WO2021027209A1 - Composition containing star-shaped binary ethylene-propylene copolymer for improving lubricating oil viscosity index and preparation method thereof - Google Patents

Abstract

Disclosed is a composition containing star-shaped binary ethylene-propylene copolymer for improving lubricating oil viscosity index and a preparation method thereof. The composition is mainly a solid of a star-shaped polymer prepared by melt polymerization of a binary copolymer (I), a catalyst (II), a modified monomer (III), and an auxiliary monomer (IV), or a liquid composition of the star-shaped polymer prepared by solution polymerization. The invention can improve the shear stability or low-temperature performance of OCP-type VII oil products without reducing detergency thereof.

Description

Composition containing star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition and preparation method thereof Technical field

The invention belongs to the technical field of lubricating oil modification, and in particular relates to a lubricating oil viscosity index improver composition and a preparation method thereof.

Background technique

Viscosity index improver (VII) is an oil-soluble polymer compound that is rubbery or solid at room temperature. It is usually diluted with a 150SN or 100SN neutral oil to a 5-10% concentrate for use (Li Zhongming. A kind of Viscosity index improver of lubricating oil composition. CN 108048167A). Adding VII to the lubricating oil can obtain a multi-grade oil with good low-temperature startability, suitable high-temperature viscosity, universal use in all seasons and long service life. The polymer chain of VII in the lubricating oil is fully extended at high temperature to increase viscosity; at low temperature, it will shrink and curl, which has little effect on viscosity. Therefore, compared with the single-grade lubricating oil with the same viscosity, the multi-grade oil containing VII has a higher viscosity index and a smooth viscosity-temperature curve.

The viscosity index improver of ethylene-propylene copolymer (OCP) has better viscosity, shear stability and viscosity-temperature performance, and the raw materials are easily available and the process is simple (Xiang Wencheng. Dispersed ethylene-propylene copolymer viscosity index improver. Lubrication) Oil. 1994,5:36-42.), often used in the formulation of internal combustion engine oil. The disadvantage is that OCP viscosity index improvers have poor low temperature performance. Studies have shown that the low temperature performance of OCP viscosity index improvers is related to the structure and molecular weight size and distribution of the molecular chain. The larger the molecular weight, the more significant the molecular chain entanglement at low temperature, and the greater the flow resistance under a certain shear rate. The narrower the molecular weight distribution, the smaller the ratio of long-chain and short-chain molecules, the smaller the possibility of chain scission under a certain shearing force, and the stronger the viscosity retention. In addition, the greater the molar ratio of the propyl sequence in the molecular chain of the ethylene-propylene copolymer, the greater the number of methyl substituents, the stronger the molecular chain entanglement, the greater the shear resistance, and the poor low-temperature startability. (Wang Guojin, Zhu Heju, Ye Yuankai, Chen Yuezhu. The influence of molecular structure of OCP viscosity index improver on low temperature performance. Lubrication and Sealing. 1999, 6: 26-29.)

At present, engine equipment is developing in the direction of high speed, small size, high power, environmental protection and energy saving, and the requirements for the viscosity increasing performance, shear stability, oxidation detergency, and low temperature resistance of the OCP class VII used are becoming more stringent. The shear stability index of the existing OCP is less than 55 (30 cycles SSI for diesel nozzles, the smaller is the better the shear stability), and the low temperature apparent viscosity index CCSI is less than 200 (measured at -20℃, the smaller the lower the temperature The better the performance), the high temperature oxidation detergency is below 4.0 (heat pipe oxidation rating, the smaller the oil detergency). In order to meet the demand, it is necessary to modify the ethylene-propylene copolymer. The commonly used method is to graft OCP with polar monomers or prepare polar monomer copolymers (Chen Dehong, Song Qingwu, Liu Jianxin. Dispersed antioxidant type ethylene propylene copolymer Development of the viscosity index improver DAOCP. Petroleum Refining and Chemical Industry. 2001, 1:34-36.), although the performance has been improved to a certain extent, there are still viscosity increasing performance, shear stability, oil detergency, and low temperature resistance Performance and other issues that cannot be balanced.

For example, the patent application 201610522192.1 discloses a method for polymer-modified lubricating oil. The method includes: directly mixing the polymer solution obtained after the polymerization reaction with the lubricating oil base oil, wherein the polymer is selected from ethylene propylene rubber , At least one of hydrogenated styrene-butadiene block polymer and hydrogenated styrene-isoprene block polymer. The method provided by the present invention can overcome the existing technology of solid lubricating oil viscosity index modifiers that cannot improve the fluidity of the modified lubricating oil obtained at ultra-low temperature when the lubricant base oil is modified. Provides higher viscosity increase at high temperature, which affects the defect of viscosity-temperature characteristics of lubricating oil. However, the polymer cannot improve the shear stability under low temperature conditions, and has problems such as viscosity increasing performance, shear stability, oil detergency, and low temperature resistance.

Summary of the invention

Based on this, the primary purpose of the present invention is to provide a viscosity index improver for lubricating oils containing star-shaped binary ethylene-propylene copolymers that improves the shear stability or low temperature performance without reducing the detergency of OCP VII oils. The composition and its preparation method.

The object of the present invention is to provide a viscosity index improver composition containing a star-shaped binary ethylene-propylene copolymer lubricating oil that takes into account viscosity increasing (thickening ability), shear stability, oil detergency and low temperature performance, and preparation thereof The method reduces the occurrence of irreversible crosslinking, and improves the production efficiency and reliability of the product.

In order to achieve the above objective, the technical solution of the present invention is:

A composition containing a star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver is characterized in that the composition is mainly composed of a binary copolymer (I), a catalyst (II), and a modified monomer (III). ), the auxiliary monomer (IV) is a paste or block of a star polymer prepared by a melt polymerization method, or a star polymer composition prepared by a solution polymerization method.

The solid is a paste or a block.

Among them, in terms of parts by mass, the binary copolymer (I) is not less than 96 parts, the catalyst (II) is not more than 0.3 parts, the modified monomer (III) is not more than 3.2 parts, and the auxiliary monomer (IV) ) Does not exceed 0.5 copies.

Further, the binary copolymer (I) is a linear copolymer composed of the unit (α) and the unit (β) with minimal crystallinity, and its number average molecular weight is 20,000 to 500,000. The unit (α) and the unit The formula for (β) is

Furthermore, the binary copolymer can typically be selected from any one or any combination of ethylene-propylene block copolymers, ethylene-propylene random copolymers, and hydrogenated polyisoprene.

The catalyst (II) is an organic compound containing a structural unit of formula (γ). Wherein, R1 and R2 are hydrogen atoms and any one or any combination of C1-12 alkyl, cycloalkyl, aryl, keto, carbonate, ester, and acyl groups; wherein, the alkyl group , Cycloalkyl, aryl, ester, carbonate, keto, and acyl groups can be further substituted with 1 to 6 substituents independently selected from alkyl, cycloalkyl, and aryl groups. The formula (γ) is as follows:

Further, the catalyst (II) can typically be selected from hydrogen peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, di-tert-butyl peroxide, diphenyl peroxide Any one of formyl, lauryl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy-t-valerate, diisopropyl peroxydicarbonate, and dicyclohexyl peroxydicarbonate.

The modified monomer (III) is a compound containing more than two (δ) or (ε) groups, and the molecular formula of (δ) or (ε) is as follows:

Further, the modified monomer (III) can typically be selected from trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol Triacrylate, 3 (propoxy) glycerol triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, di (trimethylolpropane) tetraacrylate, pentaerythritol tetraacrylate, Any one or any combination of 4 (ethoxy) pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate.

The auxiliary monomer (IV) is any one of styrene, acrylamide, and thiuram derivatives containing the structure of formula (φ), wherein R3 and R4 can be C1-7 alkyl or cycloalkyl Any one or any combination of, aryl, benzyl, isobutyl, piperidinyl, wherein the structure of formula (φ) is as follows:

Further, the thiuram derivative can typically be selected from tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabenzylthiuram disulfide, Dimethyldiphenylthiuram disulfide, diisobutylthiuram disulfide, dicyclopentamethylene disulfide tetraalkylthiuram, dipentamethylenethiuram tetrasulfide, hexasulfide Double Five A support Qiulam and so on.

A melt polymerization method containing a star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition, characterized in that the method includes the following steps:

(11) Accurately weigh the catalyst (II) and dissolve it in the solvent to obtain the solution (A); spray the solution (A) evenly into the binary copolymer pellets (B), stir, and let stand until the solvent is completely After volatilization, the mixture (C) is obtained;

(12) Extrude the mixed modified material (C) through the extruder, control the extrusion temperature to be between 120-300℃, and add the modified monomer (III) dropwise to the middle or end of the heating section of the extruder The composition (D) mixed with the auxiliary monomer (IV) is extruded to obtain the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition.

In the melt polymerization method, the solvent used is a solvent that can dissolve the catalyst but cannot dissolve the binary copolymer (I), and can be acetone, ethyl acetate, methanol, ethanol, and other solvents that are easy to volatilize.

A solution polymerization method containing a star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition, characterized in that the method comprises the following steps:

(21) Add the binary copolymer (I) in batches to the reactor containing the base oil, control the temperature not to exceed 130°C, start the stirrer to dissolve the copolymer, and the mass ratio of the copolymer in the base oil is not More than 30%.

(22) Raise the temperature to 130℃～300℃, and then inject the catalyst (II) into the reactor. After 1～30min reaction, the binary copolymer will be degraded to form macromolecular free radicals;

(23) Reinject the modified monomer (III) and auxiliary monomer (IV), continue stirring for 10-30 minutes, and cool the material to obtain the star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver combination Things.

The base oil is a mineral base oil, a synthetic base oil, or a vegetable base oil. The base oil has a kinematic viscosity at 40°C of 5.0-160.0 mm ² /s, or a kinematic viscosity at 100°C of 1.5-34.0 mm ² /s.

The main components of the mineral base oil include alkanes, cycloalkanes, aromatic hydrocarbons, cycloalkyl aromatic hydrocarbons and organic compounds containing oxygen, nitrogen, and sulfur; synthetic oils can be polyalphaolefins, synthetic esters, polyethers, silicone oils, fluorine-containing oils, and phosphoric acid Any one or any combination of esters; vegetable base oils are natural animal and vegetable oils containing ester bonds in the molecular structure.

In the present invention, by adding the catalyst (II), the structural unit (β) on the binary copolymer is degraded, and the proportion of the (β) unit on the molecular chain is reduced; at the same time, since the degradation is random, the molecular weight distribution of the obtained molecular chain will be Very wide. Further control the order and amount of addition of catalyst (II) and modified monomer (III), so that macromolecular free radicals can react with modified monomer (III) to form long-chain branched star copolymers and improve thickening Ability; the use of auxiliary monomer (IV) reduces the occurrence of irreversible crosslinking.

Furthermore, the star-shaped polymer formed by the present invention shrinks the molecular chain at low temperature, but does not cause serious entanglement, and has little effect on viscosity; at high temperature, the molecular chain stretches, which has a significant effect on lubricating oil viscosity. The amount of lubricating oil can be reduced, and the main carbon chain and (β) units are reduced, which helps to improve the shear stability.

More importantly, the proportion of structural units (β) is reduced and the molecular weight distribution of the molecular chain is broadened, and the low temperature performance of the obtained VII is remarkable. The preparation method of the modified copolymer overcomes the crosslinking problem in the polymerization reaction process, and greatly improves the thickening ability, shear stability, low temperature performance, and high temperature oxidation detergency of lubricating oil VII prepared by the modified copolymer .

detailed description

In order to make the objectives, technical solutions, and advantages of the present invention clearer and more comprehensible, the following further describes the present invention in detail in conjunction with embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention.

The viscosity index improver composition of the lubricating oil containing star-shaped binary ethylene-propylene copolymer realized by the present invention is mainly composed of binary copolymer (I), catalyst (II), modified monomer (III), auxiliary monomer (IV) Star-shaped polymer paste or block prepared by melt polymerization method, or star-shaped polymer composition prepared by solution polymerization method. In the composition and preparation process, it is not ruled out that other auxiliary preparations can be added.

Among them, in terms of parts by mass, the binary copolymer (I) is not less than 96 parts, the catalyst (II) is not more than 0.3 parts, the modified monomer (III) is not more than 3.2 parts, and the auxiliary monomer (IV) ) Does not exceed 0.5 copies.

Specifically, the binary copolymer (I) is a linear copolymer composed of the unit (α) and the unit (β) with minimal crystallinity, and its number average molecular weight is 20,000 to 500,000, and the unit (α) And the formula of unit (β) is

Furthermore, the binary copolymer can typically be selected from any one of ethylene-propylene block copolymers, ethylene-propylene random copolymers, hydrogenated polyisoprene, and hydrogenated styrene-butadiene copolymers. Kind or any combination.

The catalyst (II) is an organic compound containing a structural unit of formula (γ). Wherein, R1 and R2 are hydrogen atoms and any one or any combination of C1-12 alkyl, cycloalkyl, aryl, keto, carbonate, ester, and acyl groups; wherein, the alkyl group , Cycloalkyl, aryl, ester, carbonate, keto, and acyl groups can be further substituted with 1 to 6 substituents independently selected from alkyl, cycloalkyl, and aryl groups. The formula (γ) is as follows:

In specific implementation, the catalyst (II) can typically be selected from hydrogen peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, di-tert-butyl peroxide, peroxide Any of dibenzoyl, lauryl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy-t-valerate, diisopropyl peroxydicarbonate, and dicyclohexyl peroxydicarbonate .

The modified monomer (III) is a compound containing more than two (δ) or (ε) groups, and the molecular formula of (δ) or (ε) is as follows:

The modified monomer (III) can typically be selected from trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate Esters, 3 (propoxy) glycerol triacrylate, tris (2-hydroxyethyl) isocyanuric acid triacrylate, di (trimethylolpropane) tetraacrylate, pentaerythritol tetraacrylate, 4 ( Ethoxy) any one or any combination of pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate.

The auxiliary monomer (IV) is any one of styrene, acrylamide, and thiuram derivatives containing the structure of formula (φ), wherein R3 and R4 can be C1-7 alkyl or cycloalkyl Any one or any combination of, aryl, benzyl, isobutyl, piperidinyl, wherein the structure of formula (φ) is as follows:

The thiuram derivative can typically be selected from tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabenzylthiuram disulfide, disulfide Dimethyldiphenylthiuram, diisobutylthiuram disulfide, dicyclopentamethylene disulfide tetraalkylthiuram, bispentamethylenethiuram tetrasulfide, hexasulfide A support Qiuram and so on.

The melt polymerization method containing the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition realized by the present invention includes the following steps:

(11) Accurately weigh the catalyst (II) and dissolve it in the solvent to obtain the solution (A); spray the solution (A) evenly into the binary copolymer pellets (B), stir, and let stand until the solvent is completely After volatilization, the mixture (C) is obtained;

(12) Extrude the mixed modified material (C) through the extruder, control the extrusion temperature to be between 120-300℃, and add the modified monomer (III) dropwise to the middle or end of the heating section of the extruder The composition (D) mixed with the auxiliary monomer (IV) is extruded to obtain the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition.

In the melt polymerization method, the solvent used is a solvent that can dissolve the catalyst but cannot dissolve the binary copolymer (I), and can be acetone, ethyl acetate, methanol, ethanol, and other solvents that are easy to volatilize.

The solution polymerization method containing the star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition realized by the present invention is characterized in that the method includes the following steps:

(21) Add the binary copolymer (I) in batches to the reactor containing the base oil, control the temperature not to exceed 130°C, start the stirrer to dissolve the copolymer, and the mass ratio of the copolymer in the base oil is not More than 30%.

(22) Raise the temperature to 130℃～300℃, and then inject the catalyst (II) into the reactor. After 1～30min reaction, the binary copolymer will be degraded to form macromolecular free radicals;

(23) Reinject the modified monomer (III) and auxiliary monomer (IV), continue stirring for 10-30 minutes, and cool the material to obtain the star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver combination Things.

The base oil is a mineral base oil, a synthetic base oil, or a vegetable base oil. The base oil has a kinematic viscosity at 40°C of 5.0-160.0 mm ² /s, or a kinematic viscosity at 100°C of 1.5-34.0 mm ² /s.

The main components of the mineral base oil include alkanes, cycloalkanes, aromatic hydrocarbons, cycloalkyl aromatic hydrocarbons and organic compounds containing oxygen, nitrogen, and sulfur; synthetic oils can be polyalphaolefins, synthetic esters, polyethers, silicone oils, fluorine-containing oils, and phosphoric acid Any one or any combination of esters; vegetable base oils are natural animal and vegetable oils containing ester bonds in the molecular structure.

The specific implementation is as follows:

Example one:

Melt polymerization method:

Accurately weigh the hydroperoxide catalyst (II) (select one of hydrogen peroxide, cumene hydroperoxide, and tert-butyl hydroperoxide), and dissolve it in a solvent to obtain a solution (A). Spray the solution (A) evenly into the binary copolymer (ethylene-propylene block copolymer) pellets (B) and stir, and let it stand for a period of time until the solvent is completely volatilized to obtain the mixture (C); change the mixture to The material (C) is extruded on the extruder, and the extruding temperature is controlled to 150℃. The modified monomer (III) trimethylolpropane triacrylate and auxiliary monomer are added dropwise in the middle or end of the heating section of the extruder. The mixture (D) formed by body (IV) styrene is extruded to obtain a star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition.

In terms of dosage, the standard is: in terms of parts by mass, 97.3 parts of the binary copolymer (I), 0.2 parts of the catalyst (II), 2.0 parts of the modified monomer (III), and 0.5 parts of the auxiliary monomer (IV). Copies.

The lubricating oil viscosity index improver composition formed in this embodiment was dissolved in a base oil with a kinematic viscosity of 5.1 mm ² /s at 100°C at a concentration of 10%. The test (ie 10% concentration liquid glue, the same below) was tested at 100°C. Viscosity is 1401mm ² /s, shear stability index SSI 24 (diesel nozzle SSI), thickening capacity 6.0mm ² /s; low temperature apparent viscosity index CCSI up to 80 (tested at -20℃), high temperature oxidation detergency Up to 3.5 level (heat pipe oxidation).

Solution polymerization method:

Add the binary copolymer (I) ethylene-propylene block copolymer into the reactor containing the base oil (IV) in batches, control the temperature not to exceed 130°C, start the stirrer, and dissolve the binary copolymer. The mass fraction of meta-copolymer in the base oil should not exceed 30%. Among them, the base oil is mineral oil. The main components of the mineral base oil include alkanes, cycloalkanes, aromatics, cycloalkyl aromatics, and organic compounds containing oxygen, nitrogen, and sulfur. The base oil may have a kinematic viscosity of 5.0-160.0 mm ² /s at 40°C and/or a kinematic viscosity of 1.50-34.0 mm ² /s at 100°C. After the temperature is raised to 165°C and the reaction temperature is stabilized, the hydroperoxide catalyst (II) (hydrogen peroxide, cumene hydroperoxide, tert-butyl hydroperoxide) is injected into the reactor, and the reaction is carried out for 30 minutes. Make the binary copolymer degrade to form macromolecular free radicals; then inject the modified monomer (III) trimethylolpropane triacrylate and the auxiliary monomer (IV) styrene into the reactor, and continue to stir for 10 minutes to make The macromolecular free radicals initiate the reaction of the multifunctional modified monomers to form a lubricant viscosity index improver composition concentrate with a star-shaped structure, and the liquid concentrate with a certain concentration is obtained by cooling down and discharging the material.

In terms of dosage, the standard is: in terms of parts by mass, 97.3 parts of the binary copolymer (I), 0.2 parts of the catalyst (II), 2.0 parts of the modified monomer (III), and 0.5 parts of the auxiliary monomer (IV). Copies. The lubricating oil viscosity index improver composition concentrate (10% liquid gum) formed in this example has a kinematic viscosity of 1245 mm ² /s at 100°C, a shear stability index of 19 (30 cycles of diesel nozzle SSI), and a thickening capacity of 6.3 mm ² /s, low temperature apparent viscosity index CCSI can reach 55 (measured at -20℃), high temperature oxidation detergency 3.5 (heat pipe oxidation).

Embodiment two:

Example 2 Based on Example 1, the modified monomer was replaced with trimethylolpropane trimethacrylate, and the remaining operation steps and dosage requirements were as in Example 1.

The lubricating oil viscosity index improver composition (melt polymerization product) formed in this example has a kinematic viscosity at 100°C of 1255 mm ² /s and a shear stability index of 14 (30 cycles SSI for diesel nozzles). Thickening capacity 6.2mm ² /s, low temperature apparent viscosity index CCSI up to 58 (measured at -20°C), high temperature oxidation detergency up to 3.5 (heat pipe oxidation); the viscosity index of the lubricating oil formed in the embodiment is improved Agent composition concentrate (solution polymerization product, 10% liquid glue) 100℃ kinematic viscosity is 1263mm ² /s, shear stability index 16 (diesel nozzle 30 cycle SSI), thickening capacity 6.2mm ² /s, low temperature table The visual viscosity index CCSI can reach 72 (measured at -20°C), and the high temperature oxidation detergency is 3.5 (heat pipe oxidation).

In other embodiments, the modifying monomer can be trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, 3 (propoxy) propylene triacrylate, Alcohol triacrylate, tris(2-hydroxyethyl) isocyanuric acid triacrylate, di(trimethylolpropane) tetraacrylate, pentaerythritol tetraacrylate, 4(ethoxy) pentaerythritol tetraacrylate, double Any one or more of pentaerythritol hexaacrylate.

Example three:

Example 3 Based on Example 1, the auxiliary monomer was replaced with acrylamide. For the remaining operation steps and dosage requirements, refer to Example 1.

The 100°C kinematic viscosity of the 10% concentration liquid glue of the lubricating oil viscosity index improver composition (melt polymerization product) formed in this example is 1212 mm ² /s, and the shear stability index is 15 (30 cycles of diesel nozzle SSI), Thickening capacity 5.7mm ² /s, low temperature apparent viscosity index CCSI up to 67 (measured at -20°C), high temperature oxidation detergency 3.5 (heat pipe oxidation); the lubricant viscosity index improver formed in the embodiment The composition concentrate (solution polymerization product, 10% liquid glue) 100℃ kinematic viscosity is 1243mm ² /s, shear stability index 15 (diesel nozzle 30 cycle SSI), thickening capacity 5.4mm ² /s, low temperature appearance The viscosity index CCSI can reach 69 (measured at -20℃), and the high temperature oxidation detergency can reach 3.5 grades (heat pipe oxidation).

In other embodiments, the auxiliary monomer may be any one of styrene, acrylamide, and a thiuram derivative containing a structure of formula (φ).

Embodiment four:

Melt polymerization method:

Accurately weigh one of the dialkyl peroxide catalysts (II) (such as dicumyl peroxide, di-tert-butyl peroxide) and dissolve it in the solvent to obtain the solution (A). Spray the solution (A) evenly into the binary copolymer (ethylene-propylene random copolymer) pellets (B) and stir, and let it stand for a period of time until the solvent is completely volatilized to obtain the mixture (C); change the mixture to The material (C) is extruded on the extruder, and the extrusion temperature is controlled to 300°C. The modified monomer (III) trimethylolpropane triacrylate and auxiliary monomers are added dropwise to the middle or end of the heating section of the extruder. Body (VI) acrylamide is extruded to obtain the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition.

In terms of dosage, the standard is: in terms of parts by mass, 96.4 parts of the binary copolymer (I), 0.3 parts of the catalyst (II), 3.0 parts of the modified monomer (III), and 0.3 parts of the auxiliary monomer (IV) Copies.

The concentrated liquid of the lubricating oil viscosity index improver composition (10% liquid gum) formed in this example has a kinematic viscosity of 960 mm ² /s at 100°C, a shear stability index of 10 (30 cycles SSI for diesel nozzles), and thickening ability 4.9mm ² /s, low temperature apparent viscosity index CCSI 84 (measured at -20℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

Solution polymerization method:

Add the binary copolymer (I) ethylene-propylene random copolymer into the reactor containing the base oil in batches, control the temperature not to exceed 130°C, and start the stirrer to dissolve the binary copolymer. The mass ratio in the base oil does not exceed 30%. The base oil is a synthetic base oil, and the synthetic oil can be any one or more of polyalphaolefin, synthetic ester, polyether, silicone oil, fluorine-containing oil, and phosphate ester. The base oil may have a kinematic viscosity of 5.0-160.0 mm ² /s at 40°C and/or a kinematic viscosity of 1.50-34.0 mm ² /s at 100°C. After the temperature is raised to 300°C and the reaction temperature is stabilized, the catalyst (II) dialkyl peroxide (such as dicumyl peroxide, di-tert-butyl peroxide) is injected into the reactor, and the reaction is carried out for 20 minutes to make the two The copolymer is degraded to form macromolecular free radicals; then the modified monomer (III) trimethylolpropane triacrylate and the auxiliary monomer (IV) styrene are injected into the reactor, and the stirring is continued for 30 minutes to make the macromolecule Free radicals initiate the reaction of multifunctional modified monomers to form a lubricant viscosity index improver composition concentrate with a star-shaped structure, and the liquid concentrate with a certain concentration can be obtained by cooling down and discharging.

In terms of dosage, the standard is: in terms of parts by mass, 96.4 parts of the binary copolymer (I), 0.3 parts of the catalyst (II), 3.0 parts of the modified monomer (III), and 0.3 parts of the auxiliary monomer (IV) Copies.

The lubricating oil viscosity index improver composition concentrate (10% liquid gum) formed in this embodiment has a kinematic viscosity of 1245 mm ² /s at 100°C, a shear stability index of 9 (30 cycles of diesel nozzle SSI), and a thickening capacity of 4.8 mm ² /s, low temperature apparent viscosity index CCSI can reach 85 (measured at -20℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

Embodiment five:

Example 5 Based on Example 4, the modified monomer was replaced with trimethylolpropane trimethacrylate. Refer to Example 4 for the remaining operation steps and dosage standards.

The 10% concentrate 130-kinematic viscosity of the lubricating oil viscosity index improver composition formed in this example is 1212 mm ² /s, the shear stability index is 12 (30 cycles of diesel nozzle SSI), and the thickening capacity is 4.8 mm ² / s, low temperature apparent viscosity index CCSI can reach 87 (measured at -20℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

The lubricating oil viscosity index improver composition concentrate (solution polymerization product, 10% liquid glue) formed in the embodiment has a kinematic viscosity of 920 mm ² /s at 100°C and a shear stability index of 12 (30 cycles SSI for diesel nozzles) , Thickening capacity 5.8mm ² /s, low temperature apparent viscosity index CCSI up to (measured at -20 ℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

In other embodiments, the modifying monomer can be trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, 3 (propoxy) propylene triacrylate, Alcohol triacrylate, tris(2-hydroxyethyl) isocyanuric acid triacrylate, di(trimethylolpropane) tetraacrylate, pentaerythritol tetraacrylate, 4(ethoxy) pentaerythritol tetraacrylate, double Any one or more of pentaerythritol hexaacrylate.

Embodiment 6:

Example 6 Based on Example 4, the auxiliary monomer was replaced with acrylamide. For the remaining operation steps and dosage standards, refer to Example 4.

The lubricating oil viscosity index improver composition formed in this example (the kinematic viscosity of the molten polymer product at 100°C is 1221 mm ² /s, the shear stability index is 15 (the diesel nozzle is 30 cycles SSI), and the thickening capacity is 6.1 mm ² /s, the low-temperature apparent viscosity index CCSI can reach 75 (measured at -20°C), and the high-temperature oxidation detergency level 3 (heat pipe oxidation). The lubricant viscosity index improver composition concentrate (solution Polymerized product, 10% liquid glue) 100℃ kinematic viscosity is 1156mm ² /s, shear stability index 14 (30 cycles SSI for diesel nozzle), thickening capacity 5.8mm ² /s, low temperature apparent viscosity index CCSI up to 88 (Measured at -20℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

In other embodiments, the auxiliary monomer may be any one of styrene, acrylamide, and a thiuram derivative containing a structure of formula (φ).

Embodiment Seven:

Melt polymerization method:

Accurately weigh the peroxyester catalyst (II) (one of tert-butyl peroxybenzoate and tert-butyl peroxyvalerate) and dissolve it in a solvent to obtain a solution (A). Spray the solution (A) evenly into the binary copolymer mixture pellets (B) and stir, and let it stand for a period of time until the solvent is completely volatilized to obtain the mixture (C); the mixed modified material (C) is extruded Extrude on the machine, control the extrusion temperature to 250°C, add the modified monomer (IV) trimethylolpropane triacrylate and auxiliary monomer acrylamide dropwise in the middle or end of the heating section of the extruder, after extrusion That is, the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition is obtained.

In terms of dosage, the standard is: according to mass parts, the said binary copolymer (I) 97.5 parts, catalyst (II) 0.2 parts, modified monomer (III) 2.0 parts, auxiliary monomer (IV) 0.3 Copies. The lubricating oil viscosity index improver composition formed in this example has a 10% liquid gum 100°C kinematic viscosity of 1031 mm ² /s, a shear stability index of 16 (30 cycles of diesel nozzle SSI), and a thickening capacity of 5.0 mm ² / s, low temperature apparent viscosity index CCSI can reach 76 (measured at -20℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

Solution polymerization method:

Add the binary copolymer (I) hydrogenated polyisoprene in batches to the reactor containing the base oil (IV), control the temperature not to exceed 130°C, and start the stirrer to dissolve the binary copolymer. The mass ratio of the copolymer in the base oil does not exceed 30%. Among them, the base oil is a vegetable base oil, which is a natural animal and vegetable oil with an ester bond in the molecular structure. The base oil may have a kinematic viscosity of 28.0-160.0 mm ² /s at 40°C and/or a kinematic viscosity of 1.50-34.0 mm ² /s at 100°C. After raising the temperature to 212°C and making the reaction temperature stable, inject the catalyst (II) peroxyesters (tert-butyl peroxybenzoate, tert-butyl peroxyvalerate) into the reactor, and react for 30/10min (When tert-butyl peroxybenzoate is used as the initiator, the reaction time is 30 minutes; when tert-butyl peroxide is used as the initiator, the reaction time is 10 minutes), the binary copolymer is degraded to form macromolecular free radicals; Inject the modified monomer (IV) trimethylolpropane triacrylate and the auxiliary monomer containing the thiuram derivative of the formula (φ) structure into the reactor, and continue to stir for 20 minutes to cause the macromolecular free radicals to initiate polyfunctionality The modified monomer reacts to form a lubricant oil viscosity index improver composition concentrate with a star-shaped structure, and the liquid concentrate with a certain concentration is obtained by cooling and discharging.

In terms of dosage, the standard is: in terms of parts by mass, 96 parts of the binary copolymer (I), 0.3 parts of the catalyst (II), 3.2 parts of the modified monomer (III), and 0.5 parts of the auxiliary monomer (IV) Copies.

The lubricating oil viscosity index improver composition concentrate (10% liquid gum) formed in this example has a kinematic viscosity of 1123 mm ² /s at 100°C, a shear stability index of 16 (30 cycles of diesel nozzle SSI), and a thickening capacity of 5.2 mm ² /s, low temperature apparent viscosity index CCSI can reach 81 (measured at -20℃), high temperature oxidation detergency 3.5 (heat pipe oxidation).

Embodiment 8:

Example 8 Based on Example 7, the modified monomer was replaced with trimethylolpropane trimethacrylate. For the remaining operation steps and dosage standards, refer to Example 7.

The lubricating oil viscosity index improver composition (melt polymerization product) formed in this example has a kinematic viscosity of 1134 mm ² /s at 100°C, a shear stability index of 13 (30 cycles SSI for diesel nozzles), and a thickening capacity of 5.6 mm ² / s, low temperature apparent viscosity index CCSI82 (measured at -20°C), high temperature oxidation detergency level 3 (heat pipe oxidation).

The lubricating oil viscosity index improver composition concentrate (solution polymerization product, 10% liquid glue) formed in the embodiment has a kinematic viscosity at 100°C of 1411 mm ² /s, and a shear stability index of 14 (30 cycles for diesel nozzles) SSI), thickening capacity 6.7mm ² /s, low temperature apparent viscosity index CCSI up to 50 (measured at -20 ℃), high temperature oxidation detergency level 3 (heat pipe oxidation).

In other embodiments, the modifying monomer can be trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, 3 (propoxy) propylene triacrylate, Alcohol triacrylate, tris(2-hydroxyethyl) isocyanuric acid triacrylate, di(trimethylolpropane) tetraacrylate, pentaerythritol tetraacrylate, 4(ethoxy) pentaerythritol tetraacrylate, double Any one or more of pentaerythritol hexaacrylate.

Example 9:

Example 9 Based on Example 7, the auxiliary monomer was replaced with acrylamide. For the remaining operation steps and dosage standards, refer to Example 7.

The lubricating oil viscosity index improver composition (melt polymerization product) formed in this example has a kinematic viscosity of 1282 mm ² /s at 100°C, a shear stability index of 18 (30 cycles of diesel nozzle SSI), and a thickening capacity of 5.9 mm ² / s, low temperature apparent viscosity index CCSI 69 (measured at -20°C), high temperature oxidation detergency 3.5 (heat pipe oxidation). The lubricating oil viscosity index improver composition concentrate (solution polymerization product, 10% liquid glue) formed in the embodiment has a kinematic viscosity of 887 mm ² /s at 100°C and a shear stability index of 13 (30 cycles SSI for diesel nozzles) , Thickening capacity 4.7mm ² /s, low temperature apparent viscosity index CCSI 71 (measured at -20°C), high temperature oxidation detergency level 3 (heat pipe oxidation).

Therefore, the above-mentioned examples prove that the present invention, by adding the catalyst (II), degrades the upper structural unit (β) of the binary copolymer, and reduces the proportion of the (β) unit on the molecular chain; at the same time, because the degradation is random Yes, the molecular weight distribution of the resulting molecular chain will be very broad. Further control the order and amount of addition of catalyst (II) and modified monomer (III), so that macromolecular free radicals can react with modified monomer (III) to form long-chain branched star copolymers and improve thickening Ability; the use of auxiliary monomer (IV) reduces the occurrence of irreversible crosslinking.

The star-shaped polymer formed by the present invention shrinks the molecular chain at low temperature, but does not cause serious entanglement, and has little influence on viscosity; at high temperature, the molecular chain stretches, which has a significant effect on lubricating oil and reduces the dosage. In addition, the main carbon chain and (β) units are reduced, which helps to improve the shear stability. More importantly, the proportion of structural units (β) is reduced and the molecular weight distribution of the molecular chain is broadened, and the low temperature performance of the obtained VII is remarkable. The preparation method of the modified copolymer overcomes the crosslinking problem in the polymerization reaction process, and greatly improves the thickening ability, shear stability, low temperature performance, and high temperature oxidation detergency of lubricating oil VII prepared by the modified copolymer .

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement and improvement made within the spirit and principle of the present invention shall be included in the protection of the present invention. Within range.

Claims (10)

1. A composition containing a star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition, which is characterized in that the composition is mainly composed of a binary copolymer (I), a catalyst (II), and a modified monomer ( III) A solid star polymer prepared by the auxiliary monomer (IV) through a melt polymerization method, or a liquid composition of a star polymer prepared by a solution polymerization method.
2. The lubricating oil viscosity index improver composition containing a star-shaped binary ethylene-propylene copolymer as claimed in claim 1, characterized in that the binary copolymer (I) is not less than 96 parts by mass. Catalyst (II) does not exceed 0.3 parts, modified monomer (III) does not exceed 3.2 parts, and auxiliary monomer (IV) does not exceed 0.5 parts.
3. The viscosity index improver composition of a lubricating oil containing a star-shaped binary ethylene-propylene copolymer as claimed in claim 1, wherein the binary copolymer (I) is composed of a unit (α) and a unit (β) The linear copolymer with minimized crystallinity has a number average molecular weight of 20,000 to 500,000. The formula of unit (α) and unit (β) is

   
4. The viscosity index improver composition of a lubricating oil containing a star-shaped binary ethylene-propylene copolymer as claimed in claim 1, wherein the catalyst (II) is an organic compound containing a structural unit of formula (γ), wherein R1 And R2 are hydrogen atoms and any one or any combination of C1-12 alkyl, cycloalkyl, aryl, keto, carbonate, ester, and acyl groups; the formula (γ) is as follows:

   
5. The viscosity index improver composition of a lubricating oil containing a star-shaped binary ethylene-propylene copolymer according to claim 1, wherein the modified monomer (III) contains two or more (δ) or (ε) The compound of the group, the molecular formula of (δ) or (ε) is as follows:

   
6. The viscosity index improver composition of a lubricating oil containing a star-shaped binary ethylene-propylene copolymer as claimed in claim 1, wherein the auxiliary monomer (IV) is styrene, acrylamide, and structure containing formula (φ) Any one of the thiuram derivatives, wherein R3 and R4 are any one or any combination of C1-7 alkyl, cycloalkyl, aryl, benzyl, isobutyl, piperidinyl, Among them, the structure of formula (φ) is as follows:

   
7. A melt polymerization method containing a star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition, characterized in that the method includes the following steps:

   Accurately weigh the catalyst (II) and dissolve it in the solvent to obtain the solution (A); spray the solution (A) evenly into the binary copolymer pellets (B), stir, and let stand until the solvent is completely volatilized. Obtain the mixture (C);

   Extrude the mixed modified material (C) through the extruder, control the extrusion temperature to be between 120-300°C, and add the modified monomer (III) and auxiliary monomers to the middle or end of the heating section of the extruder. The composition (D) formed by mixing the body (IV) is extruded to obtain the star-shaped binary ethylene-propylene copolymer lubricating oil viscosity index improver composition.
8. The melt polymerization method containing the star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition according to claim 7, wherein the solvent used in the melt polymerization method is capable of dissolving the catalyst but not The solvent of the binary copolymer (I) is any one of acetone, ethyl acetate, methanol, and ethanol.
9. A solution polymerization method containing a star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition, characterized in that the method comprises the following steps:

   (1) Add the binary copolymer (I) in batches to the reactor containing the base oil, control the temperature not to exceed 130°C, start the stirrer to dissolve the copolymer, and the mass ratio of the copolymer in the base oil is not More than 30%.

   (2) Raise the temperature to 130℃～300℃, and then inject the catalyst (II) into the reaction kettle. After 1～30min reaction, the binary copolymer will be degraded to form macromolecular free radicals;

   (3) Reinject modified monomer (III) and auxiliary monomer (IV), continue to stir for 10-30 minutes, and cool the material to obtain the star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver combination Things.
10. The solution polymerization method containing a star-shaped binary ethylene-propylene copolymer lubricant viscosity index improver composition according to claim 9, wherein the base oil is a mineral base oil, a synthetic base oil, or a vegetable base oil, The 40°C kinematic viscosity of the base oil is 5.0-160.0mm ² /s, or the 100°C kinematic viscosity is 1.5-34.0mm ² /s; the main components of the mineral base oil include alkanes, naphthenes, aromatics, cycloalkyl aromatics and Organic compounds containing oxygen, nitrogen, and sulfur; synthetic oil is any one or any combination of poly-α olefin, synthetic ester, polyether, silicone oil, fluorine-containing oil, and phosphate ester; vegetable base oil contains ester bonds in the molecular structure Natural animal and vegetable oils.