DE2312623B2 - GREASES - Google Patents

Description

10. grease concentrate according to claims 1 to 9, characterized in that it contains 20 to 50, ₀ part by weight flt alkaline earth metal salt and 10 to 30 wt .- <Vb polyurea component

Modern technology is constantly striving to provide the general public and the processing industry with machine equipment that can operate within a larger temperature range and at higher loads than those previously usual. Also , many of the newer machines operate at extremely high speeds. Many of these machines require very specific properties from the lubricants that are not available with the common ones. Therefore has the modern development tu plants operating at high speed and at high temperature, the petrochemical industry to develop a second generation of lubricants which meet the requirements of the new Machinery incited. Recently, an increasing demand for lubricants which show at temperatures practicing ^r 150 ° C in high-speed bearings and gears while e> nes period of over 500 hours of good performance, for example, was born. In addition, with the further development of the high-speed hidden bearings, the lubricant should be able to withstand the life of the bearing.

Numerous greases have been developed to meet most of the new, more stringent requirements. Many of these fats are too expensive to use in technical terms. Use standards or they only meet certain requirements, but fail in other respects. Common lubricating greases are the lithium greases that can be found everywhere. These greases are simply a mixture of a hydrocarbon base oil with lithium hydroxystearate and small amounts of other additives. Even if these greases show good lubricating properties and good behavior at medium temperatures, their use at high temperatures and in high-speed machines is not entirely satisfactory. The lithium greases age at high temperatures, especially at temperatures above 175 ^° C. The aging leads to a rapid loss of lubricating effect and ultimately to a failure of the system.

Another type of lubricating grease with excellent lubricating properties at higher temperatures consists of a lubricating oil (natural or synthetic) that contains a polyurea as an additive. Lubricating greases of this type are described in American patents 32 42 210, 32 43 372, 33 46 497, 33 76 223 and 34 01 027. DT-AS 12 81615 also describes lubricating greases based on lubricating oil, which are thickened by certain tetra-ureas, and according to DT-OS 21 38 843, polyureas are used as thickeners for fats. The polyurea component gives the grease significant high temperature resistance and actually causes slight antithioxoiropic properties, that is, an increase in viscosity with increasing shear stress on the lubricant. This property of the grease is advantageous because it prevents the detachment and loss of grease on the moving parts of the machine. While this grease solved most of the problems of the earlier lubricants, the disadvantage remained that relatively large amounts of polyurea (between 8 and 20 percent by weight) are required, which is quite expensive. In addition, the polyurea component does not add any to the lubricant High pressure properties, and EP additives must therefore also be added if high contact pressures occur. There is therefore an urgent need for greases for high temperatures and high numbers of revolutions, which have good stability over long periods of time , which show high pressure and anti-wear properties and which are relatively cheap to produce.

The aim of the invention is therefore a new lubricating grease which no longer has the disadvantages of known lubricating greases possesses, that is, which exhibits good performance in long-term use at high temperatures, relatively is inexpensive, good operating behavior at high temperatures in high-performance machines shows and has good EP properties.

These goals and their associated benefits can be achieved by using a lubricating grease

1) a lubricating oil as the main component,

2) j to 30 wt .-% of an alkaline earth salt Carboxylic acid with 1 to 3 carbon atoms and

3) 0.5 to 10% by weight of a polyurea component. made up of a polyurea or a Mixture of polyureas with at least one ureide group and a molecular weight between 375 and 2500 can be realized.

It has surprisingly been found that by adding an alkaline earth metal salt of a carboxylic acid to the Lubricating grease a 50 percent reduction in the polyurea content compared to what was previously required Amount is possible without the dropping point and the other physical properties a change Experienced. In addition, the presence of the carboxylic acid salt gives the lubricant good extreme pressure properties and therefore makes the addition of other EP additives unnecessary in many cases.

The exact mechanism behind this effect of the polyurea and the carboxylic acid salt in the It is not known to improve the properties of the grease. If the theory too can not be binding, it is to be assumed that the calcium acetate in some way with the Polyurea forms a complex compound and thus has a thickening effect. Even if the Mechanism is unknown, so it is known that there is a synergistic one between the two components There is an effect that the lubricating properties of the grease are improved to a considerably greater extent than by the polyurea or the carboxylic acid alone. For example, the combination does one remarkable increase in anti-wear properties and also increases the continuous performance of the grease in warehouses.

This improvement in the surprisingly achieved by using an alkaline earth salt of a carboxylic acid Lubricating greases is made by the following experiments

clarified, whereby lubricating greases according to the invention, which contain a polyurea component and different concentrations of calcium acetate in addition to the lubricating oil, with a lubricating grease which, in contrast, does not contain a calcium acetate component, with regard to their properties, such as penetration (Pm, according to different storage conditions), Timken load, contact pressure, load -Wear index and welding point are compared.

The grease used for comparison had the following composition:

Components

Wt%

Weight, g

Oleylamine

Toluene diisocyanate

Ethylenediamine

Zerolen-9

Neutral paraffin.

Base oil, viscosity

480 SUS at 38 ° C

NaNO2

Trimethyldihydro

quinoline polymer

5.50 y
3.36 \
0.58 y

65.66

24.29

9.44

2 188 1 336 232 26th 108 9 656 200 40

39 760

The lubricating grease used according to the invention had a calcium acetate concentration of 23.529 % By weight has the following composition:

Components

Wt%

Lubricant described above 3.529

23,539

fat 11,094} Ca (O H) 2 12,435 J. HOAc 1.177 NaNO2 0.235 Trimethyldihydroquinoline Polymer 19,313 Neutral paraffin. Base oil, Viscosity 480 SUS at 38 ° C 52.217 Zerolen-9

100.00%

The tests to determine the penetration »Ρδο« were carried out according to ASTM-217, while the Timken test, which provides information about the wear properties, with determination of the (OK) load (OK means the last weight gain in the Timken test at which the test was still passed) and the contact pressure was carried out according to ASTM D 2509 and the weld points and load weld indices according to ASTM D 2596 were determined. The ones in these investigations The results obtained are summarized in the table below.

Results: Polyurethane /
Ca {4 λπγίο Polyurethane / Fat with 6.2 7.08% polyurethane investigation Ca (CHiCOO): 3.5 5.26 8.99 4.35% Ca (CH ₃ COO): 23.5 13.95 269 267 253 300 270 Ao At ambient temperature 262 299 271 272 after 1 week 267 after 4 weeks 301 after 8 weeks at 38 ° C 257 303 281 272 after 1 week 282 after 4 weeks 310 27/30 16 after 8 weeks 30/32 27/30 22260 - Timken test, kg -25480 23570 68.3 72.7 Contact pressure, kg / cm ² 79.6 79.2 465 405 Load-wear index, kg -250/255 500+ 475 Welding point, kg (four-ball apparatus -200 kg)

In detail is the effect of the calcium acetate addition on the thickening effect of the polyurea on a lubricating grease No. 2 from FIG. 1 can be seen, where the values contained in this figure were obtained with a Charlotte G-3 laboratory mill. These values also show that by using about 12% basic calcium acetate the amount of for the production of a lubricating grease No. 2 necessary polyurea can be reduced to half.

The effect of basic calcium acetate on Timken (OK) exposure and contact pressure can be of the following F i g. 2 can be taken.

The in the F i g. 2 values contained show that in contrast to the fat according to the invention Grease that does not contain calcium acetate, the load capacity is greatly improved and the applicable contact pressure is greatly increased. The lubricating greases according to the invention also have unusual weld points (four-ball apparatus) and load weld indices. This will ii the F i g. 3 illustrates in detail.

During the welding point for the comparison fat is about 250 kg / 255 kg, are used for erfindungsge

moderate grease weld points from 405 kg to over 500 kg. The conditions are similar for the load-wear indices, as can be seen from the curve "L Wl" in FIG . 3 can be seen

The polyurea used according to the invention

Component is an organic compound with a molecular weight that is insoluble in water and oil between about 375 and 2500, having at least one ureid group and preferably no more than ach

Has ureid groups, in the best case between about 2 and 6 ureid groups. The term "polyurea" is used here to include monoureas, that is, a ureide group. A ureid group should be defined here as follows:

HN-C —NHi The polyureas should not have any terminal primary amine groups, that is, compounds with a terminal (NH2) group and no free carboxyl groups. A particularly preferred polyurea has an average of between 3 and 4 ureide groups and a molecular weight between about 600 and 1200.

A particularly preferred group of polyurea compounds has a structure which can be represented by the following general formulas:

/ O O \ O O

Il Il Il Il

R-NH-VC-NH-R ₁ -NH-C-NH-R ₂ -NH-Z ^ -C -NH-R ₁ -Nh-C-NH-R (a) O / OO \ O

Ii

R-NH-C-NH-R ₂ -NH

R-NH-he-NH-R ₁ -NH-C _{-NH-R 2} -NH-f-C-NH-R

where means:

η is an integer from 0 to 3,

R identical or different monovalent hydrocarbon radicals with 1 to 30, preferably 10 to 24 Carbon atoms,

Ri identical or different divalent hydrocarbon radicals having 2 to 30, preferably 6 to 15 carbon atoms and

R _{2 are} identical or different divalent hydrocarbon radicals having 1 to 30, preferably 2 to 10, carbon atoms.

The monovalent organic radical R contains in the compounds listed above from hydrogen and carbon and can be aliphatic, aromatic or acyclic and also combined, such as. B. aralkyl, alkyl, aryl, cycloalkyl, alkylcycloalkyl, etc. and it can be saturated or olefinically unsaturated (one or more double bonded carbon atoms, conjugated or non-conjugated). The divalent hydrocarbon radical, denoted above by Ri and R ₂ , can be aliphatic, alicyclic, aromatic or combined, for example alkylaryl, aralkyl, alkylcycloalkyl, cycloalkyiaryl, etc., the two free valences being on different carbon atoms.

The polyureas which have the structure shown by Formula ¹ (a) are prepared by reacting (n + \) moles of diisocyanate with two moles of a monoamine and (n) Mo \ of a diamine. (When π in formula (a) is zero, the diamine is omitted.) Polyureas having the structure represented by formula (b) are obtained by reacting (n) moles of a diisocyanate with (n + \) moles of a diamine and two moles of a monoisocyanate (When η in formula (b) is zero, the diisocyanate is omitted.) Polyureas having the structure represented by formula (c) are prepared by reacting (n) moles of a diisocyanate with (n) moles of a diamine and one mole of a Monoisocyanate and one mole of a monoamine (if π in formula (c) is zero, diisocyanate and diamine are left out.)

In the preparation of the above polyureas, the reactants in question (diisocyanate, monoisocyanate, diamine and monoamine) are mixed with one another in a suitable reaction vessel and in appropriate proportions. The reaction takes place in the absence of a catalyst and is initiated by simply combining the components under suitable conditions. The reaction temperatures are in the range from 20 ^° C. to 100 ^° C., and the process is carried out at atmospheric pressure. The reaction itself is exothermic, and accordingly higher temperatures are reached if the reaction is initiated at room temperature. But it can also be heated or cooled from the outside. The monoamine or monoisocyanate used in the production of the polyurea forms the terminal groups. As already stated, these terminal groups have 1 to 30, preferably 5 to 28 and in the most favorable case 6 to 25 carbon atoms. Examples of the various monoamines are pentylamine, hexylamine, heptylamine. Octylamine. Decylamine, dodecylamine, tetradecylamine. Hexadecylamine, octadecylamine, eicosylamine, dodecenylamine, hexadecenylamine, octadecenylamine, octadecadieny lamin,

Abietylamine, aniline, toluidine, naphthylamine, cumylamine, bornylamine, fenchylamine, t-butylaniline, benzylamine, j3-phenethylamine, etc. Particularly preferred amines are obtained by amidation of natural fats and oils with ammonia, with amides initially formed which are reduced to amines . According to this process, stearylamine, laurylamine, palmitylamine, oleylamine, petroselinylamine, linoleylamine, linolenylamine, eleostearylamine, etc. can be produced. Unsaturated amines are particularly suitable. Examples of monoisocyanates are hexyl isocyanate, decyl isocyanate, dodecyl isocyanate, tetradecyl isocyanate, hexadecyl isocyanate, phenyl isocyanate, cyclohexyl isocyanate, xylene isocyanate, cumene isocyanate, abietyl isocyanate, cyclooctyl isocyanate, etc.
The diamines and diisocyanates that make up the inner

Hydrocarbon bridges between the ureide groups form, have 2 to 30, preferably 2 to 26 and in the most favorable case 2 to 18 carbon atoms. For example are

Ethylenediamine, propanediamine, butanediamine, hexanediamine, dodecanediamine, octanediamine, Hexadecanediamine, cyclohexanediamine, cyclooctanediamine, phenylenediamine, toluene diamine, Xylene diamine, dianiline methane, ditoluidine methane, bis (aniline), bis (toluidine), etc.

Examples of diisocyanates are hexane diisocyanate, decane diisocyanate, octadecane diisocyanate, phenylene diisocyanate, Toluene diisocyanate, bis (diphenyl isocyanate), methylene bis (phenyl isocyanate), etc.

Another group of polyureas that can be used for the purposes of the invention corresponds to the following general formula:

R ₁ -NH-C-NH- ^ rY (d)

wherein

πι means an integer from 1 to 3, Ri has the meaning given above and X and Y have the meaning given in Table I below mean specified monovalent radicals.

Table I.

X O
yy Y O
Il Il
R ₅ -C-NH- Il
R ₅ CNH --— R ₂ - O O C.
/ \ C. / \
R ₄ N- R ₄ NR ₂ - \ /
C. \ /
C.
Μ O Il
O

In Table I, R2 is as indicated above If R3 has the meaning given above for R, R4 denotes arylene radicals with 6 to 16 Carbon atoms or alkenyl radicals with 2 to 30 carbon atoms and R5 alkyl radicals with 10 to 30 Carbon atoms or aryl radicals having 6 to 16 carbon atoms.

Polyureas of the above formula (d) can be described as amides and imides of mono-, di- and triureas. These materials are prepared by reaction of suitable carboxylic acids or inner carboxylic anhydrides with a diisocyanate and an amine or diamine by the various components are combined in a suitable reaction vessel and heated sufficiently long to a temperature in the range of 20 to 200 ⁰ C, to form the polyurea which generally takes 5 minutes to 1 hour.

Suitable carboxylic acids are aliphatic carboxylic acids having about 11 to 31 carbon atoms and aromatic carboxylic acids with 7 to 17 carbon atoms. Examples are aliphatic acids such as lauric acid, Myristic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, behenic acid, lignoceric acid etc. as well as aromatic acids such as benzoic acid, 1-naphthionic acid, 2-naphthionic acid, phenylacetic acid, Hydrocinnamic acid, cinnamic acid, mandelic acid, etc. Suitable Anhydrides are derived from dibasic acids that form a cyclic anhydride, such as. B. succinic anhydride, Maleic anhydride, phthalic anhydride, etc. Also substituted anhydrides, such as alkenyl succinic anhydrides with up to 30 carbon atoms in the alkenyl radical are suitable materials.

Suitable diisocyanates, monoisocyanates, monoamines and diamines have been described above. The polyureas are generally mixtures of compounds in which n \ is between 0 and 4 or 1 and 3, which are simultaneously present in the grease. For example, when a monoamine, a diisocyanate and a diamine are simultaneously present in the reaction mixture, as in the preparation of the ureas having the structure of formula (a). so a certain amount of the monoamine can react with both sides of the diisocyanate and form a diurea. In addition to this reaction, reactions that lead to the formation of tri-, tetra-, penta-, hexa-, octahureas, etc. can take place at the same time. Particularly good results were obtained when the polyurea had an average of four ureid groups.

The amount of polyurea in the fat blend

is chosen so that a thickening of the base oil to

the desired fat consistency occurs when the combination with the alkaline earth metal salt of the carboxylic acid he follows. In general, the amount of

Polyurea 0.5 to 10 percent by weight, advantageous

from 1 to 10 percent by weight and preferably 2

up to 7 percent by weight of the finished fat mixture.

If you want to work with a concentrate

the concentration of the polyurea in the

Base oil or an oily organic liquid wedge

between about 10 and 30 percent by weight of the finisher

Concentrate. The use of conc

stepped is a convenient method of handling unc

to transport the polyureas, which are then in front of the

To be diluted appropriately after use.

The second component of grease is there:

Alkaline earth salt of a carboxylic acid with 1 to 3 carbon atoms. All alkaline earth metals can be used , e.g. B. magnesium, calcium. Strontium, Bariun

etc. But calcium is most suitable Di <

Carboxylic acid group preferably has 1 to 3 carbons

material atoms and in the most favorable case 2 carbon atoms

me connections that are used with success

are calcium formate, barium formate Magnesi

reformate, magnesium acetate calcium acetate Stronti

umacetat barium acetate calcium propionate barium pro

pionate magnesium propionate etc.

The amount of used in the grease! Alkaline earth salt depends on the desired lubricating properties of the grease, the selected polyurea component, the type of alkaline earth salt, etc. Generally, the carboxylic acid salt will be in an amount of from 3 to 30 percent by weight of the finished fat, preferably from about 4 to 15 percent by weight of the fat

The ratio of alkaline earth metal salt to polyurea also depends on the above given conditions, but is generally from 1 to 15 parts on a weight basis of the carboxylic acid salt per part of polyurea and preferably 3 to 7 parts per part of polyurea.

A concentrate with polyurea and alkaline earth salt can also be formulated. The concentration of the carboxylic acid salt is then 20 to 50 percent by weight and preferably 25 to 40 percent by weight of the concentrate. The base oil is best used as the liquid medium for the concentrate , as it can easily be diluted to the desired fat blend .

The third component, which must be necessarily present in the inventive greases is a liquid base oil. A wide variety of naphthene-based, paraffin-based, and mixed-based lubricating oils can be used as the base oils. Other hydrocarbon oils are lubricating oils made from coal products and synthetic oils such as alkylene polymers (e.g. polymers of propylene, butylene, etc. and their mixtures), alkylene oxide polymers (e.g. alkylene oxide polymers produced by polymerizing an alkylene oxide in the presence of water or alcohols such as ethyl alcohol, for example propylene oxide polymers), carboxylic acid esters (e.g. esters obtained by esterifying a carboxylic acid such as adipic acid, azelaic acid, seboric acid, sebacic acid, alkenylsuccinic acid, fumaric acid, maleic acid, etc. with alcohol such as butyl alcohol, hexyl alcohol , 2-ethylhexyl alcohol pentaerythritol, etc.), liquid esters before phosphoric acids, alkylbenzenes, polyphenols (e.g. biphenols and terphenols), alkylbiphenol ethers, silicon polymers, such as. B.

Tetraethylsilicate, tetraisopropylsilicate,
Tetra (4-methyl-2-tetraethyl) silicate,
Hexyl (4-methyl-2-pentoxy) disilane,
Poly (methyi) siioxane and poly (methylphenoi) siioxane etc.

The base oils can be used individually or in combinations provided that they are miscible or can be made miscible by mutual solvents.

The greases having the superior properties of the present invention can be formulated by first producing the polyurea in situ, followed by the formation of the alkaline earth salt of the carboxylic acid also in the base oil. According to this embodiment , the base oil is brought into the kettle together with the precursors for polyurea and carboxylic acid salt, that is to say the reaction components for the formation of this compound. If a polyurea is to be produced which corresponds to formula (a), the required amounts of diisocyanate, diamine and monoamine are added together with the base oil. When producing polyureas corresponding to formula (b), the base oil is mixed with the desired amounts of diisocyanate, diamine and monoisocyanate. If the polyurea is to correspond to formula (c), the required amounts of diisocyanate, diamine, monoisocyanate and monoamine are added to the base oil. Brought diisocyanate and mono- or diamine into the boiler. The contents of the kettle are stirred and the temperature is increased to 20 to 160 ^° C. and this temperature is maintained until the formation of de; Polyurea is done, which generally requires about 0.5 to 3 hours.

After the polyurea is formed, alkaline earth hydroxide or oxide and carboxylic acid are added to the kettle. The ratio of alkaline earth hydroxide to carboxylic acid is between 1 and 4: 1, and preferably between 1 and 2: 1, on an equivalents basis. During the process, the kettle is kept at a temperature

ίο kept door between 21 ⁰ C and 65 ° C in order to bring about the neutralization of the alkaline earth hydroxide or oxide by the carboxylic acid. During the reactor, water is released and is best removed from the system by applying a weak vacuum of 500 bis <720 mm Hg at a temperature of about 100 ° C and above it to the fat cooker.

The fat mixture can then be further treated by subjecting it to shear hardening. This takes place by milling the fat in a roller under increased pressures. This improves the dispersion of the polyurea and the carboxylic acid salts in the base oil, which leads to a fat with a considerably improved consistency.

In addition to the polyurea and the alkaline earth metal, other additives can also be used in the inventive Ben grease can be used without the high stability and good operating behavior within can be affected over a wide temperature range. An oxidizing agent, for example, is added biüsator. This additive prevents varnish and sludge build-up on the metal divider and the corrosion of the alloy bearings. Organic compounds are used as antioxidants. the Contain sulfur, phosphorus or nitrogen, such as ζ. Β organic amines. Sulfides, hydroxysulfides. Phenols etc., alone or in combination with metals such as zinc. Tin or barium can be used. Special; are suitable stabilizers for fats

Phenyl-a-naphthylamine. Bis (alkylphenyl) amine.

Ν, Ν-diphenyl-p-phenylenediamine,

2,2,4-trimethyldihydroquinoline oligomers.
Bis (4-isopropylaminophenyl) ether.
N-acyl-p-aminophenol, N-acylphenthiazine.
N-Hydrocarbylamides der

Ethylenediaminetetraacetic acid,

Alkylphenol-formaldehyde-amine polycondensates etc.

Another additive that can be added to the lubricating greases according to the invention is a corrosion inhibitor. This is supposed to prevent the oxidation, so that the formation of acidic substances is suppressed, and it is supposed to form films on the metal surfaces which alleviate the effect of the corrosive substances on the free metal parts. Organic compounds that contain active sulfur, phosphorus or nitrogen, such as ζ, are used as corrosion inhibitors. Β organic sulfides, phosphides, metal salts of thiophosphoric acids and sulfonated waxes. Special; effective corrosion inhibitors are ammonium dino nylnaphthalene sulfonate and sodium nitrite.

Other additives that are used are sin; Metal deactivation additives. They are used to counteract or prevent the catalytic influence of metals on oxidation what happens through the formation of catalytically inactive complexes with soluble or insoluble metal ions Means for metal deactivation are complex organic see nitrogen- and sulfur-containing compounds, 2. B.

10

certain complex amines and sulfides. A well-known metal inactivating agent is mercaptobenzothiazole

In addition to the additives mentioned, various other additives such as stabilizers, strength improvers, dropping point improvers, lubricants, color additives, odor improvers can be used according to the invention etc., can be applied.

The following examples serve to further illustrate the present invention.

example 1

In this example, a diurea suitable as a thickener was prepared and examined for its properties. In a 48-1 stainless steel mixer provided with a stirrer, 3 × 750 g of neutral oil, 126 and 305 g of alkylamine were brought from tall oil. The contents were stirred at 55 ° C. for 30 minutes A further 3 × 750 g of neutral oil 126 with 95 g of toluene diisocyanate were then added to the mixer. The contents were stirred for 40 minutes and passed through a roller at 525 kp / cm ^{2 for a further 20 minutes}

The milled fat was then heated to 92 ° C. and 6 g of ethylenediamine were placed in the mixer in order to neutralize unreacted toluene diisocyanate. After rolling at 525 kp / cm ² , the fat was cooled to 65 ° C. and 2500 g of neutral oil 126 and 1708 g of hydrated lime (Ca (OH) 2) were added. 3900 g of neutral oil 126 and 1845 g of acetic acid were then added to the mixture, which was then stirred at about 65 ° C. for about 80 minutes.

The mixture was then mixed with 200 g of commercially available rust inhibitor and passed through the roller ^{again at 525 kgf / cm 2 for dispersion.} According to ASTM, the lubricating grease had a resting penetration (Po) of 207 and, after treatment with 60 double strokes, a worked penetration (P «>) of 348.

Example 2

This example aims at the preparation of a composition characteristic of the invention Explain tetraurea and calcium acetate. In a 48-1 stainless steel mixer fitted with a stirrer were 7500 g of a naphthene-paraffin oil mixture with a viscosity of 15 cSt, referred to here as "base oil" is, and brought 880 g of an alkylamine from tall oil and 92 g of ethylenediamine. The contents of the mixer would Stirred for 20 minutes at 55 ° C. and then mixed with 6000 g of base oil and 548 g of toluene diisocyanate. The stirring was continued and the temperature was kept at 65 ° C. for 30 minutes.

The contents of the kettle were then passed ^{through the roller at a pressure of 525 kp / cm 2} and then heated to 92 ° C. A small fat sample was analyzed and traces of diisocyanate were found. A further 40 g of ethylenediamine were added and mixed with the milled fat for 10 minutes at a temperature of 100 ° C. The kettle was then cooled to 65 ° C. and a further 5000 g of base oil with 2480 g of hydrated lime (Ca (OH) ₂ ) were added. Lime and base oil were mixed with the milled fat for 5 minutes, after which a further 5460 g base oil and 2800 g acetic acid were slowly added to the mixer within 25 minutes. The mixture was stirred for 30 minutes at 65 ° C. in order to ensure that the neutralization between the calcium hydroxide and the acetic acid is complete. Subsequently, 320 g of commercial rust inhibitor was added and the mixture was rolled at 525 kp / cm ² After addition of another 8920 g of base oil was again at 525 kp / cm ² rolled The product had an unworked penetration (Po) of 232 and after 60 double files a worked penetration (P ₆₀ ) of 282 (ASTM-217). The dropping point was 238 ° C (ASTM-D-2265).

The composition of a fat sample was calculated as follows:

Calcium acetate Polyurea ¹ ) More commercially available Corrosion inhibitor

Base oil

') Polyurea
O

Il / \

- TO-HN-C-NH

U, 7% by weight 3.8 wt%

0.8 wt. O / o
82 wt. O / o

! O O

Il i

1-NH-C-NH-CH ₂ -CH ₂ -NH-C

-NH -

-NH-C-NH-TO

where TO is a tall oil residue.

Example 3

This example is intended to demonstrate the effectiveness of a grease according to the invention, the polyurea and a Erdalkalicarbonsäuresäuresah contains in a long-term test in comparison with a known lithium stearate fat demonstrate. The fat according to the invention was prepared according to the method of Example 2. The lithium grease had the following composition:

Lithium hydroxystearate

Lubricating oil

Commercially available

EP additive

More commercially available

Corrosion inhibitor

9 wt. O / o
83% by weight

7.5 wt. O / o
0.4 wt%

According to ASTM, the lithium grease had a worked penetration of 320 and one after 60 double cycles Drop point according to ASTM of 182 ° C.

The two greases were subjected to a Timken test to determine the maximum continuous load and the to determine the maximum contact pressure under continuous load. The test method is in ASTM D-2509 set out. The results of this test are given in Table II below.

Tables
Timken test results load
(kg) Contact pressure
(kp / cni2) Grease 22.7
20.4 2250
844 Polyurea
Carboxylic acid salt
Lithium hydroxy
stearate fat

The Timken test provides information about wear properties of the grease at higher loads and higher contact pressure and proves the better Anti-wear properties of the grease according to the invention. From the table it can be seen that the fat According to the invention, the lithium grease is superior in terms of continuous load and in terms of contact pressure is far superior

The two greases were further subjected to a high temperature thin film test. This test provides information about the ability of the grease to lubricate a bearing over a long period of time and provides information on the service life of the bearing. In the test, the two fats were each applied in a layer 0.8 mm thick on two pieces of steel and ^{exposed to a temperature of 150 °} C. in the oven. The fats were observed for a period of time and the point in time at which the fat lost its fat-like properties (hardens or turns into a varnish when cooled) was referred to as the thin film life.

The lithium grease and the grease prepared by the procedure of Example 2 were subjected to the thin film test subjected; the results are given in Table III.

Table II)
Dünnlilm life at 150 ⁰ C

Grease Approximate condition of the fat

Lifetime at room temperature (hours)

Lithium hydroxy 300 hard and cracked stearate Polyurea 1000 fat-like Carboxylic acid salt

The above table shows that the greases produced by the process of the invention in their performance are far superior to the common lithium hydroxystearate fats. The table shows one too expected increase in service life by 330 percent.

Example 4

This example is intended to show the functionality of the lubricating grease according to the invention at low temperatures and its superiority over the conventional lithium greases. The viscosity of the grease prepared according to Example 2 was carried out at -18 ⁰ C and at - y c determined according to ASTM D-1092nd The values were compared with the viscosity of the lithium grease described in Example 3. The viscosities of the two fats are given in Table IV.

Table IV
Apparent viscosity

Grease viscosity (poise)

at -VC at -18'C

20 see - '200 see -' 20 see - '200 see -' As can be seen from the table, ^ as The grease according to the invention has a lower viscosity than the lithium grease both at −1 ° C. and at −18 ° C. The proof is particularly significant that at -18 ° C nn Test at 20 see- 'the viscosity of the invention Fat is 2000 poise less than that of lithium fat.

Example 5

This example is intended to demonstrate the effectiveness of monoureas and calcium acetate in making an improved grease. In a 1 liter Waring mixer, 140 grams of neutral oil 600 and 43.5 grams of alkylamine from tall oil were placed at room temperature. While stirring the contents, 19.9 g of phenyl isocvanate was added. The contents were stirred for about 30 minutes and then left to stand overnight.

11g calcium hydroxide was placed in the mixer and mixed intimately with the urea-oil mixture. Then 12.4 g of acetic acid were added and the mixture was stirred until neutralization had ended. The mixture was dehydrated and a further 50 g of oil were added. The fat was then milled and the milled penetration measured according to ASTM. The penetration after 60 double _{cycles (P 60} ) was 317. The milled penetration (Pw) of the monourea fat without the addition of calcium acetate is 336.

This example clearly shows the improvement in the worked penetration of the lubricating grease by means of. Addition of Calcium acetate.

Example 6

Polyurea 900 330 2800 1200 Carboxylic acid salt lithium 1000 400 4800 2300

This example is intended to generally illustrate the manufacture of various lubricating greases in accordance with the invention demonstrate. A 7.5 liter grease cooker equipped with cooling jackets and stirrers was heated to mil 1.9 1 of a lubricating oil is charged. The oil was stirred and the appropriate amounts of the polyurea vor stages, e.g. B. diisocyanates, monoisocyanates. Diamines carboxylic acids and monoamines were slowly being used in the Brought boiler. The amines were before the isocyanai

added and dissolved in the oil. The temperature de; Mixture was increased to 92 ° C and this temperature door was maintained. After about 30 minutes, a further 1.91 oil was added, which contained the corresponding amounts of an alkaline earth metal hydroxide. The boiler content was rolled at 490 kp / cm ² to there; To disperse alkaline earth hydroxide in the fat. A carboxylic acid was then added and the contents of the kettle were rolled ^{at 525 kp / cm 2 for 2 hours.} During the addition of alkaline earth hydroxide and carbonic acid

fio re the temperature was kept at 92 ° C.

After the 2 hours had elapsed, the fat was cooled to room temperature and rolled ^{twice at 490 kp / cm 2.} Then tests according to ASTtv D-2265 (dropping point) and according to the Federal Test Methoc

<> s 331.1 (Navy High Speed Bearing Test) carried out As expected, all greases showed a ratio wet good drip point and a satisfactory one! Lifespan in the storage test.

17th

Table V

18th

Mixture of polyurea precursors Type

DPM-4,4'-diisocyanate ') p-phenylenediamine octadecylamine p-toluidine hexyl isocyanate dianiline methane Bis (diphenyl isocyanate) amine from tallow t p-toluidine

Ethylene diamine Hexane diisocyanate Stearic acid Tolylene diisocyanate

p-phenylenediamine

Hydrocinnamic acid

Phenylene diisocyanate naphthylamine

Maleic anhydride decane diisocyanate amine from tall oil

Diphenylmethane - ^ '- diisocyanate. Λ Pemaerythritol tetracaproate.

lot

Carboxylic acid salt precursors
Type

4th Barium hydroxide 1 acetic acid 2.5
] 2 Calcium hydroxide 2.5
1 Formic acid 1
2.9 Magnesium hydroxide 1.2 Propionic acid 0.6 4.3 3.5 Calcium hydroxide 2.2 acetic acid 0.7 4.3 Barium hydroxide 2.5 acetic acid 2.2 1.5 Calcium hydroxide 2.4 acetic acid 4.1

For this purpose 3 sheets of drawings

Quantity (weight ⁰ /

Oil type

9.5
3 PhI C ^) 5.5
5.5 280 neutral 5.0
10.4 mineral 6.2
5.0 mineral 7.2
5.0 Alkyl methyl
siükon 5.6
4.5 mineral

Claims (9)

Patent claims: 1. Lubricating grease, consisting of 1) a lubricating oil as the main component, 2) 3 to 30% by weight of an alkaline earth metal salt of a carboxylic acid having 1 to 3 carbon atoms and 3) 0.5 to 10 wt .-% of a polyurea component, built up from a polyurea or a mixture of polyureas with at least one ureide group and a molecular weight between 375 and 2500. 2. Lubricating grease according to claim 1, characterized in that it consists of a polyurea component a polyurea or a mixture of polyureas with not more than 8, in particular with 2 to 6 ureid groups 3. Lubricating grease according to claims 1 or 2, characterized in that it is a polyurea component composed of a polyurea or a Mixture of polyureas with 3 to 4 ureide groups and a molecular weight between 600 and 1200 contains. 10 "5 20th 4. Lubricating grease according to claims 1 to 3, characterized in that it is 2 to 7 wt .-% of the Contains polyurea components 5. Lubricating grease according to claims 1 to 4, characterized in that it is 4 to 15 wt .-% contains an alkaline earth salt of carboxylic acid 6. Lubricating grease according to claims J to 5, characterized in that the alkaline earth metal salt of the carboxylic acid and the polyurea component contains in a ratio of 1 to 15, in particular 3 to 7 parts by weight of carboxylic acid salt per part by weight of polyurea. 7. Lubricating grease according to claims 1 to 6, characterized in that it contains a hydrocarbon oil as the lubricating oil. 8. Lubricating grease according to Claims 1 to 7, characterized in that it contains a calcium acetate as the alkaline earth metal salt of the carboxylic acid. 9. Lubricating grease according to claims 1 to 8, characterized in that it is a polyurea or a polyurea mixture of the general formulas: (a) R-NH-I ₇ C-NH-R ₁ -NH-C-NH-R ₂ -NH-J ₁ -C -NH-R 1 -NH-C-NH-R O / OO \ O Il Il I! I! (b) R-NH-C-NH-R ₂ -NH-IC-NH-R ₁ -NH-C-NH-R ₂ -NH ^ c -NH-R (c) R-NH O O \ O Il Il C-NH-R ₁ -NH-C-NH-R ₂ -NH-Tr-C-NH-R (d) X-f R, -NH-C contains, wherein X is a monovalent O Il R ₅ -C-NH- Il R ₄ N - group ! I ο and Y is a monovalent OR ₅ -C-NH-R ₂ - so 55 6o R ₄ NR ₂ - and R ₃ - group is and where η is an integer from Obis 3, Πι an integer from 1 to 3, R identical or different hydrocarbon radicals with 1 to 30 carbon atoms, Ri identical or different divalent hydrocarbon radicals with 2 to 30 carbon atoms, R2 identical or different divalent hydrocarbon radicals with I to 30 carbon atoms, T 23 623 R ₃ identical or different hydrocarbon radicals with 1 to 30 carbon atoms, R ₄ arylene radicals with 6 to 16 carbon atoms or alkylene radicals with 2 to 30 carbon atoms, R ₅ denotes alkyl radicals with 10 to 30 carbon atoms or aryl radicals with 6 to 16 carbon atoms.