DE1920971A1 - Oil-soluble copolymers, processes for their production and their use as oil additives - Google Patents

Description

DR. ELISABETH JUNG. DR. VOLKER VOSSIUS. DIPL.-ING. GERHARD COLDEWEY

MÖNCHEN 23 SIEGESSTRASSE 26 TELEFON 3450 67. TELEGRAM ADDRESS: INVENT / MONCHEN

TELEX 5 29 686

P 6403 (Fi / J / il)

April 24, 1969

Shell International Research Maatschappij II. V., Den iiaag, bodice lands

"Insoluble copolymers, process for their preparation and their use as oil additives "

Prio ■ Ut: April 26, 1968, Wiederlande, Hr. 6805941

The I ■: · - ':;'ag' relates to new, oil-soluble copolymers, one traversed a au: L: .xrer preparation and their use as additives to oils such as mineral lubricating oils or synthetic lubricating oils _v including thickened lubricating oils such as J ette ₇ heating oils, Kero "sine and gasolines? _ especially as smear oil additives.

The suitability of a lubricating oil for common engines (explosion engines) is to a large extent from the so-called "Pour Point" bsw » Pour point, viscosity behavior and dispersion power (Dispersant properties) of the oil determined «

Depending on the selected starting material and the method of manufacture Lubricating oils may contain significant amounts of paraffin wax, which begins to separate out when the lubricating oil drops below a certain level Temperature is cooled. As the lubricating oil cools down, more and more paraffin wax separates until the paraffin wax-oil mixture hardly or no longer flows »Die "lowest temperature at which the lubricating oil is used in a standard laboratory is still flowing, is called the "Pour Point"

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(Determination according to ASK) or flow point (determination according to DIlI). In order to rule out difficulties when using the lubricating oil, the pour point should be lower than the lowest temperature that the oil can assume when it is used -.- lubricating oils with a pour point that is too high one usually sets Polymers that lower the pour point.

'4

The relationship between the viscosity and the temperature of a lubricating oil is expressed by the so-called viscosity index (VI). The more the viscosity of a lubricating oil depends on the temperature, the lower its VI. Lubricating oils having highly temperature-dependent viscosity is one uberlicherweise certain polymers as so-called ^n. VI improver ⁿ to reduce the temperature dependence of the viscosity. The effect of these VI improvers is based in principle on the fact that these compounds thicken the lubricating oil relatively more at high temperatures than at low temperatures. There are also lubricating oils whose viscosity is only slightly temperature-dependent, but too low overall. In the case of these oils, it is sufficient to add a polymer acting as a thickening agent, ie a polymer which will widen one over another relatively

Temperature range essentially uniform thickening of the Lubricating oil causes.

Explosion engines pollute more or less during operation strong. The combustion gases leaking through the piston wall contain chemically reactive organic compounds such as Acids, aldehydes and ketones that lead to the formation of varnish-like deposits on the cylinder and piston walls. Get this

Deposits

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into the lubricating oil, they can prevent the formation of polymerization, Trigger condensation and oxidation products in the lubricating oil

in the following ..,

are partially insoluble, so that / contamination _v changes in viscosity and deterioration of the lubricating effect can occur »In addition, the presence of acidic combustion products can lead to corrosive wear. In order to counteract these effects or to prevent them, one must use lubricant additives. A variety of different polar group-containing polymers have been recommended for this purpose.

The previously recommended as lubricant additives in the literature polymers have Freq ig / one of the aforementioned Güns & gen effects, ie, they are either a pour point improver ¹¹ _t VX improvers, but thickeners or "Dispersantzusatz% do not meet several of these functions simultaneously. However, numerous polymers are also known which can improve a lubricating oil in multiple ^{ways at the same time. Examples of such multiply-acting lubricating oil additives are polymers which simultaneously act as S 1} Ueßpurikter lowerers and VI improvers as well as polymers which both VI improver and dispersant properties Some of the known multi-acting lubricating oil additives can to a certain extent even be regarded as trifunctional additives, since in addition to their effect as, for example, VI improvers and dispersant additives, they can also lower the pour point of a lubricating oil to a certain extent arf of lubricating oil additives or »polymersj which not only the VI one

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- Zi- ~

Substantially increase lubricating oil and your lubricating oil has a strong dispersing power but can also drastically lower the pour point of the lubricating oil.

The invention is therefore based on the object of creating a new class of copolymers which in solution, - z. B. solved in a lubricating oil, are highly effective VI improvers, dispersant properties own and lower the pour point.

The invention thus relates to oil-soluble copolymers at least one alkyl ester of an unsaturated monocarboxylic acid and at least one monohydroxyalkyl ester of an unsaturated one Monocarboxylic acids in which the average number of carbon atoms in the radicals of the formula OEL- (CHp) - (I) " in which η> -8, the alkyl side chains at least 12.5 una is 14.3 or less.

With regard to the above-mentioned limit values of the The average number of carbon atoms in the radicals of the formula I can be determined as follows;

A comparison of the pour point lowering effect of the invention Interpolymers in lubricating oils with those of similar interpolymers in which {however, the average number of Carbon atoms in the radicals of the formula I are higher than Ί4.5, ζ. Β «, 14.6 or 15.0, or less than 12.5, e.g. B. 12.0, is, shows that copolymers according to the invention lower the pour point of the lubricating oil to a far greater extent. Preferably the number is carbon Atoms in the groups of the formula I according to the invention Mix - * more polymeric on average between 13e0 and 14.1.

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™ * j ™

The molecular weight of copolymers according to the invention can be within further limits fluctuate «. Mixed polymers are often favorable with an average molecular weight (weight average) M "of at least 100,000 and at most 2,000,000, in particular from a minimum of 250,000 to a maximum of 1,250,000.

Another important property of polymeric lubricating oil additives is is their resistance to degradation by shearing in the engine "a consequence of a polymer at low shear stability lubricating oil additives is that the viscosity of a lubricating oil contains _s that such additives during use in the motor wirdo less was found that the Molecular weight of copolymers according to the invention plays an important role in terms of their shear stability. Copolymers according to the invention have a high shear stability, in particular when their average molecular weight M is below 750,000.

The molar ratio of the monomer units derived from the alkyl esters to the monomer units derived from the hydroxyalkyl esters in the copolymers of the invention can vary within wide limits. Copolymers according to the invention frequently contain 0.25 to 5 monomer units derived from monohydroxyalkyl esters for every 10 monomer units derived from alkyl esters. Also in Hiöblick on the fluidity of concentrates erfindungsgeraäßer Eisohpolymerer ± n Niscbpolymere oil are preferred which contain in each case 10 alkyl ester units derived from less than 5 Monohydroxyalkyleatern monomer units. A comparison, the flowability of mixed polymer concentrations, the Miscbpolysieren on 10 from AlkyXsstern derived monomer

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less than 3 units derived from monohydroxyalkyl esters Monomer units contain concentrates of bulk polymers, the monomer units derived from 10 alkyl esters 3 or contain more monomer units derived from monohydroxyalkyl esters, shows that the first-mentioned concentrates have a much better flowability. The use of the invention Mixed polymer with low polarity is not only considered on the better flowability of concentrates soldier mixed poly-

^ mere preferred, but for another reason. With falling This is because polarity takes away the thickening effect of the interpolymers zUj means that in order to achieve a certain degree of viscosity achieve au with a certain amount of mixed polymer, in which Use of copolymers with lower polarity can also choose those with a smaller molecular weight. As mentioned above, a decrease in molecular weight results in the copolymers according to the invention to an increase in Shear stability. Too great a reduction in the content of the invention However, mixed polymers on polar groups lead to

W a reduction in the dispersing power and the VI-improving effect, In view of the facts presented here, preferred copolymers according to the invention are those which contain at least 1 and at most 2 monomer units derived from hydroxyalkyl esters in the molecule.

Basically one can miselipolyse the EriiiacJtaig; on awei Build ways. Once you can use this mixed polymer * directly by Misciipolyraerisiaren of a G.axoic, of honing that out one or more alkyl esters of unsaturated monocarboxylic acids and one or more monohydroxyalkyl esters of unsaturated Plono carbon * "

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- Ό -

acids. However, the copolymers are preferably in the second possible, an indirect, way by copolymerizing a monomer mixture consisting of one or more unsaturated monocarboxylic acids and one or more alkyl esters of unsaturated monocarboxylic acids and subsequent further reaction of the acidic copolymers obtained, through which the carbox ^ groups in groups of Formula -COOR ₉ in which R is a monohydroxyalkyl radical, are converted.

As monomers for the production of copolymers according to the invention Monocarboxylic acid alkyl esters used should at least partially consist of alkyl esters, the alkyl radical of which is a group of the formula I contains. Furthermore, these alkyl esters should have such a long chain length and in such a quantitative ratio in the monomer mixture be present that the average number of carbon atoms of the radicals of the formula I in the alkyl chains is at least 12.5 and at most 14.5 is. Examples of such monomers are alkyl esters of unsaturated monocarboxylic acids, which are an «unbranched hydrocarbon chain with at least 10 carbon atoms contain, e.g. »n-decyl-j n-dodecyl-, n-tetradecyl-» n-hexadecyl and n-octadecyl esters of unsaturated monocarboxylic acids, and also alkyl esters of unsaturated monocarboxylic acids with a branched hydrocarbon chain, provided that these are a radical of the formula I contain «.

In addition to the alkyl esters of the type described above, this can Monomer mixture to be polymerized further unsaturated alkyl esters Monocarboxylic acids contain, z «, B» alkyl esters with less than

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10 carbon atoms in the alkyl radical or abea ^ llkylester, although Contain 10 or more carbon atoms in the alkyl radical, but none The remainder of the formula I. Examples of such monomers are methyl, ethyl, η-butyl, i-octyl and 2-methyldecyl esters of unsaturated compounds Monocarboxylic acids.

Copolymers according to the invention are preferably prepared using alkyl methacrylate mixtures which at least partially consist of alkyl methacrylates which _{contain a radical of the formula) n} - in which η is an integer from 11 to 17 «

It is particularly expedient to proceed to the production of those according to the invention Copolymers of an alkyl methacrylate mixture, which consists at least partially of methacrylic acid alkyl esters, which of are derived from alcohols produced by a special hydroformylation process. The alcohols in question are through Reaction of olefins with carbon monoxide and hydrogen in the presence a Komplerverbindungen produced as a catalyst, the the molecule contains a transition metal with an atomic number between 25 and 85 and at least one molecule of a biphilic ligand, containing trivalent phosphorus, trivalent arsenic or antimony. In the given context, the term "biphilic ligand "denotes a connection that has an element with a Electron pair that forms a coordination bond with is capable of a metal atom, with the proviso that this element can also accept electrons from the metal, whereby the stability of the complex is increased. Particularly favorable results can be achieved when using a complex compound, the cobalt, carbon monoxide and one or more phosphorus

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contains connections »

Using olefins as starting material, the above process can be used to produce predominantly non-alcoholic alcohols in a simple manner in one step by hydroformylation at relatively low pressure. Examples of monomers according to the invention for producing mixed polymers suitable Monohydroxyalkylestern unsaturated monocarboxylic acids include '-Ceilester divalent alcohols, such as ethyl _s englykol with unsaturated monocarboxylic acids, How-acrylic ~ and methacrylic acid., Further examples of such esters are the reaction products of cyclic ethers "out-of an oxygen atom two or "three carbon" atoms in Hing included, such as ethylene oxide and (Trimethylenoxyd * with unsaturated monocarboxylic acids such as acrylic and methacrylic acid _o preferred are interpolymers of Jbeta "-Hydroxyäthylmethacryla1» o SIeLIt to the copolymers of the invention in an indirect way by copolymerizing a monomer mixture .es from one or more unsaturated monocarboxylic acids and one or more alkyl esters of unsaturated monocarboxylic acids and subsequent further reaction of the copolymers obtained in this way, methacrylic acid is preferably used as the unsaturated monocarboxylic acid Further conversion of the copolymers containing free carboxyl groups, by means of which these carboxyl groups are converted into ester groups of the formula -GOOR, in which R is a monohydro-alkyl radical, can be carried out in various ways.

One can, for example, the copolymers with free carboxyl groups react with dihydric alcohols such as ethylene glycol

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Preferably, the tear-f carboxyl group-containing copolymers are particularly Athylenoxyd reacted with cyclic ethers, in addition to an oxygen atom contain two or three carbon atoms in the ring, such as ethylene oxide or! Irimethylenoxyd, ₅ vjeiter *

The preparation of the acidic copolymers is preferably carried out in solution in the presence of a free radical initiator, e.g. B «an azo compound or a perostyd. It is known that the proportions in which the individual monomers are incorporated into a growing copolymer molecule depend on the reactivity of the monomers in question the more reactive monomers are consumed more quickly * This means that the composition of the copolymer also changes continuously. In general, it can be said that when monomers with widely differing reactivity are interpolymerized, a product of extremely inhomogeneous composition is obtained if no special precautions are taken. This is the case when polymerizing saturated monocarboxylic acids with a alkyl esters of saturated monocarboxylic acids. However, bs wtsrde found ₃ that the speeds are eingebaui with the die.se monomers in the Mischpolymäre, are matched to one another tons ,, if m & M is the copolymerization in Anwesauheit a substance & inter alia? Ölifufert which associates with the unsaturated Monocarbongäure "Because" the the same installation potential of the monomers in the

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Mixed polymers, the molar ratio of the monomers in the mixed polymer is the same as that in the starting monomer mixture. Suitable compounds, which can associate the unsaturated monocarboxylic _acids} include aliphatic compounds containing a bound to a carbon atom of oxygen atom, such as alcohols, ethers, ketones and carboxylic acids. Preference is given to aliphatic alcohols such as (! Ethanol, ethanol, isopropanol and tert-butanol, in particular methanol. Benzene, toluene or xylene, in particular toluene, for example, can be used as the solvent for carrying out the copolymerization).

As a rule, the polymerization of monocarboxylic acids with alkyl esters of unsaturated monocarboxylic acids proceeds rapidly up to a conversion of about 90 °. Further polymerization to a conversion of $ 95 to $ 100 is, however, quite time consuming. It has been found that the polymerization can be accelerated beträchlich if, according to _w which a conversion is reached of about $ 90, a further amount of initiator of about 10 to 100 wt «# based on the originally zugeseiate amount of initiator, in the There reaction mixture.

The further implementation of the acidic copolymers to convert the free carboxyl groups into ester groups of the formula -COOR, in the R denotes a monohydroxyalkyl radical »is preferably carried out with the aid of a cyclic ether, in particular Äthylenoacyd. This reaction can be carried out in the presence of a basic substance as a catalyst. Examples of suitable ones alkaline substances are alkali metals, alkali metal oxides, alkali metal hydroxides, alkaline earth metals, alkaline earth

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«12 -

metal oxides, alkaline earth metal hydroxides and organic compounds such as triethylamine _y N-methylmorpholisu pyridine, quinoline and beta- picoline. Before eating a lithium compound is used as a catalyst. Examples of suitable lithium compounds are U _n a "lithium hydroxide hydride * _t -allcojiyde, carbonate and's acetate" Very favorable results can be achieved as a catalyst with Lithiiiinhydroxyd.

A variant of further reaction described above be ~ W is the fact that one that acidic copolymers not common as reacting in the presence of a base as a catalyst with the cyclic Ither, but the catalyst instead of the acidic compound "= polymeric incorporated previously. This can be achieved by v / ground _s that _t the mixture of mono Raeren from which the acidic copolymers is produced, one or more salts basic reacting substances with unsaturated monocarboxylic acids zusetzte The acidic copolymers obtained by polymerizing this monomer mixture may then without the use of a further catalyst be implemented with a cyclic ether. Lithium salts are preferred here too »

The reaction of the acidic copolymer with the cyclic ether can be carried out at tree temperature, but it is preferably carried out at an elevated temperature, for example at 95 to 130.degree. If the end product is liquid, the reaction can be carried out without a solvent. When a solvent is required, you can use either a polar or non-polar solvent "tends groups The mixing polymers having free carboxyl especially in a non-polar Iiöaunge *

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means to form intermolecular hydrogen bonds, as a result of which the viscosity rises sharply. For this reason, the reaction with the cyclic ether is preferably carried out in Presence of a polar solvent that prevents the formation of intermolecular hydrogen bonds. A low-boiling aliphatic alcohol is excellent for this purpose. A particularly suitable medium for implementation This reaction is a mixture of a low-boiling aliphatic alcohol and an aromatic hydrocarbon.

In the preparation of copolymers according to the invention by copolymerizing unsaturated monocarboxylic acids with alkyl esters of unsaturated monocarboxylic acids and then reacting the acidic copolymers obtained with a cyclic ether, the acidic copolymers do not have to be isolated from the reaction mixture before they are reacted with the cyclic ether Etch ether directly from the reaction mixture obtained during the interpolymerization. Is used to prepare the acidic copolymers an alcohol used for the approximation of the response speed of the individual monomers, this one-step method offers the further advantage _v that existing in the reaction mixture alcohol prevents the formation of intermolecular hydrogen bonds in the acid copolymers simultaneously ·

The copolymers of the invention can be added to general lubricating oils of various viscosities, but also synthetic lubricating oils or lubricating oils containing fatty oils * Man

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The copolymers according to the invention can also be incorporated into fats. The copolymers of the invention are of particular importance for improving mineral lubricating oils or mineral lubricating oil mixtures. The mixed polymers can be added to the lubricants as such or in the form of a concentrate obtained, for example, by mixing the mixed polymer with a smaller Kenge oil. The concentration of the copolymers according to the invention in the lubricants can vary within wide limits. Often it is between 0.1 and 1O ₇ preferably between 0.5 and 5 wt. & "

The lubricants can except the inventive copolymers more conventional additives, such as antioxidants contained _nine foam inhibitors, corrosion inhibitors, additives sur improving the lubricity and other conventional lubricant additives.

The examples illustrate the invention.

Obtained by copolymerizing a mixture of alkyl methacrylates and methacrylic acid and then Ithosylieren DET this acidic Mischpoljeren 14 are mixed according to the invention * polymers (Polymers 1 to 14) hergestellt- For comparison, one of three similarly constructed copolymer © (polymers A - 0) prepared by mixing at most a mixture of alkyl ethersylates and methacrylic acid co- polymerized, umm in the process e ^ fealtene acidic co-polymers etherified

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not c To explain the production process, which is essentially the same for all copolymers, will be used below Production of the polymer 12 described in detail *

Preparation of the polymer 12

Mixing 4-2 ₁ 5-turn # a mixture of alkyl methacrylates and methacrylic acid in the desired end product to be produced in a mixing ratio polymer with 12.5 wt _o $ methanol, 42 ₁ 5 wt * # toluene and O _t 165 wt. # Benzoylperojcydo The mixture auX is heated 80 ⁰ C and polymerized under the exclusion of oxygen. The reaction mixture is then mixed with 0.04-5% by weight of lithium hydroxide and 2 kol of ethylene oxide per equivalent of acid in the acidic copolymer. Then the mixture is heated to 110 ⁰ G, and ethoxylated it for 15 hours. Then enough thin mineral oil is added to the reaction mixture that, after removing the methanol and toluene in a film evaporator, a concentrate of the desired copolymer is obtained in the oil. The molar ratios of the various polymers produced by this process are given in the table below listed »

The following abbreviations are used in this table: C “qMA = mixture of alkyl methacrylates with 7-9 carbon atoms in the alkyl radical

^{a Gemiscil of} alkyl methacrylates with 12-15 carbon atoms in the alkyl radical consisting of a by reacting olefins with 11 - in the presence of a complex compound, the cobalt »monoxide and organically bound phosphorus containing 14 carbon atoms with carbon monoxide and hydrogen, as a catalyst manufactured 909845/1703

Allcoholgemiscli are made and bed. which the average number of carbon atoms "in the present in the alkyl chains of residues of the formula I 12 _t 9 3stj

^ nG MA, η-Ο ,, ρΜΑ, nC ^ f-iA, n-ß-GMA ISND n-g-MA GU "alkyl methacrylates having straight chain saturated alkyl groups having 10, 12, 14 _t 16 or 18 carbon atoms;

HÄWA «'Hydroxyethyl methacrylate.

The table also shows the average molecular weight (weight average) β _{w of} the polymers as follows; ie the average number of carbon atoms in the groups of formula I contained therein, which is denoted by δ.

Pol · Molar composition of the copolymers No.

A. 70. 1 98 2 18th 50 30th 1 000 12.0 B. 50 2 50 1'ϊ 26th 50 1 200 15.0 σ 37 17th 1; 5 16 30th 250 14.6 1 2 52 19th 11th 8th 50 1 200 13.2 2 1 55 24 11th 16 30th 1 200 13.5 3 1 59 22nd 11th 16 30th 1 200 13.6 4 20 46 16 11th 16 30th 1 000 15.9 5 20 1 38 14th 11th 17th 30th 1 200 14.1 6th 2 2 11th 16 30th 1 000 14.1 7th 2 22nd 10 11th 16 50 900 15.8 8th 2 52 19th 11th 16 28 1 000 15.7 9 52 19th 16 27 900 15.7 10 52 19th 27 960 13.7

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the Tabel - 52 17 - O ₁₆ MA C ₁₈ Wed I HAMJ) 1920971 δ • 13.7 continuation _J5 MA C ₁₀ MA 52 11th 16 27 S.
^L i.Taus 13.7 No. ". C _7-9 MA ί 2 52 C ₁₄ MA 11th 16 18th 570 13.7 11th 2 19th 11th 16 18th 47Ο 13.7 12th 2 19th ε 11th 22nd 260 13th 80 19th 600 14th 1

The influence of these copolymers on the pour point and the viscosity properties of a lubricating oil are tested by adding the copolymers to a distillate lubricating oil in various concentrations. The pour Pc int is determined by ASTM D 97 _β The results are! Tehenden summarized table in the night.

Composition of the lubricating oil V _k 38 ° 0 _s cS V ^ IOO ⁰ O, cS Pour Point, ° 0

Base oil Jew. $ Polymer A B. 47.2 6.64 -9 η η Il σ -9 It It. 1 62.9 10.0 -15 It It It 2 -23 n It It 3 62.3 9.8 -32 η η It 4th 62.0 9.8 -32 Il η Il 5 61.9 9.7 -32 Il η It 6th 62.0 9.6 -32 η j η η 7th 62.3 9.8 -29 Π .ι η It 8th 62.1 10.0 -29 ι » dd 9 63.2 10.0 -32 tt, | H It 9 63.0 10.0 -32 π _H It η 14th 62.7 9.9 -32 It η -40 ti, 65.3 10.4 -32 «• 1.50 ι- 1.5 ι- 4.0 f 1.5 ι 1.5 «- 1.5 H, 5 ► 1.5 ι 1.5 ► 1.5 ► 1.5 η 1.5 ι- 4.0 i- 1.5

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The pourability of 2O # iger concentrates of the above polymers in a mineral lubricating oil with a T, 100 ° C of 4.5 cS is determined with the help of a
( ¹ Se er viscometer determined. This measuring device is described in the IP method 72/58. The cross section of the outflow opening is 10 mm. The outflow time at 15 ° C. in seconds is listed below for some of the polymer concentrates investigated: Concentrate of the polymer 8 outflow 164 sec

ti η π Q ir 143 ™

η η η ι »ι 328"

The shear stability of these polymers is with the aid of an Opel pump TestB of determination this purpose, the IcPolymeren a mineral oil having a V, 100 ⁰ C of 5 »5 ATS may be added at various concentrations, containing 8 wt. ^ A commercial additive combination · nation with Detergent -, anti-rust, anti-corrosion and high pressure effects. The shear conditions in the test are as follows: Shear time 24 hours.

! Temperature 50 ° C

Speed 150O r.p.H.

amount of oil 800 g

The following results are obtained:

Y _x . 100 ° 0, cS ** Four

before the after the _Ώ . . Scissors scissors o ^

Base oil + 3.1% by weight of polymer 10 16.8 12 »8 - -34

" + 4.4" »11 16.8 14.0 -37

"+ 4.5" "12 16.7 14.3 -34

+ 5.0 " ⁿ 13 15.0 13.7 -37

"+ 3.5" "14 15.8 13.3 -37

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The Disperaantwirkung erfindun (-sgemäßer Hiöclipolyraerer is tested in a Einsylinder CLR engine purpose, be used lubricating oils _¥ 75 Gew.?a from a Kineralschmieröl with a V, 100 ⁰ C of 6.3 cS, an addition of a erfindungsßenuißen copolymers and 0 _t 4 _{t of} V-methylene-bis-2,6-di-tert-butylphenol and 1.0% by weight of triphenylphosphate exist. These scaling oils are subjected to the OLR KS Sequence VA-iTest An experiment was carried out in a lubricating oil which, instead of a copolymer according to the invention, contains a commercially available dispersant additive (a copolymer of alkyl methacrylates and E-vinylpyrrolidone).

The results of these Kotortests are listed below »

Ski oil composition Kotor sludge assessment

(50 ** clean)

Base oil +1.5 wt. # Polymer 10 57.2

¹¹ + 2.1 "" 11 35.4

¹¹ +1.5 "commercial 27.5

Additive

The effect of an additional amount of initiator added at the end of the polymerization "during the preparation of the acidic copolymers can be seen from the table below »

ORIGINAL INSPECTED 909845/1703

Monomer Concentration, wt. #

Initial benzoyl peroxide concentration Weight #

Temperature, ⁰ C

Benzoyl peroxide (added separately) "

Response time hours

0.5 2

6 7

8.5

10 12 13

Polymer 10 polymer., 5

0..08

78

42.5

0 ₉ 065 77

0.05 after hour

O 0.04

naeb.

Hours.

Conversion- conversion- conversion- conversion ^ '» lung 5 # lung, iö lung ^

15 49 69

92

96 98

90

94 96 97

96

It should be noted that the physical characteristics given above for the base oils in these tests is not already in view of the fact that the _four copolymers in the base oil
Substance but in the form of a 30 # concentrate in oil zugesafet n ^ are corrected.

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Claims (1)

- ΖΛ - Claims M ₁ ! Ü1.1 ^: "iiiche mixed polymers of at least one alkyl ester of an unsaturated monocarboxylic acid and at least one monohydroxyalkyl ester of an unsaturated monocarboxylic acid in which the average number of carbon atoms in the compounds of the formula OH ₇ - (CHp) _n - (I) ₉ in the η ^ 8, the alkyl side chains at least 12.5 and at most 14.3. 2. Oil-soluble copolymers according to claim 1 _9, characterized in that the average number of carbon atoms in the radicals of the formula I is at least 13 * 0 and at most 1 ^ ₃ ". 3ο mixed polymers according to claim 1 or 2, characterized) that the average molecular weight M is at least 100,000 and at most 2,500 COO. Mixed polymers according to Claim 3, characterized by a molecular weight R of at least 250,000 and at most 1 250,000. 5 "mixed polymers according to claim 4, characterized by a mole" Weight ß of less than 750,000. So mixed polymers according to one of Claims 1 to 5, characterized in that for every 10 monomer units derived from alkyl esters they _{contain O 5} , 25 to 5 monomer units derived from monohydroxyalkyl esters. 9098A 5/1703 7 "Mixed polymers according to claim 6, characterized in that they less for every 10 monomer units derived from alkyl esters as 3 monomer units derived from monohydroxyalkyl esters contain. δ »mixed polymers according to claim 7-j dadurcι characterized ₃ that they are based on 10 monomer units derived from alkyl esters 1 to Contain 2 monomer units derived from hydroxyalkyl esters «, . 9 »Process for the production of oil-soluble copolymers according to one of claims 1 to 8, characterized in that one one or more unsaturated monocarboxylic acids copolymerized with one or more alkyl esters of unsaturated monocarboxylic acids and the resulting acidic copolymers for. Conversion of the free carbosryl groups into groups of the formula -COOR, indder R is a monohydroxyalkyliest, reacted further 10. The method according to claim 9 _T, characterized in that for the preparation of the acidic Mischpolyirerenplethacryläure with a mixture of alkyl methacrylates mischpolyraerisiert ₉ which consists at least partially of alkyl methacrylates containing a remainder of the formula I, with the proviso that η is an integer of 11 to 17 is. 11. The method according to claim 9 or 10, de characterized ₉ that the acidic copolymers xirerden produced by I · ischpolymerisierung of methacrylic acid with a mixture of alkyl methacrylates, which is at least partially from alkyl methacrylate «- 909845/1703 bad OR, _{G {Nal} th is ,, consisting by reacting olefins with carbon monoxide and hydrogen in the presence of e: ner a Übergangsinetall having an atomic number of 23 to 85, and at least one molecular · kül a biphillic ₅ trivalent phosphorus, trivalent arsenic or trivalent antimony containing ligand containing Konrplexvorbindung alcohols produced as catalysts are produced " 12. The method according to claim 11, characterized in that for the preparation of the acidic copolymers alkyl methacrylates ver ~ used v / earths ₉ which are made from alcohols which are obtained by reacting olefins with carbon monoxide and hydrogen in the presence of cobalt _s carbon monoxide and one or several complex compounds containing phosphorus compounds are produced as a catalyst " 3 »A method according to any one of claims 9 3IS 12 _{9 9} characterized in that the acidic Mischpolymer2n Sieren by Mischpolymeri- in solution under Verv / ending einss radical initiator are hergesiaLlt, wherein the reaction mixture ₉ nachdeTc. a conversion of about 90 has been achieved, a further 10 to 100% by weight of initiator, based on the amount of initiator added to the initial reaction mixture, is added. 1 ^ - _β Process according to one of Claims 9 to 13 _9, characterized in that the copolymerization for the production of the acidic copolymers is carried out in the presence of a substance which is associated with the unsaturated / feral acids ο BATH ORIGINAL 9098 A 5/1703 15 · The method according to claim 14, characterized in that the Interpolymerization in the presence of an aliphatic alcohol is carried out. 16. The method according to claim 15 »characterized in that the . Copolymerization carried out in a mixture of an aliphatic alcohol and an aromatic hydrocarbon will, 17. Method according to one of Claims 9 to 16, characterized in that that the acidic mixed polymer with a cyclic ether, two or three in the ring besides one oxygen atom Contains carbon atoms, in the presence of a basic reacting Substance is further converted as a catalyst. 18. The method according to claim 17 »characterized in that the acidic copolymers are reacted with ethylene oxide. P 19. The method of claim 17 or 18, characterized _s that the acidic copolymers in the presence of a lithium compound are reacted further as catalyst " 20. The method according to any one of claims 17 to 19, characterized in that that the acidic copolymers are reacted further in the presence of an aliphatic alcohol 21. The method according to claim 20, characterized in that these acids Copolymers in a mixture of an aliphatic alcohol and an aromatic hydrocarbon, further 909845/1703 - 192Of 71 . implemented v / earth _o Use of copolymers according to one of Claims 1 to 8 as an additive for oils, especially lubricating oils 25 »Use according to claim 22 of the copolymers according to a of claims I. to 8 as an additive for a lubricating oil or a mixture of mineral lubricating oils « 24 »Use of the copolymers according to claims 1 to 8 according to Claim 22 or 23 in an amount of 0.1 to 10 "in particular 0 ₉ 5 to 3 ORIGINAL INSPECTED 90984 5/1703