A nano-molybdenum disulfide modified polymer and a preparation method and application thereof

Abstract

The present application relates to a kind of nanometer molybdenum disulfide modified polymer and its preparation method and application.Acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropane sulfonic acid (AMPS), high dispersing performance silane modified nanometer molybdenum disulfide (MoS2) are used as polymer monomer, in the presence of initiator and deionized water as solvent, copolymerization is carried out, and high dispersibility nanometer molybdenum disulfide modified polymer is obtained after reaction.The polymer can effectively reduce the viscosity of heavy oil, reduce the water oil mobility ratio of water flooding heavy oil, improve the oil displacement effect, and can be used as the enhanced oil recovery chemical agent of heavy oil reservoir.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil displacement agents for oil production, and particularly relates to a high-dispersibility nano-molybdenum disulfide modified polymer and a preparation method and application thereof. BACKGROUND

[0002] The eastern oilfields in China have entered the stage of high water cut and ultra-high water cut oil production, and it is more and more difficult to maintain stable production and benefits. The tertiary oil recovery technology represented by polymer flooding plays an increasingly important role in the field of improving oil recovery. After more than 50 years of development, the oil displacement polymers have formed a high-efficiency viscosity-increasing system represented by super-high molecular weight partially hydrolyzed polyacrylamide (HPAM) and sulfonated modified polyacrylamide, and an oil displacement system represented by active functional polymer, which has the characteristics of high-efficiency viscosity-increasing and dispersing crude oil. The polymer oil displacement system has achieved good oil displacement effect in the reservoirs with a temperature < 85℃, a salinity < 3×10 4 mg / L and a crude oil viscosity < 800 mPa·s, and has become an important measure for stabilizing oil and controlling water in high water cut reservoirs. However, for the heavy oil reservoirs with a crude oil viscosity > 800 mPa·s, the conventional polymer oil displacement system has been difficult to meet the performance requirements of efficient oil displacement.

[0003] In view of how to improve the mobility control ability of the polymer in the heavy oil reservoir, the main technical ideas at home and abroad are to introduce water-soluble / oil-soluble viscosity reducers, to further use the conventional polymer for chemical flooding after reducing the viscosity of the heavy oil. Certain enhanced oil recovery effect has been achieved in the field, but the viscosity reduction mechanism of the system for the crude oil is mainly to extract the light components in the crude oil, and the heavy components such as resin and asphaltene still remain in the formation and are difficult to be produced. In recent years, modified molybdenum disulfide, silicon dioxide and graphene nanomaterials have the approximate structure size, are easy to insert and destroy the supermolecular aggregate structure of the heavy oil, and then reduce the viscosity of the heavy oil. The nanomaterial viscosity reducers are generally used in combination with the polymer oil displacement system in the application, and are carried to the oil layer by the high-viscosity displacement medium to interact with the heavy oil, but the chromatographic separation effect exists in the application, the heavy oil in the near-wellbore zone is easily consumed in a large amount, it is difficult to penetrate into the formation and interact with the heavy oil, and the enhanced oil recovery effect is limited to further improvement.

[0004] Therefore, it is an important direction to develop a polymer oil displacement agent with the viscosity reduction effect and the mobility control ability of the nanomaterial. SUMMARY

[0005] The present application aims at the problems of insufficient mobility control ability of the existing polymer flooding system in heavy oil reservoirs and chromatographic separation of the nano viscosity reducer / polymer composite system reducing the enhanced oil recovery effect, and provides a high dispersibility nano molybdenum disulfide modified polymer, a preparation method thereof and application of the high dispersibility nano molybdenum disulfide modified polymer as a flooding agent. The high dispersibility nano molybdenum disulfide modified polymer can meet the requirement of heavy oil viscosity reduction, improve the mobility control performance and improve the heavy oil production effect.

[0006] In view of the problems of easy aggregation of the conventional nano molybdenum disulfide at the oil-water interface, difficulty in deepening into heavy oil, chromatographic separation of the nano viscosity reducer / polymer composite system reducing the enhanced oil recovery effect and the like, the present application innovatively constructs the high dispersibility nano molybdenum disulfide, grafts a surfactant chain segment on the surface of the nano molybdenum disulfide to enhance the dispersion effect in non-polar crude oil components, and further grafts a high molecular polymer chain segment on the surface of the high dispersibility molybdenum disulfide through a silane coupling agent to improve the viscosity increasing effect.

[0007] The high dispersibility nano molybdenum disulfide modified polymer provided by the present application has good heavy oil viscosity reduction effect and mobility control ability, and will not cause chromatographic separation due to the difference in adsorption characteristics of the nano molybdenum disulfide and the polymer under the injection reservoir condition, so that it can effectively enter the deep part of the formation and embed into the supramolecular aggregate structure of colloid and asphaltene of heavy oil after contacting with the heavy oil, thereby reducing the viscosity and improving the heavy oil recovery rate.

[0008] Specifically, the present application relates to the following technical solutions:

[0009] In the first aspect of the present application, a high dispersibility nano molybdenum disulfide modified polymer is provided, which is prepared by copolymerization of acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropane sulfonic acid (AMPS) and high dispersibility silane modified nano molybdenum disulfide (MoS2) as polymer monomers in the presence of an initiator and deionized water as a solvent, and the high dispersibility nano molybdenum disulfide modified polymer is obtained after the reaction.

[0010] Preferably, the molar ratio of acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropane sulfonic acid (AMPS) and high dispersibility silane modified nano molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2=70-90:5-15:1-10:0.01-0.15.

[0011] Preferably, the preparation method of the high dispersibility silane modified nano molybdenum disulfide is as follows: nano molybdenum disulfide particles and a cationic surfactant dispersion liquid are added to a silane coupling agent hydrolysate, and then coupling reaction is carried out after ultrasonic treatment, followed by suction filtration, vacuum drying and grinding to obtain the high dispersibility silane modified nano molybdenum disulfide (MoS2).

[0012] Preferably, the silane coupling agent is dissolved in water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise, and the hydrolyzate of the silane coupling agent is obtained after stirring for 1-5 hours; the nano-molybdenum disulfide particles and the cationic surfactant dispersion liquid are added into the hydrolyzate, ultrasonic dispersion is carried out for 15-30 minutes, coupling reaction is carried out at 20-55℃ for 4-10 hours, suction filtration is carried out, the filter cake is washed with ethanol for 3-5 times, vacuum drying is carried out, and grinding is carried out to obtain the silane-modified nano-molybdenum disulfide (MoS2) with high dispersing performance.

[0013] Preferably, the silane coupling agent can be selected from one or more of vinyl silane, amino silane, epoxy silane, mercapto silane and methacryloyloxy silane.

[0014] Preferably, one or more of octadecylamine hydrochloride, dioctadecylamine hydrochloride, N,N-dimethyl octadecylamine hydrochloride, octadecyldimethylbenzylammonium chloride, dodecyldimethylphenylphosphonium bromide and hexadecyltrimethylammonium bromide.

[0015] Preferably, the cationic surfactant dispersion liquid is an aqueous solution formed by dissolving the cationic surfactant in water.

[0016] In the second aspect of the present application, a preparation method of the nano-molybdenum disulfide modified polymer with high dispersing performance is provided.

[0017] (1) The AM, AA, AMPS and MoS2 are accurately weighed, dissolved in deionized water and placed in a three-necked flask, N2 is introduced and stirring is continuously carried out to make them dissolve;

[0018] (2) The initiator is injected by using a syringe, N2 is introduced and stirring is continuously carried out;

[0019] (3) When the reaction system becomes viscous, the stirring is stopped, then the three-necked flask is sealed and placed for a certain time to obtain a transparent gel product, the product is taken out, cut into small pieces, precipitated and purified with ethanol for three times, vacuum dried, granulated to obtain the nano-molybdenum disulfide grafted copolymer P(AM-co-AA-co-AMPS-co-MoS2), abbreviated as PAMS.

[0020] Preferably, the molar ratio of acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS) and the silane-modified nano-molybdenum disulfide (MoS2) with high dispersing performance is AM:AA:AMPS:MoS2=70-90:5-15:1-10:0.01-0.15.

[0021] Preferably, the mass concentration of the monomer in the solvent deionized water is 15-40%.

[0022] Preferably, the initiator is KPS / AIBI.

[0023] Preferably, the molar ratio of the initiator KPS / AIBI is 1-5:2-3.

[0024] Preferably, the molar ratio of the initiator KPS / AIBI is 2-1.5.

[0025] Preferably, the amount of the initiator is 0.01-0.10% of the total mass of the monomers.

[0026] Preferably, the copolymerization reaction is performed by using a free radical polymerization method at an initiation temperature of 25-65℃.

[0027] Preferably, the KPS / AIB composite initiator system solution is injected by using a syringe.

[0028] Preferably, the three-necked flask is sealed and placed for 6-12h.

[0029] In a third aspect of the present application, the above high-dispersibility nanometer molybdenum disulfide modified polymer is applied in oil extraction.

[0030] The above high-dispersibility nanometer molybdenum disulfide modified polymer is applied in oil displacement agents.

[0031] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0032] (1) The present application adopts a two-step reaction method to modify the surface of nanometer molybdenum disulfide by high dispersibility and silane coupling agent, and prepares a high-dispersibility polymerizable nanometer molybdenum disulfide; and further adopts a free radical copolymerization reaction to synthesize a high-dispersibility nanometer molybdenum disulfide modified polymer.

[0033] (2) The high-dispersibility nanometer molybdenum disulfide modified polymer provided by the present application has the advantages of good thick oil viscosity reduction and water phase viscosity increase, so that the polymer can effectively reduce the viscosity of thick oil, reduce the water-oil mobility ratio of water flooding thick oil, and improve the oil displacement effect, and can be used as a chemical agent for enhancing oil recovery of thick oil reservoirs. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a test result graph of the viscosity reduction effect of the preferred high-dispersibility nanometer molybdenum disulfide modified polymer of the present application.

[0035] Figure 2 It is a test result graph of the temperature resistance effect of another preferred high-dispersibility nanometer molybdenum disulfide modified polymer of the present application. DETAILED DESCRIPTION

[0036] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not considered critical for the purposes of the application. The ranges should be interpreted as being inclusive of the recited values and the individual points within the ranges. For ranges with endpoints, the endpoints are included as well as the individual points within the ranges.

[0037] In a first aspect of the present application, a high-dispersibility nano-molybdenum disulfide modified polymer is provided, which is prepared by copolymerization of acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), and high-dispersibility nano-molybdenum disulfide (MoS2) as polymer monomers in the presence of an initiator and deionized water as a solvent. The high-dispersibility nano-molybdenum disulfide modified polymer is obtained after the reaction.

[0038] Preferably, the molar ratio of acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), and high-dispersibility nano-molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2=70-90:5-15:1-10:0.01-0.15.

[0039] Preferably, the high-dispersibility nano-molybdenum disulfide is prepared by adding a nano-molybdenum disulfide particle and a cationic surfactant dispersion liquid to a silane coupling agent hydrolysate, performing coupling reaction after ultrasonic dispersion, vacuum drying, and grinding to obtain the high-dispersibility nano-molybdenum disulfide (MoS2).

[0040] Preferably, the silane coupling agent is dissolved in water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise. After stirring for 1-5 h, a silane coupling agent hydrolysate is obtained. A nano-molybdenum disulfide particle and a cationic surfactant dispersion liquid are added to the hydrolysate, ultrasonic dispersion is performed for 15-30 min, coupling reaction is performed at 20-55°C for 4-10 h, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain the high-dispersibility nano-molybdenum disulfide (MoS2).

[0041] Preferably, the silane coupling agent can be selected from one or more of vinyl silane, amino silane, epoxy silane, mercapto silane, and methacryloyloxy silane.

[0042] Preferably, the cationic surfactant is selected from one or more of octadecylamine hydrochloride, dioctadecylamine hydrochloride, N,N-dimethyloctadecylamine hydrochloride, octadecyldimethylbenzylammonium chloride, dodecyldimethylphenylphosphonium bromide, and hexadecyltrimethylammonium bromide.

[0043] Preferably, the cationic surfactant dispersion is an aqueous solution of the cationic surfactant dissolved in water.

[0044] The second aspect of the present application provides a preparation method of the high-dispersibility nano-molybdenum disulfide modified polymer, which specifically comprises the following steps:

[0045] (1) accurately weigh AM, AA, AMPS, and MoS2, dissolve them in deionized water in a three-necked flask, and continuously stir under N2 to dissolve them;

[0046] (2) inject the initiator with a syringe, and continuously stir under N2;

[0047] (3) stop stirring when the reaction system becomes viscous, then seal the three-necked flask and place it for a certain period of time to obtain a transparent gel product, cut it into small pieces, precipitate and purify it with ethanol for three times, and vacuum dry and granulate to obtain the nano-silica grafted copolymer P(AM-co-AA-co-AMPS-co-MoS2), abbreviated as PAMS.

[0048] Preferably, the molar ratio of acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropane sulfonic acid (AMPS), and high-dispersibility silane modified nano-molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2=70-90:5-15:1-10:0.01-0.15.

[0049] Preferably, the mass concentration of the monomers in the solvent deionized water is 15-40%.

[0050] Preferably, the initiator is KPS / AIBI.

[0051] Preferably, the molar ratio of the initiator KPS / AIBI is 1-5:2-3.

[0052] Preferably, the molar ratio of the initiator KPS / AIBI is 2:1.5.

[0053] Preferably, the amount of the initiator accounts for 0.01-0.10% of the total mass of the monomers.

[0054] Preferably, the initiation temperature is 25-65℃, and the copolymerization reaction is performed by using the free radical polymerization method.

[0055] Preferably, the KPS / AIB composite initiator system solution is injected with a syringe.

[0056] Preferably, the three-necked flask is sealed and placed for 6-12h.

[0057] In the third aspect, the present application discloses the application of the high-dispersibility nano-molybdenum disulfide modified polymer in oil extraction.

[0058] The application discloses application of the high-dispersity nanometer molybdenum disulfide modified polymer in an oil displacement agent.

[0059] In addition, various technical features described in the foregoing embodiments can be combined in any suitable manner without contradiction, and various possible combinations are not described again in the application to avoid unnecessary repetition.

[0060] In addition, various different embodiments of the application can be combined in any suitable manner without contradiction, and should be considered as disclosed in the application as long as the idea of the application is not deviated.

[0061] The application will be further described below with reference to specific examples.

[0062] In the application, the devices and equipment used are all conventional devices and equipment known in the art and can be purchased.

[0063] In the following examples and comparative examples, various reagents used are all commercially available chemical pure reagents without special instructions.

[0064] Example 1

[0065] Silane coupling agent γ-(methacryloyloxy)propyl trimethoxysilane (KH570) is dissolved in 200 ml of water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise, and a hydrolyzate of KH570 is obtained after stirring for 2.5 h; 10 g of nanometer molybdenum disulfide particles and 5 g of an aqueous dispersion of CTAB are added to the hydrolyzate, ultrasonic dispersion is performed for 15 min, coupling reaction is performed at 35 °C for 6 h, suction filtration is performed, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain silane modified nanometer molybdenum disulfide (MoS2) with high dispersing performance. The reaction formula is shown in the figure.

[0066]

[0067] Example 2

[0068] Silane coupling agent vinyl silane is dissolved in 200 ml of water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise, and a hydrolyzate of KH570 is obtained after stirring for 2.5 h; 10 g of nanometer molybdenum disulfide particles and 5 g of an aqueous dispersion of octadecylamine hydrochloride are added to the hydrolyzate, ultrasonic dispersion is performed for 15 min, coupling reaction is performed at 35 °C for 6 h, suction filtration is performed, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain silane modified nanometer molybdenum disulfide (MoS2) with high dispersing performance.

[0069] Example 3

[0070] The silane coupling agent epoxy silane is dissolved in 200 ml of water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise. After stirring for 2.5 h, a hydrolysis solution of KH570 is obtained. 10 g of nano molybdenum disulfide particles and 5 g of an aqueous dispersion of octadecyl dimethyl benzyl ammonium chloride are added to the hydrolysis solution, ultrasonic dispersion is performed for 15 min, coupling reaction is performed at 35°C for 6 h, suction filtration is performed, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain silane-modified nano molybdenum disulfide (MoS2) with high dispersing performance.

[0071] Example 4

[0072] The silane coupling agent epoxy silane is dissolved in 200 ml of water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise. After stirring for 2.5 h, a hydrolysis solution of KH570 is obtained. 10 g of nano molybdenum disulfide particles and 5 g of an aqueous dispersion of octadecyl dimethyl benzyl ammonium chloride are added to the hydrolysis solution, ultrasonic dispersion is performed for 15 min, coupling reaction is performed at 35°C for 6 h, suction filtration is performed, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain silane-modified nano molybdenum disulfide (MoS2) with high dispersing performance.

[0073] Example 5

[0074] The silane coupling agent epoxy silane is dissolved in 200 ml of water, and then the pH value is adjusted to 4-5 by adding hydrochloric acid dropwise. After stirring for 2.5 h, a hydrolysis solution of KH570 is obtained. 10 g of nano molybdenum disulfide particles and 5 g of an aqueous dispersion of octadecyl dimethyl benzyl ammonium chloride are added to the hydrolysis solution, ultrasonic dispersion is performed for 15 min, coupling reaction is performed at 35°C for 6 h, suction filtration is performed, the filter cake is washed with ethanol for 3-5 times, vacuum drying is performed, and grinding is performed to obtain silane-modified nano molybdenum disulfide (MoS2) with high dispersing performance.

[0075] Example 6

[0076] A method for preparing a high-dispersibility nano molybdenum disulfide modified polymer comprises the following steps:

[0077] Acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and the high-dispersibility silane-modified nano molybdenum disulfide (MoS2) prepared in Example 1 are used as polymerization monomers, and a copolymerization reaction is performed in the presence of an initiator and deionized water as a solvent. After the reaction is completed, a high-dispersibility nano molybdenum disulfide modified polymer is obtained, wherein:

[0078] The molar ratio of acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and the high-dispersibility silane-modified nano molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2=85:10:4.9:0.1.

[0079] The mass concentration of monomers in the solvent deionized water is 25%; as the initiator KPS / AIBI, the amount is 0.05% of the total mass of monomers, the initiation temperature is 43℃, and the copolymerization reaction is carried out by using the free radical polymerization method. The specific synthesis method is as follows:

[0080] Accurately take 0.85mol of AM, 0.1mol of AA, 0.049mol of AMPS, and 0.001mol of the high dispersibility silane modified nanometer molybdenum disulfide (MoS2) prepared in Example 1 are dissolved in 750mL of deionized water in a 2000mL three-necked flask, N2 is introduced and continuously stirred to dissolve;

[0081] The KPS / AIBI (molar ratio 2:1.5) composite initiator system solution is injected by using a syringe, N2 is introduced and continuously stirred;

[0082] When the reaction system becomes viscous, stop stirring, then seal the three-necked flask and place it for 12h, a transparent gel product is obtained, which is cut into small pieces, precipitated and purified with ethanol for three times, vacuum dried and granulated to obtain the high dispersibility nanometer molybdenum disulfide modified polymer PAMS-1.

[0083] Example 7

[0084] The preparation method of the high dispersibility nanometer molybdenum disulfide modified polymer comprises the following steps:

[0085] Acrylamide (AM), acrylic acid (AA), and the high dispersibility silane modified nanometer molybdenum disulfide (MoS2) prepared in Example 1 are used as polymer monomers, and the copolymerization reaction is carried out in the presence of an initiator and deionized water as a solvent, and the high dispersibility nanometer molybdenum disulfide modified polymer is obtained after the reaction, wherein:

[0086] The molar ratio of acrylamide (AM), acrylic acid (AA), and the high dispersibility silane modified nanometer molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2=85:14.9:0.1.

[0087] The mass concentration of monomers in the solvent deionized water is 25%; as the initiator KPS / AIBI, the amount is 0.05% of the total mass of monomers, the initiation temperature is 43℃, and the copolymerization reaction is carried out by using the free radical polymerization method. The specific synthesis method is as follows:

[0088] Accurately take 0.85mol of AM, 0.149mol of AA, and 0.001mol of MoS2 are dissolved in 750mL of deionized water in a 2000mL three-necked flask, N2 is introduced and continuously stirred to dissolve;

[0089] The KPS / AIBI (molar ratio 2:1.5) complex initiator system solution was injected with a syringe, and N2 was continuously bubbled while stirring;

[0090] When the reaction system became viscous, stirring was stopped, and then the three-necked flask was sealed and placed for 12 h to obtain a transparent gel product. The product was cut into small pieces, precipitated and purified with ethanol three times, vacuum dried, and granulated to obtain the high-dispersion nano-molybdenum disulfide modified polymer PAMS-2.

[0091] Test Example 1

[0092] The viscosity-average molecular weights of the high-dispersion nano-molybdenum disulfide modified polymers PAMS-1 and PAMS-2 prepared in Examples 6 and 7 were determined according to the GB12005.10-92 standard.

[0093] The specific results are as follows:

[0094] Sample Viscosity average molecular weight PAMS-1 7.8 million PAMS-2 12.5 million

[0095] Test Example 2

[0096] The viscosity-reducing effect of the high-dispersion nano-molybdenum disulfide modified polymer PAMS-1 prepared in Example 6 was tested. First, PAMS-1 was prepared into a 0.2% mass fraction aqueous solution, and mixed with a 7000 mPa·s viscous oil sample at different oil-water ratios. The viscosity-reducing rate and dehydration rate were as follows:

[0097] When the amount of PAMS-1 was 10%, the viscosity of the crude oil was reduced from 7000 mPa·s to 330 mPa·s, and the viscosity-reducing rate was 95.28%, which had a good viscosity-reducing effect on the viscous oil. When the amount of PAMS-1 was 80%, the viscosity-reducing rate was 99.31%, and it had a good carrying capacity for crude oil.

[0098] Oil to water ratio Viscosity / mPa-s Viscosity reduction rate / % 20:80 49 99.31 30:70 55 99.23 40:60 63 99.12 50:50 71 99.01 40:60 80 98.89 70:30 92 98.72 80:20 137 98.09 90:10 330 95.28 100:0 7000 0

[0099] Test Example 3

[0100] The viscosity-reducing effect of the high-dispersion nano-molybdenum disulfide modified polymer PAMS-2 prepared in Example 7 was tested at 65°C. First, PAMS-2 was prepared into a 0.2% mass fraction aqueous solution, and mixed with a 7000 mPa·s viscous oil sample at different oil-water ratios. The viscosity-reducing rate and dehydration rate were as follows: Figure 1As shown, the viscosity reduction effect of 0.05% of the high-dispersibility nanometer molybdenum disulfide modified polymer on crude oil is 87.9%, and the dehydration rate is 95.1%. When the concentration of the polymer reaches 0.16%, the viscosity reduction rate reaches 98.8%, and the dehydration rate is 83.1%, indicating that the high-dispersibility nanometer molybdenum disulfide modified polymer PAMS-2 prepared in Example 3 has a significant viscosity reduction effect on thick oil, and as the concentration increases, the dispersion capacity of thick oil is improved to a certain extent.

[0101] Test Example 4

[0102] The temperature resistance of the high-dispersibility nanometer molybdenum disulfide modified polymer PAMS-1 prepared in Example 6 was tested. First, PAMS-2 was prepared into a 0.2% mass fraction aqueous solution, and mixed with a thick oil sample with a viscosity of 7000 mPa·s at different oil-water ratios at 65℃, and the viscosity of the system at different temperatures was tested. The results are shown in Figure 2

[0103] When the temperature exceeds 200℃, the viscosity of the system increases significantly, indicating that the high-dispersibility nanometer molybdenum disulfide modified polymer PAMS-1 has good stability when the temperature is lower than 200℃. When the temperature is higher than this temperature, the viscosity reducer molecules adsorbed on the oil droplet interface decrease, which is not conducive to the formation of the oil-water interface film, and the viscosity of the mixed system increases.

[0104] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application, and all fall within the protection scope of the present application.​

Claims

1. A highly dispersible nano-molybdenum disulfide modified polymer, characterized in that, Using acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and highly dispersible silane-modified molybdenum disulfide nanoparticles (MoS2) as monomers, a copolymerization reaction was carried out in the presence of an initiator and deionized water as a solvent. After the reaction, a highly dispersible molybdenum disulfide nanoparticle-modified polymer was obtained. The molar ratio of molybdenum disulfide (MoS2) is AM:AA:AMPS:MoS2 = 70~90:5~15:1~10:0.01~0.

15. The preparation method of highly dispersible silane-modified nano-molybdenum disulfide is as follows: add nano-molybdenum disulfide particles and cationic surfactant dispersion to the hydrolysate of silane coupling agent, perform coupling reaction after sonication, filter, vacuum dry, and grind to obtain highly dispersible silane-modified nano-molybdenum disulfide (MoS2). The silane coupling agent is KH570.

2. The highly dispersible nano-molybdenum disulfide modified polymer as described in claim 1, characterized in that, A silane coupling agent was dissolved in water, and the pH was adjusted to 4-5 by adding hydrochloric acid dropwise. After stirring for 1-5 hours, a hydrolysate of the silane coupling agent was obtained. Nano-molybdenum disulfide particles and a cationic surfactant dispersion were added to the hydrolysate, and the mixture was ultrasonically dispersed for 15-30 minutes. The coupling reaction was carried out at 20-55℃ for 4-10 hours. The mixture was then filtered, the filter cake was washed with ethanol 3-5 times, vacuum dried, and ground to obtain silane-modified nano-molybdenum disulfide (MoS2) with high dispersibility.

3. The highly dispersible nano-molybdenum disulfide modified polymer as described in claim 2, characterized in that, The cationic surfactant is one or more of octadecylamine hydrochloride, bis(octadecylamine) hydrochloride, N,N-dimethyloctadecylamine hydrochloride, octadecyldimethylbenzylammonium chloride, dodecyldimethylphenylphosphonium bromide, and hexadecyltrimethylammonium bromide.

4. The highly dispersible nano-molybdenum disulfide modified polymer as described in claim 3, characterized in that, The cationic surfactant dispersion is an aqueous solution formed by dissolving a cationic surfactant in water.

5. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer according to any one of claims 1-4, characterized in that, Includes the following steps: (1) Accurately weigh AM, AA, AMPS, and highly dispersible silane-modified nano molybdenum disulfide (MoS2) and dissolve them in deionized water in a three-necked flask. Pass N2 through the flask and stir continuously to dissolve the substances. (2) Inject the initiator with a syringe and continuously stir while introducing N2; (3) When the reaction system becomes viscous, stop stirring, then seal the three-necked flask and let it stand for a certain time to obtain a transparent gel-like product. Take it out and cut it into small pieces, precipitate and purify it three times with ethanol, and then dry it under vacuum and granulate it to obtain nano-silica graft copolymer polymer P(AM-co-AA-co-AMPS-co-MoS2), abbreviated as PAMS.

6. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 1, characterized in that, The monomer has a mass concentration of 15-40% in the solvent deionized water.

7. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 5, characterized in that, The initiator is KPS / AIBI.

8. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 7, characterized in that, The molar ratio of the initiator KPS / AIBI is 1-5:2-3.

9. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 8, characterized in that, The molar ratio of the initiator KPS / AIBI is 2:1.

5.

10. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 5, characterized in that, The initiator is used in an amount of 0.01 to 0.10% of the total mass of the monomer.

11. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 5, characterized in that, Initiator injection is performed at an initiation temperature of 25-65℃, and copolymerization is carried out using free radical polymerization.

12. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 11, characterized in that, Inject the KPS / AIB composite initiation system solution using a syringe.

13. The method for preparing the highly dispersible nano-molybdenum disulfide modified polymer as described in claim 11, characterized in that, Stop stirring the reaction system and seal the three-necked flask for 6-12 hours.

14. The application of the highly dispersible nano-molybdenum disulfide modified polymer as described in any one of claims 1-4 in oil production.

15. The application of the highly dispersible nano-molybdenum disulfide modified polymer as described in any one of claims 1-4 in oil displacement agents in oil production.

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