Patent Application
20140206541
The present invention belongs to the area of agriculture and refers to new biocide compositions comprising special types of optionally alkoxylated surfactants, with enhanced surface activity and electrolyte stability, in particular improved hard-water performance.
Biocides, and in particular pesticides such as fungicides, insecticides and herbicides, are important auxiliary agents for agriculture in order to protect and to increase crops. Depending on the various and often very specific needs, a magnitude of actives exist, which show very different chemical structures and behaviors.
Pesticide products may be formulated as liquids, powders, or granules. Solvents, emulsifiers, dispersing agents and wetting agents are normally incorporated into such compositions in order to ensure that a uniform pesticide formulation has been prepared. Successful employment of any pesticide depends upon its proper formulation into a preparation that can be easily diluted with water into ready-to-use mixtures for application onto a targeted pest and/or agricultural substrate. In addition, the market requires additives—so-called “adjuvants”—providing additional benefit to the formulation by increasing the performance of the biocides in a synergistic way.
Supply industry offers a wide spectrum of products, especially formulations, intending to fulfill all requirements of the end users. Of particular interest are surfactants working at the same time as adjuvants and solvents, wetting agents or emulsifiers. For example, FR 2758436 A1 discloses an adjuvant composition comprising fatty acid esters, terpene derivatives and emulsifiers. Preferably said esters are obtained from sun flower oil and comprise 1 to 11 carbon atoms in the ester moiety. The emulsifiers may represent non-ionic surfactants, literally cited are ethoxylated fatty acids. U.S. Pat. No. 6,432,884 (Cognis) also refers to adjuvant compositions comprising fatty acid alkyl esters, like for example oleic acid ethyl ester, and non-ionic surfactants, like for example sorbitan esters. International patent application WO 2004/080177 A1 (Cognis) discloses adjuvant compositions comprising fatty acid alkyl esters and a mixture of hydrophilic and hydrophobic emulsifiers. European patent EP 0765602 B1 (Kao) recommends ethoxylated esters of glycerol or polyglycerol as adjuvants for herbicides.
While a huge number of surfactants are well known for exhibiting excellent properties in water of low hardness, in high electrolyte solutions there is a very short list of effective and compatible surface active agents that also fulfill the needs for agrochemical industry explained above. Tallow amine ethoxylates and derivatives have been industry standard for many years. Today these products are objected due to eye irritation as well as impact to fish and the environment. In fact all ethoxylated surfactants carry residues of 1,4 dioxane which trigger special regulatory concerns, as for example Proposition 65 in California, USA.
Therefore, the problem underlying the present invention has been to provide new surface active agents, which are useful as adjuvants, solvents and emulsifiers not only in aqueous solutions of reduced water hardness, but also at high electrolyte concentrations of more than 100 ppm Ca2+ and Mg2+. It is also an aim of the present invention to provide new additives simultaneously overcoming the disadvantages of other well-known surfactants, which means that these products show a better surface activity and simultaneously exhibit a high compatibility with a variety of different biocides, especially with glyphosate, glufosinate and their salts.
Provided are agricultural compositions comprising:
(a) one or more esters of
Surprisingly, it has been observed that esters of said polyhydric alcohols, especially esters of oligo- or polyglycerols show superior properties with respect to wetting capacity and solubility of various biocides, especially glyphosate, in aqueous solutions having a content of Ca2+ and Mg2+ of up to 1,000 ppm.
More particular, the present invention has the advantage that it can be formulated with a high amount of ionic active ingredient, is thermally stable over a wide temperature range, is compatible with and dilutable in both hard and soft water, and is also compatible and dilutable with a nitrogeneous fertilizer solution, and is minimally irritable to the eyes. Also, formulations of this invention have proven stable upon aging over months of storage, over a wide temperature range. In addition, the non-ionic surfactants are derived from naturally occurring products and are readily broken down by microorganisms.
Esters of polyhydric alcohols, which form component (a) of the inventive compositions, are derived by reacting a source of a carboxylic acid and a source of a polyhydric alcohol in the presence of an acidic or alkaline catalyst and removing the water of condensation to shift the equilibrium of the reaction towards the target esters.
The esters according to the present invention are obtained from either mono- or dicarboxylic acids and polyhydric alcohols. In case monocarboxylic acids are used discrete molecules result containing one to three or even more ester groups, depending on the number of hydroxyl function that are available for esterification. In case dicarboxylic acids are reacted with polyhydric alcohols oligomers or even lower polymers are obtained, since esterification goes along with a crosslinking between the two polyfunctional reaction partners.
In a preferred embodiment compound (a) represents a mixture of mono, di- and triesters of C6-C22 monocarboxylic acids or C2-C22 dicarboxylic acids with glycerol, diglycerol, triglycerol, oligo- or polyglycerol or their statistical mixtures or esters derived from alkylene oxide adducts of said polyhydric alcohols, in particular of adducts of on average 1 to 100, preferably 2 to 50 and more preferably 5 to 25 moles ethylene oxide, propylene oxide and/or butylene oxide to said polyhydric alcohols.
With respect to the glycerols it should be noted that the phrase “oligoglycerol” means any statistical mixture that mainly consists of mono-, di-, triglycerol and higher condensation products up to a degree of oligomerisation of 10. On the other hand “polyglycerol” means any statistical mixture comprising also higher condensation products.
Typically, the monocarboxylic acids cover a chain length of 6 to 22, but preferably 6 to 12 and more preferably 8 to 10 carbon atoms. These acids may be linear or branched, saturated or unsaturated and optionally carrying a hydroxyl group. Typical examples for suitable monocarboxylic acids are the group of fatty acids comprising capronic acid, caprylic acid, caprinic acid, lauric acid, myristic acid, palmitic acid, palmoleic acid, stearic acid, isostearic acid, oleic acid, elaidinic acid, linoic acid, linolenic acid, 12-hydroxy stearic acid, ricinoleic acid, gadoleic acid, arachidonic acid, behenic acid, erucic acid and their technical mixtures, like for example coco fatty acid, palm fatty acid, tallow fatty acid, sunflower fatty acid, soy fatty acid and the like. Also suitable is benzoic acid.
Examples for suitable dicarboxylic acids encompass oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacinic acid, pelargonic acid, dodecandioc acid, but also aromatic species like phthalic acid, isophthalic acid or terephthalic acid. Among the dicarboxylic acids adipic acid is the preferred one.
With respect to their compatibility with hard water and their performance as solvents and adjuvants mono-, di-, and triesters of C6 to C10 fatty acid esters or adipic acid with oligo- or polyglycerols are preferred.
The esters of polyhydric alcohols forming group (a) are preferably essentially free of esters of monomeric glycerol or esters of adducts of alkylene oxide to monomeric glycerol. Essential free means that remaining amounts of these monomers is less than 0.5% b.w., preferably less than 0.4% b.w., more preferably less than 0.2% b.w. and most preferably less than 0.1% b.w.—calculated on the total amount of esters of polyhydric alcohol forming group (a).
Typically, esters of group (a), in particular fatty acid esters of polyglycerols are synthesized in a two-step process. Glycerol monomer is polymerized through alkaline catalyzed condensation or alternatively epichlorohydrin. The alkaline catalyzed condensation product is a mixture of isomers of increasing complexity with increasing degree of polymerization. On the other hand the use if epichlorohydrin produces only linear polymers. In every case, as the degree of polymerization increases, the residual glycerol monomer diminishes, however the state of the art has been to ignore unreacted monomer.
The second step is the esterification of an essentially neutral polyglycerol with selected fatty acids. Classically, 30-% to 50% of all available hydroxyl groups (on the polyglycerol) are substituted during the esterification step, having a mole ratio of polyglycerol derivative to fatty acid between 2:1 and 3:1. The residual monomer is the most readily esterified species, having a mole ratio of glycerol monomer to fatty acid between 1:1 and 1:4. These uncontrolled reaction mixtures typically yield products that are strong emulsifiers and dispersants with low electrolyte tolerance. Although these products find utility in cosmetic creams and gels and processed foods, their utility in wetting and high electrolyte applications is limited.
Alkoxylated polyglycerol fatty acid esters follow similar steps (as outlined above) with the glycerol polymerization, an added reaction with ethylene oxide and/or propylene oxide, and finally esterification with fatty acids. The primary application for this chemistry is defoamers.
However, the presence of glycerol monomer (or alkoxylated glycerol) during the esterification step increases the substitution of hydroxyl groups, increasing the lipophilic nature of the classical compositions. This invention refers to a composition essentially free of mono glycerol (or glycereth) esters by selectively removing unreacted glycerol monomer after the polymerization step is completed. The preferred method is to use vacuum to selectively distill glycerol monomer from the higher molecular weight oligo- and polyglycerols. It is common practice to induce low level vacuum (400-mmHg) to remove water during the condensation polymerization. By applying high vacuum (5-mmHg) to the reaction product, glycerol can be essentially eliminated from future reaction steps. This is the first step in creating electrolyte tolerant polyglycerol fatty acid esters. The second step is drastically reducing the amount of fatty acid added during esterification to yield a final product having a mole ratio of polyglycerol derivative to fatty acid between 12:1 and 20:1. The actual ratio will vary depending on degree of alkoxylation (of the polyglycerol) and the length of the fatty acid chain. The highest electrolyte tolerance was found with fatty acid chains from six to ten carbons in length. The most active wetting agents were found to be polyglycerol esters of lauric acid.
Therefore another embodiment of the present invention refers to a process for obtaining esters of polyhydric alcohols with improved surface activity and increased electrolytic stability, comprising the steps of:
A biocide (component b) in the context of the present invention is a plant protection agent, more particular a chemical substance capable of killing different forms of living organisms used in fields such as medicine, agriculture, forestry, and mosquito control. Also counted under the group of biocides are so-called plant growth regulators. 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.
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”. A pesticide may be a chemical substance or biological agent (such as a virus or bacteria) used against pests including insects, plant pathogens, weeds, molluscs, 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:
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 chemical classes and corresponding examples:
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 non-selective 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 general, active ingredients representing including various chemical classes and corresponding examples can be used
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 chemical classes and examples of insecticides are mentioned:
Plant hormones (also known as phytohormones) are chemicals that regulate plant growth. Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells locally and when moved to other locations, in other locations of the plant. Plants, unlike animals, lack glands that produce and secrete hormones. Plant hormones shape the plant, affecting seed growth, time of flowering, the sex of flowers, senescence of leaves and fruits. They affect which tissues grow upward and which grow downward, leaf formation and stem growth, fruit development and ripening, plant longevity and even plant death. Hormones are vital to plant growth and lacking them, plants would be mostly a mass of undifferentiated cells. In the following, suitable plant growth regulators are mentioned:
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:
Anticoagulants are defined as chronic (death occurs after 1-2 weeks post ingestion of the lethal dose, rarely sooner), single-dose (second generation) or multiple dose (first generation) cumulative rodenticides. Fatal internal bleeding is caused by lethal dose of anticoagulants such as brodifacoum, coumatetralyl or warfarin. These substances in effective doses are antivitamins K, blocking the enzymes K1-2,3-epoxide-reductase (this enzyme is preferentially blocked by 4-hydroxycoumarin/4-hydroxythiacoumarin derivatives) and K1-quinone-reductase (this enzyme is preferentially blocked by indandione derivatives), depriving the organism of its source of active vitamin K1. This leads to a disruption of the vitamin K cycle, resulting in an inability of production of essential blood-clotting factors (mainly coagulation factors II (prothrombin), VII (proconvertin), IX (Christmas factor) and X (Stuart factor)). In addition to this specific metabolic disruption, toxic doses of 4-hydroxycoumarin/4-hydroxythiacoumarin and indandione anticoagulants are causing damage to tiny blood vessels (capillaries), increasing their permeability, causing diffuse internal bleedings (haemorrhagias). These effects are gradual; they develop in the course of days and are not accompanied by any nociceptive perceptions, such as pain or agony. In the final phase of intoxication the exhausted rodent collapses in hypovolemic circulatory shock or severe anemia and dies calmly. Rodenticidal anticoagulants are either first generation agents (4-hydroxycoumarin type: warfarin, coumatetralyl; indandione type: pindone, diphacinone, chlorophacinone), generally requiring higher concentrations (usually between 0.005 and 0.1%), consecutive intake over days in order to accumulate the lethal dose, poor active or inactive after single feeding and less toxic than second generation agents, which are derivatives of 4-hydroxycoumarin (difenacoum, brodifacoum, bromadiolone and flocoumafen) or 4-hydroxy-1-benzothiin-2-one (4-hydroxy-1-thiacoumarin, sometimes incorrectly referred to as 4-hydroxy-1-thiocoumarin, for reason see heterocyclic compounds), namely difethialone. Second generation agents are far more toxic than first generation agents, they are generally applied in lower concentrations in baits (usually in the order of 0.001-0.005%), and are lethal after single ingestion of bait and are effective also against strains of rodents that have become resistant against first generation anticoagulants; thus the second generation anticoagulants are sometimes referred to as “superwarfarins”. Sometimes, anticoagulant rodenticides are potentiated by an antibiotic, most commonly by sulfaquinoxaline. The aim of this association (e.g. warfarin 0.05%+sulfaquinoxaline 0.02%, or difenacoum 0.005%+sulfaquinoxaline 0.02% etc.) is that the antibiotic/bacteriostatic agent suppresses intestinal/gut symbiotic microflora that represents a source of vitamin K. Thus the symbiotic bacteria are killed or their metabolism is impaired and the production of vitamin K by them is diminuted, an effect which logically contributes to the action of anticoagulants. Antibiotic agents other than sulfaquinoxaline may be used, for example co-trimoxazole, tetracycline, neomycin or metronidazole. A further synergism used in rodenticidal baits is that of an association of an anticoagulant with a compound with vitamin D-activity, i.e. cholecalciferol or ergocalciferol (see below). A typical formula used is, e.g., warfarin 0.025-0.05%+cholecalciferol 0.01%. In some countries there are even fixed three-component rodenticides, i.e. anticoagulant+antibiotic+vitamin D, e.g. difenacoum 0.005%+sulfaquinoxaline 0.02%+cholecalciferol 0.01%. Associations of a second-generation anticoagulant with an antibiotic and/or vitamin D are considered to be effective even against the most resistant strains of rodents, though some second generation anticoagulants (namely brodifacoum and difethialone), in bait concentrations of 0.0025-0.005% are so toxic that no known resistant strain of rodents exists and even rodents resistant against any other derivatives are reliably exterminated by application of these most toxic anticoagulants.
Vitamin K1 has been suggested and successfully used as an antidote for pets or humans, which/who were either accidentally or intentionally (poison assaults on pets, suicidal attempts) exposed to anticoagulant poisons. In addition, since some of these poisons act by inhibiting liver functions and in progressed stages of poisoning, several blood-clotting factors as well as the whole volume of circulating blood lacks, a blood transfusion (optionally with the clotting factors present) can save a person's life who inadvertently takes them, which is an advantage over some older poisons.
Metal phosphides have been used as a means of killing rodents and are considered single-dose fast acting rodenticides (death occurs commonly within 1-3 days after single bait ingestion). A bait consisting of food and a phosphide (usually zinc phosphide) is left where the rodents can eat it. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas. This method of vermin control has possible use in places where rodents are resistant to some of the anticoagulants, particularly for control of house and field mice; zinc phosphide baits are also cheaper than most second-generation anticoagulants, so that sometimes, in cases of large infestation by rodents, their population is initially reduced by copious amounts of zinc phosphide bait applied, and the rest of the population that survived the initial fast-acting poison is then eradicated by prolonged feeding on anticoagulant bait. Inversely, the individual rodents that survived anticoagulant bait poisoning (rest population) can be eradicated by pre-baiting them with nontoxic bait for a week or two (this is important to overcome bait shyness, and to get rodents used to feeding in specific areas by offering specific food, especially when eradicating rats) and subsequently applying poisoned bait of the same sort as used for pre-baiting until all consumption of the bait ceases (usually within 2-4 days). These methods of alternating rodenticides with different modes of action provides a factual or an almost 100% eradication of the rodent population in the area if the acceptance/palatability of bait is good (i.e., rodents readily feed on it).
Phosphides are rather fast acting rat poisons, resulting in that the rats are dying usually in open areas instead of the affected buildings. Typical examples are aluminum phosphide (fumigant only), calcium phosphide (fumigant only), magnesium phosphide (fumigant only) and zinc phosphide (in baits). Zinc phosphide is typically added to rodent baits in amounts of around 0.75-2%. The baits have a strong, pungent garlic-like odor characteristic for phosphine liberated by hydrolysis. The odor attracts (or, at least, does not repulse) rodents, but has a repulsive effect on other mammals; birds, however (notably wild turkeys), are not sensitive to the smell and feed on the bait thus becoming collateral damage.
Hypercalcemia. Calciferols (vitamins D), cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) are used as rodenticides, which are toxic to rodents for the same reason that they are beneficial to mammals: they are affecting calcium and phosphate homeostasis in the body. Vitamins D are essential in minute quantities (few IUs per kilogram body weight daily, which is only a fraction of a milligram), and like most fat soluble vitamins they are toxic in larger doses as they readily result in the so-called hypervitaminosis, which is, simply said, poisoning by the vitamin. If the poisoning is severe enough (that is, if the dose of the toxicant is high enough), it eventually leads to death. In rodents consuming the rodenticidal bait it causes hypercalcemia by raising the calcium level, mainly by increasing calcium absorption from food, mobilising bonematrix-fixed calcium into ionised form (mainly monohydrogencarbonate calcium cation, partially bound to plasma proteins, [CaHCO3]+), which circulates dissolved in the blood plasma, and after ingestion of a lethal dose the free calcium levels are raised sufficiently so that blood vessels, kidneys, the stomach wall and lungs are mineralised/calcificated (formation of calcificates, crystals of calcium salts/complexes in the tissues thus damaging them), leading further to heart problems (myocard is sensitive to variations of free calcium levels that are affecting both myocardial contractibility and excitation propagation between atrias and ventriculas) and bleeding (due to capillary damage) and possibly kidney failure. It is considered to be single-dose, or cumulative (depending on concentration used; the common 0.075% bait concentration is lethal to most rodents after a single intake of larger portions of the bait), sub-chronic (death occurring usually within days to one week after ingestion of the bait). Applied concentrations are 0.075% cholecalciferol and 0.1% ergocalciferol when used alone. There is an important feature of calciferols toxicology which is that they are synergistic with anticoagulant toxicants. This means that mixtures of anticoagulants and calciferols in the same bait are more toxic than the sum of toxicities of the anticoagulant and the calciferol in the bait so that a massive hypercalcemic effect can be achieved by substantially lower calciferol content in the bait and viceversa. More pronounced anticoagulant/hemorrhagic effects are observed if calciferol is present. This synergism is mostly used in baits low in calciferol because effective concentrations of calciferols are more expensive than effective concentrations of most anticoagulants. The historically very first application of a calciferol in rodenticidal bait was, in fact, the Sorex product Sorexa® D (with a different formula than today's Sorexa® D) back in the early 1970's, containing warfarin 0.025%+ergocalciferol 0.1%. Today, Sorexa® CD contains a 0.0025% difenacoum+0.075% cholecalciferol combination. Numerous other brand products containing either calciferols 0.075-0.1% (e.g. Quintox®, containing 0.075% cholecalciferol) alone, or a combination of calciferol 0.01-0.075% with an anticoagulant are marketed.
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.
In the following examples, antimicrobials suitable for agrochemical compositions according to the present invention are given. Bactericidal disinfectants mostly used are those applying
As antiseptics (i.e., germicide agents that can be used on human or animal body, skin, mucoses, wounds and the like), few of the above mentioned disinfectants can be used under proper conditions (mainly concentration, pH, temperature and toxicity toward man/animal). Among them, important are
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 30s 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 Preferred actives are those with systemic or partially systemic mode of action such as for example azoxystrobin.
Overall preferred are non-selective herbicides and in particular biocides selected either
Suitable oil components or co-solvents (component c) are, for example, Guerbet alcohols based on fatty alcohols having 6 to 18, preferably 8 to 10, carbon atoms, esters of linear C6-C22-fatty acids with linear or branched C6-C22-fatty alcohols or esters of branched C6-C13-carboxylic acids with linear or branched C6-C22-fatty alcohols, such as, for example, myristyl myristate, myristyl palmitate, myristyl stearate, myristyl isostearate, myristyl oleate, myristyl behenate, myristyl erucate, cetyl myristate, cetyl palmitate, cetyl stearate, cetyl isostearate, cetyl oleate, cetyl behenate, cetyl erucate, stearyl myristate, stearyl palmitate, stearyl stearate, stearyl isostearate, stearyl oleate, stearyl behenate, stearyl erucate, isostearyl myristate, isostearyl palmitate, isostearyl stearate, isostearyl isostearate, isostearyl oleate, isostearyl behenate, isostearyl oleate, oleyl myristate, oleyl palmitate, oleyl stearate, oleyl isostearate, oleyl oleate, oleyl behenate, oleyl erucate, behenyl myristate, behenyl palmitate, behenyl stearate, behenyl isostearate, behenyl oleate, behenyl behenate, behenyl erucate, erucyl myristate, erucyl palmitate, erucyl stearate, erucyl isostearate, erucyl oleate, erucyl behenate and erucyl erucate. Also suitable are esters of linear C6-C22-fatty acids with branched alcohols, in particular 2-ethylhexanol, esters of C18-C38-alkylhydroxy carboxylic acids with linear or branched C6-C22-fatty alcohols, in particular Dioctyl Malate, esters of linear and/or branched fatty acids with polyhydric alcohols (such as, for example, propylene glycol, dimerdiol or trimertriol) and/or Guerbet alcohols, triglycerides based on C6-C22-fatty acids, liquid mono-/di-/triglyceride mixtures based on C6-C18-fatty acids, esters of C6-C22-fatty alcohols and/or Guerbet alcohols with aromatic carboxylic acids, in particular benzoic acid, esters of C2-C12-dicarboxylic acids with linear or branched alcohols having 1 to 22 carbon atoms (Cetiol® B) or polyols having 2 to 10 carbon atoms and 2 to 6 hydroxyl groups, vegetable oils, branched primary alcohols, substituted cyclohexanes, linear and branched C6-C22-fatty alcohol carbonates, such as, for example, Dicaprylyl Carbonate (Cetiol® CC), Guerbet carbonates, based on fatty alcohols having 6 to 18, preferably 8 to 10, carbon atoms, esters of benzoic acid with linear and/or branched C6-C22-alcohols (e.g. Cetiol® AB), linear or branched, symmetrical or asymmetrical dialkyl ethers having 6 to 22 carbon atoms per alkyl group, such as, for example, dicaprylyl ether (Cetiol® OE), ring-opening products of epoxidized fatty acid esters with polyols, silicone oils (cyclomethicones, silicone methicone grades, etc.), aliphatic or naphthenic hydrocarbons.
The preferred oil components or co-solvents show an ester or an amide structure. Particularly preferred are adipates (Cetiol® B, Agnique® DiME 6), methyl esters of vegetable oils (Agnique ME 18RD-F, Agnique® ME 12C—F), alkyl esters (Agnique® AE 3-2EH=2-Ethylhexyl Lactate) and alkyl amides (Agnique® AMD 10)—all products available in the market from Cognis GmbH, Düsseldorf.
Suitable emulsifiers (component d) include non-ionic and anionic surfactants and their mixtures. Non-ionic surfactants include for example:
The addition products of ethylene oxide and/or propylene oxide onto fatty alcohols, fatty acids, alkylphenols, glycerol mono- and diesters and sorbitan mono- and diesters of fatty acids or onto castor oil are known commercially available products. They are homologue mixtures of which the average degree of alkoxylation corresponds to the ratio between the quantities of ethylene oxide and/or propylene oxide and substrate with which the addition reaction is carried out. C12/18 fatty acid monoesters and diesters of addition products of ethylene oxide onto glycerol are known as lipid layer enhancers for cosmetic formulations. The preferred emulsifiers are described in more detail as follows:
Typical examples of suitable partial glycerides are hydroxystearic acid monoglyceride, hydroxystearic acid diglyceride, isostearic acid monoglyceride, isostearic acid diglyceride, oleic acid monoglyceride, oleic acid diglyceride, ricinoleic acid monoglyceride, ricinoleic acid diglyceride, linoleic acid monoglyceride, linoleic acid diglyceride, linolenic acid monoglyceride, linolenic acid diglyceride, erucic acid monoglyceride, erucic acid diglyceride, tartaric acid monoglyceride, tartaric acid diglyceride, citric acid monoglyceride, citric acid diglyceride, malic acid monoglyceride, malic acid diglyceride and technical mixtures thereof which may still contain small quantities of triglyceride from the production process. Addition products of 1 to 30, and preferably 5 to 10, mol ethylene oxide onto the partial glycerides mentioned are also suitable.
Suitable sorbitan esters are sorbitan monoisostearate, sorbitan sesquiisostearate, sorbitan diisostearate, sorbitan triisostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan dioleate, sorbitan trioleate, sorbitan monoerucate, sorbitan sesquierucate, sorbitan dierucate, sorbitan trierucate, sorbitan monoricinoleate, sorbitan sesquiricinoleate, sorbitan diricinoleate, sorbitan triricinoleate, sorbitan monohydroxystearate, sorbitan sesquihydroxystearate, sorbitan dihydroxystearate, sorbitan trihydroxystearate, sorbitan monotartrate, sorbitan sesquitartrate, sorbitan ditartrate, sorbitan tritartrate, sorbitan monocitrate, sorbitan sesquicitrate, sorbitan dicitrate, sorbitan tricitrate, sorbitan monomaleate, sorbitan sesquimaleate, sorbitan dimaleate, sorbitan trimaleate and technical mixtures thereof. Addition products of 1 to 30, and preferably 5 to 10, mol ethylene oxide onto the sorbitan esters mentioned are also suitable.
The alkyl or alkenyl oligoglycosides representing also preferred emulsifiers may be derived from aldoses or ketoses containing 5 or 6 carbon atoms, preferably glucose. Accordingly, the preferred alkyl and/or alkenyl oligoglycosides are alkyl or alkenyl oligoglucosides. These materials are also known generically as “alkyl polyglycosides” (APG). The alk(en)yl oligoglycosides according to the invention correspond to formula (I):
R1O[G]p (I)
wherein R1 is an alkyl or alkenyl radical having from 6 to 22 carbon atoms, G is a sugar unit having 5 or 6 carbon atoms and p is a number from 1 to 10. The index p in general formula (I) indicates the degree of oligomerisation (DP degree), i.e. the distribution of mono- and oligoglycosides, and is a number of 1 to 10. Whereas p in a given compound must always be an integer and, above all, may assume a value of 1 to 6, the value p for a certain alkyl oligoglycoside is an analytically determined calculated quantity which is mostly a broken number. Alk(en)yl oligoglycosides having an average degree of oligomerisation p of 1.1 to 3.0 are preferably used. Alk(en)yl oligoglycosides having a degree of oligomerisation below 1.7 and, more particularly, between 1.2 and 1.4 are preferred from the applicational point of view. The alkyl or alkenyl radical R1 may be derived from primary alcohols containing 4 to 22 and preferably 8 to 16 carbon atoms. Typical examples are butanol, caproic alcohol, caprylic alcohol, capric alcohol, undecyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and technical mixtures thereof such as are formed, for example, in the hydrogenation of technical fatty acid methyl esters or in the hydrogenation of aldehydes from Roelen's oxo synthesis. Alkyl oligoglucosides based on hydrogenated C8-C16 coconut oil alcohol having a DP of 1 to 3 are preferred. Also suitable are alkoxylation products of alkyl oligoglucosides, for example adducts of 1 to 10 moles ethylene oxide and/or 1 to 5 moles propylene oxide to C8-C10 or C12-C18 alkyl oligoglucoside having a DP between 1.2 and 1.4.
Suitable emulsifiers are castor oil, rape seed oil, soy bean oil ethoxylated with 3 to 80 moles ethylene oxide (Agnique® CSO 35, Agnique® SBO 10, Agnique® SBO 60). Typical copolymers are ethoxylated and propoxylated block and/or random polymers of C2-C22 linear or branched alcohols.
Typical anionic emulsifiers encompass alkylbenzene sulfonic acids and their salts, as for example calcium dodecylbenzene sulfonate dissolved in isobutanol (Agnique® ABS 65C) or 2-ethylhexanol (Agnique® ABS 60C-EH), dialkyl sulfosuccinates, as for example di-2-ethylhexyl sulfosuccinate or dioctyl sulfosuccinate, and polyacrylates having a molar weight of from 1,000 to 50,000.
Other suitable emulsifiers are zwitterionic surfactants. Zwitterionic surfactants are surface-active compounds which contain at least one quaternary ammonium group and at least one carboxylate and one sulfonate group in the molecule. Particularly suitable zwitterionic surfactants are the so-called betaines such as the N-alkyl-N,N-dimethyl ammonium glycinates, for example cocoalkyl dimethyl ammonium glycinate, N-acylaminopropyl-N,N-dimethyl ammonium glycinates, for example cocoacylaminopropyl dimethyl ammonium glycinate, and 2-alkyl-3-carboxymethyl-3-hydroxyethyl imidazolines containing 8 to 18 carbon atoms in the alkyl or acyl group and cocoacylaminoethyl hydroxyethyl carboxymethyl glycinate. The fatty acid amide derivative known under the CTFA name of Cocamidopropyl Betaine is particularly preferred. Ampholytic surfactants are also suitable emulsifiers. Ampholytic surfactants are surface-active compounds which, in addition to a C8/18 alkyl or acyl group, contain at least one free amino group and at least one —COOH— or —SO3H— group in the molecule and which are capable of forming inner salts. Examples of suitable ampholytic surfactants are N-alkyl glycines, N-alkyl propionic acids, N-alkylaminobutyric acids, N-alkyliminodipropionic acids, Nhydroxyethyl-N-alkylamidopropyl glycines, N-alkyl taurines, N-alkyl sarcosines, 2-alkylaminopropionic acids and alkylaminoacetic acids containing around 8 to 18 carbon atoms in the alkyl group. Particularly preferred ampholytic surfactants are N-cocoalkylaminopropionate, cocoacylaminoethyl aminopropionate and C12/18 acyl sarcosine.
Depending on the nature of the biocide the products may show the following compositions:
Preferably the compositions represent aqueous solutions showing an electrolyte concentration of Ca2+ and Mg2+—taken together—of about 100 to about 1,000 and in particular about 500 to about 1,000 ppm. The compositions may also represent concentrates to be diluted with water to give aqueous formulations for end-users comprising about 0.5 to about 5, preferably about 0.5 to about 1% of the active matter represented by the concentrate.
A final embodiment of the present invention is related to the use of esters of polyhydric alcohols as defined above as hard-water compatible additives, adjuvants and/or solvents for biocides and biocide compositions. Preferably said compositions represent tank mixes.
Herbicidal compositions are formulated as dusts, granular compositions, liquid emulsions, or liquid concentrates. The salts of N-phosphonomethylglycine which are used as the active ingredients in herbicides are preferably formulated as liquid concentrates because they are, in fact, water-soluble and hygroscopic which makes them difficult to crystallize and isolate from water solutions. A good liquid concentrate exhibits good compatibility of the various ingredients, good heat and long term storage stability, and miscibility of the active ingredient with the liquid solvent. In addition, it should have minimum eye irritation and low levels of inhalation irritation. Not all liquid concentrates containing the salts of N-phosphonomethylglycine as the active ingredient exhibit these properties. As previously mentioned, the herein described PMCM compounds are phytotoxic compounds which are useful and valuable in controlling various plant species. Table 1 shows the example esters synthesized in developing this invention. Examples 1 to 3 are according to the invention, examples C1 to C7 serve for comparison.
As one can see from the results, the polyglycerol ester according to the present invention showed both, a high wetting activity and an excellent miscibility wih glyphosate with isoproyl amine (IPA) as counterion.
Esters according to the present invention with excellent miscibility in IPA Glyphosate (Examples 1 to 3) were tested as herbicide formulations in the following manner: A series of formulations were prepared by combining the isopropylamine salt of N-phosphonomethylglycine with the selected surfactants and water. In the test procedure, each individual formulation was dissolved in water and various aliquots of water were used to dilute the concentration of the formulation so as to achieve the desired application rate of about 0.6% IPA Glyphosate. Touchdown® IQ was used as an industry standard formulation. After the desired dilution was obtained, a solution was then sprayed on each of four (30 ft or 9.14 m) plots. Each plot had various weed species planted in loamy sand soil through a broadcast application. The seeds used were Johnsongrass (Echinochloa crusgalli), annual morningglory (Ipomoea lacunosa), velvetleaf (Abutilon theophrasti), Bermudagrass (Cynodon dactylon), yellow nutsedge (Cyperus esculentus) and purple nutsedge (Cyperus rotundus). Two weeks after treatment, the degree of injury or control is determined by comparison with untreated check plants of the same age. The injury rating from 0 to 100% is recorded for the grass species as percent control with 0% representing no injury and 100% representing complete control. In a similar manner, the injury rating from 0 to 100% is recorded for the broadleaf species. The results of the tests are shown in Table 2:
