Hyperbranched temperature-resistant and salt-resistant lubricant, preparation method and application thereof

Abstract

This invention relates to the field of polymer materials technology, and particularly to a hyperbranched high-temperature and salt-resistant lubricant, its preparation method, and its application. The hyperbranched high-temperature and salt-resistant lubricant comprises methyl acrylate-modified amine compounds and sodium allyl sulfonate-modified polyetheramines. The methyl acrylate-modified amine compounds contain ester groups, and the sodium allyl sulfonate-modified polyetheramines contain amino groups. The ester groups and amino groups form amide bonds through an amino-ester exchange reaction, connecting the methyl acrylate-modified amine compounds and the sodium allyl sulfonate-modified polyetheramines. The resulting hyperbranched high-temperature and salt-resistant lubricant exhibits excellent lubrication performance, high-temperature resistance, and salt resistance.

Description

Technical Field

[0001] This application relates to the field of polymer materials technology, and in particular to a hyperbranched, temperature-resistant, and salt-resistant lubricant, its preparation method, and its application. Background Technology

[0002] Currently, drilling fluid lubricants, both domestically and internationally, are classified into liquid and solid lubricants based on their phase state. Compared to solid lubricants, such as graphite, plastic microspheres, and glass microspheres, liquid lubricants are the most researched and widely used due to their advantages, including less impact on drilling fluid flowability, better compatibility with drilling fluids, less susceptibility to removal by solid control equipment during use, less residue in the soil after use, and environmental friendliness.

[0003] However, commonly used liquid lubricants, such as mineral oils, vegetable oils, alcohol ethers, and polyalphaolefins, all suffer from insufficient lubrication and drag reduction properties, poor temperature and salt resistance, and difficulty in long-term use in high-temperature and high-salt environments.

[0004] Therefore, developing a new type of liquid lubricant with good lubrication performance, high temperature resistance, and high salt resistance has extremely important application value. Summary of the Invention

[0005] This invention provides a hyperbranched, high-temperature resistant, and salt-resistant lubricant, its preparation method, and its application, which exhibits excellent lubrication performance, high-temperature resistance, and salt resistance.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, this application provides a method for preparing a hyperbranched, high-temperature, and salt-resistant lubricant, comprising the following steps:

[0008] Methyl acrylate and polyethylene polyamine compounds are mixed and reacted to obtain methyl acrylate-modified amine compounds;

[0009] Sodium allyl sulfonate and polyetheramine are mixed and reacted to obtain sodium allyl sulfonate-modified polyetheramine;

[0010] Methyl acrylate-modified amine compounds and sodium allyl sulfonate-modified polyetheramines were mixed and reacted to obtain a hyperbranched, temperature-resistant, and salt-resistant lubricant.

[0011] Optionally, in some embodiments of this application, the mixture of methyl acrylate and polyethylene polyamine compounds includes:

[0012] A first dispersion and methyl acrylate, wherein the first dispersion includes a polyethylene polyamine compound and a first solvent;

[0013] Methyl acrylate was added dropwise to the first dispersion.

[0014] Optionally, in some embodiments of this application, the first solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, trimethoxymethanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide; and / or

[0015] Polyethylene polyamine compounds are selected from one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0016] Optionally, in some embodiments of this application, the molar concentration of the polyethylene polyamine compound in the first dispersion is 0.1 mol / L to 1 mol / L; and / or

[0017] The molar ratio of polyethylene polyamine compounds to methyl acrylate is 1:(4~20); and / or

[0018] The reaction temperature of methyl acrylate and polyethylene polyamine compounds is 25℃~45℃, and the reaction time is 18h~48h.

[0019] Optionally, in some embodiments of this application, the mixture of sodium allyl sulfonate and polyetheramine comprises:

[0020] The second dispersion and sodium allyl sulfonate, wherein the second dispersion includes polyetheramine and a second solvent;

[0021] Sodium allyl sulfonate was added dropwise to the second dispersion.

[0022] Optionally, in some embodiments of this application, the polyetheramine contains at least two amino groups.

[0023] Optionally, in some embodiments of this application, polyetheramine is... Where n is an integer from 1 to 5; and / or

[0024] The second solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, trimethoxymethanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide; and / or

[0025] In the second dispersion, the molar concentration of polyetheramine is 1 mol / L to 10 mol / L; and / or

[0026] The molar ratio of polyetheramine to sodium allyl sulfonate is 1:(0.9~1); and / or

[0027] The reaction temperature of sodium allyl sulfonate and polyetheramine is 30℃~80℃, and the reaction time is 18h~30h.

[0028] Optionally, in some embodiments of this application, the mass ratio of methyl acrylate-modified amine compound to sodium allyl sulfonate-modified polyetheramine is 1:(1~10); and / or

[0029] The reaction temperature of methyl acrylate-modified amine compounds and sodium allyl sulfonate-modified polyetheramine is 30℃~80℃, and the reaction time is 18h~48h.

[0030] Secondly, this application provides a hyperbranched temperature-resistant and salt-resistant lubricant, which is prepared by the above-described method for preparing a hyperbranched temperature-resistant and salt-resistant lubricant.

[0031] Thirdly, this application also provides the application of the above-mentioned hyperbranched, temperature-resistant, and salt-resistant lubricant in the preparation of water-based drilling fluids.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] This application provides a method for preparing a hyperbranched, high-temperature and salt-resistant lubricant. The method involves reacting the double bonds of methyl acrylate with primary and / or secondary amine groups in a polyethylenepolyamine compound to obtain a methyl acrylate-modified amine compound. Since the polyethylenepolyamine compound used in this application contains at least two amino groups, under appropriate reactant ratios, a methyl acrylate-modified amine compound containing multiple ester groups can be obtained. Then, an amino-ester exchange reaction is performed between the amino group at one end of a sodium allyl sulfonate-modified polyetheramine and the methyl acrylate-modified amine compound to obtain the hyperbranched, high-temperature and salt-resistant lubricant. The presence of multiple ester groups endows the methyl acrylate-modified amine compound with multifunctionality, thus the resulting hyperbranched, high-temperature and salt-resistant lubricant possesses a dendritic hyperbranched structure, giving the molecule excellent high-temperature resistance. Furthermore, the abundant polar amide groups formed by the amino-ester exchange reaction endow the hyperbranched, high-temperature and salt-resistant lubricant with stronger adsorption properties, enabling it to stably adsorb onto the surface of metal drill pipes, rocks, and wellbore walls, avoiding direct contact with friction surfaces and significantly reducing frictional resistance. In addition, by introducing polyether segments into the dendritic hyperbranched molecule, this application enables the hyperbranched temperature-resistant and salt-resistant lubricant to have lubrication performance comparable to polyether lubricants and good compatibility with drilling fluids; and by modifying the end groups of the dendritic hyperbranched hyperbranched temperature-resistant and salt-resistant lubricant to sulfonate groups with high salt resistance, this lubricant is endowed with excellent salt resistance. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1This is a flowchart illustrating a method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant, as provided in an embodiment of the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0037] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0038] The structural formulas and molecular weights of some of the chemical reagents used in this application are described below:

[0039] Ethylenediamine: Molecular weight = 60.1;

[0040] Diethylenetriamine: Molecular weight = 103.17;

[0041] Triethylenetetramine: Molecular weight = 146.23;

[0042] Tetraethylenepentamine: Molecular weight = 189.3;

[0043] Methyl acrylate: Molecular weight = 86.09;

[0044] Polyetheramine (D-230): n is 1~5, and the number-average molecular weight is 230;

[0045] Sodium allyl sulfonate: Molecular weight = 144.12.

[0046] The technical solution of this application is as follows:

[0047] Firstly, please refer to Figure 1 This application provides a method for preparing a hyperbranched, high-temperature, and salt-resistant lubricant, comprising the following steps:

[0048] S11. Methyl acrylate and polyethylene polyamine compounds are mixed and reacted to obtain methyl acrylate modified amine compounds;

[0049] S12. Sodium allyl sulfonate and polyetheramine are mixed and reacted to obtain sodium allyl sulfonate-modified polyetheramine.

[0050] S13. The methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyetheramine are mixed and reacted to obtain a hyperbranched, temperature-resistant, and salt-resistant lubricant.

[0051] This application provides a method for preparing a hyperbranched, high-temperature and salt-resistant lubricant. Utilizing the low viscosity, high solubility, and high density of terminal functional groups of dendritic hyperbranched polymers (hyperbranched polyamide-amine), a hyperbranched, high-temperature and salt-resistant lubricant with a dendritic hyperbranched structure is prepared via an amine transesterification reaction. Highly lubricating polyether segments and highly salt-resistant end groups are introduced into the dendritic hyperbranched structure. Combined with the strong adsorption capacity imparted by the abundant amide groups in the dendritic hyperbranched molecule, a hyperbranched, high-temperature and salt-resistant lubricant for drilling fluids with excellent lubrication performance, high-temperature resistance, and salt resistance is obtained.

[0052] In S11:

[0053] In some embodiments, the mixture of methyl acrylate and the polyethylene polyamine compound comprises: a first dispersion and the methyl acrylate, wherein the first dispersion comprises the polyethylene polyamine compound and a first solvent; and the methyl acrylate is added dropwise to the first dispersion.

[0054] In some embodiments, since the polyethylene polyamine compound contains at least two amino groups, it can react with at least four equivalents of methyl acrylate molecules, resulting in a methyl acrylate modified amine compound containing at least four ester groups. This endows the methyl acrylate modified amine compound with multiple reactive sites (functionality), enabling it to subsequently react with multiple modified polyether amine molecules, thereby endowing the hyperbranched temperature-resistant and salt-resistant lubricant molecule with a dendritic hyperbranched structure.

[0055] In some embodiments, the polyethylene polyamine compound is selected from one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0056] In some embodiments, the first solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, trimethoxymethanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0057] In some embodiments, the molar concentration of the polyethylene polyamine compound in the first dispersion is 0.1 mol / L to 1 mol / L, for example, it can be 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, or any range between two values. Within this molar concentration range, uniform dissolution and dispersion of the polyethylene polyamine compound is beneficial.

[0058] In some embodiments, the molar ratio of the polyethylene polyamine compound to the methyl acrylate is 1:(4~20), for example, it can be 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, or any range between two values. Within the range of the molar ratio, it is beneficial for the methyl acrylate to fully undergo an addition reaction with the amino groups in the polyethylene polyamine compound, thereby modifying the polyethylene polyamine compound. It is understood that the molar ratio of the polyethylene polyamine compound to the methyl acrylate can be determined according to the number of reactive groups in the polyethylene polyamine compound. In some embodiments, the polyethylene polyamine compound is ethylenediamine, which has 4 hydrogen atoms that can undergo an addition reaction with the double bond of methyl acrylate. Therefore, the molar ratio of ethylenediamine to methyl acrylate can be 1:4. Preferably, in order to allow the hydrogen atoms of the primary amine group in ethylenediamine to react fully, methyl acrylate can be used in appropriate excess. In this case, the molar ratio of ethylenediamine to methyl acrylate can be 1:4.1, 1:4.2, 1:4.3, 1:4.4, 1:4.5, etc.

[0059] In some embodiments, the reaction temperature between the methyl acrylate and the polyethylene polyamine compound is 25°C to 45°C, for example, 28°C, 30°C, 35°C, 45°C, or any range between two values; the reaction time is 18h to 48h, for example, 20h, 22h, 25h, 28h, 48h, or any range between two values. Thus, under these reaction conditions, it is beneficial for the methyl acrylate and the polyethylene polyamine compound to react efficiently to generate methyl acrylate-modified amine compounds.

[0060] It should be noted that as the number of reactive sites in polyethylene polyamine compounds increases, the kinetic difficulty of reacting all primary and secondary amine groups with methyl acrylate gradually increases. In this case, the reaction temperature can be appropriately increased or the reaction time extended to ensure that the reaction proceeds fully.

[0061] In some embodiments, the structural formula of the methyl acrylate modified amine compound may be selected from one or more of the following formulas:

[0062] , , , .

[0063] It is understandable that the above structures correspond to the structures of methyl acrylate-modified amine compounds generated after the reaction of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine with methyl acrylate.

[0064] In S12:

[0065] In some embodiments, the mixture of sodium allyl sulfonate and polyetheramine comprises: a second dispersion and sodium allyl sulfonate, wherein the second dispersion comprises the polyetheramine and a second solvent; and sodium allyl sulfonate is added dropwise to the second dispersion.

[0066] It is understandable that the amino groups in the sodium allyl sulfonate-modified polyetheramine obtained from the reaction can undergo an amino-ester exchange reaction with the ester groups in the methyl acrylate-modified amine compounds to generate amide groups, thus obtaining a hyperbranched, temperature-resistant, and salt-resistant lubricant with a dendritic branched structure.

[0067] In some embodiments, the polyetheramine contains at least two amino groups. Modification of the polyetheramine with sodium allyl sulfonate retains at least one amino group in the polyetheramine. The retained amino group can react with the ester group in methyl acrylate-modified amine compounds, while the sodium sulfonate group imparts excellent salt resistance to the lubricant molecule.

[0068] It should be noted that the polyetheramine is selected from the D series, ED series, or T series. Among them, the D series is selected from D-230 and D-400; the T series is selected from T-403; and the ED series is selected from ED-600. In the preferred embodiment of the present invention, the polyetheramine of type D-230 is selected. It has low viscosity and low vapor pressure characteristics, which makes the reaction system easy to transfer mass and heat during stirring, avoiding local overheating or uneven reaction. The low molecular weight and methyl side chain of the polyetheramine of D-230 are used to adjust the hydrophilicity-hydrophobicity balance, which is beneficial to the stable dispersion and viscosity of the hyperbranched temperature-resistant and salt-resistant lubricant in the water-based system.

[0069] In some embodiments, the second solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, trimethoxymethanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0070] In some embodiments, the molar concentration of the polyetheramine in the second dispersion is 1 mol / L to 10 mol / L, for example, it can be 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, or any range between two values. Within this molar concentration range, uniform dissolution and dispersion of the polyetheramine are beneficial.

[0071] In some embodiments, the molar ratio of the polyetheramine to the sodium allyl sulfonate is 1:(0.9~1), for example, it can be 1:0.9, 1:0.91, 1:0.92, 1:0.93, 1:0.94, 1:0.95, 1:0.96, 1:0.97, 1:0.98, 1:0.99, 1:1, or any range between two values. Within the range of the molar ratio, it is beneficial for the sodium allyl sulfonate to fully undergo an addition reaction with the amino group in the polyetheramine, and ensures that the polyetheramine molecule has at least one amino group capable of reacting with the ester group.

[0072] In some embodiments, the reaction temperature between the sodium allyl sulfonate and the polyetheramine is 30°C to 80°C, for example, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, or any range between two values; the reaction time is 18h to 48h, for example, 20h, 22h, 25h, 28h, 30h, or any range between two values. Thus, under these reaction conditions, the sodium allyl sulfonate and the polyetheramine react efficiently to produce sodium allyl sulfonate-modified polyetheramine.

[0073] In some embodiments, the structural formula of the sodium allyl sulfonate modified polyetheramine is shown below:

[0074] Where 1≤n≤5.

[0075] In some embodiments, the mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine is 1:(1~10), for example, it can be 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, or any range between two values. Within the range of the mass ratio, it is beneficial for the methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyetheramine to combine effectively, thereby improving the performance of the hyperbranched temperature-resistant and salt-resistant lubricant.

[0076] It is understood that those skilled in the art can reasonably select the mass ratio of methyl acrylate-modified amine compounds and sodium allyl sulfonate-modified polyetheramines based on the functionality (number of ester groups) of the methyl acrylate-modified amine compounds.

[0077] In S13:

[0078] In some embodiments, the reaction temperature between the methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyetheramine is 30°C to 80°C, for example, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, or any range between two values; the reaction time is 18h to 48h, for example, 20h, 22h, 25h, 28h, 48h, or any range between two values. Thus, under these reaction conditions, it is advantageous for the methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyetheramine to react efficiently to produce the sodium allyl sulfonate-modified polyetheramine.

[0079] It should be noted that, since methyl acrylate-modified amine compounds have multiple ester groups, the kinetic difficulty of the complete reaction between sodium allyl sulfonate-modified polyetheramine and methyl acrylate-modified amine compounds depends on the number of ester groups. The more ester groups there are, the greater the steric hindrance effect needs to be overcome in the subsequent transesterification reaction. Therefore, as the number of ester groups in methyl acrylate-modified amine compounds increases, the reaction temperature and reaction time can be appropriately increased to ensure that the amino and ester groups undergo a complete transesterification reaction. If necessary, a catalyst can be used to further lower the activation energy to ensure the reaction proceeds fully. For example, one or more of sodium aminoborane (NaNH2BH3), sodium methoxide (NaOMe), trimethylaluminum (AlMe3), magnesium methoxide (Mg(OMe)2), and the organic base catalyst DBU (1,8-diazabicycloundec-7-ene) can be selected to improve the reactivity.

[0080] In some embodiments, the structural formula of the hyperbranched temperature-resistant and salt-resistant lubricant may be selected from one or more of the following formulas:

[0081] , , ,

[0082] ;

[0083] Where 1≤n≤5.

[0084] Secondly, embodiments of this application provide a hyperbranched temperature-resistant and salt-resistant lubricant, which is prepared by the above-described method for preparing a hyperbranched temperature-resistant and salt-resistant lubricant.

[0085] Thirdly, this application also provides the application of a hyperbranched, temperature-resistant, and salt-resistant lubricant in the preparation of water-based drilling fluids, wherein the water-based drilling fluids include the hyperbranched, temperature-resistant, and salt-resistant lubricant.

[0086] This application provides a hyperbranched, temperature-resistant, and salt-resistant lubricant that can reduce friction between the drill string and the wellbore, thereby reducing drilling resistance and drill string wear to ensure the safety and efficiency of the drilling process.

[0087] In some embodiments, the water-based drilling fluid further includes a base slurry comprising water and sodium clay. The sodium clay has a mass fraction of 3 wt% to 8 wt% in the water, and the hyperbranched, temperature- and salt-resistant lubricant has a mass fraction of 1 wt% to 5 wt% in the water.

[0088] The present application will be specifically described below through specific embodiments. The following embodiments are only some embodiments of the present application and are not intended to limit the present application.

[0089] Example 1

[0090] This embodiment provides a hyperbranched, high-temperature resistant, and salt-resistant lubricant, the preparation method of which includes the following steps:

[0091] Step 1: Weigh 0.05 mol ethylenediamine and 100 g anhydrous methanol into a 250 mL three-necked flask, stir for 5 min, and add 0.3 mol methyl acrylate dropwise through a constant pressure funnel under ice-water bath and nitrogen protection. Heat to 30 °C and react for 24 h under nitrogen atmosphere. After the reaction is complete, the reaction solution is rotary evaporated at 40 °C to remove residual methanol and unreacted methyl acrylate, yielding a yellow oily liquid product (methyl acrylate modified amine compound). Its reaction equation and specific structural formula are shown below:

[0092] ;

[0093] Step 2: Weigh 0.2 mol of polyetheramine D-230 and 100 g of anhydrous ethanol into a 250 mL three-necked flask equipped with a reflux condenser and a constant pressure funnel. Stir at room temperature until the polyetheramine D-230 is completely dissolved. Add 0.2 mol of sodium allyl sulfonate, keep stirring, raise the temperature to 60 °C, and react for 24 h under a nitrogen atmosphere. After the reaction is complete, a modified polyetheramine (sodium allyl sulfonate modified polyetheramine) with two end groups, amino and sodium sulfonate groups, is obtained. The reaction equation and specific structural formula are shown below:

[0094] , where n is 1 to 5;

[0095] Step 3: The methyl acrylate-modified amine compound obtained in Step 1 was added to the sodium allyl sulfonate-modified polyetheramine solution obtained in Step 2 through a constant pressure funnel (wherein the mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine was 1:1). The mixture was heated to 50°C and reacted under a nitrogen atmosphere for 24 hours. After the reaction was completed, the reaction solution was rotary evaporated at 60°C to remove residual ethanol, yielding a pale yellow viscous liquid hyperbranched temperature-resistant and salt-resistant lubricant. The reaction equation and specific structural formula are shown below:

[0096] , where n is 1 to 5.

[0097] Example 2

[0098] This embodiment provides a hyperbranched, high-temperature resistant, and salt-resistant lubricant, the preparation method of which includes the following steps:

[0099] Step 1: Weigh 0.05 mol of diethylenetriamine and 100 g of anhydrous methanol into a 250 mL three-necked flask, stir for 5 min, and add 0.375 mol of methyl acrylate dropwise through a constant pressure funnel under ice-water bath and nitrogen protection. Heat to 35 °C and react for 30 h under nitrogen atmosphere. After the reaction is complete, the reaction solution is rotary evaporated at 40 °C to remove residual methanol and unreacted methyl acrylate, yielding a yellow oily liquid product (methyl acrylate-modified amine compound). Its reaction equation and specific structural formula are shown below:

[0100] ;

[0101] Step 2: Weigh 0.25 mol of polyetheramine D-230 and 100 g of anhydrous ethanol into a 250 mL three-necked flask equipped with a reflux condenser and a constant pressure funnel. Stir at room temperature until the polyetheramine D-230 is completely dissolved. Add 0.25 mol of sodium allyl sulfonate, keep stirring, raise the temperature to 60 °C, and react for 24 h under a nitrogen atmosphere. After the reaction is complete, a modified polyetheramine (sodium allyl sulfonate modified polyetheramine) with two end groups, amino and sodium sulfonate groups, is obtained. The reaction equation and specific structural formula are shown below:

[0102] , where n is 1 to 5;

[0103] Step 3: The methyl acrylate-modified amine compound obtained in Step 1 was added to the sodium allyl sulfonate-modified polyetheramine solution obtained in Step 2 through a constant pressure funnel (wherein the mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine was 1:5). 0.2 g of sodium methoxide (NaOMe) was added, and the mixture was heated to 55°C and reacted under a nitrogen atmosphere for 30 h. After the reaction was complete, the reaction solution was rotary evaporated at 60°C to remove residual ethanol and the byproduct methanol, yielding a pale yellow, viscous, hyperbranched, temperature-resistant, and salt-resistant lubricant. The reaction equation and specific structural formula are shown below:

[0104] , where n is 1 to 5.

[0105] Example 3

[0106] This embodiment provides a hyperbranched, high-temperature resistant, and salt-resistant lubricant, the preparation method of which includes the following steps:

[0107] Step 1: Weigh 0.05 mol of triethylenetetramine and 100 g of anhydrous methanol into a 250 mL three-necked flask, stir for 5 min, and add 0.45 mol of methyl acrylate dropwise through a constant pressure funnel under ice-water bath and nitrogen protection. Heat to 40 °C and react for 36 h under nitrogen atmosphere. After the reaction is complete, the reaction solution is rotary evaporated at 40 °C to remove residual methanol and unreacted methyl acrylate, yielding a yellow oily liquid product (methyl acrylate modified amine compound), the specific structural formula of which is shown below:

[0108] ;

[0109] Step 2: Weigh 0.3 mol of polyetheramine D-230 and 100 g of anhydrous ethanol into a 250 mL three-necked flask equipped with a reflux condenser and a constant pressure funnel. Stir at room temperature until the polyetheramine D-230 is completely dissolved. Add 0.3 mol of sodium allyl sulfonate, keep stirring, raise the temperature to 60 °C, and react for 24 h under a nitrogen atmosphere. After the reaction is complete, a modified polyetheramine (sodium allyl sulfonate modified polyetheramine) with two end groups, an amino group and a sodium sulfonate group, is obtained. Its specific structural formula is shown below:

[0110] , where n is 1 to 5;

[0111] Step 3: The methyl acrylate-modified amine compound obtained in Step 1 was added to the sodium allyl sulfonate-modified polyetheramine solution obtained in Step 2 through a constant pressure funnel (wherein the mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine was 1:6). 0.2 g of sodium methoxide (NaOMe) was added, and the mixture was heated to 60°C and reacted under a nitrogen atmosphere for 36 h. After the reaction was complete, the reaction solution was rotary evaporated at 60°C to remove residual ethanol and the byproduct methanol, yielding a pale yellow, viscous, hyperbranched, temperature-resistant, and salt-resistant lubricant. Its specific structural formula is shown below:

[0112] , where n is 1 to 5.

[0113] Example 4

[0114] This embodiment provides a hyperbranched, high-temperature resistant, and salt-resistant lubricant, the preparation method of which includes the following steps:

[0115] Step 1: Weigh 0.05 mol tetraethylenepentamine and 100 g anhydrous methanol into a 250 mL three-necked flask, stir for 5 min, and add 0.5 mol methyl acrylate dropwise through a constant pressure funnel under ice-water bath and nitrogen protection. Heat to 45 °C and react for 48 h under nitrogen atmosphere. After the reaction is complete, the reaction solution is rotary evaporated at 40 °C to remove residual methanol and unreacted methyl acrylate, yielding a yellow oily liquid product (methyl acrylate modified amine compound), the specific structural formula of which is shown below:

[0116] ;

[0117] Step 2: Weigh 0.35 mol of polyetheramine D-230 and 100 g of anhydrous ethanol into a 250 mL three-necked flask equipped with a reflux condenser and a constant pressure funnel. Stir at room temperature until the polyetheramine D-230 is completely dissolved. Add 0.35 mol of sodium allyl sulfonate, keep stirring, raise the temperature to 60 °C, and react for 24 h under a nitrogen atmosphere. After the reaction is complete, a modified polyetheramine (sodium allyl sulfonate modified polyetheramine) with two end groups, an amino group and a sodium sulfonate group, is obtained. Its specific structural formula is shown below:

[0118] , where n is 1 to 5;

[0119] Step 3: The methyl acrylate-modified amine compound obtained in Step 1 was added to the sodium allyl sulfonate-modified polyetheramine solution obtained in Step 2 through a constant pressure funnel (wherein the mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine was 1:7). 0.3 g of sodium methoxide (NaOMe) was added, and the mixture was heated to 65°C and reacted under a nitrogen atmosphere for 48 h. After the reaction was complete, the reaction solution was rotary evaporated at 60°C to remove residual ethanol and the byproduct methanol, yielding a pale yellow viscous liquid lubricant, the specific structural formula of which is shown below:

[0120] , where n is 1 to 5.

[0121] Comparative Example

[0122] This comparative example provides a lubricant, namely SYP-2, a commercially available polyether polyol lubricant for drilling fluids, which is emulsified from block polymers such as propylene oxide and ethylene oxide with nonionic surfactants (purchased from Shandong Deshunyuan Petroleum Technology Co., Ltd.).

[0123] The hyperbranched, high-temperature resistant, and salt-resistant lubricants from Examples 1 to 4, along with the comparative lubricants, were used to prepare water-based drilling fluids. Their lubrication performance, high-temperature lubrication performance, and salt-resistant lubrication performance were tested. The test results are shown in Table 1.

[0124] The preparation of the freshwater-based slurry is as follows: 400mL distilled water + 20.0g (5wt%) sodium clay, stir at high speed for 20 minutes, and then seal and let stand for hydration at 25℃±1℃ for 24 hours.

[0125] Preparation of saturated brine-based slurry: 400 mL distilled water + 20.0 g (5 wt%) sodium clay, stir at high speed for 20 minutes, add 144 g (36%) sodium chloride, stir at 4000 r / min for 20 minutes at room temperature, and seal and let stand for hydration at 25℃ ±1℃ for 24 hours.

[0126] Each test sample was prepared by mixing 400 mL of base slurry with 4 g (1 wt%) of the lubricant used in Examples 1 to 4 and the comparative examples (before or after high-temperature aging) and stirring at high speed for 20 min.

[0127] The lubrication torque of the base slurry and each test sample was measured using an extreme pressure lubricator. The lubrication coefficient retention rate was calculated based on the difference in torque retention between the test sample and the base slurry. Lubrication coefficient retention rate (%) = (base slurry torque - test sample torque) * 100 / base slurry torque. The high-temperature aging of the lubricants in Examples 1 to 4 and the comparative examples was carried out in a thermal aging test chamber at a temperature of 220°C for 24 hours.

[0128] Table 1 shows the test data for the lubricants in Examples 1-4 and the comparative example.

[0129]

[0130] As shown in Table 1, the hyperbranched temperature-resistant and salt-resistant lubricants provided in Examples 1 to 4 all exhibited higher lubrication coefficient retention rates than the comparative examples, regardless of whether they were used in freshwater-based slurry, saturated freshwater-based slurry, or freshwater-based slurry after high-temperature aging. This indicates that the hyperbranched temperature-resistant and salt-resistant lubricants provided in this application have better lubrication performance, high-temperature lubrication performance, and salt-resistant lubrication performance.

[0131] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0132] Unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0133] Unless otherwise specified, all the technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0134] In this invention, unless otherwise specified, percentage (%) or parts refer to weight percentage or parts relative to the composition.

[0135] In the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc. are used merely as illustrative purposes and do not impose numerical requirements or establish an order.

[0136] In this application, "at least one" means one or more, and "more than one" means two or more. "One or more", "at least one of the following", or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0137] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0138] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant, characterized in that, Includes the following steps: Methyl acrylate and polyethylene polyamine compounds are mixed and reacted to obtain methyl acrylate-modified amine compounds; Sodium allyl sulfonate and polyetheramine are mixed and reacted to obtain sodium allyl sulfonate-modified polyetheramine; The methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyether amine are mixed and reacted to obtain a hyperbranched, temperature-resistant, and salt-resistant lubricant. The polyethylene polyamine compound is selected from one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; The structural formula of the polyetheramine is: , where n is an integer from 1 to 5.

2. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 1, characterized in that, The mixing of methyl acrylate and polyethylene polyamine compounds includes: A first dispersion and the methyl acrylate, wherein the first dispersion comprises the polyethylene polyamine compound and a first solvent; The methyl acrylate is added dropwise to the first dispersion.

3. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 2, characterized in that, The first solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide.

4. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 2, characterized in that, In the first dispersion, the molar concentration of the polyethylene polyamine compound is 0.1 mol / L to 1 mol / L; and / or The molar ratio of the polyethylene polyamine compound to the methyl acrylate is 1:(4~20); and / or The reaction temperature of the methyl acrylate and the polyethylene polyamine compound is 25℃~45℃, and the reaction time is 18h~48h.

5. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 1, characterized in that, The mixing of sodium allyl sulfonate and polyetheramine includes: The second dispersion and the sodium allyl sulfonate, wherein the second dispersion includes the polyether amine and the second solvent; The sodium allyl sulfonate is added dropwise to the second dispersion.

6. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 5, characterized in that, The polyetheramine contains at least two amino groups.

7. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 6, characterized in that, The second solvent is selected from one or more of methanol, ethanol, propylene glycol, butanol, tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide; and / or In the second dispersion, the molar concentration of the polyetheramine is 1 mol / L to 10 mol / L; and / or The molar ratio of the polyetheramine to the sodium allyl sulfonate is 1:(0.9~1); and / or The reaction temperature of the sodium allyl sulfonate and the polyetheramine is 30℃~80℃, and the reaction time is 18h~30h.

8. The method for preparing a hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 1, characterized in that, The mass ratio of the methyl acrylate-modified amine compound to the sodium allyl sulfonate-modified polyetheramine is 1:(1~10); and / or The reaction temperature of the methyl acrylate-modified amine compound and the sodium allyl sulfonate-modified polyetheramine is 30℃~80℃, and the reaction time is 18h~48h.

9. A hyperbranched, temperature-resistant, and salt-resistant lubricant, characterized in that, The hyperbranched temperature-resistant and salt-resistant lubricant is prepared by the preparation method of the hyperbranched temperature-resistant and salt-resistant lubricant according to any one of claims 1 to 8.

10. The application of the hyperbranched, temperature-resistant, and salt-resistant lubricant according to claim 9 in the preparation of water-based drilling fluid.

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