CN104250337B

CN104250337B - A kind of acrylamide based copolymer and its preparation method and application

Info

Publication number: CN104250337B
Application number: CN201310267753.4A
Authority: CN
Inventors: 杜凯; 张文龙
Original assignee: Sinopec Beijing Research Institute of Chemical Industry; China Petroleum and Chemical Corp
Current assignee: Sinopec Beijing Research Institute of Chemical Industry; China Petroleum and Chemical Corp
Priority date: 2013-06-28
Filing date: 2013-06-28
Publication date: 2016-06-29
Anticipated expiration: 2033-06-28
Also published as: CN104250337A

Abstract

The invention discloses a kind of acrylamide based copolymer and its preparation method and application.Described acrylamide based copolymer contains construction unit A, construction unit B, construction unit C and construction unit D, wherein, described construction unit A is the construction unit shown in formula (1), described construction unit B is the construction unit shown in formula (2), described construction unit C is the construction unit shown in formula (3), and described construction unit D is the construction unit shown in formula (4)；The viscosity-average molecular weight of described acrylamide based copolymer is 5,000,000-1,500 ten thousand.Acrylamide based copolymer drag reducing efficiency provided by the invention is high, salt tolerance high shear performance high, anti-is good, good water solubility and clay stabilizer have good compatibility and formation damage is low.

Description

A kind of acrylamide based copolymer and its preparation method and application

Technical field

The present invention relates to the application as drag reducer of a kind of acrylamide based copolymer, two kinds of preparation methoies of acrylamide based copolymer and described acrylamide based copolymer.

Background technology

The exploitation of Typical Representative shale gas (oil) resource utilized as unconventional petroleum resources has become as a revolution in unconventional petroleum resources field, the whole world, and the development and utilization of current shale gas has become countries in the world and paid close attention to emphatically and the focus technology developed.Due to the ultimate attainment close oil-gas reservoirs such as shale gas reservoir there is permeability extremely low (being generally less than 0.5mD), frac pressure is high, easily cause the feature of formation damage." drag reduction water (slippery water) pressure break " technique must be adopted to exploit.

" drag reduction water (slippery water) pressure break " is the one of fracturing.Compared with conventional pressure break system (modifyed guar gum cross-linking system) at present, drag reduction water (slippery water) pressure break does not rely on high viscosity colloid and takes sand, but takes sand with high infusion discharge capacity, it is achieved reservoir fracturing reticulates the final purpose in crack.Compared with conventional pressure break system, drag reduction water (slippery water) pressure break is less to the injury on stratum while having greater advantage on cost.

Drag reduction water fracturing fluid core auxiliary agent is water-based drag reducer, in practice of construction, the addition of water-based drag reducer overcomes working solution frictional resistance in pipeline, ensure that the raising of infusion discharge capacity, make pressure act on to greatest extent press off stratum and extend formation fracture, currently available make water-based drag reducer mainly have guanidine glue and derivant, cellulose derivative, acrylamide copolymer.

At present, frictional resistance (the US5697444 that drag reducer in adopting guanidine glue, cellulose and its derivates to split as drag reduction hydraulic pressure improves infusion discharge capacity to a certain extent, reduces in pipeline, US5271466), but still the requirement that drag reduction hydraulic pressure splits cannot be met, have the disadvantage in that (1) resistance-reducing performance is limited mainly due to above-mentioned biopolymer；(2) owing to guanidine glue, cellulose and its derivates have a small amount of insoluble matter and very easily stratum damaged；(3) dissolution time is longer.

In drag reduction water pressing crack construction, friction reducer in adopting acrylamide copolymer (partial hydrolysis acrylamide or anionic acrylamide copolymer) to split as drag reduction hydraulic pressure more, greatly enhance infusion discharge capacity, reduce the frictional resistance in pipeline, but the drag reducer split as shale gas reservoir drag reduction hydraulic pressure uses, there is following major defect: (1) " water-sensitive effect " in order to reduce in fracturing process, suppress the hydration swelling of clay composition in shale, little molecular cation clay stabilizer must be added (such as potassium chloride in fracturing fluid, tetramethyl ammonium chloride etc.).Partial hydrolysis acrylamide or anionic acrylamide copolymer and product emulsion thereof and above-mentioned clay stabilization and compatibility poor, very easily produce precipitation；(2) partial hydrolysis acrylamide or anionic acrylamide copolymer use anti-filtration property poor as the drag reducer that shale gas reservoir drag reduction hydraulic pressure splits, and this kind of drag reduction water fracturing fluid very easily leak-off is in the middle of stratum；(3) heat and salt resistance is poor, and especially when high salinity high divalent ion content, molecular structure is unstable, and resistance reducing effect declines very fast.

Patent US20090298721A1 discloses a kind of of the fracturing fluid formula of drag reduction water: add 0.5 gallon of acrylic acidcoacrylamide thing (FR-56 in 1000 gallons of deionized water^TM) etc. anionic acrylamide copolymer emulsion as drag reducer, add the chelating agent such as 0.15wt% sodium carbonate or EDTA-2Na, this drag reduction water fracturing fluid has excellent resistance-reducing performance, indoor average resistance-reducing yield reaches 65.0%, salt tolerance (especially the toleration to divalent calcium ions) there is a degree of improvement, but this kind of drag reduction hydraulic pressure splits system and uses as shale gas drag reduction water fracturing fluid, there are the following problems: (1) and clay stabilizer (such as potassium chloride) and alcohol compatibility poor, very easily produce to precipitate with the alcohol effect such as methanol；(2) anti-filtration property is poor, and this kind of drag reduction water fracturing fluid very easily leak-off is in the middle of stratum；(3) in practice of construction, " water-sensitive effect " is notable；(4) very easily " water blocking " is produced；(5) resistance to high speed shear poor performance, unstable under high speed shear effect, resistance-reducing yield declines quickly；(6) heat-resistant salt-resistant is poor, and especially when high salinity high divalent ion content, molecular structure is unstable, and resistance reducing effect declines very fast；(7) not degradable, it is easy to cause permanent type to injure extremely fine and close shale formation, pollute stratum, then affect oil and gas production.

Compared with above-mentioned partial hydrolysis acrylamide or anionic acrylamide copolymer, the acrylamide copolymer of cationic high-molecular amount is as drag reducer (US356226, US3868328) also have been reported that, this kind of structure copolymer is with better with clay stabilizer (such as the KCl) compatibility, better with the compatibility of alcohol, " water-sensitive effect " is not notable, not easily " water blocking ", but this type of friction reducer macromole is not easy to degraded, it is easy to fine and close shale is caused possible permanent damage.

Therefore, how to improve the resistance to high speed shear performance of drag reducer further, improving fracturing fluid to the inhibition of clay and anti-leak-off, the stability improving the drag reducing efficiency under high salt shear conditions has degradability simultaneously, reduces polymer and the injury on stratum is still a yet unresolved issue.

Summary of the invention

It is an object of the invention to overcome the defect of prior art, there is provided that a kind of drag reducing efficiency is high, salt tolerance high shear performance high, anti-is good, good water solubility and clay stabilizer have good compatibility, there is degradability, and to little acrylamide based copolymer of formation damage and its preparation method and application.

The present invention provides a kind of acrylamide based copolymer, wherein, described acrylamide based copolymer contains construction unit A, construction unit B, construction unit C and construction unit D, wherein, described construction unit A is the construction unit shown in formula (1), described construction unit B is the construction unit shown in formula (2), and described construction unit C is the construction unit shown in formula (3), and described construction unit D is the construction unit shown in formula (4)；And with the total mole number of construction unit in described acrylamide based copolymer for benchmark, the content of described construction unit A is 5-95 mole of %, the content of described construction unit B is 2.5-90 mole of %, the content of described construction unit C is 0.5-90 mole of %, and the content of described construction unit D is 0.0001-1 mole of %；The viscosity-average molecular weight of described acrylamide based copolymer is 5,000,000-1,500 ten thousand；

Wherein, R₁、R₂、R₁₂And R₁₂' it is each independently the alkyl of H or C1-C4；R₃Straight or branched alkylidene for C1-C4；R₄、R₅、R₆、R₁₀、R₁₁、R₁₃、R₁₄、R₁₃' and R₁₄' it is each independently the alkyl of C1-C4；R₇Alkyl for H or C1-C2；R₈For oxygen atom or-NH-；R₉Straight or branched alkylidene for C1-C10；X^-For Cl^-, Br^-, I^-, SCN^-,

The preparation method that the present invention also provides for a kind of acrylamide based copolymer, this preparation method includes when the solution polymerization of alkene, under initiator exists, a kind of monomer mixture is made to carry out polyreaction in water, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in formula (7), described monomer F is the monomer shown in formula (8), described monomer G is the monomer shown in formula (9), described monomer H is the monomer shown in formula (10), in described monomer mixture, the total mole number of monomer is for benchmark, the content of described monomer E is 5-95 mole of %, the content of described monomer F is 2.5-90 mole of %, the content of described monomer G is 0.5-90 mole of %, the content of described monomer H is 0.0001-1 mole of %；After the condition of described solution polymerization makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand,

In addition, the preparation method that the present invention also provides for a kind of acrylamide based copolymer, this preparation method includes aqueous phase and oil phase are mixed to form reversed-phase emulsion, then when emulsion polymerization, under the existence of initiator, this reversed-phase emulsion is carried out polyreaction, described aqueous phase is the aqueous solution containing monomer mixture, described oil phase contains organic solvent and emulsifying agent, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in above-mentioned formula (7), described monomer F is the monomer shown in above-mentioned formula (8), described monomer G is the monomer shown in above-mentioned formula (9), described monomer H is the monomer shown in above-mentioned formula (10), in described monomer mixture, the total mole number of monomer is for benchmark, the content of described monomer E is 5-95 mole of %, the content of described monomer F is 2.5-90 mole of %, the content of described monomer G is 0.5-90 mole of %, the content of described monomer H is 0.0001-1 mole of %；After the condition of described emulsion polymerization makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand.

Additionally, present invention also offers the application as drag reducer of the described acrylamide based copolymer.

In described acrylamide based copolymer provided by the invention, by by the method by copolymerization of the construction unit containing azo group, it is incorporated on the macromolecular chain containing acrylamide construction unit and cationic monomer construction unit, the copolymer of suitable molecular weight is obtained by controlling polymerizing condition, this acrylamide based copolymer is made to have self-degradation, at lower ground layer temperature, (it is generally higher than 60 DEG C) can realize from degraded, the injury to stratum can be reduced, this acrylamide based copolymer has higher drag reducing efficiency under high salt shear conditions simultaneously, and with clay stabilizer (such as KCl and NaCl), there is higher compatibility.Thus obtaining the present invention.

And, the acrylamide based copolymer of present invention water insoluble matter content when as drag reducer is significant lower；The good compatibility is had with cleanup additive (such as methanol).

Specifically, the viscosity-average molecular weight of the acrylamide based copolymer prepared in embodiment 1-6 can reach 500-1500 ten thousand；Insolubles content in water is only 0.01 weight %；Under the shear rate of 2500rpm, this polymer does not produce precipitation at water/alcoholic solution, it is possible to be completely dissolved；The acrylamide based copolymer prepared in embodiment 1-6 is dissolved in NaCl or the KCl solution that concentration is 2 weight %, 4 weight %, 8 weight %, 10 weight %, 12 weight %, being configured to the solution of 500mg/L and 1000mg/L, drag reducing efficiency all can reach more than 60%；When lower ground layer temperature (more than 60 DEG C), this polymer can carry out from degraded, to the injury on stratum less than 10%.

Additionally, the preparation method of acrylamide based copolymer provided by the invention (solution polymerization process and reversed emulsion polymerization) has simplicity and the high advantage of monomer conversion.

Other features and advantages of the present invention will be described in detail in detailed description of the invention part subsequently.

Detailed description of the invention

Hereinafter the specific embodiment of the present invention is described in detail.It should be appreciated that detailed description of the invention described herein is merely to illustrate and explains the present invention, it is not limited to the present invention.

(1) acrylamide based copolymer

The present invention provides a kind of acrylamide based copolymer, wherein, described acrylamide based copolymer contains construction unit A, construction unit B, construction unit C and construction unit D, wherein, described construction unit A is the construction unit shown in formula (1), described construction unit B is the construction unit shown in formula (2), and described construction unit C is the construction unit shown in formula (3), and described construction unit D is the construction unit shown in formula (4)；And with the total mole number of construction unit in described acrylamide based copolymer for benchmark, the content of described construction unit A can be 5-95 mole of %, it is preferred to 10-70 mole of %, more preferably 50-70 mole of %；The content of described construction unit B is 2.5-90 mole of %, it is preferred to 5-60 mole of %, more preferably 20-40 mole of %；The content of described construction unit C is 0.5-90 mole of %, it is preferred to 5-30 mole of %, more preferably 5-20 mole of %, and the content of described construction unit D is 0.0001-1 mole of %, it is preferred to 0.001-0.5 mole of %, more preferably 0.005-0.2 mole of %；The viscosity-average molecular weight of described acrylamide based copolymer is 5,000,000-1,500 ten thousand, it is preferred to 5,000,000-1,000 ten thousand,

Wherein, R₁、R₂、R₁₂And R₁₂' it is each independently the alkyl of H or C1-C4, it is preferable that in situation, R₁And R₂It is each independently H or methyl, R₁₂And R₁₂' for methyl；R₃Straight or branched alkylidene for C1-C4, it is preferred to ethylidene (e.g. ,-CH₂CH₂-)；R₄、R₅、R₆、R₁₀、R₁₁、R₁₃、R₁₄、R₁₃' and R₁₄' it is each independently the alkyl of C1-C4, it is preferred to methyl；R₇Alkyl for H or C1-C2, it is preferred to H or methyl；R₈For oxygen atom or-NH-；R₉Straight or branched alkylidene for C1-C10；X^-For Cl^-, Br^-, I^-, SCN^-,It is preferably Cl^-。

In the present invention, the example of the alkyl of described C1-C4 can include but not limited to: methyl, ethyl, n-pro-pyl, isopropyl, normal-butyl, sec-butyl, isobutyl group and the tert-butyl group.

Described alkylidene refer to alkane lose two hydrogen atoms after residue, said two hydrogen atom can be two hydrogen atoms on same carbon atom, it is also possible to two hydrogen atoms on different carbon atoms, it can be straight chain, can also be side chain, for instance, described ethylidene can be-CH₂CH₂-or-CH (CH₃)-。

In the present invention, described alkylidene can be straight chain, it is also possible to be side chain.The example of the straight or branched alkylidene of described C1-C4 can include but not limited to: methylene, ethylidene, sub-n-pro-pyl, isopropylidene, sub-normal-butyl, sub-sec-butyl, isobutylidene, the sub-tert-butyl group.

The present inventor finds under study for action, and the acrylamide quadripolymer being made up of with construction unit D specific construction unit A, construction unit B, construction unit C can obtain fabulous resistance reducing effect.For instance, it is preferred that work as R₁And R₂It is each independently H or methyl, R₃For ethylidene (-CH₂CH₂-), R₄、R₅、R₆、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₂’、R₁₃' and R₁₄' it is each independently methyl；X^-For Cl^-.That is, described construction unit A is the construction unit shown in formula (1), wherein, and R₁For H or methyl, described construction unit B is the construction unit shown in formula (13), described construction unit C is the construction unit shown in formula (5) and/or the construction unit shown in formula (6), and described construction unit D is the construction unit shown in formula (14)

Wherein, R₂Alkyl for H or C1-C4, it is preferable that in situation, R₂For H or methyl；R₃Straight or branched alkylidene for C1-C4, it is preferred to ethylidene (e.g. ,-CH₂CH₂-)；R₇Alkyl for H or C1-C2；N and p is each independently the integer of 1-10, it is preferable that in situation, and n and p is each independently the integer of 1-4.

(2) solution polymerization process

In addition, the preparation method that the present invention also provides for a kind of acrylamide based copolymer, this preparation method includes when the solution polymerization of alkene, under initiator exists, a kind of monomer mixture is made to carry out polyreaction in water, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in formula (7), described monomer F is the monomer shown in formula (8), described monomer G is the monomer shown in formula (9), described monomer H is the monomer shown in formula (10), and with the total mole number of monomer in described monomer mixture for benchmark, the content of described monomer E is 5-95 mole of %, it is preferably 10-70 mole of %, it is more preferably 50-70 mole of %；The content of described monomer F is 2.5-90 mole of %, it is preferred to 5-60 mole of %, more preferably 20-40 mole of %；The content of described monomer G is 0.5-90 mole of %, it is preferred to 5-30 mole of %, more preferably 5-20 mole of %, and the content of described monomer H is 0.0001-1 mole of %, it is preferred to 0.001-0.5 mole of %, more preferably 0.005-0.2 mole of %；After the condition of described solution polymerization makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand, it is preferred to 5,000,000-1,000 ten thousand；

According to the present invention, when described polyreaction starts, the ratio of the gross weight of the weight of described monomer mixture and water and monomer mixture is various ratio known in those skilled in the art, usually, the ratio of the gross weight of the weight of described monomer mixture and water and monomer mixture can be 0.05-0.5:1, it is preferred to 0.15-0.4:1.

According to the present invention, described initiator can be the various initiator in this area.Such as, selected from azo series initiators and oxidoreduction series initiators.In described monomer mixture, the total mole number of monomer is for benchmark, the consumption of described azo series initiators is 0-10 mole of %, the consumption of described oxidoreduction series initiators is 0-10 mole of %, and total consumption of described azo initiator and redox initiator preferably meets: the 0.0001-10 mole of % that total consumption is the total mole number of monomer in monomer mixture of described initiator.

In the present invention, it is preferable that described azo series initiators is selected from 2,2 '-azo diisobutyl amidine hydrochlorate and/or 2,2 '-azo two [2-(2-imidazoline-2-propane)-dihydrochloride].

Described oxidoreduction series initiators includes Oxidizing and Reducing Agents, preferably, the mol ratio of described oxidant and described reducing agent is 0.5-3.5:1, when meeting aforementioned proportion, the consumption of described oxidant can be 0.0001-0.01 mole of % of the total mole number of monomer in monomer mixture, it is preferred to 0.001-0.008 mole of % of the total mole number of monomer in monomer mixture；Under preferable case, described oxidant at least one in Ammonium persulfate., potassium peroxydisulfate, sodium peroxydisulfate and hydrogen peroxide, more preferably Ammonium persulfate. and/or potassium peroxydisulfate；The consumption of described reducing agent can be 0.0001-0.005 mole of % of the total mole number of monomer in monomer mixture, it is preferred to 0.001-0.004 mole of % of the total mole number of monomer in monomer mixture；Described reducing agent can be inorganic reducing agent (helping reducing agent), preferably, described inorganic reducing agent is at least one in sodium sulfite, sodium sulfite, rongalite, sodium thiosulfate, ferrous sulfate, sodium hydrosulfite, ascorbic acid and urea, more preferably sodium sulfite and/or sodium thiosulfate.

In the present invention, it is necessary to particularly pointing out ground, described monomer H simultaneously works as the effect of chain extender in the course of the polymerization process, this is because two the double bond groups that have in described monomer H may participate in polyreaction, it is similar to " bridge formation ".

It addition, the injury of acrylamide based copolymer layer over the ground provided by the invention reduces, this is likely due in this polymer have azo group, easily occurs from degradation reaction (more than 60 DEG C) at lower ground layer temperature.

According to the present invention, described solution polymerization can also carry out under various auxiliary agents exist, and described auxiliary agent can be selected from least one in chelating agen and other auxiliary agents；In described monomer mixture, the total mole number of monomer is for benchmark, the consumption of described chelating agen is 0-2 mole of %, it is preferably 0.0001-1 mole of %, more preferably 0.0001-0.05 mole of %, the consumption of other auxiliary agents described can be 0-2 mole of %, it is preferably 0.0001-1 mole of %, more preferably 0.0001-0.2 mole of %；Preferably, the consumption of described chelating agen and other auxiliary agents makes: in described monomer mixture, the total mole number of monomer is for benchmark, and the consumption of described auxiliary agent is 0.0001-4 mole of %.

According to the present invention, described chelating agen can be at least one in disodiumedetate (EDTA), diethylenetriamine pentaacetic acid, citric acid, citrate and poly-hydroxy acrylic acid, the more preferably at least one in EDTA, citrate and diethylenetriamine pentaacetic acid, described citrate can be potassium citrate, sodium citrate, calcium citrate and ammonium citrate etc..

According to the present invention, other auxiliary agents described can be at least one in carbamide, sodium formate, isopropanol and sodium hypophosphite, it is preferred to carbamide and/or sodium formate.

It was found by the inventors of the present invention that when existing concurrently with above-mentioned various initiator and auxiliary agent, solution polymerization process can obtain the acrylamide based copolymer that viscosity-average molecular weight is controlled.

According to the present invention, the condition of described solution polymerization can be the condition that this area is conventional.Such as, described solution polymerization carries out in the presence of an inert gas, and polymeric reaction condition may include that temperature is 0-50 DEG C, and the time is 1-24 hour, and pH value is 5-13；Under preferable case, temperature is 4-45 DEG C, and the time is 4-24 hour, and pH value is 5-9.Described pH value can be adjusted by addition acid or alkali, and described acid is preferably mineral acid, and described mineral acid is preferably at least one in hydrochloric acid, sulphuric acid, sulfonic acid, nitric acid and phosphoric acid；Described alkali can be inorganic base or organic amine compound, for instance can be selected from least one in sodium hydroxide, potassium hydroxide, ammonia, methylamine, ethamine, ethanolamine and triethanolamine, it is preferred to sodium hydroxide.

The present inventor finds under study for action, take following condition can improve the molecular weight of polymer further: namely, preferably, the process of described solution polymerization includes the three phases being sequentially carried out: the reaction condition of first stage includes: temperature is 0-10 DEG C, it is preferably 4-10 DEG C, time is 1-15 hour, it is preferred to 3-10 hour；The reaction condition of second stage includes: temperature is 15-30 DEG C, it is preferred to 20-30 DEG C, and the time is 3-8 hour, it is preferred to 3-5 hour；The reaction condition of phase III includes: temperature is 35-50 DEG C, it is preferred to 35-45 DEG C, and the time is 2-14 hour, it is preferred to 2-12 hour.

Additionally, the present inventor finds under study for action, when selecting specific monomer E, monomer F, monomer G and monomer H to react, it is possible to improve the resistance reducing effect of the polymer of gained further.For instance, it is preferred that work as R₁And R₂It is each independently H or methyl, R₃For ethylidene (-CH₂CH₂-), R₄、R₅、R₆、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₂’、R₁₃' and R₁₄' it is each independently methyl；X^-For Cl^-.That is, described monomer E is the monomer shown in formula (7), wherein, and R₁For H or methyl, described monomer F is the monomer shown in formula (13), and described monomer G is the monomer shown in formula (11) and/or the monomer shown in formula (12), and described monomer H is the monomer shown in formula (14),

Wherein, there is the monomer of structure shown in formula (11) to pass through with acryloyl chloride (or methacrylic chloride) and there is the amine of structure shown in formula A be obtained by reacting under methanol solution and alkali condition.There is the monomer of structure shown in formula (12) acrylic acid methyl ester. (or methyl methacrylate) to be passed through and there is alkanolamine ester exchange reaction under the existence of catalyst (isopropyl titanate etc.) and polymerization inhibitor (phenothiazine etc.) of structure shown in Formula B obtain (referring to " isopropyl titanate catalytic transesterification synthesizing dimethylaminoethyl methacrylate ", Zhang Guangxu etc., petrochemical industry, 2008,27 (11): 1160-1165).

(3) reversed emulsion polymerization

In addition, the preparation method that the present invention also provides for a kind of acrylamide based copolymer, this preparation method includes aqueous phase and oil phase are mixed to form reversed-phase emulsion, then when emulsion polymerization, under the existence of initiator, this reversed-phase emulsion is carried out polyreaction, described aqueous phase is the aqueous solution containing monomer mixture, described oil phase contains organic solvent and emulsifying agent, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in above-mentioned formula (5), described monomer F is the monomer shown in above-mentioned formula (6), described monomer G is the monomer shown in above-mentioned formula (7), described monomer H is the monomer shown in above-mentioned formula (8), and with the total mole number of monomer in described monomer mixture for benchmark, the content of described monomer E is 5-95 mole of %, it is preferably 10-70 mole of %, it is more preferably 50-70 mole of %；The content of described monomer F is 2.5-90 mole of %, it is preferred to 5-60 mole of %, more preferably 20-40 mole of %；The content of described monomer G is 0.5-90 mole of %, it is preferred to 5-30 mole of %, more preferably 5-20 mole of %, and the content of described monomer H is 0.0001-1 mole of %, it is preferred to 0.001-0.5 mole of %, more preferably 0.005-0.2 mole of %；After the condition of described polyreaction makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand, it is preferred to 5,000,000-1,000 ten thousand；The selection of monomer shown in formula (5)-Shi (8), with described above identical, does not repeat them here.

According to the present invention, described aqueous phase is the aqueous solution containing monomer mixture.The weight of described monomer mixture and the selection of water and the ratio of the gross weight of monomer mixture, with described above identical, do not repeat herein.

According to the present invention, the part by weight of described aqueous phase and oil phase is had no particular limits, as long as making described aqueous phase and oil phase be thoroughly mixed to form reversed-phase emulsion, it is preferable that in situation, the part by weight of described aqueous phase and oil phase is 1:0.1-2, more preferably 1:0.3-0.8.

According to the present invention, described organic solvent can be various mutual exclusive with the water nonpolar or organic solvent that polarity is little for emulsion polymerization in this area, it can be such as at least one in toluene, dimethylbenzene, hexane, hexamethylene, normal heptane, isomery paraffin, isoparaffin, gasoline, kerosene and white oil, under preferable case, described organic solvent is at least one in toluene, dimethylbenzene, normal heptane, isoparaffin, hexamethylene and kerosene.

According to the present invention, described oil phase contains organic solvent and emulsifying agent.The not special requirement of consumption to described organic solvent, can change in wider scope, as long as described organic solvent and emulsifying agent are mixed to form oil phase, under preferable case, with the gross weight of described emulsion for benchmark, the consumption of described organic solvent can be 10-60 weight %, more preferably 20-35 weight %.

According to the present invention, described emulsifying agent can be the various nonionic emulsifier for emulsion polymerization in this area, it can be such as sorbitan fatty acid ester, alkylphenol polyoxyethylene, isomeric alcohol polyethenoxy ether, polyoxyethylene lauryl ether, methyl glycol fatty acid ester, laureth, benzylphenol oxygen polyoxyethylene ether, phenethyl phenol polyethenoxy ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester ethylene oxide adduct, benzyl dimethyl phenol polyethenoxy ether, at least one in fatty alcohol-polyoxyethylene ether and aliphatic amine polyoxyethylene ether.Under preferable case, described emulsifying agent is selected from sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, NPE, OPEO, benzylphenol oxygen polyoxyethylene ether, phenethyl phenol polyethenoxy ether, isomerous tridecanol polyoxyethylene ether, at least one in polyoxyethylene lauryl ether and benzyl dimethyl phenol polyethenoxy ether, it is preferred that be the compound emulsifying agent that hydrophile-lipophile balance value is 5-9 being made up of above two or two or more emulsifying agents, can be such as sorbitan fatty acid ester and NPE.

According to the present invention, the consumption of described emulsifying agent is not particularly limited, can change in wider scope, as long as described emulsifying agent and described organic solvent are mixed to form oil phase, under preferable case, with the gross weight of described emulsion for benchmark, the consumption of described emulsifying agent can be 1-15 weight %, more preferably 2-10 weight %.

According to the present invention, described initiator can be various initiators in this area, and the selection of described initiator, with described above identical, repeats no more herein.

In the present invention, it is preferable that in situation, first azo series initiators can be added aqueous phase, then be mixed to form reversed-phase emulsion with oil phase, then reversed-phase emulsion be contacted with oxidoreduction series initiators, by redox initiator initiated polymerization.

According to the present invention, described polyreaction can also carry out under various auxiliary agents exist, and described auxiliary agent can be selected from least one in chelating agen and other auxiliary agents, and the selection of described auxiliary agent, with described above identical, repeats no more herein.

According in the present invention, not special requirement on reinforced opportunity to described chelating agen, as long as making chelating agen and metal ion generation chelation so that copolymer is played static stabilization, can select to add at aqueous phase or add in oil phase, under preferable case, in order to make chelating agen play stably more fully effect, it is possible to select to add chelating agen in aqueous phase.

According to the present invention, the selection of described chelating agen, with described above identical, repeats no more herein.

Equally, it was found by the inventors of the present invention that when existing concurrently with above-mentioned various initiator and auxiliary agent, reversed emulsion polymerization can obtain the acrylamide based copolymer that viscosity-average molecular weight is controlled and dissolution velocity is fast.

According to the present invention, the condition of described emulsion polymerization can be the condition that this area is conventional.The selection of described polymeric reaction condition, with described above identical, repeats no more herein.

Equally, the present inventor finds under study for action, take following condition can improve the molecular weight of polymer further: namely, preferably, the process of described emulsion polymerization includes two stages being sequentially carried out: the reaction condition of first stage includes: temperature is 0-20 DEG C, being preferably 5-10 DEG C, the time is 1-15 hour, it is preferred to 1-5 hour；The reaction condition of second stage includes: temperature is 20-50 DEG C, it is preferred to 25-45 DEG C, and the time is 3-8 hour, it is preferred to 2-5 hour.

According to the present invention, described polyreaction products therefrom is contacted after being additionally included in described polyreaction by the method with phase inversion agent, so that described polyreaction products therefrom quickly dissolves in fracturing fluid is applied in water.Described phase inversion agent can for this area various phase inversion agent for emulsion polymerization, as long as the water solublity making described polyreaction products therefrom increases, it can be such as polyoxyethylene sorbitan fatty acid ester, NPE, OPEO, Ben-zylphenol Polyoxyethyl Ether, phenethyl phenol polyethenoxy ether, isomery ten polyoxyethylenated alcohol, isomery undecyl alcohol polyoxyethylene ether, at least one in the nonionic emulsifier of isomerous tridecanol polyoxyethylene ether and aliphatic amine polyoxyethylene ether, under preferable case, described phase inversion agent is selected from polyoxyethylene sorbitan fatty acid ester, isomery ten polyoxyethylenated alcohol, isomery undecyl alcohol polyoxyethylene ether, isomerous tridecanol polyoxyethylene ether, at least one in NPE and OPEO.

According to the present invention, the not special requirement of consumption to described phase inversion agent, as long as described polyreaction products therefrom can be made quickly to dissolve in water in fracturing fluid is applied, the consumption of described phase inversion agent makes: with the gross weight of described emulsion for benchmark, the consumption of described phase inversion agent can be 0.5-10 weight %, it is preferred to 1-4 weight %.

Additionally, the present inventor finds under study for action, when selecting specific monomer E, monomer F, monomer G and monomer H to react, it is possible to improve the resistance reducing effect of the polymer of gained further.For instance, it is preferred that work as R₁And R₂It is each independently H or methyl, R₃For ethylidene (e.g. ,-CH₂CH₂-), R₄、R₅、R₆、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₂’、R₁₃' and R₁₄' it is each independently methyl；X^-For Cl^-.That is, described monomer E is the monomer shown in formula (7), wherein, and R₁For H or methyl, described monomer F is the monomer shown in formula (13), described monomer G is the monomer shown in formula (11) and/or the monomer shown in formula (12), described monomer H is the monomer shown in formula (14), the selection of monomer shown in formula (7), formula (11)-Shi (14), with described above identical, does not repeat them here.

Additionally, present invention also offers the application in drag reducer of the described acrylamide based copolymer.Adopt described acrylamide based copolymer provided by the invention as fracturing fluid drag reducer, it is possible to obtain high and stable drag reducing efficiency, the technology that concrete application process is well known to those skilled in the art.

Hereinafter will be described the present invention by embodiment.It should be appreciated that detailed description of the invention described herein is merely to illustrate and explains the present invention, it is not limited to the present invention.

Intrinsic viscosity is measured according to GB12005.1-89 polyacrylamide For Intrinsic Viscosity Measurements method；Viscosity-average molecular weight is according to formula M_v=([η]/K)^1\α, wherein K=4.5 × 10^-3, α=0.80 is calculated；Dissolution time is measured (sample quality is all by straight polymer quality in sample) by GB12500.8-89, and the powdered samples dissolution time recorded is respectively less than 20min, and samples of latex dissolution time is respectively less than 5min；The composition of molecular structure and construction unit adopt IR spectrum and¹³C-NMR measures；Water insoluble matter content is pressed SY/T5862-1993 and is measured；Indoor drag reducing efficiency is pressed SY/T6376-2008 and is measured.

Monomer M1 shown in following embodiment Chinese style (15) and the monomer M3 shown in formula (18) is purchased from Sigma-Aldrich company, and in addition, unless specifically indicated, the reagent etc. used in embodiment, comparative example and test case is commercially available product.

Embodiment 1

The present embodiment is used for illustrating that solution polymerization process provided by the invention prepares acrylamide based copolymer.

Under room temperature, by the acrylamide (AM) of 4.26g, 74.68g formula (15) shown in M1 monomer, 30.13g N-(3-dimethylamino-propyl) Methacrylamide (purchased from Sigma-Aldrich company, identical below) and the formula (16) of 1.16g shown in M2 monomer (according to embodiment in JP08217755A 1 record method prepare, identical below) method prepare, join in reaction bulb, add deionized water 624.64g, stirring makes monomer be completely dissolved, and stirs.In flask, add the EDTA aqueous solution 5.5g of 1 weight %, the 2 of 1 weight %, 2 ' azo diisobutyl amidine hydrochlorate aqueous solution 2.1g respectively, add the sodium sulfite solution 1.1g of 0.1 weight %, carbamide 0.12g, be sufficiently stirred for and make its mix homogeneously.PH to 7.5 is regulated with the sodium hydroxide solution of 10 weight %.Control system initial temperature, to 4 DEG C, after leading to nitrogen deoxygenation 30 minutes, adds 1 weight % ammonium persulfate aqueous solution 0.45g, and continues letting nitrogen in and deoxidizing 20 minutes.Reactor is airtight, be maintained at 4 DEG C, after reacting 8 hours, react 5 hours after temperature is risen to 20 DEG C, then temperature is risen to 45 DEG C and reacts 2 hours, the gum-like product that obtain is taken out, through pelletize, dry, pulverize and can receive acrylamide copolymer p 1.

P1 is carried out various mensuration, in IR spectrum, 1660cm^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N in place；1170cm^-1Occur in that M2 monomer CH₃-C-CH₃Skeletal vibration feature stretching vibration peak, 1356cm^-1And 1401cm^-1Typical methyl symmetric curvature vibration absorption peak, 1467cm occur^-1Go out peak and belong to-CH₂-、-CH₃C-H bending vibration.May determine that the copolymer molecule obtained has the structure shown in formula (17), recording its viscosity-average molecular weight Mv by viscosity method is 5,200,000, and monomer conversion is more than 99.9%.Wherein, formula (17) and x₁、x₂、y₁、y₂、z₁、z₂Only represent type and the number of construction unit with u, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:6:2.95:0.05.

Comparative example 1

Acrylamide based copolymer is prepared according to the method for embodiment 1, the difference is that, it is added without M1 monomer, N-(3-dimethylamino-propyl) Methacrylamide and M2 monomer, (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride of acrylamide Yu identical molal quantity is carried out polyreaction, thus obtaining bipolymer DP1, record its viscosity-average molecular weight M_vIt is 14,520,000.

Embodiment 2

By the acrylamide (AM) of 29.85g, the M3 monomer shown in formula (18) of 5.80g, 25.44g N-(4-dimethylaminobutyl) acrylate (purchased from Sigma-Aldrich company, identical below) and the formula (16) of 0.46g shown in M2 monomer join in polymerization bottle, add 143.62g deionized water, stirring makes monomer be completely dissolved, the EDTA aqueous solution 4.65g of 1 weight % is added respectively in flask, add 1 weight % azo diisobutyl amidine hydrochlorate aqueous solution 1.23g, add 0.1% sodium sulfite solution 1.15g, add carbamide 0.11g, it is sufficiently stirred for and makes its mix homogeneously.PH to 7.1 is regulated with the sodium hydroxide solution of 10 weight %.Control system initial temperature, to 10 DEG C, after leading to nitrogen deoxygenation 30 minutes, adds 1 weight % ammonium persulfate aqueous solution 1.0g, and continues letting nitrogen in and deoxidizing 10 minutes.Reactor is airtight, be maintained at 10 DEG C, after reacting 3 hours, be warming up to 30 DEG C, after reacting 3 hours, be warming up to 35 DEG C and react 12 hours, the gum-like product that obtain is taken out, through pelletize, dry, pulverize and can receive acrylamide copolymer p 2.

P2 is carried out various mensuration, 1660cm in IR spectrum^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N, 1170cm in place^-1Occur in that M2 monomer CH₃-C-CH₃The feature stretching vibration peak of skeletal vibration, 1356cm^-1And 1401cm^-1Typical methyl symmetric curvature vibration absorption peak occurs, 2923,2852cm^-1Place goes out peak and is respectively belonging to-CH₂-、-CH₃C-H stretching vibration.May determine that the copolymer molecule obtained has the structure shown in formula (19), recording its viscosity-average molecular weight Mv by viscosity method is 7,230,000, and monomer conversion is more than 99.9%.Wherein, formula (19) and x₁、x₂、y₁、y₂、z₁、z₂Only represent type and the number of construction unit with u, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:0.07:0.35:0.003.

Embodiment 3

Under room temperature, by the Methacrylamide of 25.53g, 51.07g the M3 monomer shown in formula (18), N-(the 5-dimethylamino amyl group) Methacrylamide of 7.13g is (purchased from Sigma-Aldrich company, identical below) and the formula (16) of 0.002g shown in M2 monomer in polymerization bottle, add 125.55g deionized water, stirring makes monomer be completely dissolved, the EDTA aqueous solution 11.63g of 1 weight % is added respectively in flask, add 1 weight % azo diisobutyl amidine hydrochlorate aqueous solution 2.13g, add 0.1 weight % sodium sulfite solution 1.13g, add carbamide 0.20g, it is sufficiently stirred for and makes its mix homogeneously.PH to 7.3 is regulated with the sodium hydroxide solution of 10 weight %.Control system initial temperature, to 8 DEG C, after leading to nitrogen deoxygenation 30 minutes, adds 1% ammonium persulfate aqueous solution 0.4g, and continues letting nitrogen in and deoxidizing 10 minutes.Reactor is airtight, be maintained at 8 DEG C, after reacting 10 hours, be warming up to 25 DEG C, after reacting 4 hours, be warming up to 40 DEG C and react 7 hours, the gum-like product that obtain is taken out, through pelletize, dry, pulverize and can receive acrylamide copolymer p 3.

P3 is carried out various mensuration, 1660cm in IR spectrum^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N in place；1170cm^-1Occur in that M2 monomer CH₃-C-CH₃The feature stretching vibration peak of skeletal vibration, it may be determined that the copolymer molecule obtained has the structure shown in formula (20), recording its viscosity-average molecular weight Mv by viscosity method is 6,500,000, and monomer conversion is more than 99.9%.Wherein, formula (20) and x₁、x₂、y₁、y₂、z₁、z₂Only represent type and the number of construction unit with u, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and x₁、x₂、y₁、y₂、z₁、z₂、u₁And u₂Numerical value respectively (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:0.88:0.12:0.00002.

Embodiment 4

The present embodiment is used for illustrating that reversed emulsion polymerization provided by the invention prepares acrylamide based copolymer.

(1) by the Methacrylamide of 5.11g, 74.68g the M1 monomer shown in formula (15), 30.13g N-(3-dimethylamino-propyl) Methacrylamide and the M2 monomer shown in formula (16) of 1.16g join in configuration bottle, add 181.24g deionized water, stirring makes monomer be completely dissolved, the EDTA aqueous solution 14.61g of 1 weight % is added respectively in flask, add 1 weight % azo diisobutyl amidine hydrochlorate aqueous solution 1.03g, add carbamide 0.15g, it is sufficiently stirred for and makes its mix homogeneously, pH to 7.1 is regulated with the sodium hydroxide solution of 10 weight %, obtain aqueous phase.

(2) by sorbitan fatty acid ester (span60, Sigma-Aldrich company, identical below) 42.38g, alkylphenol polyoxyethylene (IgepalCA720, Sigma-Aldrich company, identical below) 10g, 194.11g kerosene is mixed into oil phase, and the aqueous phase obtained in step (1) is joined in whole oil phase, form reversed-phase emulsion by mixing at a high speed and join in reactor.

(3) control system initial temperature 5 DEG C, after leading to nitrogen deoxygenation 30 minutes, add 1 weight % aqueous solution of sodium bisulfite 0.25g, add 1 weight % ammonium persulfate aqueous solution 1.0g and continue letting nitrogen in and deoxidizing 10 minutes.Reactor is airtight, it is maintained at 5 DEG C, after reacting 5 hours, is warming up to 45 DEG C, react 2 hours.After question response temperature is cooled to room temperature, adds 22.18g NPE (Sigma-Aldrich company, identical below), obtain emulsion-formulated products with 80 order filter-cloth filterings.After reversed-phase emulsion product acetone and methanol mixed solvent being precipitated out, acrylamide copolymer p 4 can be obtained.

P4 is carried out various mensuration, 1660cm in IR spectrum^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N, 1170cm in place^-1Occur in that M2 monomer CH₃-C-CH₃The feature stretching vibration peak of skeletal vibration, 1356cm^-1And 1401cm^-1Typical methyl symmetric curvature vibration absorption peak, 1467cm occur^-1Go out peak and belong to-CH₂-、-CH₃C-H bending vibration.May determine that the copolymer molecule obtained has the structure shown in formula (21), recording its viscosity-average molecular weight Mv by viscosity method is 5,700,000, and monomer conversion is more than 99.9%.Wherein, formula (21) and x₁、x₂、y₁、y₂、z₁、z₂、u₁And u₂Only represent type and the number of construction unit, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:6:2.95:0.05.

Comparative example 2

Acrylamide based copolymer is prepared according to the method for embodiment 4, the difference is that, it is added without M1 monomer, N-(3-dimethylamino-propyl) Methacrylamide and M2 monomer, (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride of Methacrylamide Yu identical molal quantity is carried out polyreaction, thus obtaining bipolymer DP2, record its viscosity-average molecular weight M_vIt is 9,450,000.

Embodiment 5

(1) by the Methacrylamide of 35.74g, the M3 monomer shown in formula (18) of 5.80g, 25.44g N-(4-dimethylaminobutyl) acrylate and the M2 monomer shown in formula (16) of 0.46g join in preparation bottle, add 269.76g deionized water, stirring makes monomer be completely dissolved, the EDTA aqueous solution 7.83g of 1 weight % is added respectively in flask, add 1 weight % azo diisobutyl amidine hydrochlorate aqueous solution 2.03g, add carbamide 0.10g, it is sufficiently stirred for and makes its mix homogeneously, with the sodium hydroxide solution pH regulator of 15 weight % to 7.0, obtain aqueous phase.

(2) by sorbitan fatty acid ester (span60) 40g, alkylphenol polyoxyethylene (IgepalCA720) 3.39g, 130.19g kerosene is mixed into oil phase, and the aqueous phase obtained in step (1) is all joined in oil phase, form reversed-phase emulsion by mixing at a high speed and join in reactor.

(3) control system initial temperature 10 DEG C, after leading to nitrogen deoxygenation 30 minutes, add 1 weight % aqueous solution of sodium bisulfite 0.13g, add 1 weight % ammonium persulfate aqueous solution 0.63g, and continue letting nitrogen in and deoxidizing 10 minutes.Reactor is airtight, it is maintained at 10 DEG C, after reacting 1 hour, is warming up to 25 DEG C, react 5 hours, after question response temperature is cooled to room temperature, adds 10.41g NPE, obtain emulsion-formulated products with 80 order filter-cloth filterings.After reversed-phase emulsion product acetone and methanol mixed solvent being precipitated out, acrylamide copolymer p 5 can be obtained.

P5 is carried out various mensuration, 1660cm in IR spectrum^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N, 1170cm in place^-1Occur in that M2 monomer CH₃-C-CH₃The feature stretching vibration peak of skeletal vibration, 1467cm^-1Go out peak and belong to-CH₂-、-CH₃C-H bending vibration, 1356cm^-1And 1401cm^-1Typical methyl symmetric curvature vibration absorption peak occurs.May determine that the copolymer molecule obtained has the structure shown in formula (22), recording its viscosity-average molecular weight Mv by viscosity method is 8,050,000, and monomer conversion is more than 99.9%.Wherein, formula (22) and x₁、x₂、y₁、y₂、z₁、z₂Only represent type and the number of construction unit with u, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:0.07:0.35:0.003.

Embodiment 6

(1) by the acrylamide of 21.32g, 51.07g the M3 monomer shown in formula (18), N-(the 5-dimethylamino amyl group) Methacrylamide of 7.13g and the M2 monomer shown in formula (16) of 0.002g join in preparation bottle, add 450.63g deionized water, stirring makes monomer be completely dissolved, the EDTA aqueous solution 8.5g of 1 weight % is added respectively in flask, add 1 weight % azo diisobutyl amidine hydrochlorate aqueous solution 2.1g, add carbamide 0.08g, it is sufficiently stirred for and makes its mix homogeneously, pH to 7.1 is regulated with the sodium hydroxide solution of 10 weight %, obtain aqueous phase.

(2) by sorbitan fatty acid ester (span60) 10g, alkylphenol polyoxyethylene (IgepalCA720, Sigma-Aldrich company, identical below) 11.63g, 162.25g kerosene is mixed into oil phase, and join in oil phase by step (1) obtains aqueous phase, form reversed-phase emulsion by mixing at a high speed and join in reactor.

(3) control system initial temperature 8 DEG C, after leading to nitrogen deoxygenation 30 minutes, add 1 weight % aqueous solution of sodium bisulfite 0.18g, add 1 weight % ammonium persulfate aqueous solution 1.3g, and continue letting nitrogen in and deoxidizing 10 minutes.Reactor is airtight, it is maintained at 8 DEG C, after reacting 3 hours, is warming up to 40 DEG C, react 4 hours, after question response temperature is cooled to room temperature, adds 7.03g NPE, obtain emulsion-formulated products with 100 order filter-cloth filterings.After reversed-phase emulsion product acetone and methanol mixed solvent being precipitated out, acrylamide copolymer p 6 can be obtained.

P6 is carried out various mensuration, in IR spectrum, 1660cm^-1And 1635cm^-1Place occurs belonging to amide Ⅰ absworption peak (C=O stretching vibration) and the amide II band absworption peak (N-H bending vibration) of amide groups respectively, at 1430cm^-1There is the stretching vibration absworption peak of C-N, 1170cm in place^-1Occur in that M2 monomer CH₃-C-CH₃The feature stretching vibration peak of skeletal vibration, 1356cm^-1And 1401cm^-1Typical methyl symmetric curvature vibration absorption peak, 1467cm occur^-1Go out peak and belong to-CH₂-、-CH₃C-H bending vibration.May determine that the copolymer molecule obtained has the structure shown in formula (23), recording its viscosity-average molecular weight Mv by viscosity method is 7,100,000, and monomer conversion is more than 99.9%.Wherein, formula (23) and x₁、x₂、y₁、y₂、z₁、z₂Only represent type and the number of construction unit with u, and do not indicate that the connected mode of construction unit.X₁、x₂、y₁、y₂、z₁、z₂Determining by inventory with the concrete numerical value of u, the composition of molecular structural formula and construction unit adopts quantitatively¹³C composes mensuration, wherein, and (x₁+x₂): (y₁+y₂): (z₁+z₂): u=1:0.88:0.12:0.00002.

Test case 1

Water-insoluble is to measure according to the method for regulation in SY/T5862-1993.By P1-P6, DP1, DP2 and hydroxypropyl guar gum (JXY wellfracturing hydroxypropyl melon rubber powder, Shandong Juxin Chemical Co., Ltd., identical below) carry out water solublity mensuration, result is as shown in table 1.

Table 1

As can be seen from Table 1, in acrylamide copolymer p 1-P6 prepared by two kinds of methods provided by the invention, water insoluble matter content is significantly lower than commonly using the hydroxypropyl guar gum cooking drag reducer in site operation, this illustrates and hydroxypropyl guar gum ratio, uses P1-P6 as shale gas pressure break drag reducer, the injury on stratum is low.

Test case 2

Under 2500rpm shear rate, respectively by P1-P6, DP1, DP2, partially hydrolyzed polyacrylamide (PHPA) (HPAM, Zibo Tian Jian Chemical Co., Ltd., trade mark TJY-1, viscosity-average molecular weight is 1000-1300 ten thousand, lower same) and each it is slowly added in water/alcoholic solution (using methanol in this test case) that volume ratio is 80/20 and 60/40 respectively, the consumption of P1-P6, DP1, DP2 and partially hydrolyzed polyacrylamide (PHPA) is the 0.01 weight % (sample quality is by straight polymer quality in sample) of water/alcoholic solution, dissolution time is 30min, and result is as shown in table 2.

Table 2

From Table 2, it can be seen that acrylamide copolymer p 1-P6 prepared by two kinds of methods provided by the invention is as shale gas pressure break drag reducer, compared with partially hydrolyzed polyacrylamide (PHPA), good with the compatibility of alcohol.

Test case 3

When temperature is 25 DEG C, by P1-P6, DP1, DP2, HPAM and hydroxypropyl guar gum are dissolved in pure water respectively and concentration is 2 weight %, 4 weight %, 8 weight %, 10 weight %, in NaCl or the KCl solution of 12 weight %, the solution (sample quality is by straight polymer quality in sample) of 500mg/L and the 1000mg/L being configured to, then on GLM-1 pipeline frictional resistance determinator, the drag reducing efficiency of above-mentioned solution is measured according to the method for regulation in SY/T6376-2008, (test condition: the internal diameter of test section pipeline is 8mm, the length of test section pipeline is 9m, infusion discharge capacity is 30L/min), result is as shown in Table 3 and Table 4.

Table 3

Table 4

Can be seen that from table 3 and table 4, acrylamide copolymer p 1-P6 prepared by two kinds of methods provided by the invention is as shale gas pressure break drag reducer, compared with hydroxypropyl guar gum, HPAM, DP1 and DP2, with clay stabilizer (as, KCl and NaCl) compatibility is good, and anti-salt property is excellent.

Test case 4

Matrix permeability of rock core is damaged experiment by fracturing fluid filtrate in oil and gas industry standard SY/T5107-2005 " aqueous fracturing fluid method of evaluating performance " by the nocuity of rock core by friction reducer to be carried out, testing in American core company formation injury tester device (FDS-800), the matrix permeability of rock core is 2md.

P1-P6, DP1 and DP2 are dissolved in respectively pure water, it is configured to the solution (sample quality is by straight polymer quality in sample) of 1000mg/L, 24hr is preserved testing when temperature is 65 DEG C, at American core company formation damage test system (FDS-800) its nocuity to rock core of upper test, result is as shown in table 5.

Table 5

As can be seen from Table 5, acrylamide copolymer p 1-P6 prepared by two kinds of methods provided by the invention to the injury of rock core significantly lower than in site operation the conventional comparative sample cooking drag reducer, this illustrates to use P1-P6 as shale gas pressure break drag reducer, the injury on stratum is low.

Above-mentioned test result illustrates, the acrylamide based copolymer provided by the invention insolubles content in water is only 0.01%；Under the shear rate of 2500rpm, can be dissolved completely in water/alcoholic solution, good with the compatibility of alcohol, owing to the compatibility with alcohol and clay stabilizer (NaCl or KCl) improves, improve anti-filtration property, and still there is when high salt and high shear high drag reducing efficiency；When lower ground layer temperature (more than 60 DEG C), there is self-degradation, the injury on stratum is low.Additionally, the preparation method of acrylamide based copolymer provided by the invention has simplicity and the high advantage of monomer conversion.

The preferred embodiment of the present invention described in detail above; but, the present invention is not limited to the detail in above-mentioned embodiment, in the technology concept of the present invention; technical scheme can being carried out multiple simple variant, these simple variant belong to protection scope of the present invention.

It is further to note that each the concrete technical characteristic described in above-mentioned detailed description of the invention, in reconcilable situation, it is possible to be combined by any suitable mode.In order to avoid unnecessary repetition, various possible compound modes are no longer illustrated by the present invention separately.

Additionally, can also carry out combination in any between the various different embodiment of the present invention, as long as it is without prejudice to the thought of the present invention, it should be considered as content disclosed in this invention equally.

Claims

1. an acrylamide based copolymer, it is characterized in that, described acrylamide based copolymer contains construction unit A, construction unit B, construction unit C and construction unit D, wherein, described construction unit A is the construction unit shown in formula (1), described construction unit B is the construction unit shown in formula (2), and described construction unit C is the construction unit shown in formula (3), and described construction unit D is the construction unit shown in formula (4)；And with the total mole number of construction unit in described acrylamide based copolymer for benchmark, the content of described construction unit A is 5-95 mole of %, the content of described construction unit B is 2.5-90 mole of %, the content of described construction unit C is 0.5-90 mole of %, and the content of described construction unit D is 0.0001-1 mole of %；The viscosity-average molecular weight of described acrylamide based copolymer is 5,000,000-1,500 ten thousand；

Wherein, R₁、R₂、R₁₂And R₁₂' it is each independently the alkyl of H or C1-C4；R₃Straight or branched alkylidene for C1-C4；R₄、R₅、R₆、R₁₀、R₁₁、R₁₃、R₁₄、R₁₃' and R₁₄' it is each independently the alkyl of C1-C4；R₇Alkyl for H or C1-C2；R₈For oxygen atom or-NH-；R₉Straight or branched alkylidene for C1-C10；X^-For Cl^-、Br^-、I^-、SCN^-、

2. acrylamide based copolymer according to claim 1, wherein, in described acrylamide based copolymer, the total mole number of construction unit is for benchmark, the content of described construction unit A is 10-70 mole of %, the content of described construction unit B is 5-60 mole of %, the content of described construction unit C is 5-30 mole of %, and the content of described construction unit D is 0.001-0.5 mole of %, and the viscosity-average molecular weight of described acrylamide based copolymer is 5,000,000-1,000 ten thousand.

3. acrylamide based copolymer according to claim 1, wherein, R₁And R₂It is each independently H or methyl, R₃For ethylidene, R₄、R₅、R₆、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₂’、R₁₃' and R₁₄' it is each independently methyl；X^-For Cl^-。

4. acrylamide based copolymer according to claim 1, wherein, described construction unit C is the construction unit shown in formula (5) and/or the construction unit shown in formula (6),

Wherein, R₇Alkyl for H or C1-C2；N and p is each independently the integer of 1-10.

5. the preparation method of an acrylamide based copolymer, this preparation method includes when the solution polymerization of alkene, under initiator exists, a kind of monomer mixture is made to carry out polyreaction in water, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in formula (7), described monomer F is the monomer shown in formula (8), described monomer G is the monomer shown in formula (9), described monomer H is the monomer shown in formula (10), in described monomer mixture, the total mole number of monomer is for benchmark, the content of described monomer E is 5-95 mole of %, the content of described monomer F is 2.5-90 mole of %, the content of described monomer G is 0.5-90 mole of %, the content of described monomer H is 0.0001-1 mole of %；After the condition of described solution polymerization makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand,

6. the preparation method of an acrylamide based copolymer, this preparation method includes aqueous phase and oil phase are mixed to form reversed-phase emulsion, then when emulsion polymerization, under the existence of initiator, this reversed-phase emulsion is carried out polyreaction, described aqueous phase is the aqueous solution containing monomer mixture, described oil phase contains organic solvent and emulsifying agent, wherein, described monomer mixture contains monomer E, monomer F, monomer G and monomer H, described monomer E is the monomer shown in formula (7), described monomer F is the monomer shown in formula (8), described monomer G is the monomer shown in formula (9), described monomer H is the monomer shown in formula (10), in described monomer mixture, the total mole number of monomer is for benchmark, the content of described monomer E is 5-95 mole of %, the content of described monomer F is 2.5-90 mole of %, the content of described monomer G is 0.5-90 mole of %, the content of described monomer H is 0.0001-1 mole of %；After the condition of described emulsion polymerization makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,500 ten thousand,

7. preparation method according to claim 6, wherein, the weight ratio of described aqueous phase and oil phase is 1:0.1-2.

8. preparation method according to claim 7, wherein, the weight ratio of described aqueous phase and oil phase is 1:0.3-0.8.

9. preparation method according to claim 6, wherein, with the gross weight of described emulsion for benchmark, the consumption of described organic solvent is 10-60 weight %, and the consumption of described emulsifying agent is 1-15 weight %.

10. preparation method according to claim 9, wherein, with the gross weight of described emulsion for benchmark, the consumption of described organic solvent is 20-35 weight %, and the consumption of described emulsifying agent is 2-10 weight %.

11. preparation method according to claim 6, wherein, described polyreaction products therefrom is contacted after being additionally included in described polyreaction by the method with phase inversion agent.

12. preparation method according to claim 11, wherein, with the gross weight of described emulsion for benchmark, the consumption of described phase inversion agent is 0.5-10 weight %.

13. preparation method according to claim 12, wherein, with the gross weight of described emulsion for benchmark, the consumption of described phase inversion agent is 1-4 weight %.

14. the preparation method according to claim 5 or 6, wherein, in described monomer mixture, the total mole number of monomer is for benchmark, the content of described monomer E is 10-70 mole of %, the content of described monomer F is 5-60 mole of %, the content of described monomer G is 5-30 mole of %, and the content of described monomer H is 0.001-0.5 mole of %；After the condition of described polyreaction makes polyreaction, the viscosity-average molecular weight of resulting polymers is 5,000,000-1,000 ten thousand.

15. the preparation method according to claim 5 or 6, wherein, R₁And R₂It is each independently H or methyl, R₃For ethylidene, R₄、R₅、R₆、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₂’、R₁₃' and R₁₄' it is each independently methyl；X^-For Cl^-。

16. the preparation method according to claim 5 or 6, wherein, described monomer G is the monomer shown in formula (11) and/or the monomer shown in formula (12),

17. the preparation method according to claim 5 or 6, wherein, the ratio of the gross weight of the weight of described monomer mixture and water and monomer mixture is 0.05-0.5:1.

18. the preparation method according to claim 5 or 6, wherein, the ratio of the gross weight of the weight of described monomer mixture and water and monomer mixture is 0.15-0.4:1.

19. the preparation method according to claim 5 or 6, wherein, described initiator is selected from azo series initiators and oxidoreduction series initiators, in described monomer mixture, the total mole number of monomer is for benchmark, the consumption of described azo series initiators is 0-10 mole of %, the consumption of described oxidoreduction series initiators is 0-10 mole of %, and total consumption of described initiator is 0.0001-10 mole of %；Described azo series initiators is selected from 2,2 '-azo diisobutyl amidine hydrochlorate and/or 2,2 '-azo two [2-(2-imidazoline-2-base) propane] dihydrochloride, described oxidoreduction series initiators includes Oxidizing and Reducing Agents, the mol ratio of described oxidant and described reducing agent is 0.5-3.5:1, and described oxidant is at least one in Ammonium persulfate., potassium peroxydisulfate, sodium peroxydisulfate and hydrogen peroxide；Described reducing agent is at least one in inorganic reducing agent, rongalite, ascorbic acid and urea, and described inorganic reducing agent is at least one in sodium sulfite, sodium sulfite, sodium thiosulfate, ferrous sulfate and sodium hydrosulfite.

20. the preparation method according to claim 5 or 6, wherein, described polyreaction carries out under auxiliary agent exists, and described auxiliary agent is at least one in chelating agen and other auxiliary agents；With the total mole number of described monomer mixture for benchmark, the consumption of described chelating agen is 0-2 mole of %, the consumption of other auxiliary agents described is 0-2 mole of %, and with the total mole number of monomer in described monomer mixture for benchmark, total consumption of described auxiliary agent is 0.0001-4 mole of %；Described chelating agen is at least one in disodiumedetate, diethylenetriamine pentaacetic acid, citric acid, citrate and poly-hydroxy acrylic acid, and other auxiliary agents described are at least one in carbamide, sodium formate, isopropanol and sodium hypophosphite.

21. preparation method according to claim 5, wherein, described solution polymerization carries out in the presence of an inert gas, and polymeric reaction condition includes: temperature is 0-50 DEG C, and the time is 1-24 hour, and pH value is 5-13.

22. preparation method according to claim 6, wherein, described emulsion polymerization carries out in the presence of an inert gas, and polymeric reaction condition includes: temperature is 0-50 DEG C, and the time is 1-24 hour, and pH value is 5-13.

23. the preparation method according to claim 5 or 21, wherein, the process of described solution polymerization includes the three phases being sequentially carried out, and the reaction condition of first stage includes: temperature is 0-10 DEG C, and the time is 1-15 hour；The reaction condition of second stage includes: temperature is 15-30 DEG C, and the time is 3-8 hour；The reaction condition of phase III includes: temperature is 35-50 DEG C, and the time is 2-14 hour.

24. the preparation method according to claim 6 or 22, wherein, the process of described emulsion polymerization includes two stages being sequentially carried out, and the reaction condition of first stage includes: temperature is 0-20 DEG C, and the time is 1-15 hour；The reaction condition of second stage includes: temperature is 20-50 DEG C, and the time is 2-8 hour.

25. the acrylamide based copolymer that in claim 1-4, the acrylamide based copolymer described in any one or the method described in any one in claim 5-24 prepare is as the application of drag reducer.