CN107365402B - Preparation method of micro-branched micro-crosslinked polyacrylamide - Google Patents

Preparation method of micro-branched micro-crosslinked polyacrylamide Download PDF

Info

Publication number
CN107365402B
CN107365402B CN201710302688.2A CN201710302688A CN107365402B CN 107365402 B CN107365402 B CN 107365402B CN 201710302688 A CN201710302688 A CN 201710302688A CN 107365402 B CN107365402 B CN 107365402B
Authority
CN
China
Prior art keywords
micro
branched
mass
persulfate
slightly
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201710302688.2A
Other languages
Chinese (zh)
Other versions
CN107365402A (en
Inventor
曹绪龙
郭拥军
祝仰文
窦立霞
刘坤
徐辉
庞雪君
何冬月
李海涛
孙秀芝
李彬
董雯
季青青
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Petroleum and Chemical Corp
Exploration and Development Research Institute of Sinopec Shengli Oilfield Co
Original Assignee
China Petroleum and Chemical Corp
Exploration and Development Research Institute of Sinopec Shengli Oilfield Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Petroleum and Chemical Corp, Exploration and Development Research Institute of Sinopec Shengli Oilfield Co filed Critical China Petroleum and Chemical Corp
Priority to CN201710302688.2A priority Critical patent/CN107365402B/en
Publication of CN107365402A publication Critical patent/CN107365402A/en
Application granted granted Critical
Publication of CN107365402B publication Critical patent/CN107365402B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/52—Amides or imides
    • C08F220/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
    • C08F220/56—Acrylamide; Methacrylamide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/38—Polymerisation using regulators, e.g. chain terminating agents, e.g. telomerisation
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F8/00—Chemical modification by after-treatment
    • C08F8/12—Hydrolysis
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
    • C09K8/588—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids characterised by the use of specific polymers

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

The invention discloses a preparation method of micro-branched micro-crosslinked polyacrylamide, which comprises the following steps: adding acrylamide monomer into water with the mass fraction of 20-30%, then adding dimethylaminoethyl methacrylate, persulfate, chain transfer agent, EDTA and manganese acetylacetonate, adjusting the pH value to 5-8, initiating polymerization reaction at 20-40 ℃, taking out the colloid for granulation after reacting for 5-10 h, then adding NaOH accounting for 1.5-3% of the mass of the colloid, and hydrolyzing for 1-3 h at 80-100 ℃ to obtain the nano-composite material. The slightly-branched slightly-crosslinked polyacrylamide prepared by the method has high viscosity, excellent thermal stability and mechanical shear resistance, and experiments show that the viscosity retention rate of the slightly-branched slightly-crosslinked polyacrylamide after mechanical shear is more than 81 percent, and the viscosity retention rate of the slightly-branched slightly-crosslinked polyacrylamide after aging for 90 days is more than 79 percent. The method has the advantages of mild reaction conditions, simple operation, low cost and the like.

Description

Preparation method of micro-branched micro-crosslinked polyacrylamide
Technical Field
The invention relates to a preparation method of micro-branched micro-crosslinked polyacrylamide, belonging to the technical field of preparation of oilfield chemicals.
Background
The polymer flooding is an important component of the technology for improving the recovery ratio as one of chemical flooding, has clear oil displacement mechanism, simpler process and mature technology, and starts the indoor research work of the polymer flooding in Daqing and Shengli oil fields as early as 60 years. Since 90 s, polymer flooding mine field experiments are carried out in oil fields such as Daqing, Dagang, Shengli and the like on the basis of laboratory researches, a larger polymer production and application scale is formed at home at present, and partially hydrolyzed polyacrylamide is generally adopted as a main oil displacement agent.
However, polymer flooding also exposes problems in implementation, such as: when the polymer solution is deformed or flows during the preparation and the whole oil layer seepage process, the polymer is subjected to mechanical degradation when the shear stress is increased enough to break polymer molecules; during polymer injection in an oil field, the highest flow rates near the injection well will occur, again causing mechanical degradation of the polymer chains, causing a significant reduction in polymer viscosity, and thus affecting the ultimate recovery. At present, the first-class reserves with better oil reservoir conditions are less and less, the high-temperature oil reservoirs are main replacement resources for increasing storage and production in the future for a long time, and the conventional polymer flooding and composite flooding technology cannot meet the requirements of the high-temperature oil reservoirs due to the problems of poor injectivity, low viscosity retention rate of a solution under the high-temperature condition and the like. Therefore, how to improve the temperature resistance and the shear resistance of the polymer in the injection preparation process so as to maintain the viscosity of the polymer to the maximum extent is an important problem to be solved in the polymer flooding design and has very important significance for improving the polymer flooding.
Disclosure of Invention
Aiming at the prior art, the invention provides a preparation method of micro-branched micro-crosslinked polyacrylamide, and the micro-branched micro-crosslinked polyacrylamide prepared by the method has higher viscosity, excellent thermal stability and excellent mechanical shear resistance.
The invention is realized by the following technical scheme:
a preparation method of micro-branched and micro-crosslinked polyacrylamide comprises the following steps: adding an acrylamide monomer into pure water, wherein the mass fraction of the acrylamide monomer is 20-30%, adjusting the temperature to 20-40 ℃, then adding dimethylaminoethyl methacrylate (DMAEMA), persulfate (selected from one of potassium persulfate, ammonium persulfate and sodium persulfate), a chain transfer agent, EDTA and manganese acetylacetonate, adjusting the pH value of a reaction system to 5-8 by using glacial acetic acid, initiating a polymerization reaction at the temperature of 20-40 ℃, taking out a colloid for granulation after fully reacting for 5-10 h, then adding a hydrolytic agent NaOH accounting for 1.5-3% (preferably 2.5%) of the mass of the colloid, and hydrolyzing for 1-3 h at the temperature of 80-100 ℃ to obtain polyacrylamide with a micro-branched micro-crosslinked structure; wherein the addition amount of the persulfate is 0.05-0.2% of the mass of the acrylamide monomer; the adding amount of the chain transfer agent is 0.02 to 0.3 percent of the mass of the acrylamide monomer; the addition amount of the EDTA is 0.005-0.05 percent of the mass of the acrylamide monomer; the addition amount of the manganese acetylacetonate is 0.01-0.1 percent of the mass of the acrylamide monomer; the molar ratio of dimethylaminoethyl methacrylate to persulfate is 1-8: 1; the chain transfer agent is selected from sodium formate, isopropanol, dodecyl mercaptan, octadecyl mercaptan.
Preferably, the addition amount of the persulfate is 0.1-0.12% of the mass of the acrylamide monomer.
Preferably, the addition amount of the manganese acetylacetonate is 0.04-0.06% of the optimal addition amount of the mass of the acrylamide monomer.
Preferably, the molar ratio of the dimethylaminoethyl methacrylate to the persulfate is 3-4: 1.
The slightly-branched slightly-crosslinked polyacrylamide prepared by the method has the following structural formula:
Figure BDA0001284546100000021
wherein m and n are the number of acrylamide repeating units, and m and n are respectively 1 × 104～1×105Is an integer of (1).
The micro-branched micro-crosslinked polyacrylamide disclosed by the invention has good shear resistance and thermal stability. Experiments show that the viscosity retention rate of the slightly-branched and slightly-crosslinked polyacrylamide after mechanical shearing is more than 81%, and the viscosity retention rate is more than 79% after aging for 90 d.
The preparation method of the micro-branched micro-crosslinked polyacrylamide provided by the invention takes persulfate and dimethylaminoethyl methacrylate (DMAEMA) as an initiating system, and adds manganese acetylacetonate at the same time, and adopts conventional free radical polymerization in an aqueous solution to prepare the polyacrylamide with a micro-branched micro-crosslinked structure. The dimethylaminoethyl methacrylate (DMAEMA) contains double bonds, can participate in the reaction and also can be used as a reducing agent in an initiation system, and the molecular weight of the polymer can be improved by adding manganese acetylacetonate. The DMAEMA is used as a reducing agent to perform single-electron transfer oxidation-reduction reaction with persulfate, an initiation active point can be formed on secondary carbon adjacent to nitrogen, free radical polymerization is further initiated to form a long branched chain, and manganese acetylacetonate can promote free radical coupling termination at a chain end to form a cross-linked structure, so that a micro-branched micro-cross-linked structure is finally formed. The method has the advantages of mild reaction conditions, simple operation and lower cost, and can effectively improve the thermal stability and the anti-shearing performance of the polyacrylamide.
In order to improve the thermal stability and the shear resistance of the polymer, the chemical structure of the polymer is properly improved, the improved polymer has a micro-branching and micro-crosslinking structure, the polymer molecules have higher molecular weight, which means that the improved polymer has good tackifying capability, when the improved polymer is subjected to strong shearing action, the shear degradation mainly occurs on branched chains, a small amount of branched chains are broken, the influence on the main molecular structure is small, and the viscosity of a system cannot be obviously influenced, so that the good shear resistance can greatly improve the viscosity of the underground working fluid. After the molecular structure is properly designed, the rigidity of a polymer molecular chain can be improved, the difficulty of molecular conformation transition is increased, and the thermal stability of the polymer is improved.
Drawings
FIG. 1: the structural formula of the micro-branched micro-crosslinked polyacrylamide is shown in the specification, wherein m and n are the number of acrylamide repeating units, and m and n are respectively 1 multiplied by 104～1×105Is an integer of (1).
FIG. 2: the reaction formula of the slightly branched and slightly crosslinked polyacrylamide is shown in the specification, wherein m and n are the number of acrylamide repeating units, and m and n are respectively 1 x 104～1×105Is an integer of (1).
FIG. 3: nuclear magnetic resonance hydrogen spectrum of the micro-branched and micro-crosslinked polyacrylamide.
FIG. 4: infrared spectrogram of the slightly branched and slightly crosslinked polyacrylamide.
Detailed Description
The present invention will be further described with reference to the following examples.
The instruments, reagents, materials and the like used in the following examples are conventional instruments, reagents, materials and the like in the prior art and are commercially available in a normal manner unless otherwise specified. Unless otherwise specified, the experimental methods, detection methods, and the like described in the following examples are conventional experimental methods, detection methods, and the like in the prior art.
EXAMPLE 1 preparation of slightly branched slightly crosslinked Polyacrylamide
The method comprises the following steps: adding 400g of pure water into a 500ml beaker, adding 100g of acrylamide monomer, fully stirring, putting the beaker into a 40 ℃ water bath, keeping the temperature until the solution temperature is 40 ℃, and then sequentially adding dimethylaminoethyl methacrylate, ammonium persulfate, sodium formate, EDTA and manganese acetylacetonate, wherein the molar ratio of dimethylaminoethyl methacrylate to ammonium persulfate is 4:1, the adding amount of ammonium persulfate is 0.1% of the mass of the acrylamide monomer, the adding amount of sodium formate is 0.05% of the mass of the acrylamide monomer, the adding amount of EDTA is 0.02% of the mass of the acrylamide monomer, and the adding amount of manganese acetylacetonate is 0.04% of the mass of the acrylamide monomer; adjusting the pH value of the system to be 7, carrying out polymerization reaction in a heat insulation environment, taking out the colloid after fully reacting for 6h, granulating, adding a hydrolytic agent NaOH accounting for 2.5 percent of the total mass of the colloid, uniformly mixing, transferring the mixture into a plastic bag, sealing, and hydrolyzing for 2h in a constant-temperature oven at the constant temperature of 95 ℃. After hydrolysis, putting the colloid into an oven, drying at the constant temperature of 90 ℃ for 2h, taking out, crushing and sieving to obtain polymer dry powder (the structural formula is shown in figure 1, and the reaction formula is shown in figure 2), wherein the nuclear magnetic resonance hydrogen spectrum is shown in figure 3, and the infrared spectrum is shown in figure 4.
FIG. 3 is of slightly branched micro-crosslinked PAM1The HNMR spectrum shows that methylene (m) and methine (n) which alternately appear on the main chain respectively show peaks near chemical shifts 1.58 and 2.12ppm, and the methyl (d) on the DMAEMA structural unit shows a peak which is superposed with the peak at the main chain m. The peaks at a and c in the DMAEMA structural unit are at 2.84ppm and 3.81 ppm; the peak at 3.20ppm is caused by methylene groups (at b) on carbon atoms adjacent to the nitrogen atom on the upper portion of DMAEMA which has not reacted with the oxidant; the peak at 3.10ppm is the methine (g position) formed by redox reaction between the carbon atom adjacent to the nitrogen atom and the oxidant, and since the carbon atom at the position is changed from secondary carbon to tertiary carbon after the reaction forms a branch point and the grafting unit is methylene for supplying electrons, the influence of shielding effect on hydrogen at the g position is increased, and the chemical shift is shifted to 3.10ppm in the low field direction. The ratio of the integrated area of c to (b + g) is 1:0.81, less than 1, demonstrating that part of the methylene groups at b on DMAEMA are oxidized to generate methine groups, which in turn form branching points where coupling termination results in the formation of micro-crosslinked structures when a large number of living chain end diradicals terminate.
FIG. 4 is an infrared spectrum of a slightly branched and slightly crosslinked PAM, from which it can be seen that 3476cm-1Is N-Antisymmetric stretching vibration peak and symmetric stretching vibration peak of H bond, 1654cm-1The peak of the expansion and contraction vibration of the amide I with C ═ O is 1320cm-1Is the stretching vibration peak of the C-N bond, 1451cm-1Is the bending vibration peak of methylene and methyl, 2926cm-1Is the methylene stretching vibration peak, 1383cm-1Is the stretching vibration peak of methyl group in DMAEMA, 1120cm-1The results are the stretching vibration peak of C-O of the ester group, and prove that DMAEMA participates in the polymerization reaction.
Example 2: the polymerization process and procedure of example 1 were followed except that: the molar ratio of dimethylaminoethyl methacrylate to ammonium persulfate is 1: 1. Other polymerization conditions were unchanged.
Example 3: the polymerization process and procedure of example 1 were followed except that: ammonium persulfate is changed into potassium persulfate, and the molar ratio of the dimethylaminoethyl methacrylate to the potassium persulfate is 3: 1. Other polymerization conditions were unchanged.
Example 4: the polymerization process and procedure of example 1 were followed except that: the addition of ammonium persulfate is changed to account for 0.2 percent of the mass of the acrylamide monomer. Other polymerization conditions were unchanged.
Example 5: the polymerization process and procedure of example 1 were followed except that: the addition of manganese acetylacetonate is changed to be 0.01 percent of the mass of the acrylamide monomer. Other polymerization conditions were unchanged.
Example 6: the polymerization process and procedure of example 1 were followed except that: the addition of manganese acetylacetonate is changed to be 0.06 percent of the mass of the acrylamide monomer. Other polymerization conditions were unchanged.
Comparative example 1: the polymerization process and procedure of example 1 were followed except that: no dimethylaminoethyl methacrylate was added to the initiation system.
Comparative example 2: the polymerization process and procedure of example 1 were followed except that: manganese acetylacetonate was not added to the initiation system.
Comparative example 3: the polymerization process and procedure of example 1 were followed except that: no dimethylaminoethyl methacrylate or manganese acetylacetonate is added in the initiation system.
The viscosity average molecular weight of the polymers in the above examples and comparative examples was measured and calculated in GB/T12005.10-92 using an Ubbelohde viscometer (0.55mm tube diameter). The apparent viscosity was determined using pure water in a solution prepared at 1750mg/L of polymer by means of a Brookfield LV DV-III viscometer at a constant speed of 18.8s-1And the temperature is 30 ℃.
And (3) testing the shearing resistance: preparing 1750mg/L polymer solution with pure water, shearing a certain amount of polymer solution with a warning stirrer at 3500r/min shear rate for 120s, and measuring the viscosity of the polymer solution before and after shearing with a Brookfield LV DV-III viscometer (the shear rate is 18.8 s)-1The measurement temperature was 30 ℃.
Testing thermal stability: in the absence of oxygen, a polymer solution prepared from pure water and having a concentration of 1750mg/L was aged at 90 ℃ to measure the viscosity of the polymer before and after 90 days, and the viscosity retention rate was calculated.
The results are shown in Table 1.
TABLE 1 Polymer Properties in examples and comparative examples
Figure BDA0001284546100000051
As can be seen from Table 1, the conventional polyacrylamide of comparative example 3 has a large viscosity loss and a small viscosity retention after mechanical shearing and aging. The slightly-branched and slightly-crosslinked polyacrylamide prepared in each embodiment has large molecular weight and apparent viscosity of a solution, the retention rate of polymerization viscosity after mechanical shearing is more than 81%, and the shearing resistance of the polymer is good. The viscosity retention rate of the slightly-branched and slightly-crosslinked polyacrylamide in each example after being aged for 90d is more than 79%, which indicates that the obtained polymer has good thermal stability.
Although the specific embodiments of the present invention have been described with reference to the examples, the scope of the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications and variations can be made without inventive effort by those skilled in the art based on the technical solution of the present invention.

Claims (6)

1. A preparation method of micro-branched and micro-crosslinked polyacrylamide is characterized by comprising the following steps: adding an acrylamide monomer into water, wherein the mass fraction of the acrylamide monomer is 20-30%, adjusting the temperature to 20-40 ℃, then adding dimethylaminoethyl methacrylate, persulfate, a chain transfer agent, EDTA and manganese acetylacetonate, adjusting the pH value of a reaction system to 5-8, initiating a polymerization reaction at the temperature of 20-40 ℃, taking out a colloid after fully reacting for 5-10 h, granulating, then adding NaOH accounting for 1.5-3% of the mass of the colloid, and hydrolyzing at 80-100 ℃ for 1-3 h to obtain polyacrylamide with a micro-branched micro-crosslinked structure;
wherein the addition amount of the persulfate is 0.05-0.2% of the mass of the acrylamide monomer;
the adding amount of the chain transfer agent is 0.02 to 0.3 percent of the mass of the acrylamide monomer;
the addition amount of the EDTA is 0.005-0.05 percent of the mass of the acrylamide monomer;
the addition amount of the manganese acetylacetonate is 0.01-0.1 percent of the mass of the acrylamide monomer;
the molar ratio of dimethylaminoethyl methacrylate to persulfate is 1-8: 1;
the persulfate is selected from potassium persulfate, ammonium persulfate and sodium persulfate;
the chain transfer agent is selected from sodium formate, isopropanol, dodecyl mercaptan, octadecyl mercaptan.
2. The method for preparing micro-branched and micro-crosslinked polyacrylamide according to claim 1, wherein: the addition amount of the persulfate is 0.1-0.12% of the mass of the acrylamide monomer.
3. The method for preparing micro-branched and micro-crosslinked polyacrylamide according to claim 1, wherein: the addition of the manganese acetylacetonate is 0.04-0.06% of the optimal addition of the mass of the acrylamide monomer.
4. The method for preparing micro-branched and micro-crosslinked polyacrylamide according to claim 1, wherein: the molar ratio of the dimethylaminoethyl methacrylate to the persulfate is 3-4: 1.
5. The method for preparing micro-branched and micro-crosslinked polyacrylamide according to claim 1, wherein: the addition of NaOH is 2.5% of the mass of the colloid.
6. A slightly branched and slightly crosslinked polyacrylamide is characterized in that: is prepared by the preparation method of any one of claims 1 to 5.
CN201710302688.2A 2017-05-02 2017-05-02 Preparation method of micro-branched micro-crosslinked polyacrylamide Active CN107365402B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710302688.2A CN107365402B (en) 2017-05-02 2017-05-02 Preparation method of micro-branched micro-crosslinked polyacrylamide

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710302688.2A CN107365402B (en) 2017-05-02 2017-05-02 Preparation method of micro-branched micro-crosslinked polyacrylamide

Publications (2)

Publication Number Publication Date
CN107365402A CN107365402A (en) 2017-11-21
CN107365402B true CN107365402B (en) 2020-05-12

Family

ID=60304317

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710302688.2A Active CN107365402B (en) 2017-05-02 2017-05-02 Preparation method of micro-branched micro-crosslinked polyacrylamide

Country Status (1)

Country Link
CN (1) CN107365402B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108753267B (en) * 2018-05-25 2020-08-07 成都理工大学 Superhigh temperature resistant anionic polymer fluid loss additive for drilling fluid and completion fluid and preparation method thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101864031A (en) * 2010-05-07 2010-10-20 华南理工大学 Method for preparing temperature control variable viscosity acid gelating agent by aqueous solution polymerization
CN102372818B (en) * 2010-08-23 2013-10-16 中国石油化工股份有限公司 Temperature and salt resistant copolymer for oil field and preparation method thereof

Also Published As

Publication number Publication date
CN107365402A (en) 2017-11-21

Similar Documents

Publication Publication Date Title
CN109971451B (en) Graphene oxide nano cross-linking agent for fracturing fluid and preparation method thereof
CN104844765B (en) A kind of dissaving polymer oil displacement agent and preparation method thereof
CN103910830B (en) A kind of water-soluble branched polymer and preparation method thereof and application
CN104877079A (en) Water-soluble hyperbranched multi-arm polyacrylamide polymer and preparation method thereof
CN115368505A (en) Temperature-resistant salt-resistant water-soluble hydrophobic association polymer oil displacement agent and preparation method thereof
CN113321824A (en) Oil displacement polymer crosslinked by dynamic covalent bond and preparation method thereof
CN105461855B (en) A kind of hydrophobic associated polymer and preparation method thereof
CN113185630A (en) Biodegradable salt-tolerant thickening system and preparation method and application thereof
CN107365402B (en) Preparation method of micro-branched micro-crosslinked polyacrylamide
CN113583177B (en) Preparation method and application of temperature-resistant and salt-resistant six-arm star polyacrylamide
CN113831482A (en) CO based on tertiary amine group2Responsive tackifying polymer and preparation method and application thereof
CN104140790A (en) Water-soluble polymer tackifier for oilfield and preparation method thereof
CN108144551B (en) Polymerizable hyperbranched surfactant and preparation method thereof
CN114763394B (en) Nonionic hyperbranched hydrophobically associating polyacrylamide thickener and preparation method thereof
CN112876629B (en) Oil displacement agent, and synthesis method and application thereof
CN111925477B (en) Preparation method of fluorine-containing thickening agent capable of thickening hydrochloric acid solution
CN104250339A (en) Acrylamide copolymer and its preparation method and use
CN113150758A (en) pH-sensitive temporary plugging agent, preparation method thereof and application thereof in low-permeability reservoir exploitation
CN108530645B (en) Amphiphilic dendritic unsaturated monomer and preparation method and application thereof
CN110790860A (en) Acrylamide copolymer and preparation method and application thereof
CN115991986B (en) Oil displacement agent for oil field and preparation method thereof
CN113234196B (en) Self-adaptive controllable liquid rubber plug and preparation method and application thereof
CN115991846B (en) Clean residue-free acid liquor thickener and preparation method thereof
CN116693429B (en) Variable viscosity amphiphilic structure type fracturing fluid thickener and preparation method and application thereof
CN110229272B (en) Hydrophobic association polymer and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant