Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M173/00—Lubricating compositions containing more than 10% water
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M125/00—Lubricating compositions characterised by the additive being an inorganic material
  • C10M125/06—Sulfur
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/02—Water
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/04—Elements
  • C10M2201/043—Sulfur; Selenenium; Tellurium
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2040/00—Specified use or application for which the lubricating composition is intended
  • C10N2040/20—Metal working
  • C10N2040/22—Metal working with essential removal of material, e.g. cutting, grinding or drilling
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2050/00—Form in which the lubricant is applied to the material being lubricated
  • C10N2050/01—Emulsions, colloids, or micelles

Definitions

• the present application relates to lubricants containing nanoparticulate Sulfur with an average particle diameter in the range from 10 to 1500 nm.
• Lubrication is the use of a material that improves the uniformity and ease of movement of two surfaces against each other. This means that the movement is gentle on the geometric shape (abrasion, service life) and as economically as possible (friction).
• the material used for lubrication is called lubricant.
• One of the main tasks of lubricants is to optimize power transmission. Lubricants also perform tasks such as dissipating frictional heat, protecting against corrosion or sealing. In the case of the friction of surfaces against one another, a distinction is made between hydrodynamic friction, dry friction and, as a border area between these two forms, mixed friction. The area of mixed friction is of greatest technical importance.
• lubricants lie, which include, for example, plain bearings, rolling bearings, gears, chains, precision engineering, slideways, motors, hydraulics, tools, machines and metalworking processes such as metal cutting and cold forming. Accordingly, a distinction is made between lubricants depending on the application.
• machine lubricating oils cylinder oils, turbine oils, engine oils, gear oils, compressor oils, circulation oils, hydraulic oils, insulating oils, heat transfer oils, process oils, metalworking oils, cooling lubricants, cutting oils and greases.
• the most important task of lubricants is to reduce the friction of materials moving against each other and to prevent mechanical wear in the mixed friction area.
• the sliding surfaces are separated by a liquid film, but are still so close together that individual roughness tips touch.
• the direct contact points determine the friction behavior and the wear of the materials rubbing against each other.
• high pressures and very high temperatures can occur which occasionally lead to welds ( Eating ") and tearing out particles from the composite material.
• Eating welds
• the touching and thus heated areas of the surfaces of the sliding partners are chemically changed by the formation of a well-adhering and easily shearable protective layer.
• the price-performance ratio of the known EP additives is in many cases unsatisfactory or the solubility or dispersibility in the base oils is insufficient.
• Elemental sulfur in commercially available forms e.g. B. as a sulfur bloom, is used as a lubricant additive.
• its solubility is too low in the base oils commonly used in the field of partial lubrication to achieve a sufficient lubricating effect for the usual requirements in practice. All attempts to achieve a sufficient lubricating effect by increasing the amount of sulfur used led to unacceptable results in the formulation and handling of the corresponding lubricants because of the formation of dispersions.
• the object of the present invention was EP additives and containing them To make lubricants technically available that meet the specified requirements Remedy disadvantages of the prior art.
• the invention relates to sulfur-containing lubricants which are nanoparticulate Sulfur with an average particle diameter in the range from 10 to 1500 nm, but preferably in the range from 25 to 800 nm.
• the size specifications are to be understood as the diameter in the direction of the largest Linear expansion of the particles. Receives in the manufacture of the fine particles always particles with a size that follows a distribution curve. For experimental Particle size can be determined, for example, by those skilled in the art known method of dynamic light scattering can be applied.
• the nanoparticulate sulfur particles are Invention encased by at least one surface modifier.
• this coating will provide chemical stability to oxidative and photochemical Changes during the storage of the particles improved and their Stability towards agglomeration increased. Furthermore, by a suitable Sheathing the particles improves their redispersibility and this different Dispersants are adjusted.
• Surface modification agents are to be understood as substances which are those of the surface the fine particles physically adhere, but not chemically with them react.
• the individual molecules of the surface modification agents adsorbed on the surface are essentially free of intermolecular bonds.
• Surface modifiers include, in particular, dispersants to understand. Dispersants are also among those skilled in the art, for example Terms known as emulsifiers, protective colloids, wetting agents and detergents.
• the adducts of ethylene oxide and / or of propylene oxide with fatty alcohols, Fatty acids, alkylphenols, glycerol monoesters and diesters and sorbitan monoesters and diesters of fatty acids or castor oil are known, commercially available Products. These are mixtures of homologs, the middle ones Degree of alkoxylation the ratio of the amounts of ethylene oxide and / or Propylene oxide and substrate with which the addition reaction is carried out corresponds.
• C 8/18 alkyl mono- and oligoglycosides their preparation and their use are known from the prior art. They are produced in particular by reacting glucose or oligosaccharides with primary alcohols with 8 to 18 carbon atoms.
• glycoside residue both monoglycosides in which a cyclic sugar residue is glycosidically bonded to the fatty alcohol and oligomeric glycosides with a degree of oligomerization of up to preferably about 8 are suitable.
• the degree of oligomerization is a statistical mean value which is based on a homolog distribution customary for such technical products.
• anionic emulsifiers are soaps, alkylbenzenesulfonates, Alkane sulfonates, olefin sulfonates, alkyl ether sulfonates, glycerol ether sulfonates, ⁇ -methyl ester sulfonates, Sulfofatty acids, alkyl sulfates, alkyl ether sulfates such as, for example Fatty alcohol ether sulfates, glycerol ether sulfates, hydroxy mixed ether sulfates, Monoglyceride (ether) sulfates, fatty acid amide (ether) sulfates, mono- and dialkyl sulfosuccinates, Mono- and dialkyl sulfosuccinamates, sulfotriglycerides, amide soaps, Ether carboxylic acids and their salts, fatty acid isethionates, fatty
• Zwitterionic surfactants can also be used as emulsifiers. Such surface-active compounds are referred to as zwitterionic surfactants. net, which carry at least one quaternary ammonium group and at least one carboxylate and one sulfonate group in the molecule.
• Particularly suitable zwittenonic surfactants are the so-called betaines such as the N-alkyl-N, N-dimethylammonium glycinate, for example the cocoalkyldimethylammonium glycinate, N-acylamino-propyl-N, N-dimethylammonium glycinate, for example the cocoacylaminopropyldimethylammonium glycinate, and 2-alkyl-3-carboxyl -3-hydroxyethylimidazolines each having 8 to 18 carbon atoms in the alkyl or acyl group and the cocoacylaminoethylhydroxyethylcarboxymethylglycinate.
• betaines such as the N-alkyl-N, N-dimethylammonium glycinate, for example the cocoalkyldimethylammonium glycinate, N-acylamino-propyl-N, N-dimethylammonium glyc
• Suitable emulsifiers are ampholytic surfactants.
• Ampholytic surfactants are surface-active compounds which, in addition to a C 8/18 alkyl or acyl group, contain at least one free amino group and at least one -COOH or -SO 3 H group in the molecule and are capable of forming internal salts.
• ampholytic surfactants are N-alkylglycine, N-alkylpropionic acid, N-alkylaminobutyric acid, N-alkyliminodipropionic acid, N-hydroxyethyl-N-alkylamidopropylglycine, N-alkyltaurine, N-alkyl sarcosine, 2-alkylaminopropionic acid and alkylaminoacetic acid each with about 8 to 18 C. Atoms in the alkyl group.
• Particularly preferred ampholytic surfactants are N-coconut alkyl aminopropionate, coconut acyl aminoethyl aminopropionate and C 12/18 acyl sarcosine.
• quaternary emulsifiers are also suitable, those of the esterquat type, preferably methyl-quaternized difatty acid triethanolamine ester salts, being particularly preferred.
• Protective colloids suitable as surface modifiers are e.g. natural water-soluble polymers such as B. gelatin, casein, gum arabic, lysalbic acid, Starch, albumin, alginic acid and their alkali and alkaline earth metal salts, water-soluble derivatives of water-insoluble polymeric natural substances such.
• B. Cellulose ethers such as methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose or modified carboxymethyl cellulose, hydroxyethyl starch or hydroxypropyl guar, as well as synthetic water-soluble polymers, such as.
• lubricants according to the invention is more nanoparticulate Sulfur with one or more base oils and / or base oil emulsions as well optionally dispersed one or more other additives. This can be done accordingly part of the sulfur in the solubility of the sulfur in the dispersant Solution go.
• a further possibility for the production of the ready-to-use lubricant preparations is that the nanoparticulate sulfur is first predispersed in a base oil or a base oil emulsion in the form of a lubricant additive concentrate, and this is then diluted with the same base oil or other liquid components into the desired one Application formulation is transferred.
• the nanoparticulate sulfur can also first be dispersed with water and then mixed with the other formulation components.
• the order of addition of each component to make the Lubricant preparations are usually not critical.
• the base oil used is preferably the one at the beginning mentioned groups of substances or their emulsions.
• Base oil a carboxylic acid ester such.
• lubricants which are nanoparticulate Sulfur with an average particle diameter in the range from 10 to 1500, but preferably 25 to 800 nm, dispersed in a base oil.
• the amount of nanoparticulate sulfur used in the lubricant preparation depends on the intended application. Generally the amount used of sulfur is chosen so that the concentration of that contained in the nanoparticles Sulfur - d. H. without consideration, if necessary, additionally in the nanoparticles contained surface modifier - between 0.02 and 50, preferably 0.1 and 5 wt .-% based on the total weight of the lubricant preparations lies.
• the production of the nanoparticulate contained in the lubricants according to the invention Sulfur can be made using different methods.
• the production preferably takes place in such a way that first of all from the stand processes known in the art an aqueous sulfur dispersion - also as "colloidal sulfur" called - is produced.
• aqueous sulfur dispersion also as "colloidal sulfur” called - is produced.
• Such methods are, for example described in Gmelin's Handbook of Inorganic Chemistry, Volume 9 [A], 8th edition, Verlag Chemie, Weinheim 1953, p. 485 f.
• the aqueous dispersion can be used as such for use in water-containing lubricant preparations become. If desired, you can add or remove Water a certain concentration of the dispersion can be set.
• the aqueous sulfur dispersion is freed of water, which is preferred by Freeze drying can happen.
• a Bronsted acid is also preferred a mineral acid to add to the acidic required for the reaction Adjust the pH value below 7.
• nanoparticulate Sulfur is added to the aqueous sulfur dispersion before freeze drying or more surface modifiers added.
• the type and amount of added Surface modifiers depend on their solubility in the dispersion and the intended use of those obtained after freeze-drying coated sulfur particles. So by choosing the surface modifier for example the compatibility of the sulfur nanoparticles with the rest Lubricant components of the preparation can be coordinated.
• the aqueous sulfur dispersion is produced in the presence of one or more surface modification agents, the order of their addition to the other reactants as a rule is not critical.
• the manufacture of the lubricants according to the invention can also be produced nanoparticulate sulfur are made by adding vaporous sulfur in Water, optionally one or more surface modifiers contains, condensed and then, for example, the suspension obtained freed from water by freeze drying.
• Another suitable method for producing the nanoparticulate sulfur offers evaporation technology.
• sulfur is first in a suitable dissolved organic solvent. Then the solution is so in water or another non-solvent, optionally in the presence of one dissolved therein surface-active compound given that it through homogenization of the two immiscible solvents to precipitate the comes nanoparticulate particles, with the organic solvent preferably evaporates.
• O / W emulsions can also be used or O / W microemulsions can be used.
• surface-active compounds can use the surface modification agents already explained at the beginning become.
• GAS Gel Anti Solvent Recrystallization
• the procedure uses a highly compressed gas or supercritical fluid (e.g. carbon dioxide) as a non-solvent for the crystallization of solutes.
• the compressed gas phase is introduced into the primary solution of the starting material and absorbed there, whereby the liquid volume increases, the solubility decreases and fine particles Particles are excreted.
• the PCA method Precipitation with a Compressed Fluid Anti-Solvent).
• the primary solution of the Starting material introduced into a supercritical fluid, with finely divided Form droplets in which diffusion processes take place, so that a precipitation finest particles.
• the starting material is injected with gas (e.g. carbon dioxide or propane) melted.
• gas e.g. carbon dioxide or propane
• Pressure and temperature reach near or supercritical Conditions.
• the gas phase dissolves in the solid and causes a lowering of the Melting temperature, viscosity and surface tension.
• expanding cooling effects lead to the formation of very fine particles through a nozzle.
• nanoparticulate sulfur are only to be understood as examples and are not a limitation.
• the invention further relates to a method for lubricating one another moving surfaces, in which a lubricant is used, the nanoparticulate Sulfur with an average particle diameter in the range of 10 up to 1500 nm, but preferably in the range from 25 to 800 nm.
• the nanoparticulate sulfur acts as in the lubricants according to the invention Lubricant additive, especially as an extreme pressure additive. It's special advantageous friction-reducing properties are particularly important difficult cutting processes as well as processes where a high load capacity is required.
• the invention therefore also includes methods for Metalworking using the nanoparticulate described above Sulfur and its use in metalworking oils, especially those at the cutting oils used in metal cutting.
• Trimethylolpropane oleic acid ester (Edenor TMP 05, trademark of Henkel KgaA) was used as the base oil.
• Experiment No. 1 serves as a comparison experiment (blank value).
• experiment no. 2 reference value
• 13% diisononyl pentasulfide was used as an additive; this concentration corresponds to a concentration of 5% bound sulfur.
• experiments Nos. 3 to 6 according to the invention the nanoparticulate sulfur produced according to Example 1 was used as an additive in the stated concentrations.
• comparative experiments Nos. 7 and 8 commercial sulfur bloom (Riedel de Haen) was used as an additive. To produce the test samples for experiments Nos.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Lubricants (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7915535

Family Applications (1)

Country Status (2)

Cited By (1)

Families Citing this family (4)

Citations (6)

• 1999
  • 1999-07-21 DE DE19934182A patent/DE19934182A1/de not_active Withdrawn
• 2000
  • 2000-07-12 EP EP00114894A patent/EP1070756A1/fr not_active Withdrawn

Patent Citations (6)

Also Published As

Similar Documents

Legal Events