RU2467022C2 - Methacrylate copolymer depressant additives - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: claimed invention relates to polyalkylmethacrylate copolymers. Described is polyalkylmethacrylate copolymer for lowering pour point of mineral oil composition, which includes derivatised links of: (A) from 60.0 to 96.0 wt % of C₁₂-C₁₆alkylmethakrylate and (B) from 40.0 to 4.0 wt % of C₁₈-C₃₀alkylmethacrylate, component (B) including from 40 to 50 wt % of C₁₈alkylmethacrylate, from 5 to 15 wt % of C₂₀alkylmethacrylate and from 40 to 50 wt % of C₂₂alkylmethacrylate counted per total weight of component (B). Also described is lubricating composition, which includes: (I) oil of lubricating viscosity; (II) said polyacrylmethacrylate copolymer and optionally (III) other additives.

EFFECT: improvement of low-temperature properties of lubricating compositions.

9 cl, 3 tbl, 3 ex

Description

The present invention relates to polyalkyl methacrylate copolymers having excellent low temperature properties. An object of the present invention is also the use of these copolymers as depressant additives or “index” additives for lubricating oils at low temperatures.

Polyalkyl methacrylate depressant additives are known in the lubricating oil industry. Many attempts have been made to obtain polyalkyl methacrylate depressant additives that improve the low temperature viscometric properties of various lubricant compositions.

Depressant additives (DPP) improve the low-temperature performance of oils by modifying the process of wax crystallization. A wide variety of chemical types are available that include polyalkyl methacrylates, styrene copolymerized polyesters, alkyl polystyrenes, ethylene vinyl acetate, vinyl acetate fumarate, esterified olefin polymers, styrene / maleic anhydride copolymers and alkyl naphthalenes.

The object of the present invention are alkyl methacrylate polymers that exhibit the necessary low temperature properties. More specifically, an object of the invention is an oil transfer agent that exhibits outstanding low temperature properties in lubricating oils for applications such as automatic transmission fluids, manual gearbox fluids, hydraulic fluids, greases, gear lubricants, metalworking emulsions, for applications as engine oils, engine oils for engine crankcases and hydraulic fluids for shock absorbers. There is a growing need for oils for DFP, which in low concentrations ensure optimal low-temperature performance properties.

An object of the present invention is to satisfy the need for improved DDP.

The invention, in particular, is due to the need for a depressant additive that can be used in a variety of oils at lower processing costs, which exhibits less interactions with other components of the oil, such as dispersants and inhibitors, demonstrates stability under shear conditions and, in some cases, lower gelation rates depending on the base oil than previous depressant polyalkyl methacrylates. It is also important that the DPP is soluble and compatible with the base oil and maintains the appropriate Brookfield viscosity at low temperatures. The introduction of the inventive polyalkyl methacrylates has been demonstrated. The addition of the polyalkyl methacrylates of the invention provides improved viscosity at low temperatures while maintaining acceptable depressant activity.

US2655479 describes a depressant additive composition comprising a mixture of two copolymers, the first copolymer having an average side chain length of about 12.7, while the second copolymer has an average side chain length of about 11.2.

In UK No. 1559952, a mixture of oil-soluble polyalkyl methacrylates of two classes is described as depressant additives.

No. 4,146,492 describes lubricant oil compositions comprising from about 0.5 to 30.0% by weight of a specific ethylene-propylene copolymer and from about 0.005 to 10.0% by weight of a pure copolymer polyalkyl acrylate from (A) C ₁ -C ₁₅ alkyl acrylate and (B) C ₁₆ -C ₂₂ alkyl acrylate having a mass ratio of A: B in the range of about 90:10 to 50:50, a molecular weight of 1000 to 25000, and an average length of the alkyl side chain in the range of about 11 to 16 carbon atoms.

US Pat. No. 4,867,894 discloses pour point temperature modifiers for mineral oils, including 10 to 30 mol% of linear C ₁₆ -C ₃₀ alkyl methacrylate, 10 to 80 mol% of linear C ₄ -C ₁₅ alkyl methacrylate and / or a branched C ₄ -C ₄₀ alkyl methacrylate and from 0 to 30 mol% of a nitrogen-containing monomer capable of free radical polymerization having a dispersing effect.

US No. 5312884 and 5368761 describe copolymers that can be used as depressant additives for lubricating oils, comprising from 15 to 67 mol% C ₈ -C ₁₅ alkyl (meth) acrylates, from 3 to 40 mol% C ₁₆ -C ₂₄ alkyl (meth) acrylates; and from 30 to 65 molar% of C ₁ -C ₄ alkyl methacrylates. These patent documents do not mention copolymers containing specific monomers in the specific proportions required by the present invention.

No. 5,281,329 describes copolymers that can be used as depressant additives for oils containing polyalkyl (meth) acrylate of at least two varieties: one variety having a crystallization onset temperature above 15 ° C. and one variety having a crystallization onset temperature below 15 ° C.

US Pat. No. 5,534,175 describes copolymers of unsaturated fatty acid esters derivatized using from 12 to 20 wt.% C ₁ -C ₃ alkyl (meth) acrylate, from 45 to 72 wt.% C ₁₁ -C ₁₅ alkyl (meth) acrylate and from 14 to 30 wt.% C ₁₆ -C ₂₅ alkyl (meth) acrylate.

EP-A-236844 describes pour point modifiers obtained from methyl methacrylate.

No. 6,255,261 describes copolymers prepared using 5 to 60 wt.% C ₁₁ -C ₁₅ alkyl (meth) acrylates and 95 to 40 wt.% C ₁₆ -C ₃₀ alkyl (meth) acrylates, for use as depressant additives.

The object of the present invention are polyalkyl methacrylates and their use as depressant additives for lubricating oils.

The polyalkyl methacrylate copolymers of the present invention include monomer units prepared using:

(A) from about 60.0 to about 96.0 wt.% C ₁₂ -C ₁₆ alkyl methacrylate; and

(B) from about 40.0 to about 4.0 wt.% C ₁₈ -C ₃₀ alkyl methacrylate.

Polyalkyl methacrylate copolymers can have any structure, such as linear, crosslinked, structured, slightly structured or branched chains.

Polyalkyl methacrylate copolymers are added to a lubricating oil to form a lubricating oil composition.

Another embodiment of the invention relates to a lubricating oil composition comprising:

(I) lubricating oil;

(II) the polyalkyl methacrylate copolymer according to claim 1 and optional

(Iii) other additives.

Moreover, the above composition is used to improve the low temperature properties of lubricating oil.

The term "monomer units obtained using" refers to the monomer units of the polymer obtained after the interaction of the monomer. For example, a C ₁₂ -C ₁₆ alkyl methacrylate monomer polymerizes to form a polymer with a unit derived from C ₁₂ -C ₁₆ alkyl methacrylate.

The term "monomer" itself refers to unpolymerized alkyl methacrylate.

In all cases, unless otherwise indicated, percentages are usually indicated in terms of total weight.

The term "copolymer" refers to a polyalkyl methacrylate derived from monomer units derivatized from (A) and (B).

The copolymers of the present invention have a relative weight average molecular weight in the range of from about 5,000 to about 250,000. Typically, the average weight may be in the range of from about 10,000 to about 200,000, from about 15,000 to about 150,000, and most typically from about 20,000 to about 130,000. The molecular weight distribution is usually less than 2.5 and is usually in the range of from about 1.5 to about 2.5.

The molecular weight is determined by gel permeation chromatography (GPC) using a polymethyl methacrylate standard. Therefore, the average molecular weight is determined relative to the standard, and not as absolute.

Long chain aliphatic methacrylate esters can be linear or branched.

Crosslinking agents are, for example, polyethylene unsaturated crosslinking agents.

Examples are methylenebis- (meth) acrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, N-vinyl acrylamide, divinyl benzene, tetra (ethylene glycol) diacrylate, diallyloctylamide, trimethylpropane ethoxylate triacrylate, N-yldryl acrylamide. Instead or in addition to this, other crosslinking systems can be used. So, for example, covalent crosslinking by side groups can be achieved, for example, by using ethylenically unsaturated epoxy monomers or by using multifunctional crosslinking agents other than known crosslinking systems.

The amount of component (A) can vary, for example, from about 65.0 to about 95.0 wt.% Or from about 70.0 to about 95.0, from about 80.0 to about 95.0, from about 88, 0 to about 95.0 wt.%, In terms of the obtained polyalkyl methacrylate copolymer.

The amount of component (B) can vary, for example, from about 35.0 to about 5.0 wt.% Or from about 30.0 to about 5.0, from about 20.0 to about 5.0, from about 15, 0 to about 5.0, from about 12.0 to about 5.0% by weight, based on the resulting polyalkyl methacrylate copolymer.

The weight percent of components (A) and (B) of the obtained alkyl methacrylate is calculated by the total weight of component (A) or (B) divided by the total weight of the obtained polyalkyl methacrylate copolymer, multiplied by 100. The base mass of the obtained copolymer is the mass of the copolymer itself and does not include diluent .

The term "C ₁₂ -C ₁₆ alkyl methacrylate" means an aliphatic ester of methacrylic acid having a straight or branched ester alkyl group containing from 12 to 16 carbon atoms, such as lauryl methacrylate, myristyl methacrylate, cetyl methacrylate, dodecyl methacrylate, tridecyl decyl methacrylate, tridecyl decyl methacrylate, tridecyl deacrylate, mixtures.

A preferred source of C ₁₂ -C ₁₆ alkyl methacrylate esters is lauryl methacrylate, which contains a mixture of methacrylate esters derived from a mixture of C ₁₂ -C ₁₆ alkyl alcohols. Thus, in particular, the resulting polymethacrylate copolymer comprises from about 60.0 to about 96.0 wt.% Lauryl methacrylate esters and from about 65.0 to about 95.0 wt.% Lauryl methacrylate esters.

Alternatively, the weight percent for component (A) can be varied as described above for lauryl methacrylate.

In an example in which lauryl methacrylate esters are used to prepare component (A) of the polyalkyl methacrylate copolymers, lauryl ether is prepared from alcohols with a straight or branched chain distribution of C ₁₂ -C ₁₆ . Mass percent of compositions comprising lauryl methacrylate esters may be in the range below.

Distribution of lauryl methacrylates

Chain length From 12 From 14 From 16 wt.% 68-74 20-26 2-6

The determination of the mass percent of various homologues in lauryl methacrylate means the mass percentage in terms of the total mass of lauryl methacrylate. If the total lauryl methacrylate fraction is 100 g and the C 12 fraction is 68 g, the mass percentage of the C 12 component is 68 wt.% Of the total lauryl methacrylate.

In a preferred embodiment, the alkyl chains of component (A) are substantially linear.

In a preferred embodiment, aliphatic C ₁₂ -C ₁₆ esters contain only ester chains of equal length (C 12, C 14 and C 16), but odd ester chains of equal lengths (C 12, C 13, C 14, C 15 and C 16). In the case where only chains of equal length are used, component (A) contains mainly aliphatic C ₁₂ -, C ₁₄ - and C ₁₆ esters,

(A) may essentially consist of from about 60.0 to about 96 wt.% C ₁₂ -, C ₁₄ - and C ₁₆ alkyl methacrylates.

In the fraction (A), homologues of C 12 and C 14 are generally dominant. Thus, for example, at least about 80.0 wt.% Of the fraction (A) are C 12 and C 14. As a rule, C 12 and C 14 are at least from 85.0 to 88% by weight of fraction (A).

The term “essentially consists of” means that small amounts of other monomers capable of polymerizing with alkyl methacrylates may be contained, so long as they do not adversely affect the low temperature properties of fully constituted fluids.

The average chain lengths of the C ₁₂ -C ₁₆ alkyl methacrylates of component (A) range from about 12 to about 13 carbon atoms.

The term “C ₁₈ -C ₃₀ alkyl methacrylate” means a methacrylic acid alkyl ester having a straight or branched alkyl group containing from 18 to 30 carbon atoms per group, such as stearyl methacrylate, octadecyl methacrylate, heptadecyl methacrylate acrylate acrylate acrylate acrylate, nonadecylmethacrylate acrylate acrylate acrylate tetracosyl methacrylate, pentacosyl methacrylate, hexacosyl methacrylate, octacosyl methacrylate, nonacosyl methacrylate, triacontyl methacrylate, behenyl methacrylate and mixtures thereof.

A possible source for C ₁₈ -C ₃₀ alkyl methacrylate esters is behenyl methacrylate esters. The behenyl methacrylate used in these examples contains a number of long chain methacrylate esters in which ester chains are in the range of C ₁₈ to C ₂₂ . Thus, in particular, from about 40.0 to about 4.0 wt.% Of behenyl methacrylate esters comprise the obtained polyalkyl methacrylate copolymer. Thus, for example, from 35.0 to about 5.0 wt.%, From about 30 to about 5.0, or from about 20 to about 5.0 wt.% Of the obtained polyalkyl methacrylate copolymer, behenyl methacrylate esters form.

In an example in which behenyl methacrylate esters are used to prepare component (B) of the polyalkyl methacrylate copolymers, these behenyl esters can be prepared from long chain alcohols with a distribution of C ₁₈ -C ₂₂ . Mass percentages of the compositions of behenyl methacrylate esters can be in the range as given below.

Distribution of Behenyl Methacrylates

Chain length From 18 From 20 C 22 wt.% 40-50 5-15 40-50

When referring to the weight percent distribution of a particular ester in behenyl methacrylate, the weight percent is indicated based on the total weight of behenyl methacrylate.

Behenylmethacrylate can consist of essentially from about 40.0 to about 50.0, preferably from 42.0 to about 48.0 wt.%, C ₁₈ alkyl methacrylate, from about 5.0 to about 15.0, preferably from 6, 5 to about 12.0 wt.%, C ₂₀ alkyl methacrylate and from about 40.0 to about 50.0, preferably 42.0 to about 48.0 wt.%, C ₂₂ alkyl methacrylate, based on the total weight of behenyl methacrylate.

Behenylmethacrylate is almost linear and contains mainly C ₁₈ -C ₂₂ alkyl methacrylates. Behenyl methacrylate may include a small amount of C ₁₆ alkyl. Thus, for example, behenyl methacrylate typically contains less than 0.8 wt.% C ₁₆ alkyl or less than 0.5 wt.% C ₁₆ alkyl.

The total weight percent of C ₁₆ - and C ₁₈ alkyl methacrylates in the resulting copolymer usually does not exceed about 22.0 to 23.0 wt.%. So, for example, the combined weight percent of C ₁₆ alkyl and C ₁₈ alkyl fractions can be about 15.0, 16.0, 17.0, 18.0, 19.0 or 21.0 wt.% Of the obtained alkyl methacrylate from the components (A ) and (B) with a minimum of at least 7.0, 8.0 or 9.0 wt.% for the total weight percent of C ₁₆ alkyl and C ₁₈ alkyl methacrylates. So, in particular, components (A) and (B) are further defined as including the combined weight percent of C ₁₆ alkyl and C ₁₈ alkyl methacrylates, the combined mass of which is in the range from an approximate minimum of 7.0 wt.% To an approximate maximum of 23.0 wt.% in terms of the total weight of the polymethacrylate copolymer.

Moreover, the alkyl methacrylate esters in component (B), which are equal to or greater than C 20, comprise at least about 2.0 to about 40.0% by weight of the obtained polyalkyl methacrylate copolymer. So, for example, a minimum of about 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 6.0, 7.0 or 8.0 wt.% Of the obtained polyalkyl methacrylate copolymer is obtained from C ₂₀ -C ₃₀ alkyl methacrylate esters. The resulting polyalkyl methacrylate copolymer is formed from a maximum of about 10.0, 20.0, 30.0 or 40.0 wt.% C ₂₀ -C ₃₀ alkyl methacrylate esters.

Components (B) are further defined as including the combined weight percent of C ₂₀ -C ₃₀ alkyl methacrylate esters, the mass of which ranges from a minimum of about 2.0 wt.% To a maximum of about 40.0 wt.%, Based on the total weight of the polyalkyl methacrylate copolymer.

C ₂₀ -C ₂₄ alkyl homologues are preferred, and C ₂₀ -C ₂₂ alkyl homologs are the most preferred homologues of component (B). Thus, for example, C ₂₀ -C ₂₂ alkyl homologs may comprise from about 2.0 to about 40.0, from about 4.0 to about 40.0, or from about 4.0 to about 30.0 wt.% Of the obtained polyalkyl methacrylate copolymer. A typical mass of C ₂₀ -C ₂₄ alkyl homologs ranges from about 4.0 to about 40.0, from about 4.0 to about 30.0, or from about 5.0 to about 20.0 wt.% Of the obtained polyalkyl methacrylate copolymer .

The average chain length of the alkyl methacrylate component (B) ranges from about 20 to about 22 carbon atoms or from about 20 to about 21 carbon atoms.

In a preferred embodiment, the sum of components (A) and (B) is equal to 100.0% by weight of the obtained polyalkyl methacrylate copolymer.

The polymethacrylate copolymer DPAs according to the invention may optionally contain C ₁ -C ₁₀ alkyl methacrylate esters or other polymerizable non-alkyl methacrylate monomers.

Polyalkyl methacrylates may consist essentially of monomers (A) and (B). So, for example, the sum of components (A) and (B) is 100%.

Alkyl methacrylate comonomers containing 12 or more carbon atoms in the alkyl ester group are usually prepared according to standard esterification methods using long chain aliphatic alcohols of technical grades. These technically available alcohols are special mixtures of alcohols of variable chain lengths containing from 12 to 30 carbon atoms in alkyl groups. Therefore, taking into account the objectives of the present invention, alkyl methacrylate comonomers not only include, as expected, the individual named alkyl methacrylate esters, but also include mixtures with other alkyl methacrylate esters.

Conventional free radical polymerization methods can be used to prepare the copolymers of the present invention. The polymerization of alkyl methacrylate monomers can occur under a wide variety of conditions, including bulk polymerization, solution polymerization, usually in an organic solvent, preferably in mineral oil.

In solution polymerization, the reaction mixture includes a diluent, alkyl methacrylate monomers, a polymerization initiator, and usually a degree of polymerization regulator and optionally a crosslinking agent.

The diluent may be any inert hydrocarbon liquid. The mass ratio of diluent to the total weight of the monomer may be in the range from about 90:10 to about 60:40. The term "total monomer mass" means the combined amount of all monomers in the original, i.e. unreacted, reaction mixture.

In the preparation of the copolymers of the present invention, the free radical polymerization of the alkyl methacrylate monomers can be polymerized simultaneously or sequentially, or the monomers can be sent to the reaction vessel for some time. So, for example, a mixture of C ₁₂ -C ₃₀ alkyl methacrylate monomers can be sent to the reaction vessel for some time together with the feed initiator.

Suitable polymerization initiators include those that dissociate to form a free radical when heated, for example, a peroxide compound such as benzoyl peroxide, tert-butyl perbenzoate, tert-butyl peroctoate and cumene hydroperoxide; or an azo compound such as azoisobutyronitrile and 2,2'-azobis- (2-methylbutannitrile). The mixture comprises from about 0.01 to about 5.0 wt.% Initiator in terms of the entire monomer mixture. For example, it is possible to use from 0.02 to about 4.0 wt.%, From 0.02 to about 3.5 wt.%. Typically, about 0.02 to about 2.0 wt.% Is used.

Suitable polymerization degree regulators include those common in the art, such as mercaptans and alcohols. So, for example, tridecyl mercaptan, dodecyl mercaptan and ethyl mercaptan can be used as regulators of the degree of polymerization. The choice of the amount of the degree of polymerization regulator to be used is based on the target molecular weight of the synthesized polymer, as well as on the target degree of shear stability of the polymer, i.e. if a more shear-stable polymer is required, more polymerization degree regulator can be added to the reaction mixture. The degree of polymerization regulator is added to the reaction mixture or monomer feed in an amount of from 0.01 to 3.0 wt.% In terms of the monomer mixture.

By way of example and without limitation, to carry out the polymerization reaction, all components are loaded into a reaction vessel, which is equipped with a stirrer, thermometer and reflux condenser, and is kept under stirring in a nitrogen protective atmosphere at a temperature of from about 50 to about 125 ° C for a period of from about 0 5 to about 15 hours

As a product of the above process, a viscous solution of the copolymer of the present invention in a diluent is obtained.

To prepare the lubricating oils of the present invention, the base oil is treated in the usual manner with the copolymer of the invention, i.e. by adding a copolymer to the base oil to obtain a lubricating oil composition having desired low temperature properties. This lubricating oil contains from about 0.01 to about 5.0 wt. frequent., in particular from about 0.01 to about 2.0, more typically from about 0.02 to about 0.5, pure copolymer (i.e. excluding dilution oil) per 100 wt. parts of base oil. The preferred flow rate usually depends, of course, on the base oil.

In a particularly preferred embodiment, the copolymer is added to the base oil in the form of a relatively concentrated solution of the copolymer in a diluent. The diluent oil may be any of the oils listed below that are suitable for use as base oils.

Preferred base oils include mineral oils, poly-alpha olefin synthetic oils, and mixtures thereof. Suitable base oils also include base components obtained by isomerization of synthetic wax and crude paraffin, as well as base components obtained by hydrocracking (rather than solvent extraction) of aromatic and polar components of crude oil. Typically, each of both mineral and synthetic base oils has a kinematic viscosity in the range of from about 1 to about 40 cSt at 100 ° C, although typical applications usually require that each oil has a viscosity in the range of from about 2 to about 20 cSt at 100 ° C.

Mineral oils that can be used in the practice of the present invention include all of the usual base components of mineral oils. They apparently include oils that are naphthenic, paraffinic or aromatic in chemical structure.

Naphthenic oils consist of methylene groups placed in a cyclic formation with paraffin side chains attached to the rings. The pour point is usually lower than the pour point of paraffin oils. Paraffin oils include saturated straight chain or branched hydrocarbons. High molecular weight straight chain paraffins increase the pour point of oils and are often removed by dewaxing. Aromatic oils are semi-unsaturated hydrocarbon rings with closed carbon rings and may have attached side chains. Such oil is more easily degraded than paraffin and naphthalene oils, which leads to the formation of correlated by-products.

The base component typically contains a chemical composition that includes a proportion of all three materials (paraffinic, naphthenic and aromatic). For a discussion of the types of base components, refer to the work of Motor Oils and Engine Lubrication by A. Schilling, Scientific Publications, 1968, sections 2.2-2.5.

The polyalkyl methacrylate copolymer can be used in paraffinic, naphthenic and aromatic oils. For example, the polymethacrylate copolymer can be used in base oils of groups I to V. These groups are known to those skilled in the art. Moreover, the polymethacrylate copolymer can be used in gas-to-liquid oils.

Oils such as gas to liquid (GVG) in the art are known. Gaseous sources include a wide variety of materials, such as natural gas, methane, C ₁ -C ₃ alkanes, landfill gases, and the like. Such gases can be converted into liquid hydrocarbon products suitable for use as a lubricant base oil, by the method of gas into liquid (GVG), such as the method described in US No. 6497812.

Base oils obtained from a gaseous source, hereinafter referred to as "base oils GVZh", as a rule have a viscosity index of more than about 130, sulfur content of less than about 0.3 wt.%, Include more than about 90 wt.% Of saturated hydrocarbons (isoparaffins), typically from about 95.0 to about 100.0 wt.% branched aliphatic hydrocarbons, have a pour point lower than -15 to 20 ° C.

Base oils can be mixed with more conventional base oils, such as those defined by the American Petroleum Institute, Groups I to V. Thus, for example, the base oil component of the lubricating compositions may include from 1 to 100 wt.% Of the base oil of the base.

The lubricating oil composition can at least partially be prepared from a gaseous source and contain the proposed polymethacrylate ester as a depressant.

The oils can be refined according to the usual methodology using acid, alkali and clay or other agents, such as aluminum chloride, or they can be extracted oils obtained, for example, by solvent extraction using solvents such as phenol, sulfur dioxide, furfural, dichlorodiethyl ether, etc. They can be hydrotreated, dewaxed by flash cooling or catalytic dewaxing, or hydrocracked. Mineral oil can be obtained from natural raw sources or prepared from isomerized wax materials or residues from other refining processes. Preferred synthetic oils are α-olefin oligomers, preferably 1-decene oligomers, also known as poly-alpha olefins (P-a-O).

Base oils can be obtained from refined, refined oils or mixtures thereof. Crude oils are obtained directly from a natural source or synthetic source (for example, coal, shale or tar sandstones) without further purification or processing. Examples of crude oils include shale oil obtained directly from a distillation process in a retort, petroleum oil obtained directly from a distillation process, or synthetic ester oil obtained directly from an esterification process, each of which is then used without further processing. Refined oils are similar to crude oils, except that refined oils are pretreated at one or more stages of refining to improve one or more properties. Suitable purification methods include distillation, hydrotreating, dewaxing, solvent extraction, acid or base extraction, filtering and straining, which are all known to those skilled in the art. Re-refined oils are obtained by treating spent oils in processes similar to those carried out to obtain refined oils. These refined oils are also known as regenerated or refined oils, and often additionally processed by methods for removing spent additives and oil degradation products.

It is possible to add at least one additional conventional oil additive to the composition. Mentioned lubricating compositions, for example, greases, gear lubricants, metalworking emulsions and working fluids, may further include other additives that add to further improve their basic properties. Such additives include additional antioxidants, metal passivators, corrosion inhibitors, “index” additives, additional depressant additives, dispersants, detergents, additional high pressure additives and antiwear additives. Such additives are added in amounts conventional for each of them, which in each case are in the range from about 0.01 to 10.0%, preferably from 0.1 to 1.0%, by weight. Examples of additional additives are presented below.

1. Examples of phenolic antioxidants

1.1 Alkylated monophenols: 2,6-ditret-butyl-4-methylphenol, 2-butyl-4,6-dimethylphenol, 2,6-ditret-butyl-4-ethylphenol, 2,6-ditret-butyl-4-n- butylphenol, 2,6-ditret-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2- (alpha-methylcyclohexyl) -4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2, 4,6-tricyclohexylphenol, 2,6-ditret-butyl-4-methoxymethylphenol, linear nonylphenols or nonylphenols branched in the side chain, such as 2,6-dinonyl-4-methylphenol, 2,4-dimethyl-6- (1 '-methylundec-1'-yl) phenol, 2,4-dimethyl-6- (1'-methylheptadec-1'-yl) phenol, 2,4-dimethyl-6- (1'-methyltride-1'-yl )phenol and mixtures thereof.

1.2. Alkylthiomethylphenols: 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-didodecylthiomethyl-4-nonylphenol.

1.3. Hydroquinones and alkylated hydroquinones: 2,6-ditret-butyl-4-methoxyphenol, 2,5-ditret-butylhydroquinone, 2,5-ditret-amylhydroquinone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-ditret-butylhydroin , 2,5-ditret-butyl-4-hydroxyanisole, 3,5-ditret-butyl-4-hydroxyanisole, 3,5-ditret-butyl-4-hydroxyphenyl stearate, bis (3,5-ditret-butyl-4- hydroxyphenyl) adipate.

1.4. Tocopherols: alpha, beta, gamma or delta tocopherol and mixtures thereof (vitamin E).

1.5. Hydroxylated thiodiphenyl ethers: 2,2'-thiobis- (6-tert-butyl-4-methylphenol), 2,2'-thiobis- (4-octylphenol), 4,4'-thiobis- (6-tert-butyl -3-methylphenol), 4,4'-thiobis- (b-tert-butyl-2-methylphenol), 4,4'-thiobis- (3,6-divtor-amylphenol), 4,4'-bis- ( 2,6-dimethyl-4-hydroxyphenyl) disulfide.

1.6. Alkylidenebisphenols: 2,2'-methylenebis- (6-tert-butyl-4-methylphenol), 2,2'-methylenebis- (6-tert-butyl-4-ethylphenol), 2,2'-methylenebis- [4- methyl 6- (alpha-methylcyclohexyl) phenol], 2,2'-methylenebis- (4-methyl-6-cyclohexylphenol), 2,2'-methylenebis- (6-nonyl-4-methylphenol), 2,2 ' -methylenebis- (4,6-ditret-butylphenol), 2,2'-ethylidenebis- (4,6-ditret-butylphenol), 2,2'-ethylidenebis- (6-tert-butyl-4-isobutylphenol), 2 , 2'-methylenebis- [6- (alpha-methylbenzyl) -4-nonylphenol], 2,2'-methylenebis- [6- (alpha, alpha-dimethylbenzyl) -4-nonylphenol], 4,4'-methylenebis- (2,6-ditret-butylphenol), 4,4'-methylenebis- (6-tert-butyl-2-methylphenol), 1,1-bis- (5-tre t-butyl-4-hydroxy-2-methylphenyl) butane, 2,6-bis- (3-tert-butyl-5-methyl-2-hydroxybenzyl) -4-methylphenol, 1,1,3-tris- (5 tert-butyl-4-hydroxy-2-methylphenyl) butane, 1,1-bis- (5-tert-butyl-4-hydroxy-2-methylphenyl) -3-n-dodecylmercaptobutane, ethylene glycolbis- [3,3- bis- (3'-tert-butyl-4'-hydroxyphenyl) butyrate], bis- (3-tert-butyl-4-hydroxy-5-methylphenyl) dicyclopentadiene, bis- [2- (3'-tert-butyl- 2'-hydroxy-5'-methylbenzyl) -6-tert-butyl-4-methylphenyl] terephthalate, 1,1-bis- (3,5-dimethyl-2-hydroxyphenyl) butane, 2,2-bis- (3 , 5-ditret-butyl-4-hydroxyphenyl) propane, 2,2-bis- (5-tert-butyl-4-hydroxy-2-methidphenyl) -4-n-dod ecyl mercaptobutane, 1,1,5,5-tetra (5-tert-butyl-4-hydroxy-2-methylphenyl) pentane.

1.7. O-, N- and S-benzyl compounds: 3,5,3 ', 5'-tetratret-butyl-4,4'-dihydroxydibenzyl ether, octadecyl-4-hydroxy-3,5-dimethylbenzyl mercaptoacetate, tridecyl-4- hydroxy-3,5-ditret-butylbenzyl mercaptoacetate, tris- (3,5-ditret-butyl-4-hydroxybenzyl) amine, bis- (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiotherephthalate, bis- (3,5-Ditret-butyl-4-hydroxybenzyl) sulfide, isooctyl-3,5-ditret-butyl-4-hydroxybenzyl mercaptoacetate.

1.8. Hydroxybenzylated malonates: dioctadecyl-2,2-bis- (3,5-ditret-butyl-2-hydroxybenzyl) malonate, dioctadecyl-2- (3-tert-butyl-4-hydroxy-5-methylbenzyl) malonate, didodecylmercaptoethyl-2 , 2-bis- (3,5-ditret-butyl-4-hydroxybenzyl) malonate, di [4- (1,1,3,3-tetramethylbutyl) phenyl] -2,2-bis- (3,5-ditret -butyl-4-hydroxybenzyl) malonate.

1.9. Aromatic hydroxybenzyl compounds: 1,3,5-tris- (3,5-ditret-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,4-bis- (3,5-ditret-butyl-4 -hydroxybenzyl) -2,3,5,6-tetramethylbenzene, 2,4,6-tris- (3,5-ditret-butyl-4-hydroxybenzyl) phenol.

1.10. Triazine compounds: 2,4-bisctyl mercapto-6- (3,5-ditret-butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octyl mercapto-4, b-bis- (3,5-ditret- butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octyl mercapto-4,6-bis- (3,5-ditret-butyl-4-hydroxyphenoxy) -1,3,5-triazine, 2,4 6-tris- (3,5-ditret-butyl-4-hydroxyphenoxy) -1,2,3-triazine, 1,3,5-tris- (3,5-ditret-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris- (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 2,4,6-tris- (3,5-ditret-butyl-4-hydroxyphenylethyl) -1 3,5-triazine, 1,3,5-tris- (3,5-ditret-butyl-4-hydroxyphenylpropionyl) hexahydro-1,3,5-triazine, 1,3,5-tris- (3,5 dicyclic ogeksil-4-hydroxybenzyl) isocyanurate.

1.11. Acylaminophenols: 4-hydroxylauric acid anilide, 4-hydroxystearic acid anilide, N- (3,5-ditret-butyl-4-hydroxyphenyl) carbamic acid octyl ester.

1.12. Esters of beta- (5-tert-butyl-4-hydroxy-3-methylphenyl) propionic acid and polyhydric alcohols, for example 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol , triethylene glycol, pentaerythritol, tris- (hydroxyethyl) isocyanurate, N, N'-bis- (hydroxyethyl) oxalic acid, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-2, 7-trioxabicyclo [2.2.2] octane.

1.13. Esters of beta- (3,5-ditret-butyl-4-hydroxyphenyl) propionic acid, gamma- (3,5-dicyclohexyl-4-hydroxyphenyl) propionic acid, 3,5-ditret-butyl-4-hydroxyphenylacetic acid and mono- and polyhydric alcohols, for example methanol, ethanol, n-octanol, isooctanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thioethylene glycol, diethylene glycol, triethylene glycol hydroxyethyl) isocyanurate, diamide N, N'-bis- (hydroxyethyl) oxalic acid, 3-tiaundecanol, 3-thiapentadecanol, trimethy lhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo [2.2.2] octane.

1.14. Amides of beta- (3,5-ditret-butyl-4-hydroxyphenyl) propionic acid: N, N'-bis- (3,5-ditret-butyl-4-hydroxyphenylpropionyl) hexamethylenediamine, N, N'-bis- (3 , 5-Ditret-butyl-4-hydroxyphenylpropionyl) trimethylenediamine, N, N'-bis- (3,5-ditret-butyl-4-hydroxyphenylpropionyl) hydrazine.

1.15. Ascorbic acid (vitamin C).

1.16. Amine antioxidants: N, N'-diisopropyl-p-phenylenediamine, N, N'-divtor-butyl-p-phenylenediamine, N, N'-bis- (1,4-dimethylpentyl) -p-phenylenediamine, N, N ' -bis- (1-ethyl-3-methylpentyl) -p-phenylenediamine, N, N'-bis- (1-methylheptyl) -p-phenylenediamine, N, N'-dicyclohexyl-p-phenylenediamine, N, N'- diphenyl-p-phenylenediamine, N, N'-di (naphth-2-yl) -p-phenylenediamine, N-isopropyl-N-phenyl-p-phenylenediamine, N- (1,3-dimethylbutyl) -N'-phenyl p-phenylenediamine, N- (1-methylheptyl) -N'-phenyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, 4- (p-toluenesulfonamido) diphenylamine, N, N'-dimethyl -N, N'-divtor-butyl-p-phenylenediamine, d phenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, 4-n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4-octadecanoylaminophenol, di (4-methythenylphenyl) dimethylaminomethylphenol, 2,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, N, N, N ', N'-tetramethyl-4,4'-diaminodiphenylmethane, 1,2-di - [(2-methylphenyl) amino] ethane , 1,2-di (phenylamino) propane, (o-tolyl) biguanide, di [4- (1 ', 3'-dimethylbutyl) phenyl] amine, tert-octylated N-phenyl-1-naphthylamine, a mixture of mono- and dialkylated tert-butyl / tert-octyldiphenylamines, mixture m it- and dialkylated nonyldiphenylamines, a mixture of mono- and dialkylated dodecyldiphenylamines, a mixture of mono- and dialkylated isopropyl / isohexyl diphenylamines, a mixture of mono- and dialkylated tert-butyl diphenylamines, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzazi , phenothiazine, a mixture of mono- and dialkylated tert-butyltret-octylphenothiazines, mixtures of mono- and dialkylated tert-octylphenothiazines, N-allylphenothiazine, N, N, N ', N'-tetraphenyl-1,4-diaminobut-2-ene, N , N-bis- (2,2,6,6-tetramethylpiperidin-4-yl) hexamethylenediamine, bis- (2,2,6, b-tetramethylpiperidin-4-yl) sebac 2,2,6,6-tetramethylpiperidin-4-one, 2,2,6,6-tetramethylpiperidin-4-ol.

2. Examples of other antioxidants: aliphatic or aromatic phosphites, esters of thiodipropionic acid, thiodioacetic acid or a salt of dithiocarbamic acid, 2,2,12,12-tetramethyl-5,9-dihydroxy-3,7,11-trithiatridecane and 2.2, 15,15-tetramethyl-3,12-dihydroxy-3,7,10,14-tetratihexadecane.

3. Examples of metal deactivators, in particular copper

3.1. Benzotriazoles and their derivatives: 2-mercaptobenzotriazole, 2,5-dimercaptobenzotriazole, 4- and 5-alkylbenzotriazoles (for example, tolutriazole) and their derivatives, 4,5,6,7-tetrahydrobenzotriazole, 5,5'-methylenebisbenzotriazole; Mannich bases of benzotriazole or tolutriazole, such as 1- [di (2-ethylhexylaminomethyl)] tolutriazole and 1- [di (2-ethylhexylaminomethyl)] benzotriazole; alkoxyalkylbenzotriazoles, such as 1- (nonyloxymethyl) benzotriazole, 1- (1-butoxyethyl) benzotriazole and 1- (1-cyclohexyloxybutyl) tolutriazole.

3.2. 1,2,4-Triazoles and their derivatives: 3-alkyl (and aryl) -1,2,4-triazoles, Mannich bases of 1,2,4-triazoles, such as 1- [di (2-ethylhexyl) aminomethyl] -1,2,4-triazole; alkoxyalkyl-1,2,4-triazoles, such as 1- (1-butoxyethyl) -1,2,4-triazole; acylated 3-amino-1,2,4-triazoles.

3.3. Imidazole derivatives: 4,4'-methylenebis- (2-undecyl-5-methylimidazole) and bis [(N-methyl) imidazol-2-yl] carbinol-ethyl ether.

3.4. Sulfur-containing heterocyclic compounds: 2-mercaptobenzothiazole, 2,5-dimercapto-1,3,4-thiadiazole, 2,5-dimercaptobenzothiadiazole and their derivatives; 3,5-bis [di (2-ethylhexyl) aminomethyl] -1,3,4-thiadiazolin-2-one.

3.5. Amine compounds: salicylidene propylene diamine, salicylaminoguanidine and their salts.

4. Examples of corrosion inhibitors

4.1. Organic acids, their esters, metal salts, ammonium salts and anhydrides: alkyl and alkenyl succinic acids and their partial esters with alcohols, diols or hydroxycarboxylic acids, partial amides of alkyl and alkenyl succinic acids, 4-nonylphenoxyacetic acid, alkoxy and alkoxyethoxycarboxylic acids such as dodecyloxyacetic acid, dodecyloxy (ethoxy) acetic acid and their ammonium salts, and in addition, N-oleyl sarcosine, sorbitan monooleate, lead naphthenate, alkenyl succinic anhydrides, for example, dodecenyl succinic anhydride, 2- (2-carbo xyethyl) -1-dodecyl-3-methylglycerol and its salts, in particular sodium salts and triethanolammonium salts.

4.2. Nitrogen-containing compounds

4.2.1 Tertiary aliphatic and cycloaliphatic amines and ammonium salts of organic and inorganic acids, for example oil-soluble alkylammonium carboxylates, and 1- [N, N-bis- (2-hydroxyethyl) amino] -3- (4-nonylphenoxy) propan-2-ol .

4.2.2 Heterocyclic compounds: substituted imidazolines and oxazolines, in particular 2-heptadecenyl-1- (2-hydroxyethyl) imidazoline.

4.2.3. Sulfur-containing compounds: barium dinonylnaphthalene sulfonates, petroleum calcium sulfonates, alkylthio substituted aliphatic carboxylic acids, esters of aliphatic 2-sulfocarboxylic acids and their salts.

5. Examples of "index" additives: polyacrylates, polymethacrylates, nitrogen containing polymethylmethacrylates, vinylpyrrolidone-methacrylate copolymers, polivinilpirrolidiony, polybutenes, polyisobutylenes, olefin copolymers such as ethylene-propylene copolymers, styrene-isoprene copolymers, hydrated styrene-isoprene copolymers, styrene-acrylate copolymers and polyethers. In addition to the products of the present invention, multifunctional viscosity modifiers that also have dispersing and / or antioxidant properties are known and can be used.

6. Examples of depressant additives: polymethacrylates, ethylene-vinyl acetate copolymers, alkyl polystyrenes, fumarate copolymers, alkyl derivatives of naphthalene.

7. Examples of dispersants / surfactants: derivatives of amides and imides of polybutenyl succinic acid and polybutenylphosphonic acid, basic magnesium, calcium and barium sulfonates and phenolates.

8. Examples of high pressure additives and antiwear additives: sulfur and halide compounds, for example chlorinated paraffins, sulfonated olefins or vegetable oils (soybean oil, rapeseed oil), alkyl or aryldi or trisulfides, benzotriazoles or their derivatives, such as bis - (2-ethylhexyl) aminomethyltolutriazoles, dithiocarbamates such as methylenebisdibutyl dithiocarbamate, derivatives of 2-mercaptobenzothiazole, such as 1- [N, N-bis- (2-ethylhexyl) aminomethyl] -2-mercapto-1az-1azol 2,5-dimercapto-1,3,4-thiadiazo derivatives a, such as 2,5-bis (tert-nonilditio) -1,3,4-thiadiazole.

9. Examples of substances to reduce the coefficient of friction: pork olein, oleic acid, tall oil, rapeseed oil, sulfonated solid fats, amines. Other examples are presented in EP-A-0565487.

10. Examples of specific additives for use in oil-water fluids for metalworking and working fluids; emulsifiers: petroleum sulfonates, amines such as polyoxyethylene fatty amines, nonionic surfactants; buffers such as alkanolamines; biocides: triazines, thiazolinones, trisnitromethane, morpholine, sodium pyridinethiol; additives to increase processing speed: calcium and barium sulfonates.

The proposed depressant additive may be mixed with the above directly in the lubricant. It is also possible to prepare a concentrate or the so-called “additive package”, which can be diluted to achieve working concentrations for the intended lubrication.

Lubricating oils containing the copolymers of the present invention can be used in a number of different applications, including automatic transmission fluids, manual gearbox fluids, hydraulic fluids, greases, gear lubricants, metalworking emulsions, motor applications oils and shock absorbing liquids.

An additional embodiment of the invention relates to a method for improving the low-temperature properties of a lubricating oil, which comprises adding a polyalkyl methacrylate copolymer, as described above, of lubricating viscosity to the oil.

EXAMPLES

Example 1: synthesis of lauryl-behenylmethacrylate copolymer (mass ratio of monomers 90/10)

140 g of high-temperature oil (neutral hydrotreated oil) in a nitrogen atmosphere is loaded into the reactor and heated to 95 ° C. 0.406 g of tert-butyl peroctoate in 7.7 g of oil is added to the heated oil in the reactor. For dosing into the reactor, two separate parallel starting materials are supplied. The first starting material was prepared from a mixture of 252.0 g of lauryl methacrylate, 28 g of behenyl methacrylate, 1.12 g of dodecyl mercaptan (DDM) and 235.2 g of high-temperature oil and dosed over a 2-hour period. The second starting material consists of 1.22 g of tert-butyl peroctoate in 23.14 g of oil, it is served over a 3-hour period. The supply of both the first and second source materials begins at the same time. Upon completion of the 2-hour feed, the feed rate of the second starting material, initiator, is doubled. The reaction mixture was kept for an additional hour at 95 ° C, after which an additional portion of initiator, 0.56 g in 10.64 g of oil was added to the reaction mixture, and kept for another hour at 95 ° C. The average chain length of lauryl methacrylate is approximately 12.6 carbon atoms. The average carbon chain length of behenyl methacrylate is approximately 20.3 carbon atoms. The resulting polyalkyl methacrylate (lauryl / behenyl polymethacrylate: 90/10) formed in Example 1 has an average chain length of about 13.4 carbon atoms.

Table I The resulting composition polyalkylmethacrylate copolymer formed in example 1, is: Polymer components In wt.% In terms of the total weight of the copolymer Dodecyl methacrylate 61 Tetradecylmethacrylate 23 Hexadecylmethacrylate 7 Octadecylmethacrylate four Eicosyl methacrylate one Docosyl methacrylate four

Example 2: synthesis of lauryl / C ₃₀ alkyl methacrylate copolymer (mass ratio of monomers: 90/10)

100.0 g of high temperature oil (neutral hydrotreated oil) in a nitrogen atmosphere is loaded into the reactor and heated to 95 ° C. 0.213 g of tert-butyl peroctoate in 4.05 g of oil is added to the heated oil in the reactor. For dosing into the reactor, two separate parallel starting materials are supplied. The first starting material was prepared from a mixture of 180.1 g of lauryl methacrylate, 31.48 g of C ₃₀ alkyl methacrylate, 1.46 g of dodecyl mercaptan (DDM) and 175.8 g of high-temperature oil and dosed over a 2-hour period. The first starting material is also mixed and carefully heated, since at room temperature the C ₃₀ alkyl methacrylate is not completely soluble in the base oil. The second starting material consists of 0.64 g of tert-butyl peroctoate in 12.14 g of oil, it is served over a 3-hour period. The supply of the first and second source materials begins simultaneously. At the end of 2 hours, the feed rate of the second starting material, initiator, is doubled. The reaction mixture was kept for an additional hour at 95 ° C, after which an additional portion of initiator, 0.29 g in 3.61 g of oil was added to the reaction mixture, and kept for another hour at 95 ° C. The average chain length of the C ₃₀ alkyl methacrylate is about 30.4 carbon atoms. The average chain length formed in example 2 polymethacrylate copolymer (lauryl / C ₃₀ alkyl 90/10) is 14.4.

Table II The resulting composition of the polyalkyl methacrylate copolymer formed in example 2 is: The number of carbon atoms in the alkyl chain Wt.% In terms of the total weight of the copolymer 12 65.1 fourteen 21.1 16 4.3 The number of carbon atoms in the alkyl chain Wt.% In terms of the total weight of the copolymer eighteen 0.5 twenty 0.6 22 0.7 24 0.8 26 0.8 28 0.9 thirty 0.8 32 0.8 34 0.7 36 0.7 38 0.5 40 0.4 42 0.3 44 0.3 46 0.2 48 0.1 fifty 0.1 52 0.08 54 0.06 56 0.04 58 0.02

Example 3

Application of data for depressant additives: comparison of viscosities at low temperatures.

Each of the copolymer of Example 1 and a technical depressant is separately added to the hydrotreated mineral oil of group II. The temperature loss and viscosity values are presented in table 3.

Table III Properties 0.2 wt.% DPP in hydrotreated mineral oil of group II. DpP ¹ Pour point [° C] Brookfield Low Temperature Viscosity at -35 ° C [cP] Kinematic viscosity, 40 ° C [cSt] Hydrotreated group II oil -eighteen Too viscous to define 35.48 Comparative ² example -42 (-39) 244000 35.82 Example 1 -45 80600 35.5 1) The compositions of example 1 and comparative example include 40 wt.% Polyalkyl methacrylates in hydrotreated oil. 0.2 wt.% Of this solution is added to the hydrotreated oil to determine the viscosity and pour point. 0.2 wt.% In table 3 represents 0.8 wt.% Of the main substances (copolymer). 2) The composition in accordance with a comparative example includes a commercially available polyalkyl methacrylate copolymer. This polymer is prepared from long chain methacrylate esters (≥C 12).

The pour point in brackets reflects the second experiment of the same test. A commercially available polyalkyl methacrylate copolymer is defined as being alkyl methacrylates with a distribution of mainly C ₁₂ -C ₁₈ . Pyrolysis of GC / MS did not detect the presence of C ₂₂ alkyl methacrylate. Brookfield low temperature viscosity is determined according to ASTM D2983. Kinematic viscosity is determined according to ASTM D445. The pour point is determined according to ASTM D5950. Table 3 shows that the product of example 1 (according to the invention) at low temperatures has a significantly lower viscosity than the commercially available polyalkyl methacrylate.

Claims (9)

1. Polyalkyl methacrylate copolymer to reduce the temperature loss of fluidity of the composition of the mineral oil, including derivatized units from:
(A) from 60.0 to 96.0 wt.% C ₁₂ -C ₁₆ alkyl methacrylate and
(B) from 40.0 to 4.0 wt.% C ₁₈ -C ₃₀ alkyl methacrylate;
moreover, component (B) includes from 40 to 50 wt.% C ₁₈ alkyl methacrylate, from 5 to 15 wt.% C ₂₀ alkyl methacrylate and from 40 to 50 wt.% C ₂₂ alkyl methacrylate, calculated on the total weight of component (B). 2. The copolymer according to claim 1, which has a weight average molecular weight of from 5000 to 250,000. 3. The copolymer according to claim 1, in which component (A) is from 65.0 to 95.0 wt.% The obtained polyalkyl methacrylate copolymer. 4. The copolymer according to claim 1, in which component (B) is from 35.0 to 5.0 wt.% The obtained polyalkyl methacrylate copolymer. 5. The copolymer according to claim 1, in which component (A) is a straight or branched chain methacrylic acid alkyl ester selected from the group consisting of lauryl methacrylate, myristyl methacrylate, cetyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, tetradecyl methacrylate, penta. 6. The copolymer according to claim 1, in which component (B) is a straight-chain or branched methacrylic acid alkyl ester selected from the group consisting of stearyl methacrylate, octadecyl methacrylate, nonadecyl methacrylate, eicosyl methacrylate, genicose acrylate, trimethyl acrylate, acrylate, acrylate, , nonacosyl methacrylate, triacontyl methacrylate, behenyl methacrylate and mixtures thereof. 7. The copolymer according to claim 1, in which component (A) is lauryl methacrylate, and component (B) is behenyl methacrylate. 8. Lubricating composition, including:
(I) lubricating oil;
(II) the polyalkyl methacrylate copolymer according to claim 1 and optional
(Iii) other additives. 9. The lubricating composition of claim 8, in which component (II) is contained in an amount of from 0.01 to about 5 wt. including the main substance of the copolymer per 100 wt. including oil.