, vinyltoluene sulfonic acid, (meth)acrylate monomers having a sulfonic acid group, such as 2-acryloxyethyl- sulfonic acid, 2-acryloxypropylsulfonic or 4-acryloxybutylsulfonic acid, and (meth)acryla- mide monomer having a sulfonic acid group, such as 2-acrylamidoethylsulfonic acid, 2- acrylamidopropylsulfonic acid or 2-acrylamido-2-methylpropane sulfonic acid
  • a sulfonic acid group such as vinylsulfonic acid, allylsulfonic acid, st
  • comonomers M2 different from monomers M1 , such as styrene, Ci-C 4 -alkylacrylates, C1-C4-alkylmethacrylat.es, acryla- mide, methacrylamide, acrylic acid, methacrylic acid, C1-Ci-alkylacrylat.es, d-Ci-alkyl- methacrylates.
  • monomers M1 such as styrene, Ci-C 4 -alkylacrylates, C1-C4-alkylmethacrylat.es, acryla- mide, methacrylamide, acrylic acid, methacrylic acid, C1-Ci-alkylacrylat.es, d-Ci-alkyl- methacrylates.
  • the aqueous suspension may comprise up to 60 wt%, preferably up to 45 wt%, and in particular up to 35 wt% of the protective colloid, based on the total weight of the pesticide particles and the monomer mix present in the aqueous suspension.
  • the aqueous suspension may comprise from 10 to 60 wt%, preferably from 20 to 40 wt%, and in particular from 25 to 35 wt% of the protective colloid, based on the total weight of the pesticide particles and the monomer mix present in the aqueous suspension.
  • the aqueous suspension comprises a dispersant which is a comb polymer comprising a C1-C12 alkyl (meth)acrylate, and a polyalkylene glycol (meth)acrylate in polymerized form.
  • the dispersant is a comb polymer comprising Ci-Ce alkyl (meth)acrylate, polyethylene glycol (meth)acrylate, and optionally vinylpyridine in polymerized form.
  • the polyalkylene glycol (meth)acrylate may have a polyalkylene glycol unit based on ethylene glycol and/or propylene glycol, and it may be terminated by a hydroxy group or d-Ce alkylether group.
  • the polyalkylene glycol unit is methyl terminated polyethylene glycol.
  • the molecular weight of the polyalkylene glycol unit may vary from 200 to 5000 g/mol.
  • the aqueous suspension may comprise up to 30 wt%, preferably up to 20 wt%, and in particular up to 15 wt% of the dispersant, based on the total weight of the pesticide particles present in the aqueous suspension.
  • the aqueous suspension may comprise from 1 to 30 wt%, preferably from 3 to 20 wt%, and in particular from 5 to 15 wt% of the dispersant, based on the total weight of the pesticide particles present in the aqueous suspension.
  • step a) the aqueous suspension is subjected to a milling in order to comminute the coarse particles.
  • comminution is performed such that less than 10 % by weight of the particles have a particle diameter of 40 pm or larger, i.e. the D90 value is at most 40 ⁇ , in particular at most 30 pm and especially at most 25 pm.
  • comminution is performed such that the volume average particle diameter D50 is at most 25 pm or lower, e.g. in the range of 0.5 to 25 pm, in particular in the range of 0.5 to 15 pm and especially in the range of 0.5 to 10 pm.
  • the comminution is performed at a temperature, which is below the melting point of the pesticide, in particular at a temperature which is at least 10 C, in particular at least 20 C below the melting point of the pesticide.
  • Step a) may be carried out by any physical comminution method suitable for achieving comminution of solid particles in an aqueous suspension, including wet grinding, but also application of ultrasound or high pressure homogenization.
  • comminution is achieved by applying mechanical comminution methods, i.e. by subjecting the suspension to strong shear forces by mechanical means in a suitable comminution device.
  • mechanical comminution methods are in particular wet grinding techniques, such as ball mills, stirred media mills, rotor-stator mills and the like. Suitable mechanical grinding methods and grinding devices are known and have been described e.g. in H. Mollet and A.
  • Step a) may be performed by using a single comminution device. However, it is also possible to combine two or more comminution devices in series.
  • step a) is carried out in a stirred media mill.
  • step a) is performed by agitating the suspension together with a media of hard particles, which are harder than the particles of the pesticide, such that the particles and the hard particles collide, and the particles are broken in these collisions.
  • the media of hard particles is also referred to as grinding media.
  • the grinding media is stirred in a closed or open milling chamber, preferably closed milling chamber.
  • the preferred method of stirring is by means of a stirrer comprising a rotating shaft.
  • the shaft may be provided with disks, arms, pins, or other grinding devices.
  • the stirred media mil! may be operated in a batch or continuous mode.
  • the stirred media mill may be operated in a vertical or horizontal position, the latter being preferred.
  • the stirred media mill is operated in a continuous mode in which the aqueous suspension is recirculated to the inlet of the mill.
  • Recirculation of the product can be driven by conventional means, such as by employ- ing a peristaltic pump.
  • the product is recirculated as quickly as possible to achieve a high number of turnovers.
  • the required residence time for achieving the desired fineness will depend on several factors, such as the energy impact, the hardness of the material, the design of the milling apparatus and other features of the milling process, mentioned above. However, a skilled person will be readily in the position to evaluate the required residence time by routine experiments.
  • Stirred media mills are operated at tip speeds in the range of 3 to 15 m/s. Preferably in the range of 8 to 12 m/s.
  • Suitable agitated media mills are commercially available, e.g. from Netzsch Feinmahltechnik, Willy A. Bachofen AG Maschinenfabrik and Buhler GmbH.
  • Suitable grinding media include metal beads and ceramic beads.
  • Suitable metal beads include beads of carbon steel and beads of stainless steel.
  • Preferred ceramic beads include beads of zirconium oxide, beads of yttrium or cerium stabilized zirconium oxide, beads of zirconium silicate, and beads of alumina.
  • the preferred grinding media for the purpose of the invention are beads of yttrium stabilized zirconium oxide.
  • the grinding media used for particle size reduction are preferably spherical.
  • the grinding media for the practice of the present invention preferably have an average size ranging from about 50 to 2000 microns (0.05 to 2.0 mm), more preferably from about 200 to 1000 microns (0.2 to 1.0 mm).
  • the grinding media load measured as a volume percent of the mill chamber volume is 60 to 90%, more preferably 70 to 85 %.
  • step a) is performed in the absence of monomer mix, and the mono- mer mix is added after finishing the milling of step a). Accordingly, this may mean to perform steps a) and b) successively. If steps a) and b) are performed successively, one will perform step a) first, until the desired particle size of the pesticide is achieved, and then perform step b) by effecting the radical polymerization. In a preferred form the milling of step a) is performed in the presence of at least a portion of the monomer mix. Accordingly, this may mean to combine steps a) and b), i.e. to perform the radical polymerization while still comminuting the coarse particles.
  • step a) and b) are combined in a single step, the radical polymerization is performed while still performing comminution. It is not necessary to start polycondensation together with comminution. Rather, one will preferably start with step a) and continue step a) while starting the radical polymerization of step b).
  • the slurry of step a) is subjected to step b) until a certain fineness of the particles in the suspension is achieved and then radical polymerization is started, while still further performing means for comminuting the particles.
  • the domain particles can be isolated from the aqueous suspension obtained in step b), e.g.
  • the aqueous suspension may comprise buffers to regulate the pH.
  • buffers are alkali metal salts of weak inorganic or organic acids such as, for example, phosphoric acid, boric acid, acetic acid, propionic acid, citric acid, fumaric acid, tartaric acid, oxalic acid and succinic acid.
  • the advantages of the invention are the aqueous suspension of the domain particles have a high storage stability; that the process for preparing the domain particles may be done without defoamer; that the milling and polymerization can be done in one step and/or in one apparatus.
  • the examples which follow illustrate the invention without imposing any limitation.
  • Protective Colloid A Aqueous dispersion containing about 20% polymer based on 2- acrylamido-2-methylpropane sulfonic acid.
  • Dispersant A Aqueous solution containing about 50% of a comb polymer dispersant based on butyl methacrylate, methyl(polyethylene glycol) acrylate and vinylpyridine, prepared according to Example A6 of WO2006/074969.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume.
  • 188 g saflufenacil was mixed with 580 g water, 54 g Protective Colloid A, 16 g Dispersant A, 3,0 g methyl methacrylate (MMA), 2,2 g trime- thylolpropane trimethacrylate (TMPTMA), and 4,7 g ⁇ , ⁇ -dimethylaminoethyl methacrylate
  • the suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm.
  • 1 ,3 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 C.
  • 4,2 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
  • the obtained aqueous suspension of the domain particles had a D50 value of 7 pm and D90 of 1 1 pm.
  • the particle size was determined by light diffraction with a Malvern Mastersizer 2000.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume.
  • 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g MA, 4,0 g TMPTMA, and 8,3 g DMAEMA in a stirred vessel until a homogenous suspension was obtained.
  • the above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume.
  • 125 g saflufenacil was mixed with 474 g water, 48 g Protective Colloid A, 15 g Dispersant A, 10,5 g MMA, 7,9 g TMPTMA, and 16,6 g
  • DMAEMA in a stirred vessel until a homogenous suspension was obtained.
  • the above slurry was subjected to milling.
  • the mill was operated at a tip speed that averaged 12 m/s.
  • the sus- pension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm.
  • the suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm.
  • 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C.
  • 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
  • the obtained aqueous suspension of the domain particles had a D50 value of 1 1 pm and D90 of 52 pm.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g ethyl acrylate (EA), 4 g TMPTMA, and 8,3 g DMAEMA in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm.
  • the suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm.
  • 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C.
  • 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
  • the obtained aqueous suspension of the domain particles had a D50 value of 6 pm and D90 of 9 pm.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 6,5 g butyl acrylate (BA), 4 g TMPTMA, and 8,3 g DMAE A in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode.
  • a stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g MMA, 4 g TMPTMA, and 9 g dimethyla- minopropyl methacrylamide (DMAPMAM) in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode.
  • DMAPMAM dimethyla- minopropyl methacrylamide
  • the obtained aqueous suspension of the domain particles had a D50 value of 6 pm and D90 of 13 pm.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Pest Control & Pesticides (AREA)
  • Agronomy & Crop Science (AREA)
  • Plant Pathology (AREA)
  • Toxicology (AREA)
  • Engineering & Computer Science (AREA)
  • Dentistry (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Environmental Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)

Abstract

Domain particles of pesticide particles embedded in an ionic acrylate copolymer The present invention relates to domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising alkyl (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form; and to a process for preparing an aqueous dispersion of the domain particles comprising the steps of a) providing an aqueous suspension of a pesticide in form of coarse particles and subjecting the aqueous suspension to a mill- ing in order to comminute the coarse particles; and b) performing a radical polymerization of a monomer mix comprising an alkyl(meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in the aqueous suspension; wherein the milling of step a) is performed in the presence of at least a portion of the monomer mix; or wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the milling of step a); and it relates to a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the domain particles are allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.

Description

Domain particles of pesticide particles embedded in an ionic acrylate copolymer
The present invention relates to domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising alkyl (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form; and to a process for preparing an aqueous dispersion of the domain particles comprising the steps of a) providing an aqueous suspension of a pesticide in form of coarse particles and subjecting the aqueous suspension to a milling in order to comminute the coarse particles; and b) performing a radical polymerization of a monomer mix comprising an alkyl(meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in the aqueous suspension; wherein the milling of step a) is performed in the presence of at least a portion of the monomer mix; or wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the milling of step a); and it relates to a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the domain particles are allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment. The present invention comprises combinations of preferred features with other preferred features. The development of improved agrochemical formulations of pesticides, especially of pesticide particles, is an ongoing challenge.
The problem was solved by domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising alkyl (meth)acrylate, a water-soluble ionic acrylate, and option- ally an acrylate crosslinker in polymerized form.
The domain particles usually have an asymmetric form. The domain particles usually have a form which is distinct from a sphere. Typically, the surface of the domain particles has a plurality of indentations, which have a depth of at least 10 % (preferably at least 15%, and in particular at least 20%) of the average diameter D50 of the domain particle. The depth of the indentations may be measured under a microscope. During the preparation, e.g. during the polymerization step b) the pesticide particles often agglomerate resulting in domain particles. The domain particles usually contain a plurality of pesticide particles, which are at least partially coated with the copolymer.
The domain particles may have an average diameter D50 from 1 to 20 pm, preferably from 3 to 15 pm, and in particular from 5 to 12 pm. The domain particles may have an average diameter D90 from 3 to 90 pm, preferably from 5 to 75 pm, and in particular from 7 to 60 pm. The domain particle size may be determined by light scattering. The domain particle size may be determined directly after the preparation of the domain particles. The term "plurality of pesticide particles" means usually that at least two (preferably at least three) pesticide particles are present in a domain particle. A domain particle may comprise up to 100 pesticide particles, preferably up to 50.
The pesticide particles may have an average diameter D50 from 0,5 to 10 pm, preferably from 0,7 to 4 pm, and in particular from 0,8 to 2 pm. The pesticide particles may have an average diameter D90 from 1 to 12 pm, preferably from 2 to 8 pm, and in particular from 3 to 5 pm. The pesticide particle size may be determined by light scattering. The pesticide particle size may be determined directly after the milling of the coarse patricles.
The term "embedded in a copolymer" usually refers to pesticide particles, which are at least partially in direct contact with the copolymer. A typical example of such embedded pesticide particles is shown in Figure 1. Preferably, a majority of the pesticide particles are covered by the co- polymer. Generally, the copolymer forms a homogenous phase, in which the plurality of pesticide particles is embedded.
The copolymer comprises alkyi (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form. The copolymer may comprise further monomers. Usu- ally, the copolymer is a random copolymer.
The alkyi (meth)acrylate is typically Ci-Ce alkyi acrylate or Ci-Ce alkyi methacrylate, and preferably C1-C4 alkyi acrylate or C1-C4 alkyi methacrylate, and in particular methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, or butyl methacrylate. Mixtures of alkyi (meth)acry- late are also suitable. The term "(meth)acrylate" refers to acrylate and/or methacrylate.
The ionic acrylate may have a solubility in water of at least 5 g/l, preferably at least 10 g/l, and in particular at least 20 g/l, each at 20 °C. Suitable ionic acrylates are acrylates or methacrylates which comprise at least one anionic group (e.g. an acid group) or cationic group, wherein cationic groups are preferred.
Suitable ionic acrylates which comprise an anionic group are acrylates or methacrylates exhibiting a sulfonic acid group, a phosphonic acid group or one or two carboxylic acid groups, and their salts (preferably the alkali metal salts, e.g. the sodium or potassium salts, and the ammonium salts). Examples are 2-acrylamido-2-methylpropanesulfonic acid, 2-acryloxyethanesulfonic acid, 2-methacryloxyethanesulfonic acid, 3-acryloxy- and 3-methacryloxypropanesulfonic acid, acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid. Suitable ionic acrylates which comprise an cationic group are acrylates or methacrylates exhibiting at least one cationic group and/or at least one group which can be protonated in the aqueous medium, preferably a quaternary ammonium group, a protonatable amino group or a quaternized imino group. Examples are 2-(N,N-dimethylamino)ethyl acrylate, 2-(N,N-dimethyla- mino)ethyl methacrylate, 2-(N,N-dimethylamino)ethylacrylamide, 3-(N,N-dimethylamino)propy- lacrylamide, 3-(N,N-dimeihylamino)propylmethacrylamide, 2-(N,N-dimethylamino)ethylmethac- rylamide, 2-(N,N,N-trimethylammonio)ethyl acrylate chloride, 2-(N,N,N-trimethylammonio)ethyl methacrylate chloride, 2-(N,N,N-trimethylammonio)ethylmethacrylamide chloride, 3-(N,N,N-tri- methylammonio)propylacrylamide chloride, 3-(N,N,N-trimethylammonio)propylethacrylamide chloride, 2-(N,N,N-trimethylammonio)ethylacrylamide chloride, and the corresponding sulfates and methyl sulfates. Preferred ionic acrylates are are 2-(N,N-dimethylamino)ethyl acrylate, 2- (N,N-dimethylamino)ethyl methacrylate, 2-(N,N-dimethylamino)ethylacrylamide, 3-(N,N-dime- thylamino)propylacrylamide, 3-(N,N-dimethylamino)propylmethacrylamide, 2-(N,N-dimethyla- mino)ethylmethacrylamide.
Suitable acrylate crossiinkers are difunctional or polyfunctional (meth)acrylate, wherein the polyfunctional (meth)acrylates are preferred.
Suitable difunctional (meth)acrylate are the diesters of diols with acrylic acid or methacrylic acid. Mention may be made, by way of example, of ethanediol diacrylate, ethylene glycol dimethacry- late, 1 ,3-butylene glycol dimethacrylate. Particular preference is given to propanediol, 1 ,4-bu- tanediol, pentanediol, and hexanediol diacrylates and the corresponding methacrylates.
Suitalbe polyfunctional (meth)acrylate are the polyesters of polyols with acrylic acid and/or methacrylic acid. Particular preference is given to trimethylolpropane triacrylate and trimethacry- late, pentaerythritol triacrylate, and pentaerythritol tetraacrylate, and also their technical mixtures.
The molar ratio of the alkyl(meth)acrylate to the ionic acrylte is usually from 1 :5 to 5:1 , preferably from 1 :3 to 3:1 , and in particular from 1 :2 to 2:1.
The copolymer may comprise from 15 to 45 wt%, preferably from 20 to 40 wt%, and in particular from 25 to 35 wt% of the a Iky I (meth)acrylate, based on the weight of all monomers present in the copolymer. Usually, the amount of all monomers present in the copolymer sums up to 100 wt%.
The copolymer may comprise from 30 to 65 wt%, preferably from 38 to 60 wt%, and in particular from 43 to 52 wt% of the ionic acrylate, based on the weight of all monomers present in the copolymer.
The copolymer may comprise up to 40 wt%, preferably up to 33 wt%, and in particular up to 28 wt% of the acrylate crosslinker, based on the weight of all monomers present in the copolymer. In another form the copolymer may comprise from 10 to 40 wt%, preferably from 12 to 33 wt%, and in particular from 18 to 28 wt% of the acrylate crosslinker, based on the weight of all monomers present in the copolymer. The copolymer may comprise from 15 to 45 wt% of the alkyl (meth)acrylate; from 30 to 65 wt% of the ionic acrylate; and optionally comprise up to 40 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
The copolymer may comprise from 20 to 40 wt% of the alkyl (meth)acrylate; from 38 to 60 wt% of the ionic acrylate; and optionally comprise up to 33 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
The copolymer may comprise from 25 to 35 wt% of the alkyl (meth)acrylate; from 43 to 52 wt% of the ionic acrylate; and optionally comprise up to 28 wt% of the acrylate crosslinker; each based on the weight of all monomers present in the copolymer, and wherein the amount of all monomers present in the copolymer sums up to 100 wt%.
The weight ratio of the pesticide particles to the copolymer is usually from 1 :1 to 50:1 , preferably from 1 ,5:1 to 35:1 , and in particular from 2:1 to 25:1 . The pesticide particles usually comprise a pesticide in pure form or technical quality. The pesticide may be water-insoluble. The water-insoluble pesticide may have a solubility in water of up to 10 g/l, preferably up to 1 g/l, and in particular up to 0,1 g/l at 20 °C at pH 7. The pesticide may have a melting point of at least 40 °C, preferably of at least 60 °C, and in particular of at least 80 C. Preferably, the pesticide particles comprise a pesticide which has a solubility in water of up to 10 g/l and a melting point of at least 40 C.
The term pesticide usually refers to at least one active substance selected from the group of the fungicides, insecticides, nematicides, herbicides, safeners, biopesticides and/or growth regulators. Preferred pesticides are fungicides, insecticides, herbicides and growth regulators. Espe- cially preferred pesticides are herbicides. Mixtures of pesticides of two or more of the above- mentioned classes may also be used. The skilled worker is familiar with such pesticides, which can be found, for example, in the Pesticide Manual, 17th Ed. (2015), The British Crop Protection Council, London. Suitable insecticides are insecticides from the class of the carbamates, organ- ophosphates, organochlorine insecticides, phenylpyrazoles, pyrethroids, neonicotinoids, spi- nosins, avermectins, milbemycins, juvenile hormone analogs, alkyl halides, organotin compounds nereistoxin analogs, benzoylureas, diacylhydrazines, METI acarizides, and insecticides such as chloropicrin, pymetrozin, flonicamid, clofentezin, hexythiazox, etoxazole, diafenthiuron, propargite, tetrad if on, chlorofenapyr, DNOC, buprofezine, cyromazine, amitraz, hydramethyl- non, acequinocyl, fluacrypyrim, rotenone, or their derivatives. Suitable fungicides are fungicides from the classes of dinitroanilines, allylamines, anilinopyrimidines, antibiotics, aromatic hydrocarbons, benzenesulfonamides, benzimidazoles, benzisothiazoles, benzophenones, benzothi- adiazoles, benzotriazines, benzyl carbamates, carbamates, carboxamides, carboxylic acid dia- mides, chloronitriles cyanoacetamide oximes, cyanoimidazoles, cyclopropanecarboxamides, di- carboximides, dihydrodioxazines, dinitrophenyl crotonates, dithiocarbamates, dithiolanes, ethylphosphonates, ethylaminothiazolecarboxamides, guanidines, hydroxy-(2-amino)pyrim- idines, hydroxyanilides, imidazoles, imidazolinones, inorganic substances, isobenzofuranones, methoxyacrylates, methoxycarbamates, morpholines, N-phenylcarbamates, oxazolidinediones, oximinoacetates, oximinoacetamides, peptidylpyrimidine nucleosides, phenylacetamides, phe- nylamides, phenylpyrroles, phenylureas, phosphonates, phosphorothiolates, phthalamic acids, phthalimides, piperazines, piperidines, propionamides, pyridazinones, pyridines, pyridinylme- thylbenzamides, pyrimidinamines, pyrimidines, pyrimidinonehydrazones, pyrroloquinolinones, quinazolinones, quinolines, quinones, sulfamides, sulfamoyltriazoles, thiazolecarboxamides, thi- ocarbamates, thiophanates, thiophenecarboxamides, toluamides, triphenyltin compounds, tria- zines, triazoles. Suitable herbicides are herbicides from the classes of the acetamides, amides, aryloxyphenoxypropionates, benzamides, benzofuran, benzoic acids, benzothiadiazinones, bi- pyridylium, carbamates, chloroacetamides, chlorocarboxylic acids, cyclohexanediones, di- nitroanilines, dinitrophenol, diphenyl ether, glycines, imidazolinones, isoxazoles, isoxazoli- dinones, nitriles, N-phenylphthalimides, oxadiazoles, oxazolidinediones, oxyacetamides, phe- noxycarboxylic acids, phenylcarbamates, phenylpyrazoles, phenylpyrazolines, phenylpyri- dazines, phosphinic acids, phosphoroamidates, phosphorodithioates, phthalamates, pyrazoles, pyridazinones, pyridines, pyridinecarboxylic acids, pyridinecarboxamides, pyrimidinediones, py- rimidinyl(thio)benzoates, quinolinecarboxylic acids, semicarbazones, sulfonylaminocarbonyltria- zolinones, sulfonylureas, tetrazolinones, thiadiazoles, thiocarbamates, triazines, triazinones, triazoles, triazolinones, triazolocarboxamides, triazolopyrimidines, triketones, uracils, ureas. The domain particles according to the invention can furthermore converted into customary types of agrochemical compositions, e. g. solutions, emulsions, suspensions, dusts, powders, pastes, granules, pressings, capsules, and mixtures thereof. Examples for composition types are suspensions (e.g. SC, OD, FS), emulsifiable concentrates (e.g. EC), emulsions (e.g. EW, EO, ES, ME), capsules (e.g. CS, ZC), pastes, pastilles, wettable powders or dusts (e.g. WP, SP, WS, DP, DS), pressings (e.g. BR, TB, DT), granules (e.g. WG, SG, GR, FG, GG, MG), insecticidal articles (e.g. LN), as well as gel formulations for the treatment of plant propagation materials such as seeds (e.g. GF). These and further compositions types are defined in the "Catalogue of pesticide formulation types and international coding system", Technical Monograph No. 2, 6th Ed. May 2008, CropLife International.
The compositions are prepared in a known manner, such as described by Mollet and Grube- mann, Formulation technology, Wiley VCH, Weinheim, 2001 ; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005. The agrochemical compositions generally comprise between 0.01 and 95%, preferably between 0.1 and 90%, and most preferably between 0.5 and 75%, by weight of pesticide. The active substances are employed in a purity of from 90% to 100%, preferably from 95% to 100% (according to NMR spectrum).
The invention further relates to a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the domain particles or the domain particles obtainable by the process are allowed to act on the respective pests, their environment or the crop plants to be protected from the re- spective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.
When employed in plant protection, the amounts of pesticide applied are, depending on the kind of effect desired, from 0.001 to 2 kg per ha, preferably from 0.005 to 2 kg per ha, more prefera- bly from 0.05 to 0.9 kg per ha, in particular from 0.1 to 0.75 kg per ha. In treatment of plant propagation materials such as seeds, e. g. by dusting, coating or drenching seed, amounts of active substance of from 0.1 to 1000 g, preferably from 1 to 1000 g, more preferably from 1 to 100 g and most preferably from 5 to 100 g, per 100 kilogram of plant propagation material (preferably seed) are generally required. When used in the protection of materials or stored prod- ucts, the amount of active substance applied depends on the kind of application area and on the desired effect. Amounts customarily applied in the protection of materials are 0.001 g to 2 kg, preferably 0.005 g to 1 kg, of active substance per cubic meter of treated material.
Various types of oils, wetters, adjuvants, fertilizer, or micronutrients, and other pesticides (e.g. herbicides, insecticides, fungicides, growth regulators, safeners) may be added to the active substances or the compositions comprising them as premix or, if appropriate not until immediately prior to use (tank mix). These agents can be admixed with the compositions according to the invention in a weight ratio of 1 :100 to 100:1 , preferably 1 :10 to 10:1 . The user applies the composition according to the invention usually from a predosage device, a knapsack sprayer, a spray tank, a spray plane, or an irrigation system. Usually, the agrochemical composition is made up with water, buffer, and/or further auxiliaries to the desired application concentration and the ready-to-use spray liquor or the agrochemical composition according to the invention is thus obtained. Usually, 20 to 2000 liters, preferably 50 to 400 liters, of the ready-to-use spray liquor are applied per hectare of agricultural useful area.
The invention further relates to a process for preparing an aqueous dispersion of the domain particles comprising the steps of
a) providing an aqueous suspension of the pesticide in form of coarse particles and subjecting the aqueous suspension to a milling in order to comminute the coarse particles; b) performing a radical polymerization of a monomer mix comprising the alkyl(meth)acrylate, the water-soluble ionic acrylate, and optionally the acrylate crosslinker in the aqueous suspension;
wherein the milling of step a) is performed in the presence of at least a portion of the monomer mix; or
wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the milling of step a).
In a preferred form of the process the milling of step a) is performed in the presence of at least a portion of the monomer mix and wherein the aqueous suspension is free of a defoamer. The term "free of defoamer" may mean that the aqueous contains less than 0,1 wt%, preferably less than 0,01 wt% of the defoamer. Typical defoamers are silicones.
The term "coarse particle" means that the particles of the pesticide are bigger than the particles usually contained in a suspension concentrate formulation, which means that the volume average diameter D50 of the particles of the pesticide generally exceeds 20 pm, and is in particular at least 30 pm or at least 50 pm and may range from 20 pm to 2000 pm, in particular in the range of 30 pm to 1000 pm or in the range of 50 pm to 500 pm. The average particle diameter, as referred herein, is the volume average particle diameter D50, i.e. 50 vol.-% of the particles have a diameter which is above the value cited and 50 vol.-% of the particles have a diameter which is below the value cited. Therefore, average particle diameters are also termed "volume median diameters". Such average particle diameters can be determined by dynamic light scattering (usually performed on diluted suspensions containing from 0.01 to 5% by weight of the pesticide).
The aqueous suspension may comprise at least one auxiliaries. The auxiliaries may be added in any step, or before or after said steps a) and b). Examples for suitable auxiliaries are solvents, surfactants, dispersants, emulsifiers, wetters, adjuvants, solubilizers, penetration enhancers, protective colloids, adhesion agents, thickeners, humectants, repellents, attractants, feeding stimulants, compatibilizers, bactericides, anti-freezing agents, colorants, tackifiers and binders.
Suitable solvents are organic solvents, such as mineral oil fractions of medium to high boiling point, e.g. kerosene, diesel oil; oils of vegetable or animal origin; aliphatic, cyclic and aromatic hydrocarbons, e. g. toluene, paraffin, tetrahydronaphthalene, alkylated naphthalenes; alcohols, e.g. ethanol, propanol, butanol, benzylalcohol, cyclohexanol; glycols; DMSO; ketones, e.g. cy- clohexanone; esters, e.g. lactates, carbonates, fatty acid esters, gamma-butyrolactone; fatty acids; phosphonates; amines; amides, e.g. N-methylpyrrolidone, fatty acid dimethylamides; and mixtures thereof. Usually, the aqueous composition comprises less than 20 wt%, preferably less than 10 wt%, and in particular less than 3 wt% solvents. Suitable surfactants are surface-active compounds, such as anionic, cationic, nonionic and amphoteric surfactants, block polymers, polyelectrolytes, and mixtures thereof. Such surfactants can be used as emusifier, dispersant, solubilizer, wetter, penetration enhancer, protective colloid, or adjuvant. Examples of surfactants are listed in cCutcheon's, Vol.1 : Emulsifiers & De- tergents, McCutcheon's Directories, Glen Rock, USA, 2008 (International Ed. or North American Ed.).
Suitable anionic surfactants are alkali, alkaline earth or ammonium salts of sulfonates, sulfates, phosphates, carboxylates, and mixtures thereof. Examples of sulfonates are alkylarylsulfonates, diphenylsulfonates, alpha-olefin sulfonates, lignine sulfonates, sulfonates of fatty acids and oils, sulfonates of ethoxylated alkylphenols, sulfonates of alkoxylated arylphenols, sulfonates of condensed naphthalenes, sulfonates of dodecyl- and tridecylbenzenes, sulfonates of naphthalenes and alkylnaphthalenes, sulfosuccinates or sulfosuccinamates. Examples of sulfates are sulfates of fatty acids and oils, of ethoxylated alkylphenols, of alcohols, of ethoxylated alcohols, or of fatty acid esters. Examples of phosphates are phosphate esters. Examples of carboxylates are alkyl carboxylates, and carboxylated alcohol or alkylphenol ethoxylates.
Suitable nonionic surfactants are alkoxylates, N-subsituted fatty acid amides, amine oxides, esters, sugar-based surfactants, polymeric surfactants, and mixtures thereof. Examples of alkox- ylates are compounds such as alcohols, alkylphenols, amines, amides, arylphenols, fatty acids or fatty acid esters which have been alkoxylated with 1 to 50 equivalents. Ethylene oxide and/or propylene oxide may be employed for the alkoxylation, preferably ethylene oxide. Examples of N-subsititued fatty acid amides are fatty acid glucamides or fatty acid alkanolamides. Examples of esters are fatty acid esters, glycerol esters or monoglycerides. Examples of sugar-based sur- facta nts are sorbitans, ethoxylated sorbitans, sucrose and glucose esters or alkylpolygluco- sides. Examples of polymeric surfactants are home- or copolymers of vinylpyrrolidone, vinylal- cohols, or vinylacetate.
Suitable cationic surfactants are quaternary surfactants, for example quaternary ammonium compounds with one or two hydrophobic groups, or salts of long-chain primary amines. Suitable amphoteric surfactants are alkylbetains and imidazolines. Suitable block polymers are block polymers of the A-B or A-B-A type comprising blocks of polyethylene oxide and polypropylene oxide, or of the A-B-C type comprising alkanol, polyethylene oxide and polypropylene oxide. Suitable polyelectrolytes are polyacids or polybases. Examples of polyacids are alkali salts of poly- acrylic acid or polyacid comb polymers. Examples of polybases are polyvinylamines or polyeth- yleneamines.
Suitable adjuvants are compounds, which have a negligible or even no pesticidal activity themselves, and which improve the biological performance of the compound I on the target. Exam- pies are surfactants, mineral or vegetable oils, and other auxilaries. Further examples are listed by Knowles, Adjuvants and additives, Agrow Reports DS256, T&F Informa UK, 2006, chapter 5. Suitable thickeners are polysaccharides (e.g. xanthan gum, carboxymethylcellulose), anorganic clays (organically modified or unmodified), polycarboxylates, and silicates.
Suitable bactericides are bronopol and isothiazolinone derivatives such as alkylisothiazolinones and benzisothiazolinones.
Suitable anti-freezing agents are ethylene glycol, propylene glycol, urea and glycerin.
Suitable colorants (e.g. in red, blue, or green) are pigments of low water solubility and water-sol- uble dyes. Examples are inorganic colorants (e.g. iron oxide, titan oxide, iron hexacyanoferrate) and organic colorants (e.g. alizarin-, azo- and phthalocyanine colorants).
Suitable tackifiers or binders are polyvinylpyrrolidons, polyvinylacetates, polyvinyl alcohols, pol- yacrylates, biological or synthetic waxes, and cellulose ethers.
The aqueous suspension may comprise a protective colloid. Protective colloids suitable for the process of the invention are principally any water-soluble polymers which are known to stabilize suspensions of water-insoluble material. Suitable protective colloids may be anionic, non-ionic or cationic.
Anionic protective colloids are water-soluble polymers, which contain a plurality of anionic groups, such as carboxylate groups, sulfonate groups, phosphonate groups, sulfate groups and/or phosphate groups. The anionic groups in these anionic polymers may be partially or fully neutralized. Suitable counter ions are alkalimetal ions, such as sodium, potassium, earth alka- line ions such as magnesium or calcium, and ammonium. In case of anionic polymeric surfactants having a sulfonate group, the anionic groups are preferably at least partly neutralized. Suitable anionic protective colloids are e.g.
anionically modified, water-soluble polysaccharides such as carboxymethylcellulose, lignin based sulfonic acids, such as lignosulfonic acid, ethoxylated lignosulfonic acid or oxi- dized lignins,
arylsulfonic acid formaldehyde condensates and arylsulfonic acid formaldehyde urea condensates, such as naphthalene sulfonic acid formaldehyde condensates, phenol sulfonic acid formaldehyde condensates, cresol sulfonic acid formaldehyde condensates etc., homo- and copolymers of ethylenically unsaturated monomers which frequently comprise at least 20% by weight, based on the total amount of the monomers, of at least one ethylenically unsaturated monomer which comprises at least one carboxy group, sulfonic acid group, and/or phosphonic acid group incorporated within the polymer, and salts of these, in particular the alkali metal salts and ammonium salts. When the abovementioned anionic water-soluble polymers are in an aqueous medium, the sulfonic acid groups or phosphonic acid groups bonded to the main polymer chain are generally in the salt form, i.e. in the form of sulfonate groups, the phosphonic acid groups correspondingly being in the form of phosphonate groups. The counterions are then typically alkali metal ions and alkaline earth metal ions, examples being sodium ions, and calcium ions, and ammonium ions (NH4 +);
Non-ionic protective colloids are water-soluble polymers, which contain a plurality non-ionic polar moieties such as carbamoyl groups, i.e. 0(=0)ΝΙ-½ groups, lactam groups, such as pyrroli- din-2-on groups, polyethyleneoxide groups or hydroxy I groups. Suitable non-ionic protective colloids are e.g. water-soluble starches, starch derivatives, and cellulose derivatives, such as methylcellulose, hydroxypropylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, and also polyvinyl alcohols, inclusive of partially hydrolyzed polyvinyl acetate with a degree of hydrolysis which is preferably at least 40%, in particular at least 60%, polyacrylamide, polyvinylpyrrolidone, polyethylene glycols, graft polymers of vinyl acetate and/or vinyl propionate onto polyethylene glycols, and polyethylene glycols mono- or bilaterally end-group-capped with alkyl, carboxy, or amino groups.
Preferably, the protective colloids are selected from anionic polymers having a plurality of sul- fate or sulfonate groups, and neutral polymers having a plurality of hydroxyl groups, such as polyvinyl alcohols, inclusive of partially hydrolyzed polyvinyl acetate with a degree of hydrolysis which is preferably at least 40%, in particular at least 60%.
More preferably, the protective colloid is selected from homo- or copolymers made of i) at least one monoethylenically unsaturated monomer M1 having a sulfonic acid group, such as vinylsulfonic acid, allylsulfonic acid, styrene sulfonic acid, vinyltoluene sulfonic acid, (meth)acrylate monomers having a sulfonic acid group, such as 2-acryloxyethyl- sulfonic acid, 2-acryloxypropylsulfonic or 4-acryloxybutylsulfonic acid, and (meth)acryla- mide monomer having a sulfonic acid group, such as 2-acrylamidoethylsulfonic acid, 2- acrylamidopropylsulfonic acid or 2-acrylamido-2-methylpropane sulfonic acid
ii) optionally with one or more monoethylenically unsaturated comonomers M2 different from monomers M1 , such as styrene, Ci-C4-alkylacrylates, C1-C4-alkylmethacrylat.es, acryla- mide, methacrylamide, acrylic acid, methacrylic acid, C1-Ci-alkylacrylat.es, d-Ci-alkyl- methacrylates.
The aqueous suspension may comprise up to 60 wt%, preferably up to 45 wt%, and in particular up to 35 wt% of the protective colloid, based on the total weight of the pesticide particles and the monomer mix present in the aqueous suspension. In another form the aqueous suspension may comprise from 10 to 60 wt%, preferably from 20 to 40 wt%, and in particular from 25 to 35 wt% of the protective colloid, based on the total weight of the pesticide particles and the monomer mix present in the aqueous suspension.
Usually, the aqueous suspension comprises a dispersant which is a comb polymer comprising a C1-C12 alkyl (meth)acrylate, and a polyalkylene glycol (meth)acrylate in polymerized form. Pref- erably, the dispersant is a comb polymer comprising Ci-Ce alkyl (meth)acrylate, polyethylene glycol (meth)acrylate, and optionally vinylpyridine in polymerized form. The polyalkylene glycol (meth)acrylate may have a polyalkylene glycol unit based on ethylene glycol and/or propylene glycol, and it may be terminated by a hydroxy group or d-Ce alkylether group. For example the polyalkylene glycol unit is methyl terminated polyethylene glycol. The molecular weight of the polyalkylene glycol unit may vary from 200 to 5000 g/mol. The aqueous suspension may comprise up to 30 wt%, preferably up to 20 wt%, and in particular up to 15 wt% of the dispersant, based on the total weight of the pesticide particles present in the aqueous suspension. On another form the aqueous suspension may comprise from 1 to 30 wt%, preferably from 3 to 20 wt%, and in particular from 5 to 15 wt% of the dispersant, based on the total weight of the pesticide particles present in the aqueous suspension.
In step a) the aqueous suspension is subjected to a milling in order to comminute the coarse particles. Usually, comminution is performed such that less than 10 % by weight of the particles have a particle diameter of 40 pm or larger, i.e. the D90 value is at most 40 μιτι, in particular at most 30 pm and especially at most 25 pm. Preferably, comminution is performed such that the volume average particle diameter D50 is at most 25 pm or lower, e.g. in the range of 0.5 to 25 pm, in particular in the range of 0.5 to 15 pm and especially in the range of 0.5 to 10 pm.
Preferably, the comminution is performed at a temperature, which is below the melting point of the pesticide, in particular at a temperature which is at least 10 C, in particular at least 20 C below the melting point of the pesticide.
Step a) may be carried out by any physical comminution method suitable for achieving comminution of solid particles in an aqueous suspension, including wet grinding, but also application of ultrasound or high pressure homogenization. Preferably, comminution is achieved by applying mechanical comminution methods, i.e. by subjecting the suspension to strong shear forces by mechanical means in a suitable comminution device. Suitable mechanical comminution methods are in particular wet grinding techniques, such as ball mills, stirred media mills, rotor-stator mills and the like. Suitable mechanical grinding methods and grinding devices are known and have been described e.g. in H. Mollet and A. Grubenmann, Formulation Technology, Wiley VCH 2001 , Chapter 5.3.2 (Survey of Wet Grinding Mills) pp. 136 - 142 and the literature cited therein. Step a) may be performed by using a single comminution device. However, it is also possible to combine two or more comminution devices in series.
In particular embodiments of the invention, step a) is carried out in a stirred media mill. In other words, step a) is performed by agitating the suspension together with a media of hard particles, which are harder than the particles of the pesticide, such that the particles and the hard particles collide, and the particles are broken in these collisions. The media of hard particles is also referred to as grinding media. In the stirred media mill, the grinding media is stirred in a closed or open milling chamber, preferably closed milling chamber. The preferred method of stirring is by means of a stirrer comprising a rotating shaft. The shaft may be provided with disks, arms, pins, or other grinding devices. The stirred media mil! may be operated in a batch or continuous mode. The stirred media mill may be operated in a vertical or horizontal position, the latter being preferred. Preferably, the stirred media mill is operated in a continuous mode in which the aqueous suspension is recirculated to the inlet of the mill. Recirculation of the product can be driven by conventional means, such as by employ- ing a peristaltic pump. Preferably, the product is recirculated as quickly as possible to achieve a high number of turnovers. The required residence time for achieving the desired fineness will depend on several factors, such as the energy impact, the hardness of the material, the design of the milling apparatus and other features of the milling process, mentioned above. However, a skilled person will be readily in the position to evaluate the required residence time by routine experiments. Stirred media mills are operated at tip speeds in the range of 3 to 15 m/s. Preferably in the range of 8 to 12 m/s. Suitable agitated media mills are commercially available, e.g. from Netzsch Feinmahltechnik, Willy A. Bachofen AG Maschinenfabrik and Buhler GmbH.
Suitable grinding media include metal beads and ceramic beads. Suitable metal beads include beads of carbon steel and beads of stainless steel. Preferred ceramic beads include beads of zirconium oxide, beads of yttrium or cerium stabilized zirconium oxide, beads of zirconium silicate, and beads of alumina. The preferred grinding media for the purpose of the invention are beads of yttrium stabilized zirconium oxide. The grinding media used for particle size reduction are preferably spherical. The grinding media for the practice of the present invention preferably have an average size ranging from about 50 to 2000 microns (0.05 to 2.0 mm), more preferably from about 200 to 1000 microns (0.2 to 1.0 mm). Preferably the grinding media load measured as a volume percent of the mill chamber volume is 60 to 90%, more preferably 70 to 85 %.
In one form the milling of step a) is performed in the absence of monomer mix, and the mono- mer mix is added after finishing the milling of step a). Accordingly, this may mean to perform steps a) and b) successively. If steps a) and b) are performed successively, one will perform step a) first, until the desired particle size of the pesticide is achieved, and then perform step b) by effecting the radical polymerization. In a preferred form the milling of step a) is performed in the presence of at least a portion of the monomer mix. Accordingly, this may mean to combine steps a) and b), i.e. to perform the radical polymerization while still comminuting the coarse particles. If steps a) and b) are combined in a single step, the radical polymerization is performed while still performing comminution. It is not necessary to start polycondensation together with comminution. Rather, one will preferably start with step a) and continue step a) while starting the radical polymerization of step b). In particular, the slurry of step a) is subjected to step b) until a certain fineness of the particles in the suspension is achieved and then radical polymerization is started, while still further performing means for comminuting the particles. The domain particles can be isolated from the aqueous suspension obtained in step b), e.g. by filtration or centrifugation, or the aqueous suspension may be spray-dried, granulated or freeze- dried, to obtain a solid composition in the form of a powder or granules. The solid composition may be re-dispersed or formulated by using auxiliaries. If appropriate, the aqueous suspension may comprise buffers to regulate the pH. Examples of buffers are alkali metal salts of weak inorganic or organic acids such as, for example, phosphoric acid, boric acid, acetic acid, propionic acid, citric acid, fumaric acid, tartaric acid, oxalic acid and succinic acid.
The advantages of the invention are the aqueous suspension of the domain particles have a high storage stability; that the process for preparing the domain particles may be done without defoamer; that the milling and polymerization can be done in one step and/or in one apparatus. The examples which follow illustrate the invention without imposing any limitation.
Examples
Protective Colloid A: Aqueous dispersion containing about 20% polymer based on 2- acrylamido-2-methylpropane sulfonic acid.
Dispersant A: Aqueous solution containing about 50% of a comb polymer dispersant based on butyl methacrylate, methyl(polyethylene glycol) acrylate and vinylpyridine, prepared according to Example A6 of WO2006/074969.
Example 1
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume. 188 g saflufenacil was mixed with 580 g water, 54 g Protective Colloid A, 16 g Dispersant A, 3,0 g methyl methacrylate (MMA), 2,2 g trime- thylolpropane trimethacrylate (TMPTMA), and 4,7 g Ν,Ν-dimethylaminoethyl methacrylate
(DMAEMA) in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm.
The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,3 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 C. Finally, 4,2 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
The obtained aqueous suspension of the domain particles had a D50 value of 7 pm and D90 of 1 1 pm. The particle size was determined by light diffraction with a Malvern Mastersizer 2000. Example 2
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume. 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g MA, 4,0 g TMPTMA, and 8,3 g DMAEMA in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm. The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C. Finally, 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C. The obtained aqueous suspension of the domain particles had a D50 value of 8 pm and D90 of
43 pm.
Example 3
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume. 125 g saflufenacil was mixed with 474 g water, 48 g Protective Colloid A, 15 g Dispersant A, 10,5 g MMA, 7,9 g TMPTMA, and 16,6 g
DMAEMA in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The sus- pension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm.
The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C. Finally, 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
The obtained aqueous suspension of the domain particles had a D50 value of 1 1 pm and D90 of 52 pm.
Example 4
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g ethyl acrylate (EA), 4 g TMPTMA, and 8,3 g DMAEMA in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm.
The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C. Finally, 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 °C.
The obtained aqueous suspension of the domain particles had a D50 value of 6 pm and D90 of 9 pm.
Example 5
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 6,5 g butyl acrylate (BA), 4 g TMPTMA, and 8,3 g DMAE A in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm. The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 C. Finally, 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 "C. The obtained aqueous suspension of the domain particles had a D50 value of 6 pm and D90 of 12 pm.
Example 6
A stirred media mill was filled with zircon oxide grinding media with a diameter of 0.6 to 0.8 mm. Filling degree was 62.5 % of the internal volume., 143 g saflufenacil was mixed with 459 g water, 48 g Protective Colloid A, 15 g Dispersant A, 5,3 g MMA, 4 g TMPTMA, and 9 g dimethyla- minopropyl methacrylamide (DMAPMAM) in a stirred vessel until a homogenous suspension was obtained. The above slurry was subjected to milling. The mill was operated at a tip speed that averaged 12 m/s. The suspension was passed through the mill by circuit mode. After 2 hours of grinding the average particle size, by volume d(0.5), was reduced to 1 pm and 90 % of the particles had sizes of less than 4 pm. The suspension was transferred into a reaction vessel equipped with a stirrer and 1 ,2 g of 2,5% sodium nitrite and redispersed for 30 min at 350 rpm. Next, 1 ,2 g tert-butylperpivalate was added under stirring, and heated for 3,5 h to 60-85 °C. Finally, 4,1 g of 10% aqueous tert-bu- tylhydroperoxide was added and 0,2 g ascorbic acid in 18 g water while stirring for 1 h at 85 C.
The obtained aqueous suspension of the domain particles had a D50 value of 6 pm and D90 of 13 pm.

Claims

Claims
Domain particles comprising a plurality of pesticide particles embedded in a copolymer comprising a Iky I (meth)acrylate, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in polymerized form.
The domain particles according to claim 1 which have an asymmetric form.
The domain particles according to claim 1 or 2 wherein the surface of the domain particles has a plurality of indentations, which have a depth of at least 10 % of the average diameter
D50 of the domain particle.
4. The domain particles according to any of claims 1 to 3 which have an average diameter D50 from 3 to 20 pm, preferably from 4 to 15 pm, and in particular from 5 to 12 pm.
5. The domain particles according to any of claims 1 to 4 wherein the weight ratio of the pesticide particles to the copolymer is from 1 :1 to 50:1.
6. The domain particles according to any of claims 1 to 5 wherein the ionic acrylate has a sol- ubility in water of at least 5 g/l, preferably at least 10 g/l.
7. The domain particles according to any of claims 1 to 6 wherein the ionic acrylate comprises 2-(N,N-dimethylamino)ethyl acrylate, 2-(N,N-dimethylamino)ethyl methacrylate, 2-(N,N-di- methylamino)ethylacrylamide, 3-(N,N-dimethylamino)propylacrylamide, 3-(N,N-dimethyla- mino)propylmethacrylamide, 2-(N,N-dimethylamino)ethylmethacrylamide, 2-(N,N,N-trime- thylammonio)ethyl acrylate chloride, 2-(N,N,N-trimethylammonio)ethyl methacrylate chloride, 2-(N,N,N-trimethylammonio)ethylmethacrylamide chloride, 3-(N,N,N-trimethyl- ammonio)propylacrylamide chloride, 3-(N,N,N-trimethylammonio)propylethacrylamide chloride, 2-(N,N,N-trimethylammonio)ethylacrylamide chloride, and the corresponding sulfates and methyl sulfates.
8. The domain particles according to any of claims 1 to 7 wherein the alkyl(meth)acrylate is Ci-Ce alkyl acrylate or Ci-Ce alkyl methacrylate. 9. The domain particles according to any of claims 1 to 8 wherein the acrylate crosslinker are diesters of diols with acrylic acid or methacrylic acid, or polyesters of polyols with acrylic acid and/or meth-acrylic acid.
10. The domain particles according to any of claims 1 to 9 wherein the molar ratio of the al- kyl(meth)acrylate to the ionic acrylate is from 1 :5 to 5:1 , preferably from 1 :3 to 3:1.
1 1. The domain particles according to any of claims 1 to 10 wherein the pesticide particles comprise a pesticide which has a solubility in water of up to 10 g/l and a melting point of at least 40 °C. 12. The domain particles according to any of claims 1 to 1 1 wherein he copolymer comprises from 15 to 45 wt%, preferably from 20 to 40 wt% of the a Iky I (meth)acrylate, based on the weight of all monomers present in the copolymer.
13. The domain particles according to any of claims 1 to 12 wherein the copolymer comprises from 30 to 65 wt%, preferably from 38 to 60 wt% of the ionic acrylate, based on the weight of all monomers present in the copolymer.
14. The domain particles according to any of claims 1 to 13 wherein the copolymer comprise from 10 to 40 wt%, preferably from 12 to 33 wt% of the acrylate crosslinker, based on the weight of all monomers present in the copolymer.
15. A process for preparing an aqueous dispersion of the domain particles as defined in any of claims 1 to 14 comprising the steps of
a) providing an aqueous suspension of a pesticide in form of coarse particles and subject- ing the aqueous suspension to a milling in order to comminute the coarse particles; and b) performing a radical polymerization of a monomer mix comprising an alkyl(meth)acry- late, a water-soluble ionic acrylate, and optionally an acrylate crosslinker in the aqueous suspension;
wherein the milling of step a) is performed in the presence of at least a portion of the mono- mer mix; or
wherein the milling of step a) is performed in the absence of monomer mix, and the monomer mix is added after finishing the milling of step a).
16. The process according to claim 15 wherein the milling of step a) is performed in the pres- ence of at least a portion of the monomer mix and wherein the aqueous suspension is free of a defoamer.
17. The process according to claim 15 or 16 wherein the aqueous suspension comprises a dis- persant which is a comb polymer comprising a C1-C12 alkyl (meth)acrylate, and a poly- alkylene glycol (meth)acrylate in polymerized form.
18. A method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the domain particles as defined in any of claims 1 to 14 or the domain particles obtainable by the pro- cess as defined in any of claims 15 to 17 are allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.
PCT/EP2016/076398 2015-12-01 2016-11-02 Domain particles of pesticide particles embedded in an ionic acrylate copolymer WO2017092951A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP15197180.1 2015-12-01
EP15197180 2015-12-01

Publications (1)

Publication Number Publication Date
WO2017092951A1 true WO2017092951A1 (en) 2017-06-08

Family

ID=54754549

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2016/076398 WO2017092951A1 (en) 2015-12-01 2016-11-02 Domain particles of pesticide particles embedded in an ionic acrylate copolymer

Country Status (1)

Country Link
WO (1) WO2017092951A1 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994016561A1 (en) * 1993-01-29 1994-08-04 E.I. Du Pont De Nemours And Company Agrichemical tablet formulations containing active material encapsulated in water-soluble polymers
WO2007072046A2 (en) * 2005-12-23 2007-06-28 Syngenta Limited. Formulation

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994016561A1 (en) * 1993-01-29 1994-08-04 E.I. Du Pont De Nemours And Company Agrichemical tablet formulations containing active material encapsulated in water-soluble polymers
WO2007072046A2 (en) * 2005-12-23 2007-06-28 Syngenta Limited. Formulation

Similar Documents

Publication Publication Date Title
EP3324738B1 (en) Agrochemical formulation with copolymers comprising hydroxybutylvinylether as an associative thickener
CN106068076B (en) Carbonates of alcohol alkoxylates as adjuvants for crop protection
EP3365102B1 (en) A process for preparing an aqueous dispersion of microparticles
EP2405743A1 (en) Composition comprising pesticide and benzotriazole uv absorbers
CA3015456A1 (en) Use of tetrazolinones for combating resistant phytopathogenic fungi on fruits
EP3258781B1 (en) Agrochemical granules made of polyalkoxylate, dispersant, sugar, and polyvinylpyrrolidone
EP2833718B1 (en) Method of preparation of granules by milling pesticide and silica, addition of adjuvant, and fluidized bed granulation
WO2017092951A1 (en) Domain particles of pesticide particles embedded in an ionic acrylate copolymer
EP3137535B1 (en) Mixed alkyl terminated polyether dendrons
US20110263422A1 (en) Aqueous dispersion comprising pesticide particles and an amphiphile
DK2833718T3 (en) PROCEDURE FOR THE PREPARATION OF GRANULATE BY PREPARING PESTICID AND SILICY ACID, ADDITION OF ADJUVANCES AND FLUID BED GRANULATION
WO2023017068A1 (en) Agrochemical composition
EP2381768B1 (en) Agrochemical compositions comprising branched alcooxyalkanoates
WO2018114409A1 (en) High load granular dinotefuran formulation with reduced eye irritancy
WO2017084946A1 (en) High-payload granules containing a sulfosuccinate surfactant and a polycarboxylic acid

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16790351

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16790351

Country of ref document: EP

Kind code of ref document: A1