The present invention is related to the area of agriculture and concerns new non-ionic sugar surfactants, a process for making them and their use as additives, in particular as adjuvants or formulation aids in plant and crop protection.
Alkoxylation products of sugar alcohols, for example sorbitol, have been known for a long time. These products are very well known as adjuvants and formulation aids for pesticides in crop and plant protection. Nevertheless, it is desirous to replace sugar alcohols by oligosaccharides, such as saccharose, since these raw materials are much cheaper and more readily available in the market. However, so far alkoxylation of oligosaccharides has proven difficult for the following reasons:
Therefore, the object of the present invention has been to provide alkoxylation products of oligosaccharides showing a decreased amount of polyglycolethers (PGE), in particular PGE-amounts of less than 5, preferably less than 2 and most preferably less than 1% b.w. and a process for obtaining them which avoids the disadvantages of the state of the art.
The present invention refers to alkylene oxide adducts of oligosaccharides, obtainable in that an aqueous solution of at least one water-soluble oligosaccharide is subjected to alkoxylation within a temperature range of 90 to 160° C.
Surprisingly it has been observed that conducting alkoxylation of oligosaccharides in the presence of water, in particular using saturated or nearly saturated aqueous solutions of said carbohydrates allows raising the temperature up to 160° C. without any or very little decomposition or discolouring of the starting material. At the same time the formation of unwanted polyglycolethers is reduced to amounts of less than 5, in most cases less than 1% b.w. Since the starting material is liquid alkoxylation can take place in standard equipments.
As second object of the present invention covers a process for making alkylene oxide adducts of oligosaccharides, which is characterised in that an aqueous solution of at least one water-soluble oligosaccharide is subjected to alkoxylation within a temperature range of 90 to 160° C.
Water-Soluble Oligosaccharides
Basically, the selection of oligosaccharides is not critical as long as they show at room temperature a sufficient solubility or at least dispersability in water. An oligosaccharide is considered to be water soluble when solubility is at least 100 g/L. Therefore the choice fully depends on the properties of the final alkoxylation product in the proposed application. Suitable candidates are disaccharides, trisaccharides and oligosaccharides having at least 4 and on average not more than 20 sugar units. The saccharides may represent oligoglucosides or oligofructo-side or even mixtures of both structures. Preferred examples are selected from the group comprising saccharose, maltose, and maltotriose. For economic reasons suitable candidates for alkoxylation can also be obtained by chemical or enzymatic degradation of polysaccharides like for example celluloses, starches or waste material from sugar industry. Also certain natural or synthetic gums or their degradation products, like for example xanthan gum are useful.
Although it is also possible to work with diluted solutions of said oligosaccharides it is for economic reasons more useful to prepare saturated aqueous solutions; also, with regard to the surprising effects associated with the present invention, solutions of about 300 g oligosaccharide in 100 ml water can be subjected to alkoxylation at temperatures of about 120° C. with no, or very little decomposition or caramelisation.
Alkylene Oxides
Alkoxylation can be conducted by adding ethylene oxide (EO), propylene oxide (PO) or their mixtures to the hydroxyl groups of the oligosaccharides. As a matter of fact alkoxylation is driven by statistics, meaning that adding, for example, 10 moles of ethylene oxide to saccharose will lead to a complex mixture of mono, di and tri-substituted adducts, each of them showing different degrees of ethoxylation. The alkoxylation may take place blockwise or randomised, so that it is possible to add first an amount of ethylene oxide and then propylene oxide to the hydroxyl groups in order to produce blocks of EO and PO units, or to use mixtures of both alkylene oxides in order to obtain a random sequence of EO and PO groups. On average about 1 to about 50, preferably about 5 to about 25 and more preferably about 10 to 20 mol alkylene oxide are added to each Mol of oligosaccharide. Preferred products are adducts of about 10 to 12 mol ethylene oxide to saccharose, maltose or maltotriose.
Alkoxylation Process
Basically alkoxylation is conducted in known manner which, for example, is also standard for the production of fatty alcohol polyglycolethers. The aqueous solutions containing the oligosaccharides along with the catalyst are placed into a pressure reactor. Suitable catalysts are alkaline bases, like sodium hydroxide, potassium hydroxide or sodium methylate, which are used in the form of concentrated or diluted aqueous or alcoholic solutions. Typically the catalysts are used in amounts of about 1 to about 5% b.w. calculated on the sum of starting materials. It has been found advantageous to conduct alkoxylation within a temperature interval of 90 to 160, preferably 100 to 140° C. and a pressure in between 1 and 5 bar. Once the addition of the alkylene oxide is completed it is advantageous to stir the product for another 30 minutes while maintaining the temperature. Subsequently, the reactor is cooled down, vacuum is broken and the catalyst is neutralised by adding an organic acid, such as for example lactic acid.
Another object of the present invention refers to the use of the new alkylene oxide adducts of oligosaccharides as additives in agriculture, in particular as adjuvants, tank-mix adjuvants or formulation aids for making plant and crop protection compositions.
Typically, the new alkylene oxide adducts are used together with biocides in ratios by weight—calculated on the active matter, that is, based on the total of adjuvant plus biocide—of about 1:99 to about 50:50, preferably about 10:80 to about 40:60. These compositions are also object of the present invention.
Biocides
A biocide is a chemical substance capable of killing different forms of living organisms used in fields such as medicine, agriculture, forestry, and mosquito control. Usually, biocides are divided into two sub-groups:
Biocides can also be added to other materials (typically liquids) to protect the material from biological infestation and growth. For example, certain types of quaternary ammonium compounds (quats) can be added to pool water or industrial water systems to act as an algicide, protecting the water from infestation and growth of algae. Suitable biocides which can be combined with the alkylene oxide adducts according to the present invention are described in the following. The present invention includes the observation that due to the low amount of unwanted by-products such as polyalkyleneglycol ethers, the new alkylene oxide adducts show an improved synergistic behavior when combined with said biocides, especially species like glyphosate, glufosinate, paraquat and their mixtures.
Pesticides
The U.S Environmental Protection Agency (EPA) defines a pesticide as “any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest”.[1] A pesticide may be a chemical substance or biological agent (such as a virus or bacteria) used against pests including insects, plant pathogens, weeds, mollusks, birds, mammals, fish, nematodes (roundworms) and microbes that compete with humans for food, destroy property, spread disease or are a nuisance. In the following examples, pesticides suitable for the agrochemical compositions according to the present invention are given:
Fungicides. A fungicide is one of three main methods of pest control—the chemical control of fungi in this case. Fungicides are chemical compounds used to prevent the spread of fungi in gardens and crops. Fungicides are also used to fight fungal infections. Fungicides can either be contact or systemic. A contact fungicide kills fungi when sprayed on its surface. A systemic fungicide has to be absorbed by the fungus before the fungus dies. Examples for suitable fungicides, according to the present invention, encompass the following species: (3-ethoxypropyl)mercury bromide, 2-methoxyethylmercury chloride, 2-phenylphenol, 8-hydroxyquinoline sulfate, 8-phenylmercurioxyquinoline, acibenzolar, acylamino acid fungicides, acypetacs, aldimorph, aliphatic nitrogen fungicides, allyl alcohol, amide fungicides, ampropylfos, anilazine, anilide fungicides, antibiotic fungicides, aromatic fungicides, aureofungin, azaconazole, azithiram, azoxystrobin, barium polysulfide, benalaxy,1 benalaxyl-M, benodanil, benomyl, benquinox, bentaluron, benthiavalicarb, benzalkonium chloride, benzamacril, benzamide fungicides, benzamorf, benzanilide fungicides, benzimidazole fungicides, benzimidazole precursor fungicides, benzimidazolylcarbamate fungicides, benzohydroxamic acid, benzothiazole fungicides, bethoxazin, binapacryl, biphenyl, bitertanol, bithionol, blasticidin-S, Bordeaux mixture, boscalid, bridged diphenyl fungicides, bromuconazole, bupirimate, Burgundy mixture, buthiobate, butylamine, calcium polysulfide, captafol, captan, carbamate fungicides, carbamorph, carbanilate fungicides, carbendazim, carboxin, carpropamid, carvone, Cheshunt mixture, chinomethionat, chlobenthiazone, chloraniformethan, chloranil, chlorfenazole, chlorodinitronaphthalene, chloroneb, chloropicrin, chlorothalonil, chlorquinox, chlozolinate, ciclopirox, climbazole, clotrimazole, conazole fungicides, conazole fungicides (imidazoles), conazole fungicides (triazoles), copper(II) acetate, copper(II) carbonate, basic, copper fungicides, copper hydroxide, copper naphthenate, copper oleate, copper oxychloride, copper(II) sulfate, copper sulfate, basic, copper zinc chromate, cresol, cufraneb, cuprobam, cuprous oxide, cyazofamid, cyclafuramid, cyclic dithiocarbamate fungicides, cycloheximide, cyflufenamid, cymoxanil, cypendazole, cyproconazole, cyprodinil, dazomet, DBCP, debacarb, decafentin, dehydroacetic acid, dicarboximide fungicides, dichlofluanid, dichlone, dichlorophen, dichlorophenyl, dicarboximide fungicides, dichlozoline, diclobutrazol, diclocymet, diclomezine, dicloran, diethofencarb, diethyl pyrocarbonate, difenoconazole, diflumetorim, dimethirimol, dimethomorph, dimoxystrobin, diniconazole, dinitrophenol fungicides, dinobuton, dinocap, dinocton, dinopenton, dinosulfon, dinoterbon, diphenylamine, dipyrithione, disulfuram, ditalimfos, dithianon, dithiocarbamate fungicides, DNOC, dodemorph, dodicin, dodine, donatodine, drazoxolon, edifenphos, epoxiconazole, etaconazole, etem, ethaboxam, ethirimol, ethoxyquin, ethylmercury 2,3-dihydroxypropyl mercaptide, ethylmercury acetate, ethylmercury bromide, ethylmercury chloride, ethylmercury phosphate, etridiazole, famoxadone, fenamidone, fenaminosulf, fenapanil, fenarimol, fenbuconazole, fenfuram, fenhexamid, fenitropan, fenoxanil, fenpiclonil, fenpropidin, fenpropimorph, fentin, ferbam, ferimzone, fluazinam, fludioxonil, flumetover, flumorph, fluopicolide, fluoroimide, fluotrimazole, fluoxastrobin, fluquinconazole, flusilazole, flusulfamide, flutolanil, flutriafol, folpet, formaldehyde, fosetyl, fuberidazole, furalaxyl, furametpyr, furamide fungicides, furanilide fungicides, furcarbanil, furconazole, furconazole-cis, furfural, furmecyclox, furophanate, glyodin, griseofulvin, guazatine, halacrinate, hexachlorobenzene, hexachlorobutadiene, hexachlorophene, hexaconazole, hexylthiofos, hydrargaphen, hymexazol, imazalil, imibenconazole, imidazole fungicides, iminoctadine, inorganic fungicides, inorganic mercury fungicides, iodomethane, ipconazole, iprobenfos, iprodione, iprovalicarb, isoprothiolane, isovaledione, kasugamycin, kresoxim-methyl, lime sulphur, mancopper, mancozeb, maneb, mebenil, mecarbinzid, mepanipyrim, mepronil, mercuric chloride, mercuric oxide, mercurous chloride, mercury fungicides, metalaxyl, metalaxyl-M, metam, metazoxolon, metconazole, methasulfocarb, methfuroxam, methyl bromide, methyl isothiocyanate, methylmercury benzoate, methylmercury dicyandiamide, methylmercury pentachlorophenoxide, metiram, metominostrobin, metrafenone, metsulfovax, milneb, morpholine fungicides, myclobutanil, myclozolin, N-(ethylmercury)-p-toluenesulphonanilide, nabam, natamycin, nitrostyrene, nitrothal-isopropyl, nuarimol, OCH, octhilinone, ofurace, organomercury fungicides, organophosphorus fungicides, organotin fungicides, orysastrobin, oxadixyl, oxathiin fungicides, oxazole fungicides, oxine copper, oxpoconazole, oxycarboxin, pefurazoate, penconazole, pencycuron, pentachlorophenol, penthiopyrad, phenylmercuriurea, phenylmercury acetate, phenylmercury chloride, phenylmercury derivative of pyrocatechol, phenylmercury nitrate, phenylmercury salicylate, phenylsulfamide fungicides, phosdiphen, phthalide, phthalimide fungicides, picoxystrobin, piperalin, polycarbamate, polymeric dithiocarbamate fungicides, polyoxins, polyoxorim, polysulfide fungicides, potassium azide, potassium polysulfide, potassium thiocyanate, probenazole, prochloraz, procymidone, propamocarb, propiconazole, propineb, proquinazid, prothiocarb, prothioconazole, pyracarbolid, pyraclostrobin, pyrazole fungicides, pyrazophos, pyridine fungicides, pyridinitril, pyrifenox, pyrimethanil, pyrimidine fungicides, pyroquilon, pyroxychlor, pyroxyfur, pyrrole fungicides, quinacetol, quinazamid, quinconazole, quinoline fungicides, quinone fungicides, quinoxaline fungicides, quinoxyfen, quintozene, rabenzazole, salicylanilide, silthiofam, simeconazole, sodium azide, sodium orthophenylphenoxide, sodium pentachlorophenoxide, sodium polysulfide, spiroxamine, streptomycin, strobilurin fungicides, sulfonanilide fungicides, sulfur, sultropen, TCMTB, tebuconazole, tecloftalam, tecnazene, tecoram, tetraconazole, thiabendazole, thiadifluor, thiazole fungicides, thicyofen, thifluzamide, thiocarbamate fungicides, thiochlorfenphim, thiomersal, thiophanate, thiophanate-methyl, thiophene fungicides, thioquinox, thiram, tiadinil, tioxymid, tivedo, tolclofos-methyl, tolnaftate, tolylfluanid, tolylmercury acetate, triadimefon, triadimenol, triamiphos, triarimol, triazbutil, triazine fungicides, triazole fungicides, triazoxide, tributyltin oxide, trichlamide, tricyclazole, tridemorph, trifloxystrobin, triflumizole, triforine, triticonazole, unclassified fungicides, undecylenic acid, uniconazole, urea fungicides, validamycin, valinamide fungicides, vinclozolin, zarilamid, zinc naphthenate, zineb, ziram, zoxamide and their mixtures.
Herbicides. An herbicide is a pesticide used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often based on plant hormones. Herbicides used to clear waste ground are nonselective and kill all plant material with which they come into contact. Herbicides are widely used in agriculture and in landscape turf management. They are applied in total vegetation control (TVC) programs for maintenance of highways and railroads. Smaller quantities are used in forestry, pasture systems, and management of areas set aside as wildlife habitat. In the following, a number of suitable herbicides are compiled:
Insecticides. An insecticide is a pesticide used against insects in all developmental forms. They include ovicides and larvicides used against the eggs and larvae of insects. Insecticides are used in agriculture, medicine, industry and the household. In the following, suitable insecticides are mentioned:
Rodenticides. Rodenticides are a category of pest control chemicals intended to kill rodents. Rodents are difficult to kill with poisons because their feeding habits reflect their place as scavengers. They would eat a small bit of something and wait, and if they do not get sick, they would continue eating. An effective rodenticide must be tasteless and odorless in lethal concentrations, and have a delayed effect. In the following, examples for suitable rodenticides are given:
Miticides, moluscicides and nematicides. Miticides are pesticides that kill mites. Antibiotic miticides, carbamate miticides, formamidine miticides, mite growth regulators, organochlorine, permethrin and organophosphate miticides all belong to this category. Molluscicides are pesticides used to control mollusks, such as moths, slugs and snails. These substances include metaldehyde, methiocarb and aluminium sulfate. A nematicide is a type of chemical pesticide used to kill parasitic nematodes (a phylum of worm). A nematicide is obtained from a neem tree's seed cake; which is the residue of neem seeds after oil extraction. The neem tree is known by several names in the world but was first cultivated in India since ancient times.
Antimicrobials. In the following examples, antimicrobials suitable for agrochemical compositions according to the present invention are given. Bactericidal disinfectants mostly used are those applying
Bactericidal antibiotics kill bacteria; bacteriostatic antibiotics only slow down their growth or reproduction. Penicillin is a bactericide, as are cephalosporins. Aminoglycosidic antibiotics can act in both a bactericidic manner (by disrupting cell wall precursor leading to lysis) or bacteriostatic manner (by connecting to 30 s ribosomal subunit and reducing translation fidelity leading to inaccurate protein synthesis). Other bactericidal antibiotics according to the present invention include the fluoroquinolones, nitrofurans, vancomycin, monobactams, co-trimoxazole, and metronidazole.
An aqueous solution of 572 g (1.67 Mol) saccharose in 181 ml water and 4 g of an aqueous potassium hydroxide solution (50% b.w.) were placed in a stirred autoclave. Once the reactor was three times evacuated and purged with nitrogen to remove all traces of oxygen, the mixture was heated to about 125° C. and within about 3.5 h 737 g (16.75 Mol) ethylene oxide was added, while the pressure raised to about 5.5 bar. Subsequently the mixture was left for another 30 min for post reaction, maintaining the temperature at about 130° C., Finally, the reactor was cooled down to room temperature, vacuum was broken and the pH of the products adjusted to about 7 by adding a lactic acid solution. The liquid thus obtained consisted of about 88% of Saccharose+10EO and about 12% water; the PGE content has been less than 1% b.w.
Table 1 reflects a number of herbicide compositions applicable according to instructions to use Monsanto's ROUND-UP, which are well known for those skilled in the art.
Number | Date | Country | Kind |
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07024713 | Dec 2007 | EP | regional |
This application is the National Phase entry of PCT/EP2008/010494, filed Dec. 11, 2008, which claims priority to European patent application number EP07024713, filed Dec. 20, 2007, all of which are incorporated herein by reference in their entireties.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP08/10494 | 12/11/2008 | WO | 00 | 6/21/2010 |