DE2539072C2 - Lubricating oil mixture - Google Patents

Description

The invention relates to a lubricating oil mixture consisting of

a) a larger proportion of a lubricating oil and

b) a smaller proportion of a mixture of oil-soluble compounds functioning as a viscosity index improver Polymers made from an ethylene copolymer and an ester-based polymer.

The use of polymers as a viscosity index (hereinafter referred to as VI-improver additive in lubricating oils is well known. Polymers which contain C ₃ - to Cu alcohol esters of acrylic or methacrylic acid and their derivatives and have a rotational speed index (number average) in the range of SÖÖÖÖ up to 500 000 are widely used for this purpose. More recently, Zlegler-Natta copolymers of ethylene and higher α-olefins, in particular propylene and terpolymers of ethylene, a higher Λ-olefin and a nonconjugated diolefin in a molecular weight range of 10,000 to 200,000; known as VI improvers.

In general, these ethylene copolymers produced by the Ziegler-Natta synthesis are less costly Hg because of the low raw material cost and are often more effective than that on a cost / potency basis the above-mentioned V. I improvers of the acrylate ester type.

Without a diluent, the ethylene copolymers have a consistency that of heavily viscous syrups in the lower molecular weight range to elastomeric solids in the higher molecular weight range range and are therefore generally marketed as oil concentrates. Since the polyolefins in have essential hydrocarbon structure, they are with paraffin-based or naptuene-based oils Compatible with concentrations normally used in multigrade oils and divide -. does not depend on the solution at low temperatures.

Also proposed as V.I. improvers were nitrogen-containing derivatives of these copolymers, which by Oxidation of these ethylene copolymers and subsequent reaction of these oxidized derivatives with amines were obtained.

Polyalkyl acrylates have different solubility in hydrocarbons, and the pour point they give in an oil depends on the carbon chain length of the alkyl radical. In the C ₈ to C ₂ range, in which the solidification temperature of the polymers is low, the usually high oxygen content of 12.5 to 16.2% by weight limits the solubility of the polymer in hydrocarbons because of its high polarity, and it will best used in synthetic ester lubricants. In C ₄ - to C ₂₀ range increases the Erstarrur.gslemperatur rapidly, and the top of the carbon number, which has the maximum solubility in \> Petroleum lubricants which products represent paraffin waxes.

Despite considerable studies on the object, there is no precise method for predicting the V.I. change or . the compatibility of polymers of different structure when mixed with a common solvent, vie Mineral lubricating oil.

There is considerable prior art on both ethylene copolymer type VI improvers and ester-based polymer IV improvers. Many of the more recent patents on ethylene copolymer VI improvers made by the copolymerization of ethylene with higher olefins, usually propylene, generally disclose that the polymer can be used in conjunction with other additives, including in some cases other VI improvers as described, for example, in US Pat. ' _{: s}

Even more relevant is US Pat. No. 3,691,078, in which an ethylene copolymer is used as a V.I. improver in lubricating oils is described, such as in crankcase oils and oils for automatic transmissions (ATF) together with 0.1 to 10% by weight of certain pour point improvers, such as the reaction product of chlorinated wax and naphthalene, polyalkyl methacrylates. Copolymers and alkylaminoalkyl methacrylates and alkyl methacrylates and polyalkyl acrylates. It appears that the practice described therein is to only use the minimum amount. *> Polyalkylacrylate-V.! .- to use improvers as pour point depressants together with the ethylene copolymer, to achieve the desired pour point. So is such a polyalkyl acrylate V.I. improver as a Concentrate with 35 to 40 wt. »Active ingredient in a paraffinic diluent available and is in the generally used as such in a concentration of up to 1.2% by weight (about 0.4 to 0.5% by weight * effective Polyalkyl methacrylate) to achieve a pour point of -29 to -40 ° C in the ready-to-use oil.

US Pat. No. 3,697,429 describes ethylene copolymer V.I. improvers of the type described herein together with up to 2% of a pour point leather with a molecular weight of 1,000 to 50,000, the is generally characterized by C ^ u straight-chain groups, including polymers and copolymers of n-alkyl methacrylates, n-Alkyl acrylates and copolymers of alkyl fumarate and vinyl acetate include

It will be understood by those skilled in the art that lubricating oil additives are mixed into mixtures with mineral base oils which contain the additive as an effective compound in the mineral oil diluent.

The invention is based on the object of providing a lubricating oil additive that has the pour point and the Ability to lower the viscosity of a lubricating oil at low temperatures even further than previously known Additives were able to.

In the case of a generic lubricating oil mixture, this task is achieved by the characterizing features of the 4s Claim I resolved.

It has now been found that when an ester-based V.I. improver, which is produced by the presence of an oxygen and, where appropriate, nitrogen functionality Is labeled (as distinct from others in which such functionality is not available), is combined with a second V.I.-improver, which is included in the consists essentially of hydrocarbons, d. H. an ethylene-higher olefin copolymer or its oxidized> n and aminated derivative, hereinafter referred to as "Polyamlnox", achieved a complementary effect will, d. H. the combination gives the lubricating oil a lower pour point and viscosity conveyed low temperatures as if each of the additives were alone in the same concentrations as Mixture component is used.

The V.I. improver additive combinations according to the invention differ from those above mentioned US-PS 36 91 078 and 3697 429 in that according to the invention higher ratios of copolymer V.1.-improver ester-based to ethylene copolymer V.I. improvers are required than in any of the foregoing Patents is taught. The weight ratio of ester-based copolymer V.I. improver to ethylene copolymer V.I. improver is between about 0.8 to 99 and optimally about 1.5 to about 4 (where in the present "Ethylcncopolymer" which includes "Polyamlnox" -Derlvate). m>

Ethylene copolymers have been widely described and used as VI improvers in the lubricating oil industry. These ethylene copolymers can be polymerized by ethylene with a Cj-C ₁ , -, z. B. Ci- to Cn-cr-olefin, preferably propylene, and optionally one or more copolymerizable additional monomers.

The ut-olefins can be linear or branched if the branch has 3 or more carbon atoms of ^ the double bond is removed. While a single ar-olefin is preferred, mixtures of (Ί- to CiR-olefins are used. Suitable examples are propylene, I-Buien, I-pentene, 1-hexene, 1-llepien, 1-octene, I-nonene, 1-decene, 4-methyl-1-pentene, 4-methyl-1-hexene, 5-methyl-1-hexene, 4,4-dimethyl-I-

pentene, 4-methyl-1-heptene, 5-methyl-1-heptene, 6-methyl-1-heptene, 4,4-dimethyl-1-hexene, 5,6,5-trimethyl-lheptene and their mixtures.

According to the invention, ethylene / propylene copolymers are preferred. It is also possible to add a third? Monomer to form a terpolymer, to use a fourth monomer to form a tetrapolymer, and it is often desirable to use a mixture of numerous mono- and / or diolefins to make the ethylene copolymer VI improver (see U.S. Pat 22 180, 35 51 336, 35 98 738, 36 91 078, 36 97 429 and 37 90 480). One or more C ₅ to C ₂₈ diolefins can be used as the third monomer. These diolefins are also preferably linear, but may be branched if the branch is 3 or more carbon atoms from the double bond. The amount of the third monomer present in the polymer can be between 0 to about 10 mole percent, e.g. B. 0.1 to 5.0 mole percent.

Among the diolefins, which are used as a third monomer for copolymerization with ethylene and propylene include the bicyclic, acyclic or aliphatic nonconjugated diolefins with about 5 to 18 carbon atoms, preferably about 6 to 12 carbon atoms. Suitable monomers are!, S-cyclooctadiene, 1,4-hexadiene, Dicyclopentadiene, S-methylene ^ -norbornene, 5-V! Nyl-2-norbornene, 1, S-cyclododecadiene, 2,4-dimethyl-2,7-octadiene, 3 (2-methyl-l-propenyl) cyclopentene, 1,5-octadecadiene, 5-ethylidene-2-norbornene, 1,4-pentadiene, 1,5-hexadiene, 1,6 heptadiene, 1,17-octadecadiene, 5- (5'-hexenyl) -2-norbornene or 2,5-norbornadiene.

The copolymers can be prepared by polymerizing a monomer mixture which contains the following _{parts by weight v} based on 100 parts by weight of the solvent used.

Table I. wide range preferred area typical bcrexh component 0.1-10.0
0.1-20.0
0.0-2.0
IXlO- ⁷ -! XlO- ² 1.0-6.0
1.0-15.0
0.0-1.0
1 XlO- ⁶ -6 XlO- ³ 3.0-4.7
2.8-4.9
0
2.35 x 10- ⁴ -6x 10- ⁵ Ethylene
higher α-olefin
Diolefin
hydrogen

The monomer mixture can be formed in the presence of a catalytic! Polymerize amount of a catalyst mixture, which as a catalyst and a transition metal compound Cocatalyst is an organometallic compound, such as tetrachloride, vanadium oxychloride or vanadium tetrachloride and diethylaluminum chloride, trisobutylaluminum and ethylenic aluminum sesquichloride, respectively.

The preferred catalyst mixture contains 0.00001 to 0.0001 moles, e.g. B. 0.00005 moles of transition metal .15 halide catalyst and 0.00007 to 0.0007 moles of the Organoaiuminlumcokatalysatore per 100 parts of the used Solvent.

The non-reactive reaction medium can be an aromatic hydrocarbon such as toluene, a saturated one aliphatic hydrocarbon such as heptane, pentane or hexane, or a chlorinated hydrocarbon such as tetrachlorethylene, be.

All steps in this reaction should preferably be carried out in the absence of oxygen, moisture, carbon dioxide or other harmful substances. Preferably all reactants are and the catalyst pure and dry and covered with an inert gas such as nitrogen or methane.

During the polymerization, the reaction mixtures are stirred for 1 to 300 minutes, preferably 3 to 60 minutes, for example 15 minutes, and at temperatures of -4O ⁰ C to 100 ⁰ C, for example -10 ⁰ C to 70 ° C, preferably about 30 ° C and pressures of 1.03 to 71.3 kgf / cm ² , preferably 1.03 to 21.2 kgf / cm ^2, for example 5.2 kgf / cm ² .

The reaction mixture is then worked up to separate the copolymer product.
In the preferred embodiments, the ethylene content of the copolymer is controlled by varying the molar ratio of ethylene to propylene.

The ethylene / α-olefin, in particular, which is suitable according to the invention and prepared by the above method Ethylene / propylene copolymers generally have the properties summarized in the table below Characteristics:

Table II

properties wide range Preferred area Ethylene, mole% 30-80 40-70 o-olefin, mole% 10-70 25-60 third monomer, mole% 0-10 0-5 Degree of crystallinity in% by weight, determined
according to the method of Ver Strate and
Wilchinsky: Journ. of Polymer Science,
At. 9, p. 127 (1971) 0-25 3-15 ~ M, X 10-3 10-200 20-140 Λ /, x 10- ¹ 5-100 10-70

continuation

10-800 10-400 10 or 6 or underneath underneath

Properties wide range preferred range

~ M _W X I0- ¹ 'MJiA _n

While the ethylene copolymers by direct synthesis in the desired average molecular weight range (Weight average) from 10,000 to 800,000 and In the desired molecular weight distribution produced in can be, the low molecular weight polymers can also by physical degradation of a higher molecular weight Polymer, such as by extruding the polymer under high shear and / or temperature will.

Polyolefin A concentrate

This is a V.I. improver concentrate composed of 93% by weight of mineral oil and 7% by weight of an ethylene copolymer of following composition:

Polyolefin-A *>

Ethylene, mole percent 75

Propylene, mole percent 25

third monomer, mole% 0

Crystallinity, wt% 8

~ M "x \ 0-> 40

Λ /. x 10 ³ 80

A typical laboratory synthesis of this ethylene copolymer is as follows: Predried ethylene and Propylene was continuously introduced as a gas through a calibrated rotometer at 20 ° C into a glass reactor, the one with an external cooling jacket, mixer and inlet lines for the monomers, the solvent, the Main catalyst, the cocatalyst and hydrogen and an overflow line fitted into a quench tank was. Under constant operating conditions, the volume in the reactor was 700 ml. The temperature The response rate was kept at the desired level by removing the reserve load Pre-cooled and, if necessary, cold water circulate through the jacket, which is done by a sensitive Temperature controller was displayed.

The addition of hydrogen was measured using a calibrated rotometer. Solvent and catalyst were bcschickungen w meted out exactly using feed pumps.

The individual solutions of the main catalyst and cocatalyst were prepared by adding 0.75 Milllmol VOCh and 15 millimol ÄtjAIjClj diluted to 360 ml with n-heptane, dried and thoroughly Percolation through columns of impurities filled with Linde 5A molecular sieves and activated silica gel had been released. Heptane purified in the same way was used as a solvent. the Reactor charges are shown in Table III below:

Table III

Reactor loading: see above

Heptane solvent 500 ml / min.

Ethylene U8 l / min.

Propylene 5.47 l / min.

VOClj solution 7.25 ml / min.

Et ₃ Al ₂ Cl ₃ solution 7.25 ml / min.

Hydrogen 112.0 ml / min.

Reaction temperature 55 ° C

Polyolefin B concentrate

This is a V.l. improver concentrate made from 92% by weight mineral lubricating oil and 8% by weight of an ethylene copolymer of the following composition:

25 39 072 Polyolefin B 54 Ethylene, mole% 46 Propylene, mole% 0 third monomer, mole% 0 Crystallinity, wt% 60 A / "X 10- ³ 120 M " x 10- ^y 2

A typical laboratory synthesis of this copolymer can be carried out in the same general manner, as it was used to prepare the polyolefin A, but with varying the ethylene and I ^ propylene feeds. Both polyolefin A and B are common V.I. improvers.

»Polyaminox« derivatives of ethylene copolymers and terpolymers

The above-described ainylethylene polymers were oxidized and then reacted with amines with ν formation of the "polyamlnox" derivatives (the aminated-oxidized derivatives of the additive of the ethylene copolymer type discussed above).
The oxidation of hydrocarbon polymers is well known.

The reaction of oxidized ethylene copolymer with nitrogen-containing compounds, such as amines, is also well known, see for example U.S. Patents 3,076,791 and 3,785,980.

The oxidation of hydrocarbon polymer before the reaction with the amine can after numerous Processes can be carried out including hydroperoxidation of ethylene / propylene copolymers (U.S. Pat 37 85 980) and mechanical degradation during heating in air (US-PS 37 69 216).

Particularly suitable in the present case are those oxidized in mineral oil and then reacted with amines Ethylene copolymers, as described in DT-PA P 25 17 658.3. In this procedure, a Used in a wide variety of mineral lubricating oils as solvents for the polymer / oil solutions to be oxidized •earth. These oils can have a viscosity in the range of about 5 to 1000 SUS at 38 ° C, preferably 80 to 200 SUS at 38 ° C. You can use stralght-run derivatives in the lubricant range, e.g. above 316 ° C boiling, be or may have been further refined. Synthetic hydrocarbon oils are also suitable In the lubricant sector, which is produced by polymerization, oligomerization or alkylation of aromatics with J? Olefins were produced. Preference is given to oils with a sulfur content of less than 0.25% by weight. K, a nitrogen content of less than 25 micrograms per ml and an aromatic content of less than 30% by weight.

The oxidation of the copolymers and terpolymers dissolved in the oil is expediently carried out in a reactor carried out with stirring with air or with air, which with an inert gas such as nitrogen or carbon dioxide, has been pre-diluted to keep the risk of explosion to a minimum. The air or diluted Air can enter the oil / polymer solution in a fine-grained state at a temperature between about 80 and 300 ° C, preferably 100 to 230 ° C, are introduced with rapid stirring of the reactor components.

In general, the polymer content in the oil / polymer solution is 0.5 to 90, for example 4 to 60% by weight. Usually about 20 to 60% by weight of the solution is polymers when the polymer is of low molecular weight, e.g. B. an average molecular weight (number average M _n ) less than 20,000. For polymers with M _n equal to or greater than 20,000, the preferred concentrations are in the range from 4 to 20% by weight of polymer, based on the total weight of the oil / polymer solution.

The oxidation of the oil / polymer solution is carried out until the solution has a combined oxygen content from about 0.01 to 10.0, e.g. B. 0.1 to 8, preferably 0.1 to 5.0 wt .-%, depending on the composition the oil, the polymer and the concentration of the polymer in the solution.

In the present case, expressions such as "oxidized" or "o-eidized oil / polymer solution" indicate that air or that contains oxygen Gas was used for oxidation and excludes the use of other oxidizing acting reagents such as ozone.

For the amine compounds suitable for condensation with the oxidized polymer / oil solutions see below Forming the "Polyaminox" products of the invention include amines with a total number of carbon atoms from about 2 to 60, e.g. B. 3 to 30, and about 1 to 12, e.g. B. I to 6 nitrogen atoms in the molecule, wherein the amines can be hydrocarbylamines or can contain other groups, such as. B. to 4 Hydroxyl groups, alkoxy groups, amide groups or imidazoline groups.

Preferred amines are aliphatic, saturated amines, including those of the general formulas:
ftf)

R-Ν-R "and RN- (CH ₂ ) - [- N- (CH ₂ ) -] NR

II ¹ I ⁵ '!

(ό where R, R 'and R "independently represent a hydrogen atom, Ci- to C ^ -straight- or branched-chain alkyl radicals, Ci- to Cu-alkoxy-substituted C ₂ - to C ₆ -alkylene radicals, C ₂ - to Cu-hydroxy or aminoalkylene radicals or Ci- to dj-alkylamino-substituted C ₂ - to Ce-alkylene radicals, 5 are 2 to 6, preferably 2 to 4 and / or 0 to 10, preferably 2 to 6.

Examples of suitable amine compounds represented by the above formulas are:
n-octylamine, n-dodecylamine, di- (2-ethylhexyl) -amine, 1,3-diminoethane, 1,5 diamino propane. 1,4-Dlaminobu-Un, 1,6-Dlaminohexane, Diethylenetrlamine, Trläthylenetetramin, Tetraäthylenpentaamin, 1,2-Propylenkliamine, Di-M, 2-propylen) irlamin, Di- (1,3-propylene) triamine, NN-Dimethyl -l ^ -dlaminoprcpan, NN-di- (2-aminoethyl) äthylcndiamine, N, N-Dl- (2-hydroxyäthy!) - 1,3-propylenediamine, 3-dodecyloxypropylamine, N-dodecyl-U-propan ι diamine , Dilthanolamine, Morpholine, Trisydroxymethylaminomethane (THAM) or Dilsopropanolamine.

Other useful amine compounds include: allcyclic diamines, such as 1,4-DMamlnomethyl) cyclohe> ... n and heterocyclic nitrogen compounds such as imidazolines and N-aminoalkylpiperazines the general formula:

CH ₂ -CH ₂

NH ₂ - (CH ₂ ) -NN -G

CH ₂ -CH ₂

where G is a hydrogen atom or an Ω-aminoalkylene radical having 1 to 3 carbon atoms and ρ is an integer from 1 to 4. Examples include 2-pentadecylimidazoline, N- (2-aminoethyl) piperazine, N- (3-aminoethyl) ninera7ine i.inri N.N'-D! (2-Am! Noäthy!) P! PCr? .Z! n.

Other alkyleneamine compounds that can be used are dialkylaminoalkylamines, such as dimethylaminoethylamine, Methylaminopropylamine and Methylpropylaminopropylamine. These can be expressed by the formula below mark:

R ²

H ₂ NR ¹ -N

wherein R 'is an alkylene radical, e.g. B. an ethylene, propylene or butylene radical, and R ^! and R ^{J is} Ci- to C ₅ -alkyl- v> rcstc.

To produce the “Polyaminox” mixtures according to the invention, commercially available Mixtures of amine compounds can be used. For example, a method for making Alkylenamines the reaction of an alkylene halide (such as ethylene chloride or propylene dichloride) with Ammonia, resulting in a complex mixture of alkylene amines, in which nitrogen pairs are replaced by alkylene groups are connected, creating compounds such as diethylenetrlamine, triethylenetetraamine, tetraethylene pentaamine and isomers form piperazines. Similar substances can be found through the polymerization of aziridine, 2-melhylaziridine and produce azetidine.

The more important alkylene polyamine or aliphatic polyamine compounds which can be used according to the invention can be broadly referred to as an alkylene amine compound having 2 to 12 nitrogen atoms, in which nitrogen atom pairs are connected by alkylene groups with 2 to 4 carbon atoms, denote.

The reaction of the amine with the polymer solution'srbindung easy to find at a temperature of about 40 to 300 ° C, preferably 100 to 200 ⁰ C instead. Accordingly, after the oxidation of the oil / polymer solution has reached the desired level, the required amount of the amine compound, usually in the range of about 0.1 to 4 weight percent based on the weight of the polymer, can be added with mixing and the reaction mixture maintained at the required temperature while removing any water that forms. The time to complete the reaction of the amine compound with the oxidized oil / polymer solution is on the order of about 15 minutes to about 50 hours depending on the temperature, degree of mixing and reactivity of the amine compound. The finished aminated product will usually contain about 0.03 to 5, e.g. B. 0.1 to 3.0 wt .-% nitrogen, based on the total weight of the aminated polymer.

Polyolefin-C concentrate

This VI improver consists of about 92% by weight of mineral oil and 8% by weight of the "polyaminox" derivative of the oxidized in-oil mixture of 1528 g of an ethylene / propylene copolymer (about 75 mol-96 ethylene) with a Λ /, of about 130,000 and 1528 g of an ethylene / propylene copolymer (about 56 mol .- * ethylene) with an M _x of about 19,500. Each copolymer was individually dispersed in the mineral oil and oxidized by passing air through it the mixture conducted at elevated temperatures. The copolymer with about 75 mol% ethylene was oxidized at 171 ° C for 11 Ά hours. The copolymer with about 56 mol * ethylene was ^{oxidized at 171 C} C for 21 hours. Each of the two showed IR absorptions at 1720 cm " ¹ in a 5 mm cell of 0.208 and 0.244, respectively. After purging with nitrogen, this mixture of oxidized ethylene / propylene copolymers with an M _w of about 90,000 with 4.6 g of diethylenetriamine at between 25 and 100 ° C. The temperature was increased to 160 ° C. and maintained for 2 ² Λ hours under an inert nitrogen atmosphere, after which it was then cooled to 120 ° C. and bottled Concentrate showed a nitrogen content of 0.046% by weight. "

Ester-based polymers

These VI-improving, oil-soluble, ester-based polymers usually have an average molecular weight of 20,000 to 1,000,000, preferably 50,000 to 500,000 and particularly preferably 50,000 to 200,000. These ester-based polymers are essentially derived, for example, to 80% by weight or more of the total polymer, from C ₈ - to C ₂₀ -, preferably Ci ₂ - to Cu-alkyl esters of a C ₃ - to C ₈ -, preferably C> - to Ci-monoäthylenlsch unsaturated mono- or di-carboxylic acid. Ester-based VI polymers of this type are well known in the art and are usually prepared using free radical initiators, e.g. B. using a peroxide, prepared in a solvent.

in The esters from which the polymer is essentially derived include alkyl acrylate, alkyl methacrylate, Dialkyl fumarate and dialkyl itaconate.

The most common of these V.I. improvers are polymers of acrylic acid esters represented by the following formula can be represented

R.

I.
CH ₂ = C-COOR '

wherein R represents a hydrogen atom or a methyl radical and R 'represents an oil solubility group, Insbc-K special aikyi group with 8 to 24 carbon atoms. The alkyl group can be essentially straight-chain and preferably contains 12 to 18 carbon atoms, although methyl and ethyl branching are tolerated can. Examples of polyacrylic and polymethacrylic acid esters that promote oil solubility are octyl, decyl, Isodecyl, dodecyl, isododecyl, myristyl, cetyl, stearyl, elcosyl and tetracosyl polyacrylates and polymethacrylates.

^ The term "acrylic acid ester", as it is used in the present case, includes both acrylates and Methacrylates. Mixtures of alkyl acrylates and alkyl methacrylates can also be used.

Lower alkyl acrylic acid esters with alkyl groups with fewer than 8 carbon atoms, those of acrylic acid or methacrylic acid can be used in combination with the above-mentioned higher acrylic acid esters will. The presence of small alkyl groups in the copolymers can help. Properties,

. ") such as the viscosity index, ₄ u. Typical leather acrylic acid esters are methyl, ethyl, propyl, butyl, amyl and hexyl acrylates and methacrylates. These lower alkyl acrylic acid esters can be used in amounts of 0 to 25 mol%, based on the Total ester content.

In addition to the acrylic acid esters mentioned above, can be used to form the backbone in small Amounts of one or more free-radically polymer-soluble monoethylenically unsaturated compounds, in particular

Their monovinyl compounds, ie those which have a CH ₂ = C group in their structure, such as vinyl esters, for example vinyl acetate, styrene and alkyl styrenes, vinyl alkyl ethers, for example vinyl butyl ether, vinyl dodecyl ether and vinyl octadecyl ether, can be used.

. .u. ~ f «.err! Nitrogen-containing monomers and the abovementioned monomers can be synthesized, it being possible for the nitrogen-containing monomers to be represented, for example, by the following formula

R-C = C-H

I, K

R ¹ R ²

4 <where R 'and R ² denote a hydrogen atom and / or alkyl radicals and R denotes a 5- or o-membered heterocyclic nitrogen-containing ring which contains one or more hydrocarbon substituents. In the above formula, the vinyl radical can be bonded to the nitrogen atom or to a carbon atom in the radical R. Examples of such vinyl derivatives are 2-vinylpyridine, 4-vinylpyrldine, 2-methyl-5-vinylpyridine, 2-ethyl-5-vinylpyridine, "-Methyl-S-vinylpyridine, N-vinylpyrrolidone or 4-vinylpyrrolidone.

Other monomers that may be included are unsaturated amides such as those below formula

Ri

CH ₂ = C

CONHR ³

where R is a hydrogen atom or a methyl radical and R ^! a hydrogen atom or an alkyl radical with up to π to 24 carbon atoms. Such amides are obtained by reacting acrylic acid or a low molecular weight acrylic acid ester with an amine, such as butylamine, hexylamine, tetrapropylamine, cetylamine or tertiary alkyl-primary amines. The tertiary alkyl primary amines have the following characteristic structure

-CC-NH ₂
C.

wherein a tertiary carbon atom, ie one which has no hydrogen atoms, to a primary in amino radical. ie -NH ₂ . is bound. Such tertiary alkyl primary amines should contain at least about 8 and generally not more than about 24 carbon atoms in the tertiary alkyl substituent. In most cases the tertiary alkyl substituent contains from about 10 to about 24 carbon atoms. Specific examples of tertiary alkyl primary amines which are suitable for the purposes of the invention are tertiary octyl primary amine, tertiary decyl primary amine and tertiary hexadecyl primary amine, tertiary eicosyl primary amine and tertiary triacontyl primary amine. It is not necessary to use a single tertiary alkyl primary amine. In fact, it is generally expedient to use a commercially available mixture of such amines in which the tert-alkyl substituent contains from about 10 to about 24 carbon atoms. A typical mixture of such commercially available tertiary alkyl primary amines, for example, consists of tertiary alkyl primary amines having from about 12 to about 14 carbon atoms, the mixture containing an average of about 12 carbon atoms per amine molecule.

Other -ATitcrc monomers that may be included are Afnitie and mixed amide esters of the above called vinyl monocarboxylic and dicarboxylic acids. These monomers and the above-described lower alkyl acrylic acid esters, monovinylidene compounds, nitrogen-containing monomers and unsaturated amides can used individually or together in total amounts of 0 to 25 mol *, based on the total ester content will.

The specific ester-based polymers described below were used in the present invention Examples used.

Polyester-A concentrate

This was a V.l. improver concentrate of 63 wt .- * oil and 37 wt .- * of an ester-based copolymer, which consists of a main amount of about 95 mol * Cio- to Cjo-alkyl methacrylate monomer with alcohols, the had an average number of carbon atoms of 14.5, and a minor proportion (about 0.5 mol- *) one Aminomethacrylate, which had been polymerized with the aid of a free radical catalyst. That Copolymer had a nitrogen content of 0.2% by weight and a number average molecular weight from 50,000 to! 00,000.

Polyester B concentrate

This was a commercially available VI improver concentrate of 62 wt .- * oil and 38 wt .- * of an ester-based copolymer, which consists of a major proportion of Ci ₀ - to Cn-alkyl (average number of C atoms 12 to 15) - methacrylate monomers and a minor proportion of a nitrogen-containing monomer, the chemical analysis of which showed that the copolymer contained about 0.2% by weight nitrogen and had a number average molecular weight of 50,000 to 100,000.

Polyester-C concentrate

This was a commercially available V.l. 'improver additive concentrate of about 66 wt .- * oil and about 34 wt .-% a terpolymer. This additive consisted of styrene, alkyl maleate and a minor proportion of a nitrogen-containing monomer, chemical analysis of which showed that the terpolymer contained about 0.15% nitrogen and a number average molecular weight) between 50,000 and 100,000.

Polyester-D concentrate

This was a commercially available concentrate of 60% by weight oil and 40% by weight polyalkyl methacrylate. The molecular weights for the polyester concentrates are all given as number averages (M ") , which were calculated with the aid of membrane osmometry using a 3-rod Dohrmann semi-automatic recording meter, with toluene used as the solvent and at about 25 ° C was measured.

The polymer mixtures according to the invention contain about 0.8 to 99, preferably 1.0 to 9.0 and optimally 1.5 up to 4 parts by weight of the ester-based copolymer per part by weight of ethylene copolymer and / or its "polyamino"> noxw derivative.

The polymer blends of the invention can be incorporated into lubricating oil blends, e.g. B. auto crankcase oils, in concentrations within a range of about 0.1 to about 2 wt .- * ethylene copolymer and / or "polyamlnox" derlvate (on an active basis), based on the weight of the total mixtures, while for the ester-based copolymers concentrations within a range of 0.2 to 6 wt .- *, are suitable.

The total concentration of the mixture in the lubricating oil mixture is about 0.2 to about 8% by weight Entire vegetables.

Other common additives may also be present in the above lubricating oils, including dyes, Pour point depressants, extreme pressure additives, such as, for example, tricresyl phosphate, zinc dialkyldithiophosphate

3 to 8 carbon atoms, antioxidants such as phenyl-or-naphthylamine, tert.-octylphenol sulfide, biphenols such as 4,4'-

Methylene bis (2,6-di-tert-butylphenol), as well as ashless dispersants or detergents such as polyisobutenyl

succinimide or pentaerythritol ester of polyisobutenyl succinic anhydride.

Examples

The following mineral lubricating oils were used to compound the lubricants, which then ui have been tested for their viscosity, as shown in the tables below.

Solvent Neutral S-70

A solvent extracted hydrofined oil having a viscosity at 98.9 ° C of 36.5 SUS; Viscosity at 38 ° C of 74 SUS; Viscosity index of 78 and a pour point of -29 ° C.

Solvent Neutral H-75

A solvent extracted hydrofined oil having a viscosity at 98.9 ° C of 36.8 SUS; Viscosity at 38 ° C of 72 SUS; Viscosity index of 108 and a pour point of -17.8 ° C.

Solvent Neutral H-100

A solvent extracted oil having a viscosity at 98.9 ° C of 40.5 SUS; Viscosity at 38 ° C of 110 SUS; Viscosity index of 106 and a pour point of -17.8 "C.

Solvent Neutral H-150

A solvent extracted oil having a viscosity at 98.9 ° C of 155 SUS; Viscosity at 38 ° C of 44.0 3ii SUS; Viscosity index of 107 and a pour point of -17.8 "C.

Solvent Neutral H-110

£ in a mixture of 8 parts by volume of Solvent Neutral H-100 with 2 parts by volume of Solvent Neutral H-150. All Viscosity measurements were made according to ASTM D-445.

A number of experiments were carried out using blends of the various polyolefins and polymers based on esters in the oils listed above were prepared by adding a respective polymer concentrate to the oil with stirring and heating to 60 to 66 ° C until everything was dissolved. After that were the Brookfield viscosity of the mixtures is determined in Centlpoise at -40 ° C. The results obtained are shown in shown in Table IV below.

Table IV Viscosities of the polymer mixtures Example no. Polymer type and concentration (% by weight) *) Polyolefin polyester oil type Viscosity 10 ¹ at -40 ⁰ C

1 0.83% B - S-70 fixed 2 0.42% B - S-70 fixed 3 0.72% A - S-70 fixed 4th 0.36% A - S-70 fixed 4-A 0.36% C - S-70 fixed 5 - 3.9% A S-70 fixed 6th - 2.0% A S-70 21 7th - 3.9% B S-70 146.0 8th - 2.0% B S-70 9.5 9 - 3.5% C S-70 83.0 10 - 1.8% C S-70 8.9 Il 0.42'lü B 2.0% A S-70 64.0 12th 0.36% A 2.0% B S-70 17.5 13th 0.36% A 1.8% C S-70 15.8 13-A 0.36 "/ 6C 1.8% C H-75 17.2

U)

continuation

Example no. Polymer type and concentration (% by weight) *)

Polyolefin polyester oil type

Viscosity 10 ³ at -40 ⁰ C

14th 0.36% A 2.0% A H-75 32.3 14-A 0.36% C 2.0% A H-75 67.6 15th 0.72% A H-75 fixed 16 0.36% A H-75 fixed 17th - 3.9% A H-75 fixed 18th - 2.0% A H-75 92.2 19th 0.36% A 2.0% A H-75 85.7 20th 0.70% A - H-100 fixed 20-A 0.70% C - H-100 fixed 21 0.35% A - H-100 fixed 22nd - 3.8% A H-100 fixed 23 - 1.9% A. H-100 109 24 - 3.4% C H-100 fixed 25th - 1.7% C H-100 80.8 26th 0.35% A 1.9% A. H-100 128.6 26-A 0.35% C 1.9% A. H-100 176.2 27 0.35% A 1.7% C H-100 98.2 27-A 0.35% C 1.7% C H-100 105.0 28 - 3.8% B H-100 fixed 29 Ο, Γ ^ Α 1.9% B. H-100 63.0 30th 0.70% A - H-110 fixed 31 - 3.8% A H-110 fixed 32 0.35% A 1.9% A. H-110 "134.0

*) Active polymer in% by weight

The comparison of the results obtained in experiment 11 with 2 and 6; 12 with 4 and 8; 13 and 13-A with 4, 4-Λ and 10; 14 and 14-A with 4, 4-A and 6; 19 with 16 and 18; as well as 26-27-A with 19-25 shows the complementary one Effect that was achieved with the combination of polymeric polyolefin and polyester additive in comparison to use either of the two additives alone.

In order to expand these data, experiments were carried out in which mixtures of polyester polymer A and polyolefin A in various concentrations in Solvent Neutral Oil S-70 and the Viscosities of the mixtures at different temperatures were determined. To the properties of a To approximate finished oil for automatic transmissions, a detergent sachet was added to each mixture added, whereby each 2 wt .-% detergent-Inhlbitorverbindungen were present. The detergent-inhibitor combination received a mixture of Polyisobutenylbemstelnsäureanhydrid-Tetraäthylenpentaminkondensatlonsprodukt; a phosphorus-sulfur terpene; a zinc alkyldithlophosphate, an ethoxylated alkylphenol, an arylnaphthylamine and a Sillcon anti-foam agent. The results achieved are given in Table V below.

Table V

Viscosities of a mixture of polyester A and polyolefin A in S-70 neutral oil

example % Polyester by weight
A in the mixture Wt%
Polyolefin A im
mixture Wt%
Total polymer
in the mixture Saybolt Sec.
at 98.9 ° C CP at
-17.8 ° C 10 ³ CP
at - 40 ° C 33 _ 0.74 0.74 53.5 805 fixed 34 2.80 - 2.80 55.0 - 74.3 35 3.40 - 3.40 59.9 - 200 36 0.41 0.56 0.97 50.4 - 16.7 37 2.30 0.06 2.36 52.2 - 118.0 38 1.60 0.29 1.89 52.4 - 14.4 39 0.49 0.64 1.13 53.5 - 28.6

% Polyester by weight
A in the mixture Wt%
Polyolefin
mixture 25 39 072 Saybolt Sec.
at 98.9 ° C CP at
- 17.8 ° C 10 ¹ CP
at - 40 ° C continuation 0.56 0.74 57.1 1080 41.0 example 1.95 0.36 Wt%
A in the overall polymer
in genius 57.6 890 20.0 40 2.80 0.08 1.30 57.6 860 28.4 41 0.03 0.90 2.31 60.1 - 56.7 42 1.50 0.56 2.88 60.3 990 43.0 43 3.40 0.09 0.93 61.5 - 76.0 44 0.67 0.88 2.06 62.0 - 65.0 45 2.33 0.44 3.49 63.0 - 28.0 46 1.55 47 2.77

The data in Tables IV and V show that the polyolefins have greater thickening power than the polyfunctional improvers VI when they are measured at the same concentration, and that Mixtures of polyolefins and polyfunctional compounds, the 2 to 65 "of the polyolefin, based on the total content of polymer in the mixture, contain lower viscosities at low temperatures show as equivalent concentrations of each individual V.I. improver.

In addition to the lower cost of polyolefins compared to polyfunctional compounds, there is another Advantage of using mixtures with a lower pour point and improved flowability of the mixture can be seen at low temperatures. The improved flowability results in a better one Lubricant distribution from a container that has stood at low temperatures for a certain time. Table VI gives the results of a number of blends which illustrate these properties will.

Table VI

Viscosities of a mixture of polyolefin B and polyester B in an SAE 10% -30 oil

example Wt% poly
olefin B im
Mixture (d) Wt% poly
ester B im
Mixture (d) Kin. Vis.
cSt. at
98.9 "C Centipoise
at
- 17.8 ° C ASTM
Pour point
⁰ C Fluidity test,
Flow time, sec. At
- 29 ° C (C) 48 0.0 0.0 6.02 1 600 <»> - 6.7 <"> 49 0.0 2.4 11.12 1970 -35 8.8 50 0.7 0.0 11.5.5 1 800 ("» 51 0.6 0.4 10.94 : 830 below - 37.5 7.0 52 0.5 0.8 10.91 1880 below - 37.5 5.8

(a) Pour point without adding pour point depressant

(b) with the addition of 0.5% of a Stockpuiv.terniedrigers, containing a copolymer of equal molar proportions of a di-Cio-Cjo-alkyl fumarate and vinyl acetate, with a molecular weight of about IS 000 (number average)

(C) The flow time of the fluidity test is equal to the number of seconds it takes an oil sample to stand at -29 ° C for 64 hours in an ASTM D-97 glass needs to flow 1.27 cm when the glass is tilted 90 degrees.

(d) The mixture also contains base oil and other detergent inhibitor additives required to lubricate automobiles are.

Lower viscosities at lower temperatures are important for lubricants, like oils for automatic ones Gearboxes, engine oils and multigrade gear oils, as these types of fluids can be used at certain temperatures Measure to a certain maximum level that is tailored to each lubricant type and quality level Is. Lubricant compositions strive for certain minimum viscosities at high Temperatures and the aforementioned maximum viscosities at low temperatures to the to achieve desired viscometric properties. The invention makes it possible to meet these demands economically to meet, especially at operating temperatures from -51 to -5 \ 5 ° C.

wi Such a useful oil for automatic transmissions is represented by the following composition (all or part of the additives can be present):

25 39 072 Amount % Additive type link 94.2 Thinner / base oil mineral oil (or rest) (100 neutral) 0.25 Viscosity index improver Polyolefin A and polyester A 0.75 0.3 Corrosion inhibitor Phosphorus sulfur terpenes 0.3 Antioxidant Phenyl-cc-naphthylamine 0.4 Friction modifier Calcium oleate 2.0 Seal swellant Dihexyl phthalate 1.5 Dispersants Polyisobutenyluuccinimide 0.3 Antiwear additive Zinc dialkyldithiophosphate 0.002 Antifoam agents Polydimethylsiloxane

The percentages are in% by volume. except for the anti-foaming agent and the V.I. improvers that are included in Weight *, are given.

Claims (13)

Patent claims: 1. Lubricating oil mixture, consisting of a) a larger proportion of a lubricating oil and b) a smaller proportion of a mixture of oil-soluble compounds functioning as a viscosity index improver Polymers made from an ethylene copolymer and an ester-based polymer, characterized in that it is an oil-soluble polymer mixture as the viscosity index improver contains the ethylene copolymer component of 30 to 80 mol% ethylene, 10 to 70 mol% Cr-Cin-cr-olefin and about 0 to 10 mol% of d-Cjj-olefin is built up and its ester component is a polymer of a G-Cis-alkyl ester of a Cj-Cs-monoethylenically unsaturated acid, an average molecular weight (Number average) of about 20,000 to 1,000,000 and is present in an amount by weight that is 0.8 to 99 times the amount by weight of ethylene copolymer. 2. Lubricating oil mixture according to claim 1, characterized in that it contains an ethylene copolymer, whose Cr-Cn-ar-olefin component is propylene. 3. Lubricating oil mixture according to claim 1 or 2, characterized in that it is a polymer based on efer Contains in an amount by weight which is about 1.0 to about 9 times, preferably 1.5 to 4 times that Weight amount of ethylene copolymer is. 4. Lubricating oil mixture according to Claims 1 to 3, characterized in that it is an ethylene copolymer with a weight average molecular weight of about 10,000 to 800,000, an M "/ M" ratio of less than about 10 and having a degree of crystallinity of up to about 25 weight percent. 5. lubricating oil mixture according to claims 1 to 4, characterized in that the ethylene copolymer in Form of its oxidized and aminated derivative is present. 6. Lubricating oil mixture according to claims 1 to 5, characterized in that it is an ethylene copolymer contains, which is oxidized or hydroperoxidized by reaction with air or by mechanical degradation below Heating in air has been oxidized. 7. lubricating oil mixture according to claims 1 to 6, dadi'ch characterized in that the in the form of his oxidized and aminated derivative present ethylene copolymer by oxidation of the copolymer and Reaction with a polyamine has been obtained. 8. lubricating oil mixture according to claims 1 to 7, characterized in that it is an ethylene copolymer contains, which has been oxidized in a lubricating oil solution at 80 to 300 ° C until the solution has a Total oxygen content of 0.01 to 10% by weight, based on the weight of the oil solution, and that then in the oxidized oil solution with an amine with 2 to 60 carbon atoms and 1 to 12 nitrogen atoms has been aminated. 9. Lubricating oil mixture according to claims 1 to 8, characterized in that the polymer mixture in in an amount of about 0.2 to about 8% by weight, based on the total oil mash. 10. lubricating oil mixture according to claims 1 to 9, characterized in that the ethylene copolymer in an amount of from about 0.1 to about 2 weight percent and the ester-based copolymer in an amount of elwa 0.2 to 6% by weight, based on the weight of the total mixture, is present. 11. Lubricating oil mixture according to claims 1 to 10, characterized in that it is optionally used an ester-based polymer having nitrogen functionality, a polyalkyl methacrylate with a Contains average molecular weight (number average) from 50,000 to 100,000. 12. Lubricating oil mixture according to claims 1 to 11, characterized in that it is an ethylene copolymer contains, which is composed of about 75 mol% ethylene and about 25 mol% propylene and an average molecular weight (Weight average) of about 80,000. 13. Lubricating oil mixture according to claims 1 to 12, characterized in that it is used as a lubricating oil component contains an oil for automatic transmissions.