Lubricant additive composition

Abstract

The present invention relates to an additive composition and a process for its preparation. The present invention further relates to the use of the additive composition as a lubricant additive in a lubricating oil formulation and to a lubricating oil formulation comprising the additive composition.

Description

Technical Field

[0001] This invention relates to additive compositions and methods for their preparation. The invention also relates to the use of said additive compositions as lubricant additives in lubricating oil formulations and to lubricating oil formulations comprising said additive compositions. Background Technology

[0002] Pour point lowering agents (PPDs) are additives that improve the low-temperature properties of oils by modifying the wax crystallization process. Many chemical types are currently available, including polyalkyl methacrylates, styrene-modified polyesters, alkylated polystyrene, ethylene-vinyl acetate, vinyl acetate-fumarate, styrene-maleic anhydride, and alkylated naphthalenes. In particular, polyalkyl methacrylates are commonly used as PPDs and contain linear C-chain methacrylic acid. 16 Or higher carbon number esters, which can be readily polymerized to obtain polymers capable of interacting with paraffinic substances in base oils.

[0003] US8143202B2 describes a polyalkyl methacrylate having 60 to about 96% by weight of C-methacrylate. 12 -C 16 Alkyl esters and about 4 to about 40% by weight of C methacrylate 18 -C 30 Alkyl esters provide excellent low-temperature performance for lubricants.

[0004] US6255261 describes a poly(meth)acrylate copolymer that can be used as a PPD, comprising about 5 to about 60% by weight of (meth)acrylate C. 11 -C 15 Alkyl ester; and about 40 to about 95% by weight of (meth)acrylic acid C 16 -C 30 Alkyl esters.

[0005] Therefore, to improve the low-temperature performance of oils, PPD (such as those mentioned above) is added to lubricant formulations, and for most formulations, additional viscosity index improvers (VII) are needed to improve the viscosity measurement performance of the lubricant. Therefore, to reduce the number of additive components blended during the manufacture of lubricating oils, additive compositions containing VII and PPD are preferred. However, additive compositions containing VII and PPD may lead to compatibility issues and thus some storage stability problems.

[0006] Therefore, it is of interest to develop an additive composition containing VII and PPD that has good long-term storage properties and can provide both improved low-temperature performance and a high viscosity index for the lubricant formulation to which the composition is added. Summary of the Invention Invention Overview

[0008] Through in-depth research, the inventors of this invention have surprisingly discovered that the additive composition as defined in claim 1 solves the above-mentioned technical problems because it provides a combination of good storage stability as an additive composition, high viscosity index in lubricant formulations, and improved low-temperature performance.

[0009] Therefore, in a first aspect, the present invention relates to the additive composition as defined in claim 1.

[0010] In a second aspect, the present invention relates to a method for preparing the additive composition.

[0011] In a third aspect, the present invention relates to the use of the additive composition as a lubricant additive in a lubricating oil formulation for improving the storage stability, viscosity index and low-temperature performance of the lubricating oil formulation.

[0012] In a fourth aspect, the present invention relates to lubricant formulations comprising additive compositions as defined herein. Invention Details

[0014] The additive composition of the present invention

[0015] In a first aspect, the present invention relates to an additive composition (A) comprising a viscosity index improver (V) and a pour point depressant (P).

[0016] The viscosity index improver (V) described herein has a weight-average molecular weight (M) of 100,000 to 1,000,000 g / mol. w The polymer is a polymer of the following substances, and can be obtained by polymerizing a monomer composition comprising:

[0017] a) Based on the total weight of the viscosity modifier monomer composition, 10 to 30% by weight of one or more polybutadiene-based macromonomers having a number average molecular weight of 500 to 10,000 g / mol.

[0018] b) Based on the total weight of the viscosity improver monomer composition, 50 to 70% by weight of methyl methacrylate, butyl methacrylate, a monomer having 8 to 17 carbon atoms, selected from styrene or substituted styrene having alkyl substituents in the side chain, or mixtures thereof.

[0019] c) Based on the total weight of the viscosity modifier monomer composition, 1 to 15% by weight of a linear or branched (meth)acrylic acid C7-C12 ... 30 A monomer of an alkyl ester, or a mixture thereof;

[0020] The pour point depressant (P) described herein has a weight-average molecular weight (M) of 10,000 to 60,000 g / mol. w The polymer is a polymer of the following substances, and can be obtained by polymerizing a monomer composition comprising:

[0021] e) 20 to 35% by weight of a monomer selected from linear or branched C1-C6 alkyl esters of (meth)acrylic acid, or a mixture thereof, based on the total weight of the monomer composition.

[0022] f) Based on the total weight of the monomer composition, 20 to 75% by weight of a linear or branched C7-C11(meth)acrylic acid. 15 Monomers of alkyl esters

[0023] g) Based on the total weight of the monomer composition, 5 to 60% by weight of at least one linear or branched C-type (meth)acrylic acid. 16 -C 24 Monomers of alkyl esters

[0024] Wherein, based on the total solid polymer content of polymers (V) and (P) in the additive composition, the weight ratio of (V) to (P) is from 99:1 to 80:20.

[0025] Unless otherwise stated, the weight of the monomers is given relative to the total amount of monomers used, i.e., the total weight of the monomer composition used to prepare the polymer.

[0026] Preferably, the viscosity index improver polymer (V) has a weight-average molecular weight (M) of 100,000 to 600,000 g / mol, more preferably 100,000 to 500,000 g / mol, and even more preferably 100,000 to 400,000 g / mol. w ).

[0027] Preferably, the polydispersity index (PDI) of the viscosity index improver (V) according to the present invention is in the range of 1.0 to 6.0, more preferably 2.0 to 5.5, and even more preferably 3.0 to 5.0. The polydispersity index is defined as the ratio of weight-average molecular weight to number-average molecular weight (Mi). w / M n ).

[0028] Preferably, the pour point lowering polymer (P) has a weight-average molecular weight (M) of 15,000 to 60,000 g / mol, more preferably 15,000 to 50,000 g / mol. w ).

[0029] Preferably, the polydispersity index (PDI) of the pour point lowering polymer (P) according to the present invention is in the range of 1.0 to 5.0, more preferably 1.5 to 4.5, and even more preferably 2.0 to 3.0. The polydispersity index is defined as the ratio of weight-average molecular weight to number-average molecular weight (Mi). w / M n ).

[0030] In this invention, the weight-average molecular weight (M) of the polymer (pour point depressant (P) and viscosity index improver (V)) is... w The result was determined by gel permeation chromatography (GPC) using polymethyl methacrylate (PMMA) calibration standards under the following measurement conditions:

[0031] Eluent: Tetrahydrofuran (THF)

[0032] Operating temperature: 40℃

[0033] Column assembly: This column assembly consists of one pre-column (PSS-SDV) 10μm 8.0×50mm) and three columns (2×PSS-SDV Linear XL 10μm 8.0×300mm, 1×PSS-SDV) Composed of 10μm (8.0×300mm), all columns have an average particle size of 10μm (PSS Standards Service GmbH, Mainz, Germany).

[0034] Flow rate: 1 mL / min

[0035] Injection volume: 100μL

[0036] Instrument: Shodex GPC101, which consists of an autosampler, pump, and column oven.

[0037] Detection device: a refractive index detector obtained from Shodex.

[0038] In the context of this invention, the term "(meth)acrylic acid" refers to acrylic acid, methacrylic acid, and mixtures of acrylic acid and methacrylic acid; preferably methacrylic acid. The term "(meth)acrylate" refers to an ester of acrylic acid, an ester of methacrylic acid, or a mixture of esters of acrylic acid and methacrylic acid; preferably an ester of methacrylic acid.

[0039] Preferably, the additive composition (A) contains at least 25% by weight of solid polymer based on the total weight of polymers (P) and (V) in the additive composition (A).

[0040] Preferably, the amount of monomer e) is 25 to 30% by weight based on the total weight of the monomer composition of the pour point lowering agent (P). The monomer e) is selected from methyl methacrylate, butyl methacrylate, or mixtures thereof, preferably methyl methacrylate.

[0041] Preferably, the amount of monomer f) is 20 to 60% by weight, more preferably 25 to 55% by weight, based on the total weight of the monomer composition of the pour point lowering agent (P).

[0042] Preferably, the amount of monomer (g) is 20 to 50% by weight, more preferably 25 to 50% by weight, based on the total weight of the monomer composition of the pour point lowering agent (P).

[0043] Preferably, the total amount of monomers e), f) and g) in the monomer composition of the pour point lowering agent (P) is 95 to 100% by weight based on the total weight of the monomer composition of the pour point lowering agent (P), preferably up to 100% by weight.

[0044] Preferably, the amount of monomer a) is 15 to 30% by weight, more preferably 15 to 29% by weight, based on the total weight of the monomer composition of the viscosity index improver (V).

[0045] Preferably, the amount of monomer b) is 55 to 70% by weight based on the total weight of the monomer composition of the viscosity index improver (V).

[0046] The monomer b) according to the invention is selected from methyl (meth)acrylate, butyl (meth)acrylate, a monomer having 8 to 17 carbon atoms selected from styrene or substituted styrene having alkyl substituents in the side chain, or mixtures thereof. Suitable styrene monomers having 8 to 17 carbon atoms are selected from styrene, substituted styrene having alkyl substituents in the side chain, such as α-methylstyrene and α-ethylstyrene, substituted styrene having alkyl substituents on the ring, such as vinyltoluene and p-methylstyrene, halostyrene, such as monochlorostyrene, dichlorostyrene, tribromostyrene and tetrabromostyrene, nitrostyrene; preferably styrene.

[0047] Preferably, the monomer c) is selected from linear C of methacrylic acid. 12-14 Alkyl esters, straight-chain C-methyl methacrylate 16-18 Alkyl esters or mixtures thereof, more preferably mixtures thereof.

[0048] Preferably, the monomer composition of the viscosity index improver (V) further comprises 0 to 20% by weight, more preferably 0.1 to 20% by weight, even more preferably 0.1 to 15% by weight, and most preferably 0.1 to 10% by weight of monomer d), which is selected from (meth)acrylates of ether alcohols, aminoalkyl (meth)acrylates, aminoalkyl (meth)acrylamides, or mixtures thereof.

[0049] Preferably, the total amount of monomers a), b), c) and d) in the monomer composition of the viscosity index improver (V) is 95 to 100% by weight based on the total weight of the monomer composition of the viscosity index improver, preferably up to 100% by weight.

[0050] The polybutadiene-based macromonomer a) of the present invention is an ester of (meth)acrylic acid, which is either a reaction product of an ester of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene (by transesterification), or a reaction product of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene (by direct esterification).

[0051] In the context of this invention, polymer (V) comprises a first polymer, also referred to as the backbone or main chain, and a plurality of other polymers, referred to as side chains, covalently bonded to the main chain. In this case, the main chain of the polymer is formed by interconnected unsaturated groups of the mentioned (meth)acrylate. The alkyl groups of the (meth)acrylate and hydrogenated polybutadiene chains form the side chains of the polymer. The reaction product formed by an ester of (meth)acrylate and a hydroxylated hydrogenated polybutadiene, or the reaction product formed by an ester of (meth)acrylate and a hydroxylated hydrogenated polybutadiene, corresponds to monomer a), and is also referred to in this invention as a macromonomer or polybutadiene-based macromonomer a).

[0052] The viscosity index improver polymer (V) according to the present invention can be based on its molar branching degree (“f”). 支化 The molar branching degree is characterized by the percentage of the macromonomer (monomer a) used, expressed in mol%, based on the total molar amount of all monomers in the monomer composition. The molar amount of the macromonomer used is based on the number-average molecular weight M of the macromonomer. n The calculation of the molar branching degree is described in detail in WO2007 / 003238A1, especially on pages 13 and 14, which is explicitly cited here.

[0053] Preferably, the polymer has a molar branching degree f of 0.1 to 5 mol%, more preferably 0.5 to 4 mol%, and most preferably 1.0 to 2.5 mol%. 支化 .

[0054] macromonomers a)

[0055] According to the present invention, the monomer composition of the polymer (V) comprises, as monomer a), 10 to 30% by weight, preferably 10 to 29% by weight, more preferably 15 to 29% by weight, of a polybutadiene-based macromonomer having a number average molecular weight (Mn) of 500 to 10,000 g / mol. n ).

[0056] Preferably, the polybutadiene-based macromonomer a) used according to the present invention has a number-average molecular weight (M) of 1,000 to 6,000 g / mol, more preferably 1,500 to 5,500 g / mol. n ).

[0057] The number-average molecular weight (M) of the macromonomer n The determination was performed by gel permeation chromatography (GPC) using polybutadiene calibration standards (PSS Standards Service GmbH, Mainz, Germany) according to DIN 55672-1 under the following measurement conditions:

[0058] Eluent: Tetrahydrofuran (THF)

[0059] Operating temperature: 35℃

[0060] Column assembly: This column assembly consists of one pre-column (PSS-SDV; 10μm; 8×50mm), four PSS-SDV columns (SDV-LXL, SDV-LinL) with dimensions of 300×8mm and an average particle size of 10μm, and two SDV columns. (PSSSstandards Service GmbH, Mainz, Germany) and a solvent peak separation column with a size of 8×100 mm (KF-800D from Shodex).

[0061] Flow rate: 1 mL / min

[0062] Injection volume: 100μL

[0063] Instrument: Agilent 1100 series, consisting of an autosampler, pump, and column oven; Detection device: refractive index detector from the Agilent 1100 series.

[0064] Preferably, the hydroxylated hydrogenated polybutadiene has a hydrogenation level of at least 99%. An alternative measure of the hydrogenation level that can be determined for the polymers of the present invention is the iodine value. The iodine value refers to the number of grams of iodine that can be added to 100g of the polymer. Preferably, the polymers of the present invention have an iodine value of no more than 5g of iodine per 100g of polymer. The iodine value is determined according to DIN 53241-1:1995-05 by the Wijs method.

[0065] Preferred hydroxylated hydrogenated polybutadiene can be obtained according to GB 2270317.

[0066] As used herein, the term "hydroxylated hydrogenated polybutadiene" refers to hydrogenated polybutadiene containing one or more hydroxyl groups. The hydroxylated hydrogenated polybutadiene may further include additional structural units, such as those derived from polyether groups added to polybutadiene with an epoxide, or from maleic anhydride groups added to polybutadiene. These additional structural units can be introduced into the polybutadiene when it is functionalized with hydroxyl groups.

[0067] Hydrogenated polybutadiene with monohydroxylation is preferred. More preferably, the hydrogenated polybutadiene with hydroxylation is hydroxyethyl- or hydroxypropyl-terminated hydrogenated polybutadiene. Hydroxypropyl-terminated polybutadiene is particularly preferred.

[0068] These monohydroxylated hydrogenated polybutadienes can be prepared by the following process: first, butadiene monomers are converted into polybutadiene via anionic polymerization. Subsequently, hydroxylated polybutadienes can be prepared by reacting the polybutadiene monomers with an alkylene oxide, such as ethylene oxide or propylene oxide. The polybutadiene can also react with more than one alkylene oxide unit, resulting in a polyether-polybutadiene block copolymer with terminal hydroxyl groups. The hydroxylated polybutadienes can be hydrogenated in the presence of a suitable transition metal catalyst.

[0069] These monohydroxylated hydrogenated polybutadienes may also be selected from products obtained by hydroboration of (co)polymers having terminal double bonds (e.g., those described in U.S. Patent 4,316,973); maleic anhydride-ene-amino alcohol adducts obtained by the reaction of (co)polymers having terminal double bonds and an ene between maleic anhydride and an amino alcohol; and products obtained by hydroformylation of (co)polymers having terminal double bonds and subsequent hydrogenation (e.g., those described in Japanese Publication S63-175096).

[0070] The macromonomer a) used according to the present invention can be prepared by transesterification of an alkyl methacrylate. The alkyl methacrylate reacts with the hydroxylated hydrogenated polybutadiene to form the ester of the present invention. Methyl methacrylate or ethyl methacrylate is preferably used as a reactant.

[0071] This type of transesterification is widely known. For example, heterogeneous catalyst systems such as lithium hydroxide / calcium oxide mixtures (LiOH / CaO), pure lithium hydroxide (LiOH), lithium methoxide (LiOMe), or sodium methoxide (NaOMe) can be used for this purpose, or homogeneous catalyst systems such as isopropyl titanate (Ti(OiPr)4) or dioctyltin oxide (Sn(OCt)2O) can be used. The reaction is an equilibrium reaction. Therefore, the released low molecular weight alcohol is typically removed, for example, by distillation.

[0072] Furthermore, the macromonomer can be obtained by direct esterification, for example, preferably by starting with (meth)acrylic acid or (meth)acrylic anhydride under acidic catalysis of p-toluenesulfonic acid or methanesulfonic acid, or by starting with free methacrylic acid via the DCC method (dicyclohexylcarbodiimide).

[0073] In addition, the hydroxylated hydrogenated polybutadiene of the present invention can be converted into an ester by reacting with an acyl chloride (e.g., (meth)acryloyl chloride).

[0074] Preferably, in the preparation of the esters of the present invention as detailed above, polymerization inhibitors, such as 4-hydroxy-2,2,6,6-tetramethylpiperidinoxy radicals and / or hydroquinone monomethyl ether, are used.

[0075] Monomer c)

[0076] Regarding monomer c), the term "(meth)acrylic acid C" 7-30 "Alkyl ester" refers to a (meth)acrylate with a straight or branched alkyl chain having 7 to 30 carbon atoms. The term includes (meth)acrylates formed individually with an alcohol of a specific length, and also includes mixtures of (meth)acrylates formed with alcohols of different lengths.

[0077] Suitable (meth)acrylic acid C 7-30Alkyl esters include, for example, 2-butyloctyl (meth)acrylate, 2-hexyloctyl (meth)acrylate, decyl (meth)acrylate, 2-butyldecyl (meth)acrylate, 2-hexyldecyl (meth)acrylate, 2-octyldecyl (meth)acrylate, undecyl (meth)acrylate, 5-methylundecyl (meth)acrylate, dodecyl (meth)acrylate, 2-methyldodecyl (meth)acrylate, 2-hexyldodecyl (meth)acrylate, 2-octyldodecyl (meth)acrylate, tridecyl (meth)acrylate, 5-methyltridecyl (meth)acrylate, tetradecyl (meth)acrylate, 2-decyltetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, 2-methylhexadecyl (meth)acrylate, 2-dodecylhexadecyl (meth)acrylate, heptadecanyl (meth)acrylate, 5-isopropylheptadecanyl (meth)acrylate, 4-tert-butyloctadecyl (meth)acrylate, and so on. 5-Ethyloctadecyl acrylate, 3-Isopropyloctadecyl (meth)acrylate, octadecyl (meth)acrylate, 2-Decyloctadecyl (meth)acrylate, 2-Tetradecyl (meth)acrylate, nonadecanyl (meth)acrylate, eicosyl (meth)acrylate, cetyl eicosyl (meth)acrylate, stearyl eicosyl (meth)acrylate, dodecyl (meth)acrylate, eicosyl tritetradecyl (meth)acrylate, 2-Decyl-tetradecyl (meth)acrylate, 2-Decyl-octadecyl (meth)acrylate, 2-Dodecyl-1-hexadecyl (meth)acrylate, 1,2-Octyl-1-dodecyl (meth)acrylate, 2-Tetradecyl (meth)acrylate, 1,2-Tetradecyl-octadecyl (meth)acrylate, and 2-Hexadecyl-eicosyl (meth)acrylate, n-tetradecyl (meth)acrylate, n-triacyl (meth)acrylate, and / or n-hexadecyl (meth)acrylate.

[0078] The term "(meth)acrylic acid C" 12-14 "Alkyl ester" refers to an ester formed from (meth)acrylic acid and a straight-chain or branched alcohol having 12 to 14 carbon atoms. The term includes individual (meth)acrylates formed with alcohols of a specific length, and also includes mixtures of (meth)acrylates formed with alcohols of varying lengths. Suitable (meth)acrylic acid C 12-14 Alkyl esters include, for example, dodecyl methacrylate, 2-methyldodecyl methacrylate, tridecyl methacrylate, 5-methyltridecyl methacrylate and / or tetradecyl methacrylate.

[0079] Similarly, (meth)acrylic acid C 16-18Alkyl esters include, for example, those independently selected from: hexadecyl (meth)acrylate, 2-methylhexadecyl (meth)acrylate, heptadecanyl (meth)acrylate, 5-isopropylheptadecanyl (meth)acrylate, 4-tert-butyloctadecyl (meth)acrylate, 5-ethyloctadecyl (meth)acrylate, 3-isopropyloctadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecanyl (meth)acrylate, eicosyl (meth)acrylate, cetyl eicosyl (meth)acrylate, stearyl eicosyl (meth)acrylate, dodecyl (meth)acrylate, benzyl (meth)acrylate, eicosyl tritetradecyl (meth)acrylate, cycloalkyl (meth)acrylate, 2,4,5-tri-tert-butyl-3-vinylcyclohexyl (meth)acrylate, and 2,3,4,5-tetra-tert-butylcyclohexyl (meth)acrylate. Particularly preferred is C(meth)acrylate. 16-18 The alkyl ester is stearyl eicosyl ester of (meth)acrylate.

[0080] The particularly preferred monomer c) is a linear C 12-14 (Meth)acrylates (C methacrylate) of alcohol mixtures 12-14 Alkyl esters), straight-chain C 16-18 (Meth)acrylates (C methacrylate) of alcohol mixtures 16-18 Alkyl esters or mixtures thereof.

[0081] Monomer e)

[0082] The monomer composition of the pour point lowering agent (P) according to the present invention comprises 0 to 35% by weight of a monomer selected from linear or branched C1-C6 alkyl esters of (meth)acrylic acid or a mixture thereof.

[0083] Examples of C1 to C6 alkyl ester monomers of (meth)acrylate (wherein the straight-chain or branched alkyl group contains 1 to 6 carbon atoms) are methyl methacrylate (MMA), methyl acrylate and ethyl acrylate, propyl methacrylate, butyl methacrylate (BMA) and butyl acrylate (BA), isobutyl methacrylate (IBMA), hexyl methacrylate and cyclohexyl methacrylate, cyclohexyl acrylate and combinations thereof. The most preferred C1 to C6 alkyl ester monomer of (meth)acrylate is methyl methacrylate.

[0084] Monomer f)

[0085] The monomer composition of the pour point lowering polymer (P) according to the present invention comprises 20 to 95% by weight, preferably 25 to 95% by weight, of (meth)acrylic acid linear or branched C7-C based on the total weight of the monomer composition. 15 A monomer of an alkyl ester. Preferred (meth)acrylic acid is C7 to C8. 15Alkyl esters are (meth)acrylic acid C 12 To C 14 Alkyl esters.

[0086] The (meth)acrylic acid C7 to C 15 Examples of alkyl ester monomers (wherein the straight-chain or branched alkyl group contains 7 to 15 carbon atoms) are 2-ethylhexyl acrylate (EHA), 2-ethylhexyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, isodecyl methacrylate (IDMA, based on a mixture of branched (C10) alkyl isomers), undecyl methacrylate, dodecyl methacrylate (also known as lauryl methacrylate), tridecyl methacrylate, tetradecyl methacrylate (also known as myristyl methacrylate), pentadecyl methacrylate, and mixtures thereof. More preferably, (meth)acrylic acid C7 to C10 isomers are preferred. 15 The alkyl ester monomers are dodecyl-pentadecanyl methacrylate (DPMA); mixtures of straight-chain and branched isomers of dodecyl, tridecyl, tetradecyl, and pentadecyl methacrylates; decyl-octyl methacrylate (DOMA), mixtures of decyl and octyl methacrylates; nonyl-undecyl methacrylate (NUMA), mixtures of nonyl, decyl, and undecyl methacrylates; and lauryl-myristyl methacrylate (LMA), mixtures of dodecyl and tetradecyl methacrylates. Preferred (meth)acrylates are C7 to C6. 15 The alkyl ester is lauryl-myristyl methacrylate (LMA).

[0087] monomer g)

[0088] The monomer composition of the pour point lowering polymer according to the invention comprises 5 to 60% by weight, preferably 5 to 50% by weight, of a monomer selected from linear or branched C-methacrylic acid based on the total weight of the monomer composition. 16 -C 24 At least one monomer of an alkyl ester.

[0089] (Meth)acrylic acid C 16 To C 24 Examples of alkyl ester monomers (wherein the straight-chain or branched alkyl group contains 16 to 24 carbon atoms) are hexadecyl methacrylate (also known as cetyl methacrylate), heptadecanyl methacrylate, octadecyl methacrylate (also known as stearyl methacrylate), nonadecanyl methacrylate, eicosyl methacrylate, benzyl methacrylate, and mixtures thereof. More preferably, (meth)acrylic acid C 16 To C 24The alkyl ester monomers are: cetyl-eicosyl methacrylate (CEMA), a mixture of hexadecyl methacrylate, octadecyl methacrylate, and eicosyl methacrylate; cetyl-stearyl methacrylate (SMA), or a mixture of hexadecyl methacrylate and octadecyl methacrylate. The most preferred (meth)acrylate is C... 16 To C 24 The alkyl ester is selected from cetyl-eicosyl methacrylate (CEMA), cetyl-stearyl methacrylate (SMA), or mixtures thereof.

[0090] Preparation method of additive composition according to the present invention

[0091] The present invention also relates to a method for preparing the additive composition (A) according to the present invention, wherein the method comprises the following steps:

[0092] (x) A viscosity index improver (V) is prepared by providing a monomer composition as defined in the “Additive Compositions of the Invention” section above and initiating free radical polymerization in the monomer composition to prepare a polymer (V).

[0093] (y) A pour point lowering agent (P) is prepared by providing a monomer composition as defined in the “Additive Compositions of the Invention” section above and initiating free radical polymerization in the monomer composition to prepare a polymer (P).

[0094] (z) The viscosity index improver polymer (V) is mixed with the pour point decreaser polymer (P) to provide an additive composition (A) according to the invention.

[0095] Standard free radical polymerization is described in particular in detail in Ullmann's Encyclopedia of Industrial Chemistry, sixth edition. Generally, a polymerization initiator is used for this purpose, and chain transfer agents are optionally used.

[0096] The ATRP method itself is known. It is presumably a type of "living" radical polymerization, but this is not intended to be limited by a description of the mechanism. In these methods, a transition metal compound is reacted with a compound having transferable atomic groups. This involves the transfer of the transferable atomic groups to the transition metal compound, resulting in the oxidation of the metal. The reaction forms a radical that adds to an olefinic group. However, the transfer of the atomic groups to the transition metal compound is reversible, and therefore the atomic groups transfer back to the growing polymer chain, leading to the formation of a controlled polymerization system. Thus, the formation, molecular weight, and molecular weight distribution of the polymer can be controlled.

[0097] This reaction scheme is described, for example, by J.-S. Wang et al., J. Am. Chem. Soc., Vol. 117, pp. 5614-5615 (1995), and by Matyjaszewski, Macromolecules, Vol. 28, pp. 7901-7910 (1995). Furthermore, variations of the ATRP described above are disclosed in patent applications WO 96 / 30421, WO 97 / 47661, WO 97 / 18247, WO 98 / 40415, and WO 99 / 10387. Additionally, the polymers of the present invention can also be obtained, for example, via the RAFT method. This method is described in detail, for example, in WO 98 / 01478 and WO 2004 / 083169.

[0098] The polymerization can be carried out under standard pressure, reduced pressure, or increased pressure. The polymerization temperature is not critical. However, it is generally within the range of -20 to 200°C, preferably 50 to 150°C, and more preferably 80 to 130°C.

[0099] Preferably, the oil used to dilute the monomer composition of polymer (V) or polymer (P) is an API Group I, II, III, IV or V oil, or a mixture thereof. Preferably, a Group III oil or a mixture thereof is used to dilute the monomer composition.

[0100] Preferably, the polymerization step of polymer (V) or polymer (P) includes the addition of a free radical initiator.

[0101] Suitable free radical initiators include azo initiators such as azobisisobutyronitrile (AIBN), 2,2'-azobis(2-methylbutyronitrile) (AMBN), and 1,1-azobiscyclohexanenitrile, and peroxides such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauroyl peroxide, tert-butyl peroxy-2-ethylhexanoate, ketone peroxide, tert-butyl peroctanoate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, benzoyl peroxide, etc. tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, 2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate, dicumyl peroxide, 1,1-bis(tert-butylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, cumyl hydroperoxide, tert-butyl hydroperoxide, and bis(4-tert-butylcyclohexyl) peroxydicarbonate.

[0102] Preferably, the free radical initiator is selected from 2,2'-azobis(2-methylbutyronitrile), 2,2-bis(tert-butylperoxy)butane, tert-butyl peroxy-2-ethylhexanoate, 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane, tert-butyl peroxybenzoate, and tert-butyl peroxy-3,5,5-trimethylhexanoate. Particularly preferred initiators are tert-butyl peroxy-2-ethylhexanoate and 2,2-bis(tert-butylperoxy)butane.

[0103] Preferably, the total amount of the free radical initiator is 0.01 to 5% by weight, more preferably 0.02 to 1% by weight, and most preferably 0.05 to 0.5% by weight, relative to the total weight of the monomer composition of polymer (V) or polymer (P).

[0104] The total amount of the free radical initiator can be added in a single step, or it can be added in multiple steps during the polymerization reaction. Preferably, the free radical initiator is added in multiple steps. For example, a portion of the free radical initiator can be added to initiate free radical polymerization, and a second portion of the free radical initiator can be added 0.5 to 3.5 hours after the initial metering.

[0105] Preferably, step (y) further includes adding a chain transfer agent. Suitable chain transfer agents are, in particular, oil-soluble thiols, such as n-dodecyl mercaptan or 2-mercaptoethanol, or chain transfer agents selected from terpenes, such as terpinene. The addition of n-dodecyl mercaptan is particularly preferred.

[0106] Preferably, the total reaction time of the free radical polymerization is 2 to 10 hours, more preferably 3 to 9 hours.

[0107] After the free radical polymerization is completed, the obtained polymers (P) and (V) are mixed to provide the additive composition (A) according to the invention. The additive composition (A) is then preferably further diluted to the desired viscosity with the aforementioned oil. Preferably, the additive composition (A) contains at least 25% by weight of solid polymer based on the total weight of the polymers (P) and (V) in the additive composition (A).

[0108] Use of the additive composition according to the present invention

[0109] The present invention also relates to the use of the additive composition as a lubricant additive in lubricating oil formulations for improving the storage stability, viscosity index and low-temperature performance of the lubricating oil formulations.

[0110] The present invention also relates to a method for improving the storage stability, viscosity index and low-temperature performance of a lubricating oil formulation by incorporating the additive composition (A) according to the present invention as a lubricant additive into the lubricating oil formulation.

[0111] Therefore, the additive composition (A) of the present invention can be used as a lubricant additive in lubricant formulations, resulting not only in improved compatibility and storage stability, but also in improved low-temperature performance and improved viscosity index. This approach thus avoids any incompatibility between different additive package components, dispersants, and other additives in the lubricant formulations, because the additive composition of the present invention combines two additive lubricant polymers, namely VII and PPD, which exhibit very good compatibility and viscosity measurement properties.

[0112] Lubricating oil formulations comprising the additive compositions according to the present invention

[0113] This invention also relates to lubricating oil formulations, which contain...

[0114] (i) a base oil or a mixture of base oils; and

[0115] (ii) The additive composition (A) according to the present invention.

[0116] The lubricating oil formulation may optionally contain additional additives as described below (iii).

[0117] The concentration (also referred to as treatment rate) of the additive composition (A) according to the invention in the lubricating oil formulation can vary over a wide range, for example, from 0.1 to 99.5% by weight, or from 0.5 to 99.5% by weight. Preferably, the amount of the one or more base oils (component i) is 0.5 to 80% by weight, more preferably 50 to 80% by weight, and the amount of the additive composition (component ii) is preferably 20 to 99.5% by weight, more preferably 20 to 50% by weight, respectively, based on the total weight of the lubricating oil formulation.

[0118] Preferably, the total amount of (i) and (ii) is 95 to 100% by weight.

[0119] The additive composition (A) of the present invention and lubricating oil formulations comprising the additive composition according to the present invention are advantageously used in drive system lubricants (e.g., manual transmission fluids, differential gear oils, automatic transmission fluids and belt continuously variable transmission fluids, axial fluid formulations, dual-clutch transmission fluids and special hybrid transmission fluids), hydraulic oils (e.g., hydraulic oils for mechanical devices, power steering fluids, shock absorber oils), engine oils (for gasoline engines and for diesel engines) and industrial oil formulations (e.g., wind turbines).

[0120] If the lubricating oil formulation according to the invention is used as an engine oil, it preferably contains 0.5% to 10% by weight, more preferably 0.5% to 8% by weight, of the additive composition according to the invention based on the total weight of the lubricating oil composition, resulting in a 4mm... 2 / s to 10mm 2 Kinematic viscosity at 100°C within the range of / s.

[0121] If the lubricating oil formulation of the present invention is used as an automotive gear oil, it preferably contains 0.5% to 10% by weight, more preferably 0.5% to 8% by weight, of the additive composition according to the present invention based on the total weight of the lubricating oil composition, resulting in a 2mm... 2 / s to 15mm 2 Kinematic viscosity at 100°C within the range of / s.

[0122] If the lubricant composition of the present invention is used as an automatic transmission oil, it preferably contains 0.5% to 10% by weight, more preferably 0.5% to 8% by weight, of the additive composition according to the present invention based on the total weight of the lubricant composition, resulting in a 2mm... 2 / s to 6mm 2 Kinematic viscosity at 100°C within the range of / s.

[0123] The kinematic viscosity can be measured according to ASTM D445. Preferably, the kinematic viscosity is measured at temperatures of 100°C and 40°C.

[0124] The base oil (i) used in the lubricating oil formulation preferably contains an oil with a lubricating viscosity. Such oils include natural and synthetic oils, oils derived from hydrocracking, hydrogenation and hydrotreatment, unrefined, refined, refined oils or mixtures thereof.

[0125] The base oil may also be defined as specified by the American Petroleum Institute (API) (see the April 2008 edition of Appendix E - API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils, Section 1.3, Subheading 1.3, "Base Stock Categories").

[0126] The API currently defines five groups of lubricant base materials (API 1509, Annex E—API Base Oil Interchangeability Guide for Bus and Diesel Engine Oils, September 2011). Groups I, II, and III are mineral oils, classified by the amount of saturates and sulfur they contain and by their viscosity index; Group IV is polyalphaolefins; and Group V is all other substances, including, for example, ester oils. Table 1 below illustrates these API classifications.

[0127] surface 1:

[0128]

[0129] The kinematic viscosity (KV) at 100°C of a suitable base oil for preparing the lubricant composition according to the invention 100 According to ASTM D445, it is preferred to be within 1mm. 2 / s to 10mm 2 Within the range of / s, more preferably within 1mm 2 / s to 8mm 2 Within the range of / s, or even more preferably within 1mm 2 / s to 5mm 2 Within the range of / s.

[0130] Another base oil available according to the invention is a Fischer-Tropsch-derived base oil from Groups II to III.

[0131] Fischer-Tropsch derived base oils are known in the art. The term "Fischer-Tropsch derived" means that the base oil is or is derived from a synthetic product of the Fischer-Tropsch process. Fischer-Tropsch derived base oils may also be referred to as GTL (Gastrointestinal Flour) base oils. Suitable Fischer-Tropsch derived base oils that can be conveniently used as base oils in the lubricating compositions of the present invention are, for example, those disclosed in the following documents: EP0776959, EP0668342, WO97 / 21788, WO00 / 15736, WO00 / 14188, WO00 / 14187, WO00 / 14183, WO00 / 14179, WO00 / 08115, WO99 / 41332, EP1029029, WO01 / 18156, WO01 / 57166, and WO2013 / 189951.

[0132] Especially for transmission fluid formulations, a mixture of API Group III base oils and different Group III oils is used. In a preferred embodiment, the one or more base oils (i) are one API Group III base oil, or a mixture of multiple API Group III base oils.

[0133] The lubricating oil formulations according to the invention are further characterized by their low kinematic viscosity at temperatures of 40°C or lower. The KV 40 Preferably below 40mm 2 / s, more preferably 20 to 40 mm 2 / s. The KV 40 It is the kinematic viscosity at 40°C and can be measured according to ASTM D445.

[0134] The lubricating oil formulation preferably has a viscosity index greater than 180, more preferably greater than 200, and most preferably greater than 210. The viscosity index can be measured according to ASTM D2270.

[0135] The lubricating oil formulation according to the present invention is preferably a transmission fluid or lubricating engine oil formulation.

[0136] The lubricating oil formulation according to the present invention may also contain additional additives as component (iii), which are selected from friction modifiers, dispersants, defoamers, detergents, antioxidants, anti-wear additives, extreme pressure additives, anti-corrosion additives, dyes and mixtures thereof.

[0137] Suitable dispersants include poly(isobutylene) derivatives, such as poly(isobutylene)succinimide (PIBSI), including borated PIBSI; and ethylene-propylene oligomers with N / O functional groups.

[0138] The dispersant (including borate dispersants) is preferably used in an amount of 0 to 5% by weight based on the total amount of the lubricant composition.

[0139] Suitable defoamers are silicone oil, fluorosilicone oil, and fluoroalkyl ether.

[0140] The defoamer is preferably used in an amount of 0.005 to 0.1% by weight based on the total amount of the lubricant composition.

[0141] Preferred detergents include metal-containing compounds such as phenolates; salicylates; thiophosphonates, especially thiopyrophosphonates, thiophosphonates, and phosphonates; sulfonates, and carbonates. These compounds may contain, in particular, calcium, magnesium, and barium as metals. These compounds are preferably used in neutral or highly alkaline forms.

[0142] The detergent is preferably used in an amount of 0.2 to 1% by weight based on the total amount of the lubricant composition.

[0143] Suitable antioxidants include, for example, phenol-based antioxidants and amine-based antioxidants.

[0144] Phenolic-based antioxidants include, for example, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; 4,4'-methylenebis(2,6-di-tert-butylphenol); 4,4'-bis(2,6-di-tert-butylphenol); 4,4'-bis(2-methyl-6-tert-butylphenol); 2,2'-methylenebis(4-ethyl-6-tert-butylphenol); 2,2'-methylenebis(4-methyl-6-tert-butylphenol); 2,6-tert-butylphenol); 4,4'-butylidenebis(3-methyl-6-tert-butylphenol); 4,4'-isopropylidenebis(2,6-di-tert-butylphenol); 2,2'-methylenebis(4-methyl-6-nonylphenol); 2,2'-isobutylidenebis(4,6-dimethylphenol); 2,2'-methylenebis(4-methyl-6-cyclohexylphenol); 2,6-di-tert-butyl-4-methylphenol Phenol; 2,6-di-tert-butyl-4-ethylphenol; 2,4-dimethyl-6-tert-butylphenol; 2,6-di-tert-pentyl-p-cresol; 2,6-di-tert-butyl-4-(N,N'-dimethylaminomethylphenol); 4,4'-thiobis(2-methyl-6-tert-butylphenol); 4,4'-thiobis(3-methyl-6-tert-butylphenol); 2,2'-thiobis(4-methyl-6-tert-butylphenol) Bisphenol-based antioxidants; bis(3-methyl-4-hydroxy-5-tert-butylbenzyl) sulfide; bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide; n-octyl 3-(4-hydroxy-3,5-di-tert-butylphenyl)propionate; n-octadecyl 3-(4-hydroxy-3,5-di-tert-butylphenyl)propionate; 2,2'-thio[diethyl-bis-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. Particularly preferred are bisphenol-based antioxidants and phenol-based antioxidants containing ester groups.

[0145] The amine-based antioxidants include, for example, monoalkyl diphenylamines, such as monooctyl diphenylamine and monononyl diphenylamine; dialkyl diphenylamines, such as 4,4'-dibutyl diphenylamine, 4,4'-dipentyl diphenylamine, 4,4'-dihexyl diphenylamine, 4,4'-diheptyl diphenylamine, 4,4'-dioctyl diphenylamine, and 4,4'-dinonyl diphenylamine; polyalkyl diphenylamines, such as tetrabutyl diphenylamine, tetrahexyl diphenylamine, tetraoctyl diphenylamine, and tetranonyl diphenylamine; naphthylamines, specifically, α-naphthylamine, phenyl-α-naphthylamine, and other alkyl-substituted phenyl-α-naphthylamines, such as butylphenyl-α-naphthylamine, pentylphenyl-α-naphthylamine, hexylphenyl-α-naphthylamine, heptylphenyl-α-naphthylamine, octylphenyl-α-naphthylamine, and nonylphenyl-α-naphthylamine. In terms of their antioxidant effects, diphenylamine is superior to naphthylamine.

[0146] Suitable antioxidants can be further selected from sulfur and phosphorus-containing compounds, such as metal dithiophosphates, such as zinc dithiophosphate (ZnDTP), “OOS triester” = the reaction product of dithiophosphate with activated double bonds from alkenes, cyclopentadiene, norbornene, α-pinene, polybutene, acrylates, and maleates (ashless upon combustion); organosulfur compounds, such as dialkyl sulfides, diaryl sulfides, polysulfides, modified thiols, thiophene derivatives, xanthates, thioglycols, thioaldehydes, and sulfur-containing carboxylic acids; heterocyclic sulfur / nitrogen compounds, especially dialkyldimercaptothiadiazole and 2-mercaptobenzimidazole; bis(dialkyldithiocarbamate)zinc and methylene bis(dialkyldithiocarbamate); organophosphorus compounds, such as triaryl phosphites and trialkyl esters; organocopper compounds and highly basic calcium- and magnesium-based phenolates and salicylates.

[0147] The antioxidant is used in an amount of 0 to 15% by weight, preferably 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, based on the total amount of the lubricant composition.

[0148] Preferred anti-wear and extreme pressure additives include sulfur-containing compounds, such as zinc dithiophosphate, diC 3-12 Alkyl dithiophosphate zinc (ZnDTP), zinc phosphate, zinc dithiocarbamate, molybdenum dithiocarbamate, molybdenum dithiophosphate, disulfides, sulfurized olefins, sulfurized oils and fats, sulfurized esters, thiocarbonates (salts), thiocarbamates (salts), polysulfides; phosphorus-containing compounds, such as phosphites (salts), phosphate esters (salts), such as trialkyl phosphates, triaryl phosphates, such as tricresyl phosphate, amine-neutralized mono- and dialkyl phosphates, ethoxylated mono- and dialkyl phosphates, phosphonates, phosphine, amine salts or metal salts of these compounds; sulfur- and phosphorus-containing antiwear agents, such as thiophosphites (salts), thiophosphates (salts), thiophosphonates (salts), amine salts or metal salts of these compounds.

[0149] The anti-wear agent may be present in an amount of 0 to 3% by weight, preferably 0.1 to 1.5% by weight, and more preferably 0.5 to 0.9% by weight, based on the total amount of the lubricant composition.

[0150] Preferred friction modifiers may include mechanically active compounds such as molybdenum disulfide, graphite (including fluorinated graphite), poly(trifluoroethylene), polyamide, and polyimide; compounds that form an adsorption layer, such as long-chain carboxylic acids, fatty acid esters, ethers, alcohols, amines, amides, and imides; compounds that form a layer through tribochemical reactions, such as saturated fatty acids, phosphoric acid and thiophosphate esters, xanthogenates, and sulfurized fatty acids; compounds that form a polymeric layer, such as ethoxylated dicarboxylate esters, dialkyl phthalates, methacrylates, unsaturated fatty acids, sulfurized olefins, and organometallic compounds, such as molybdenum compounds (molybdenum dithiophosphate and molybdenum dithiocarbamate MoDTC) and their combinations with ZnDTP, and copper-containing organic compounds.

[0151] Some of the compounds listed above can fulfill multiple functions. For example, ZnDTP is primarily an anti-wear additive and extreme pressure additive, but it also exhibits characteristics of an antioxidant and corrosion inhibitor (here: metal passivator / deactivator).

[0152] The additives detailed above are described in particular in T. Mang, W. Dresel (eds.): "Lubricants and Lubrication", Wiley-VCH, Weinheim 2001; and R.Mortier, S.T. Orszulik (eds.): "Chemistry and Technology of Lubricants".

[0153] Preferably, the total concentration of the one or more additives (iii) is up to 20% by weight based on the total weight of the lubricating oil formulation, more preferably from 0.05% to 15% by weight, and even more preferably from 5% to 15% by weight.

[0154] Preferably, based on the total weight of the lubricating oil formulation, the total amount of (i) to (iii) is 90 to 100% by weight, more preferably 95 to 100% by weight, and even more preferably 100% by weight. Detailed Implementation

[0155] Experimental Section

[0156] The present invention will be further illustrated in detail below with reference to embodiments and comparative embodiments, but is not intended to limit the scope of the invention.

[0157] abbreviation

[0158] C1 AMA (C1-alkyl methacrylate) = Methyl methacrylate (MMA)

[0159] C4 AMA C4-alkyl methacrylate = n-butyl methacrylate

[0160] C 12 / 14 AMA (Methacrylic Acid) - C 12 / 14 -alkyl esters

[0161] C 16 / 18 AMA (Methacrylic Acid) - C 16 / 18 -alkyl esters

[0162] CTA chain transfer agent

[0163] DDM dodecyl mercaptan

[0164] f 支化 branching degree

[0165] Initiator: tert-butyl peroxy-2-ethylhexanoate

[0166] KV 40 Kinematic viscosity at 40°C as measured according to ASTM D7042

[0167] KV 100 Kinematic viscosity at 100°C as measured according to ASTM D7042

[0168] MA-1 is a macromolecular alcohol (M) of hydrogenated polybutadiene with methacrylate functional groups. n =2,000 g / mol)

[0169] MA-2 is a macromolecular alcohol (M) of hydrogenated polybutadiene with methacrylate functional groups. n =4,750 g / mol)

[0170] MM-1 is a macromonomer of hydrogenated polybutadiene with methacrylate functional groups (M n =2,000 g / mol)

[0171] MM-2 is a macromonomer of hydrogenated polybutadiene with methacrylate functional groups (M n =4,750 g / mol)

[0172] M n Number average molecular weight

[0173] M w weight average molecular weight

[0174] NB3020 3020, Group III base oil, derived from Neste, with a KV of 2.2 cSt. 100

[0175] NB3043 3043, Group III base oil, derived from Neste, with a KV of 4.3 cSt. 100

[0176] Base oil (C) is a commercially available blend of API base oils Yubase 3 (API Group II base oil) and Yubase 4plus (API Group III base oil) in a 70 / 30 weight ratio, obtained from SK Lubricants Co., Ltd., with KV values ​​of 3.1 and 4.2 cSt respectively. 100 .

[0177] OEM Original Equipment Manufacturer

[0178] The PDI (Polydispersive Index) is determined by M... w / M n Calculated molecular weight distribution

[0179] Styrene

[0180] VI. Viscosity index measured according to ASTM D2270

[0181] Test methods

[0182] The polymers according to the present invention and comparative embodiments were characterized in terms of their molecular weight and PDI.

[0183] In this invention, the weight-average molecular weight (M) of the polymer (pour point depressant (P) and viscosity index improver (V)) is... w The result was determined by gel permeation chromatography (GPC) using polymethyl methacrylate (PMMA) calibration standards under the following measurement conditions:

[0184] Eluent: Tetrahydrofuran (THF)

[0185] Operating temperature: 40℃

[0186] Column assembly: This column assembly consists of one pre-column (PSS-SDV) 10μm 8.0×50mm) and three columns (2×PSS-SDV Linear XL 10μm 8.0×300mm, 1×PSS-SDV) Composed of 10μm (8.0×300mm), all columns have an average particle size of 10μm (PSS Standards Service GmbH, Mainz, Germany).

[0187] Flow rate: 1 mL / min

[0188] Injection volume: 100μL

[0189] Instrument: Shodex GPC101, which consists of an autosampler, pump, and column oven.

[0190] Detection device: a refractive index detector obtained from Shodex.

[0191] The number-average molecular weight (M) of the macromonomer n The determination was performed by gel permeation chromatography (GPC) using polybutadiene calibration standards (PSS Standards Service GmbH, Mainz, Germany) according to DIN 55672-1 under the following measurement conditions:

[0192] Eluent: Tetrahydrofuran (THF)

[0193] Operating temperature: 35℃

[0194] Column assembly: This column assembly consists of one pre-column (PSS-SDV; 10μm; 8×50mm), four PSS-SDV columns (SDV-LXL, SDV-LinL) with dimensions of 300×8mm and an average particle size of 10μm, and two SDV columns. (PSSSstandards Service GmbH, Mainz, Germany) and a solvent peak separation column with a size of 8×100 mm (KF-800D from Shodex).

[0195] Flow rate: 1 mL / min

[0196] Injection volume: 100μL

[0197] Instrument: Agilent 1100 series, consisting of an autosampler, pump, and column oven.

[0198] Detection device: Refractive index detector from the Agilent 1100 series.

[0199] Additive compositions (A) comprising polymers (P) and (V) according to the present invention and comparative embodiments are compared with their viscosity index (VI) according to ASTM D 2270 and their kinematic viscosity (kV) at 40°C according to ASTM D7042. 40 ) and kinematic viscosity at 100°C (KV) 100 ) is characterized.

[0200] After the additive composition (prepared by blending (V) and (P)) is prepared, a 1-week storage test is conducted at 25°C, and the results are determined by visual observation. "Good" means the additive composition exhibits a clear appearance after storage. "Poor" means the additive composition exhibits a cloudy appearance, indicating heterogeneity and a risk of separation during long-term storage. Generally, the additive composition is stored in drums or bulk containers. If the additive composition separates into two phases (VII and PPD) during storage, the fluid containing the additive composition will not provide suitable viscosity properties because an appropriate dose of VII and PPD has not been added to the fluid due to the separation.

[0201] Synthesis of macromolecular alcohols (hydroxylated hydrogenated polybutadiene) MA-1 and MA-2

[0202] The macromolecular alcohol was synthesized by anionic polymerization of 1,3-butadiene and butyllithium at 20-45°C. Upon reaching the desired degree of polymerization, the reaction was terminated by adding propylene oxide, and lithium was removed by precipitation with methanol. Subsequently, the polymer was hydrogenated under a hydrogen atmosphere in the presence of a noble metal catalyst at up to 140°C and 200 bar pressure. After hydrogenation, the noble metal catalyst was removed, and the organic solvent was extracted under reduced pressure. Finally, MA-2 was diluted with NB3020 to a polymer content of 70% by weight. MA-1 was maintained at 100%.

[0203] Table 2 summarizes the characterization data for MA-1 and MA-2.

[0204] Table 2: Characterization data of the macromolecular monomers used.

[0205] <![CDATA[M n [g / mol]]]> Hydrogenation level [%) OH functionality [%) MA-1 2,000 >99 >98 MA-2 4,750 >99 >98

[0206] Synthesis of macromonomers MM-1 and MM-2

[0207] In a 2L stirred apparatus equipped with a saber-type stirrer, air inlet, thermocouple with controller, heating jacket, column with random packing of 3mm wire spirals, vapor distributor, top thermometer, reflux condenser, and substrate cooler, 1000g of the aforementioned macromolecular alcohol was dissolved in methyl methacrylate (MMA) at 60°C by stirring. 20 ppm of 2,2,6,6-tetramethylpiperidin-1-oxy radical and 200 ppm of hydroquinone monomethyl ether were added to the solution. After heating to reflux (bottom temperature approximately 110°C) while passing air through for stabilization, approximately 20 mL of MMA was distilled off for azeotropic drying. After cooling to 95°C, LiOCH3 was added, and the mixture was heated back to reflux. After approximately 1 hour of reaction time, the top temperature had dropped to approximately 64°C due to methanol formation. The formed methanol / MMA azeotrope was continuously distilled off until a constant top temperature of approximately 100°C was re-established. The mixture was allowed to react at this temperature for another hour. For further post-processing, most of the MMA was extracted under reduced pressure. Insoluble catalyst residues were removed by pressure filtration (Seitz T1000 depth filter).

[0208] Table 3 summarizes the amounts of macroalcohol, MMA, and LiOCH3 used in the synthesis of macromonomers MM-1 and MM-2.

[0209] Table 3 The amount of macromolecular alcohol, MMA, and catalyst used for the transesterification of the macromolecular monomer.

[0210]

[0211] Due to their high molecular weight, the hydroxylated hydrogenated polybutadiene may also be referred to as a macromolecular alcohol in the context of this invention. In the context of this invention, the corresponding (meth)acrylic acid ester may also be referred to as a macromolecular monomer (monomer a)).

[0212] Synthesis of polymers according to the present invention

[0213] Working Example: Viscosity Index Improver (V-1)The monomer mixture with the composition shown in Table 5 was diluted with a 1.3 / 98.7 mixture of Nexbase3020 and Hydroroseal G232 H to achieve a monomer concentration of 60 wt% in the oil. 50 wt% of the reaction mixture prepared above was initially charged into a apparatus equipped with a four-necked flask and a precision glass saber stirrer. After heating to 90°C under nitrogen, 0.18 wt% (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane initiator was added to the reaction mixture to initiate the reaction. The same amount of initiator and Hydroroseal G232 H were added to another 50% of the reaction mixture to achieve a monomer concentration of 40 wt% in the oil, and this was added to the flask at a constant temperature of 90°C for three hours. The reaction was maintained at 90°C, and 0.2 wt% (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane was added 1 hour after the metered addition of the reaction mixture. The reaction mixture was stirred at 90°C for another 2 hours, and 0.2% (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane was added, and then diluted with Hydroroseal G232 H to a 35% by weight solution of the polymer in oil to obtain the final VII (V-1).

[0214] Working Example: Viscosity Index Improver (V-2)

[0215] The monomer mixture with the composition shown in Table 5 was diluted with a 15.52 / 65.45 / 19.03 mixture of Nexbase 3020, Hydroroseal G232 H, and Nexbase 3043 to achieve a monomer concentration of 60% by weight in the oil. 50% by weight of the reaction mixture prepared above was initially charged into a apparatus equipped with a four-necked flask and a precision glass saber stirrer. After heating to 90°C under nitrogen, 0.09% by weight (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane initiator was added to the reaction mixture to initiate the reaction. 0.29% (relative to the amount of monomer) of the initiator was added to the remaining 50% of the reaction mixture, and this was continuously added to the flask at 90°C for three hours. The reaction was maintained at 90°C, and 0.18 wt% (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane and Nexbase 3043 were added to the flask over a constant period of three hours after metered addition of the reaction mixture, such that the product solids at the end of the feeding were 39.8 wt%. The reaction mixture was stirred at 90°C for another 2 hours, and 0.18 wt% (relative to the amount of monomer) of 2,2-bis(tert-butylperoxy)butane was added, followed by dilution with Nexbase 3043 to a 25 wt% solution of the polymer in oil to give the final VII (V-2).

[0216] Pour point lowering agents P-1 to P-6 in the working examples and Pour point lowering agents P-7* and P-8* in the comparative examples

[0217] An initial charge of a monomer mixture consisting of monomers and DDM, and Hydroroseal G232H, as shown in Table 4, was added to a four-necked round-bottom glass flask equipped with a condenser, stirrer, and thermocouple, such that the monomer concentration in the oil was 97.7% by weight. The monomer mixture was then heated to 120°C under nitrogen.

[0218] Preparation of the initiator solution: 0.2 wt% (relative to the total weight of the monomer) of 2,2-bis(tert-butylperoxy)butane initiator was diluted with Hydroroseal G232 H to make the concentration of the initiator in the oil 20 wt%.

[0219] Add 10% by weight of the total initiator solution to the flask over 45 minutes. Then add 20% by weight of the total initiator feed mixture to the flask over 45 minutes. After that, raise the reaction temperature to 105°C and add the remaining initiator feed mixture to the flask over 30 minutes. Maintain the reaction mixture at 105°C for 60 minutes, then add Hydroroseal G232H to make the product solids 56.66% by weight, and stir at 105°C for 60 minutes to obtain the final PPD (working examples: P-1 to P-6 and comparative examples: P-7* and P-8*).

[0220] Table 4 below shows the reaction mixtures used for the preparation work and comparative examples. The monomer components total 100%. The amount of chain transfer agent is given relative to the total amount of monomer. Weight-average molecular weight (M) w (This is also shown in Table 4.)

[0221] The above-mentioned PPDs (P-1 to P-6, P-7* and P-8*) and VII (V-1 and V-2) were mixed to obtain additive compositions (working examples: Examples A-1 to A-10 and comparative examples: Comparative Examples A-1* to Comparative Examples A-3*). The blending ratios, polymer content and appearance (storage test) are shown in Tables 5 and 6 below.

[0222] The working examples of the additive compositions (Examples A-1 to A-10) showed a clear appearance after storage testing, which means that the combination of VII and PPD according to the invention results in an additive composition with good compatibility and good storage performance. In contrast, the comparative additive compositions (Comparative Examples A-1* to Comparative Examples A-3*) showed a cloudy appearance due to the poor compatibility between component VII and component PPD.

[0223]

[0224] Table 6 Comparative additive compositions: blending ratios, appearance, and solids content of the additive compositions (Comparative Examples A-1* to Comparative Examples A-3) * )

[0225]

[0226] *) Comparative Examples

[0227] Evaluation of candidate additive compositions

[0228] The additive compositions A-1 to A-4 and A-6 according to the present invention, and the comparative additive compositions A-1* to A-3*, were formulated together with ATF packets and base oil (C) according to the blending ratios shown in Table 7, and the KV was evaluated. 100 KV 40 VI and BF-40. The lubricating oil formulations of the present invention, Example F and comparative lubricating oil formulations, Comparative Example F, and their viscosity properties are shown in Table 7 below.

[0229] To verify the improvement in viscosity index when the additive composition of the present invention is used in lubricating oil formulations, the KV of all fluids was measured. 100 Adjust to 4.9-5.0 cSt.

[0230] The lubricating oil formulations of Examples F-1 to F-3 and Comparative Example F-1* all comprise the same VII component V-1. While maintaining adequate low-temperature performance (BF-40), the formulations according to the invention (Examples F-1 to F-3) also exhibit a much higher viscosity index compared to the comparative formulation Comparative Example F-1*, with a difference of 3 to 7 points in the VI value.

[0231] The lubricating oil formulations of the present invention, Examples F-4 to F-5, and the comparative lubricating oil formulations, Comparative Examples F-2* and F-3*, all comprise the same VII component V-2. While maintaining suitable low-temperature performance (BF-40), the formulations according to the present invention (Examples F-4 to F-5) also exhibit a much higher viscosity index compared to the comparative formulations, Comparative Examples F-2* and F-3*, with a difference of 6 to 8 points in the VI value.

[0232]

Claims

1. An additive composition (A) comprising a viscosity index improver (V) and a pour point reducer (P). wherein the viscosity index improver (V) is a polymer having a weight average molecular weight (M w ) of 100,000 to 1,000,000 g / mol, and is obtained by polymerizing a monomer composition comprising: a) 10 to 30% by weight of one or more polybutadiene-based macromonomers having a number average molecular weight of 500 to 10,000 g / mol, based on the total weight of the monomer composition. b) 50 to 70% by weight of methyl methacrylate, butyl methacrylate, a monomer having 8 to 17 carbon atoms selected from styrene or substituted styrene having alkyl substituents in the side chain, or a mixture thereof, based on the total weight of the monomer composition. c) 1 to 15% by weight of (meth)acrylic acid linear or branched C7-C based on the total weight of the monomer composition. 30 A monomer of an alkyl ester, or a mixture thereof, The pour point depressant (P) described herein has a weight-average molecular weight (M) of 10,000 to 60,000 g / mol. w The polymer is obtained by polymerizing a monomer composition comprising the following substances: e) 20 to 35% by weight, based on the total weight of the monomer composition, of a monomer selected from linear or branched C1-C6 alkyl esters of (meth)acrylic acid, or a mixture thereof, of which the monomer composition may contain a monomer selected from linear or branched C1-C6 alkyl esters of (meth)acrylic acid. f) 20 to 75% by weight of (meth)acrylic acid linear or branched C7-C based on the total weight of the monomer composition. 15 A monomer of alkyl esters, g) Based on the total weight of the monomer composition, 5 to 60% by weight of at least one linear or branched C-type (meth)acrylic acid. 16 -C 24 Monomers of alkyl esters The weight ratio of viscosity index improver (V) to pour point reducer (P) in the additive composition is from 99:1 to 80:20, based on the total solid polymer content of the viscosity index improver (V) and pour point reducer (P).

2. The additive composition (A) according to claim 1, wherein the viscosity index improver (V) has a weight-average molecular weight of 100,000 to 600,000 g / mol.

3. The additive composition (A) according to claim 1 or 2, wherein the polybutadiene-based macromonomer a) has a number-average molecular weight of 1,000 to 6,000 g / mol.

4. The additive composition (A) according to claim 3, wherein the polybutadiene-based macromonomer a) has a number-average molecular weight of 1,500 to 5,500 g / mol.

5. The additive composition (A) according to claim 1 or 2, wherein the monomer (e) is selected from methyl methacrylate, butyl methacrylate, or a mixture thereof.

6. The additive composition (A) according to claim 1 or 2, wherein the amount of monomer f) is 20 to 60 by weight based on the total weight of the monomer composition of the pour point lowering agent (P).

7. The additive composition (A) according to claim 6, wherein the amount of monomer f) is 25 to 55% by weight based on the total weight of the monomer composition of the pour point lowering agent (P).

8. The additive composition (A) according to claim 1 or 2, wherein the amount of monomer (g) is 20 to 50 by weight based on the total weight of the monomer composition of the pour point depressant (P).

9. The additive composition (A) according to claim 8, wherein the amount of monomer (g) is 25 to 50% by weight based on the total weight of the monomer composition of the pour point lowering agent (P).

10. The additive composition (A) according to claim 1 or 2, wherein the total amount of monomers e), f) and g) in the monomer composition of the pour point depressant (P) is 95 to 100 by weight based on the total weight of the monomer composition of the pour point depressant (P).

11. The additive composition (A) according to claim 1 or 2, wherein the amount of monomer (b) is 55 to 70% by weight based on the total weight of the monomer composition of the viscosity index improver (V).

12. The additive composition (A) according to claim 1 or 2, wherein the monomer c) is selected from linear C-methacrylic acid. 12-14 Alkyl esters, linear C-chain methacrylic acid 16-18 Alkyl esters or mixtures thereof.

13. The additive composition (A) according to claim 1 or 2, wherein the monomer composition of the viscosity index improver (V) further comprises 0 to 20% by weight of monomer (d), which is selected from (meth)acrylates of ether alcohols, aminoalkyl (meth)acrylates, aminoalkyl (meth)acrylamides, or mixtures thereof.

14. The additive composition (A) of claim 13, wherein the monomer composition of the viscosity index improver (V) further comprises 0.1 to 20% by weight of said monomer d.

15. The additive composition (A) of claim 13, wherein the monomer composition of the viscosity index improver (V) further comprises 0.1 to 15% by weight of said monomer d.

16. The additive composition (A) of claim 13, wherein the monomer composition of the viscosity index improver (V) further comprises 0.1 to 10% by weight of said monomer d.

17. The additive composition (A) according to claim 13, wherein the total amount of monomers a), b), c) and d) in the monomer composition of the viscosity index improver (V) is 95 to 100 by weight based on the total weight of the monomer composition.

18. A method for preparing an additive composition (A) as defined in any one of claims 1 to 17, wherein the method comprises the following steps: (x) A viscosity index improver (V) is prepared by providing a monomer composition and initiating free radical polymerization in the monomer composition. (y) A pour point lowering agent (P) is prepared by providing a monomer composition and initiating free radical polymerization in the monomer composition. (z) The viscosity index improver (V) is mixed with the pour point reducer (P) to provide the additive composition (A).

19. Lubricating oil formulations, comprising: (i) a base oil or a mixture of base oils; and (ii) The additive composition (A) as defined in any one of claims 1 to 17.

20. Use of the additive composition (A) as defined in any one of claims 1 to 17 as a lubricant additive in a lubricating oil formulation for improving the storage stability, viscosity index and low-temperature performance of said lubricating oil formulation.

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