CN100363394C - Water soluble amphoteric ion copolymer and preparation process thereof - Google Patents

Water soluble amphoteric ion copolymer and preparation process thereof Download PDF

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CN100363394C
CN100363394C CNB2006100209120A CN200610020912A CN100363394C CN 100363394 C CN100363394 C CN 100363394C CN B2006100209120 A CNB2006100209120 A CN B2006100209120A CN 200610020912 A CN200610020912 A CN 200610020912A CN 100363394 C CN100363394 C CN 100363394C
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water
copolymer
preparation
kerosene
amphoteric ion
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CN1861654A (en
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陈馥
徐东梅
刘彝
刘徐慧
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Southwest Petroleum University
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Abstract

The present invention relates to a water soluble amphoteric ion copolymer and a preparation method thereof. The copolymer comprises two structural units, namely 2-methyl-2-acrylamido propanesulfonic acid and methacrylatoethyl trimethyl ammonium chloride. The preparation method orderly comprises the following procedures that (1) anhydrated sorbitol monoleate as emulsifying agents and anhydrated sorbitol monostearate with 20 polyoxyethylene chains are added to kerosene in the mass ratio of 4 to 6:1 and the mass fraction accounts for 5 to 10% of the kerosene; (2) two monomers are respectively dissolved in water in the mass ratio of 6 to 9:1, the pH value of a water solution is regulated into 7, and the total mass fraction of the monomers is from 35 to 55%; (3) a kerosene phase and a water phase are mixed in the volume ratio of 1:0.5 to 2.3, nitrogen gas is introduced, redox initiators are added, a mixture is put in a constant temperature water bath and reacts for 4 to 6h, and copolymer emulsion can be prepared. The copolymer has the advantages of good viscosity increasing performance and salt resistance, simple, convenient and feasible preparation method, mild condition and easy purification, separation and use.

Description

A kind of water soluble amphoteric ion copolymer and preparation method thereof
Technical field
The present invention relates to a kind of amphoteric ion copolymer and preparation method thereof.
Background technology
Amphoteric ion polymer is a class novel high polymer chemical agent.Because of its distinctive molecular structure and excellent application performance energy, in petroleum industry, used widely in recent years, at aspects such as additive for drilling fluid, fracturing fluid additive, cementing extra-agent, chemical agent for intensified oil production certain application is arranged all, development potentiality is huge.
The unisexuality polyelectrolyte has good tackifying ability, but salt resistance is poor, the viscosity of amphiphilic polymers then rises gradually with small molecule salt release polymers molecular coil, and amphoteric ion polymer has good tackifying and salt resistance concurrently, brings into play the effect of high molecular polymer greatly.Present zwitterionic synthetic method has polymerization in homogeneous phase and heterogeneous polymerization.Polymerization in homogeneous phase mainly is solution polymerization, and heterogeneous polymerization mainly contains suspension polymerization and letex polymerization.Letex polymerization can be divided into various ways such as inverse emulsion polymerization, micro-emulsion polymerization, emulsifier-free emulsion polymerization.Though the solution polymerization system operation is simple, monomer concentration is lower, and the unit volume equipment capacity is lower, and the polymer molecule quality is little.Adopt the inverse emulsion polymerization method, it provides a polymerization process with high rate of polymerization and high molecular weight product for water-soluble monomer, its biggest advantage is exactly the solid content height of product, the polymkeric substance relative molecular mass is higher, product dissolves fast in water and dissolves evenly, be very beneficial for situ configuration, the preparation of water-soluble polymers is had very big using value.
That has reported has: and AM/ methylacryoyloxyethyl trimethyl ammonium chloride/AMPS inverse emulsion polymerization (Shen Yinghua, Xie Long, Wang Zhizhong. polymer journal, 2005, (6): 846~850); The MOTAC/AA/AM aqueous solution polymerization (Wang Zhonghua. oilfield chemistry, 1996,13 (4): 369~370), (AM/AA/DADMAC) the antiphase emulsifiable method preparation research (Zhao Yong of multipolymer plugging agent, Li Weiyun breathes out profit China etc. fine chemistry industry .1997,14 (6): 35~37); Synthetic and the performance of AMPS/HMOPTA/AM copolymer fluid loss agent (Liu Minghua, Zhou Lequn, Yang Xiaohua. Speciality Petrochemicals progress .2005,6 (3): 24~27) etc.; In recent years, the research of Chinese scholars mainly concentrates on the binary or the terpolymer of acrylamide monomers, and is less for the research of positively charged ion, anionic monomer binary copolymerization.Therefore the zwitter-ion binary polymer product innovation of development research excellent performance for water treatment, all has broad application prospects on the fields such as paper industry and petroleum drilling and mining.
Summary of the invention
The object of the present invention is to provide a kind of water soluble amphoteric ion copolymer, it is 2-methyl-2-acrylamido propanesulfonic acid/methylacryoyloxyethyl trimethyl ammonium chloride multipolymer, this multipolymer has tackifying and salt resistance preferably, can be used as tackifier and is widely used in industries such as oil production, coating, papermaking.Another object of the present invention is to provide the preparation method of this amphoteric ion copolymer, this method is simple and feasible, and mild condition is easy to purify, separates and uses.
A kind of water soluble amphoteric ion copolymer, comprise 2-methyl-2-acrylamido propanesulfonic acid (AMPS), two kinds of structural unit: AMPS of methylacryoyloxyethyl trimethyl ammonium chloride (DMC) are unsaturated polymerization monomers of a kind of multi-functional strong anionic property and water-soluble functional group, have good polymerization activity.Contain unsaturated twoly strong in the DMC molecular structure, have extremely strong polarity, contain tertiary ester groups in the molecule, can with sour salify, have acid resistance, but the reactivity ratio of cationic monomer DMC is lower, reaction can be subjected to inhibition, the dosage of cationic monomer DMC is unsuitable too high.The structural formula of this zwitter-ion copolymer AMPS/DMC is:
Figure C20061002091200041
Wherein x: y is 6~9: 1.
The synthetic method of AMPS/DMC amphoteric ion polymer may further comprise the steps:
(1). the preparation oil phase: with emulsifying agent sorbitan monooleate (Span-80) with to have 20 polyoxyethylene chain sorbitan monostearates (Tween-60) be to join in kerosene at 4~6: 1 with mass ratio, the massfraction that emulsifying agent accounts for kerosene is 5~10%;
(2). the preparation water: is 6~9 with 2-methyl-2-acrylamido propanesulfonic acid (AMPS), methylacryoyloxyethyl trimethyl ammonium chloride (DMC) with mass ratio: 1 takes by weighing, pH value soluble in water respectively and the adjusting monomer solution is 7, and monomer total mass mark is 35~55%;
(3). polyreaction: is 1: 0.5~2.3 mixing with oil phase and water with volume ratio, stirs and forms white milk sap, and logical nitrogen is regulated bath temperature at 30~55 ℃, adds water-soluble ammonium persulphate ((NH 4) 2S 2O 8)-S-WAT (Na 2SO 3) redox initiator, the initiator dosage is 0.2~0.6% of a monomer total mass, places water bath with thermostatic control stirring reaction 4~6h, gets dope, is copolymer emulsion.
Copolymer emulsion is cleaned for several times with ethanol and acetone, and the product that washes out is pink colour and has visco-elasticity, places 60 ℃ of dry 24h of baking oven, promptly makes multipolymer.
Adopt the inverse emulsion polymerization method to make the AMPS/DMC amphoteric ion copolymer.Span-80 and Tween-60 are joined in the kerosene, add the monomer solution that regulates the pH value, form emulsion, add oxidation-reduction initiator then, sealing is placed on to react in the water bath with thermostatic control and gets final product.This experiment reaction mechanism is a mechanism of free-radical polymerization, and reaction formula is as follows:
Figure C20061002091200051
Compare with existing amphoteric ion polymer and technology of preparing thereof, the present invention has following beneficial effect:
(1). in amphoteric ion polymer is synthetic, the normal acrylamide (AM) that adds, but the amphiphilic polymers solution that contains acrylamide is along with digestion time prolongs, negatively charged ion degree (degree of hydrolysis) constantly increases descends the soltion viscosity anti-salt property, and AMPS of the present invention, DMC zwitterion monomer binary copolymerization have improved anti-salt property.
(2). the polymkeric substance that adopts inverse emulsion polymerization to generate has well water-soluble, shows good tackifying in distilled water;
(3). sulfonic group is extremely insensitive to salt, makes polymkeric substance have good salt resistance, has improved the thermostability of polymkeric substance simultaneously;
In field of petroleum exploitation, along with to the intensification of viscosifying agent understanding and the expansion of gelled acid technology rig-site utilization scope, the requirement of gelling agent for acid fluid is improved constantly.Be applied to on-the-spot domestic viscosifying agent product multilist and reveal shortcomings such as being subjected to shear inference is big, weak, the on-the-spot preparation time length of acid solution tackifying ability, limited the performance of viscosifying agent effect, add that acid solution and limestone or dolomite reaction can generate the calcium chloride of high density, sodium-chlor and damage polymer stabilizing, cause acid liquid viscosity to descend or polymer precipitation, amphiphilic polymers then has fabulous anticalcium, saline-alkaline tolerance and good solubility in acid, thermostability.The amphoteric ion polymer that AMPS/DMC copolymerization therefore of the present invention generates has certain researching value.
Description of drawings
Fig. 1 is that multipolymer of the present invention is as the tackifying of gelling agent for acid fluid and the relation of multipolymer dosage
Fig. 2 is that multipolymer of the present invention is as the thermostability of gelling agent for acid fluid and the relation of temperature
Fig. 3 is the salt resistance and the relation that add inorganic salt of multipolymer of the present invention as gelling agent for acid fluid
Fig. 4 is shear stability and the time relation of multipolymer of the present invention as gelling agent for acid fluid
Fig. 5 is the infrared spectrum of AMPS/DMC amphoteric ion copolymer of the present invention
Embodiment
Synthesizing of embodiment 1 AMPS/DMC amphoteric ion polymer
Prescription-1:(1). oil phase: is to be dissolved in kerosene at 5: 1 emulsifying agent Span80 and Tween60 with mass ratio, and the massfraction that emulsifying agent accounts for kerosene is 6%; (2). water: is to take by weighing at 6.7: 1 2-methyl-2-acrylamido propanesulfonic acid (AMPS), methylacryoyloxyethyl trimethyl ammonium chloride (DMC) with mass ratio, be dissolved in and be mixed with monomer solution in the distilled water, regulating its pH value is 7, and monomer total mass mark is 55%; (3) oil phase and water were mixed to stir with 1: 2.3 make white milk sap, the emulsion that makes is moved in the 250mL there-necked flask, logical nitrogen, regulating bath temperature is 45 ℃, adds the 0.6% (NH that accounts for the monomer total mass 4) 2S 2O 8-Na 2SO 3Oxidation-reduction initiator places water bath with thermostatic control stirring reaction 6h, generates slightly pink colour viscous emulsion, promptly gets polymerisate; Prescription-1 concrete dosage sees Table 1:
Table 1 synthesizes AMPS/DMC amphoteric ion copolymer experimental formula-1
Medicine Dosage (g)
Kerosene distilled water Span-80 Tween-60 AMPS DMC (NH 4) 2S 2O 8-Na 2SO 3 15mL 35mL 0.75 0.15 16.7475 2.5025 0.1155
Prescription-2:(1). oil phase: is to be dissolved in kerosene at 4: 1 emulsifying agent Span80 and Tween60 with mass ratio, and the massfraction that emulsifying agent accounts for kerosene is 5%; (2). water: is to take by weighing at 8: 1 2-methyl-2-acrylamido propanesulfonic acid (AMPS), methylacryoyloxyethyl trimethyl ammonium chloride (DMC) with mass ratio, be dissolved in and be mixed with monomer solution in the distilled water, regulating its pH value is 7, and monomer total mass mark is 35%; (3) oil phase and water were mixed to stir with 1: 2 make white milk sap, the emulsion that makes is moved in the 250mL there-necked flask, logical nitrogen, regulating bath temperature is 30 ℃, adds the 0.4% (NH that accounts for the monomer total mass 4) 2S 2O 8-Na 2SO 3Oxidation-reduction initiator places water bath with thermostatic control stirring reaction 6h, generates slightly pink colour viscous emulsion, promptly gets polymerisate; Prescription-2 concrete dosages see Table 2:
Table 2 synthesizes AMPS/DMC amphoteric ion copolymer experimental formula-2
Medicine Dosage (g)
Kerosene distilled water Span-80 Tween-60 AMPS DMC (NH 4) 2S 2O 8-Na 2SO 3 17mL 34mL 0.68 0.17 10.5778 1.3222 0.0476
Embodiment 2 AMPS/DMC amphoteric ion polymer acid solution tackifyings
See Fig. 1, acid solution is 20%HCl, and along with experimental formula-1 multipolymer dosage increases, the viscosity of polymkeric substance in acid solution rises, and shows that this multipolymer has tackifying preferably as viscosifying agent in acid solution.
The thermostability of embodiment 3 AMPS/DMC amphoteric ion polymers in acid solution
In 20%HCl, add massfraction and be 3% experimental formula-1 multipolymer and be mixed with 3% gelled acid, see Fig. 2, the apparent viscosity of gelled acid acid solution descends from 30 ℃ to 90 ℃ slowly, shows that the AMPS/DMC amphoteric ion copolymer has good thermostability as viscosifying agent in acid solution.
The salt resistance of embodiment 4 AMPS/DMC amphoteric ion polymers
In 20%HCl, add massfraction and be 3% experimental formula-2 multipolymer and be mixed with 3% gelled acid; See Fig. 3, when the massfraction of inorganic salt dosage at 0.2%-0.3%, the apparent viscosity of gelled acid acid solution increases with salinity and rises, show that this amphiphilic polymers has certain salt thickening property, when the inorganic salt dosage greater than 0.3%, the apparent viscosity of acid solution tends to be steady, and shows that this multipolymer has salt resistance preferably in acid solution.
The shear stability of embodiment 5 AMPS/DMC amphoteric ion polymers in acid solution
In 20%HCl, add massfraction and be 3% prescription-2 multipolymer and be mixed with 3% gelled acid, under the room temperature, 170s -1Shear 120min down continuously; See Fig. 4,40min gelled acid acid solution apparent viscosity drops to 17.2mPas from 18.6mPas before shearing, and it is almost constant to clip to 120min acid solution apparent viscosity from 40min, shows that this amphoteric ion copolymer has good shear stability in acid solution.
The structural characterization of embodiment 6 AMPS/DMC amphoteric ion polymers
The infrared spectrum of the AMPS/DMC amphoteric ion copolymer that makes is seen Fig. 5, learns 3462cm from Fig. 5 -1The place is-the NH-charateristic avsorption band; Because polymkeric substance has strong water-absorbent, polymkeric substance contains a small amount of combination water, so>3000cm -1The vibration broad peak appears in the place; 3071cm -1The place is-N +(CH 3) 3The charateristic avsorption band of last methyl; 2933cm -1The place is-CH 3,-CH 2-vibration absorption peak; 1664cm -1The place is amidocarbonylation stretching vibration absorption peak; 1726cm -1The place is the charateristic avsorption band of acyl-oxygen group; 1458cm -1The place is-CH 2-N +(CH 3) 3The flexural vibration absorption peak of methylene radical; Show that product is that AMPS and two kinds of monomer copolymerizations of DMC are synthetic and obtains.

Claims (2)

1. a water soluble amphoteric ion copolymer is made up of 2-methyl-2-acrylamido propanesulfonic acid and two kinds of structural units of methylacryoyloxyethyl trimethyl ammonium chloride, and the structural formula of this multipolymer is:
Figure C2006100209120002C1
Wherein x: y is 6~9: 1.
2. the preparation method of amphoteric ion copolymer as claimed in claim 1 may further comprise the steps successively:
(1) preparation oil phase: with the emulsifying agent sorbitan monooleate with to have 20 polyoxyethylene chain sorbitan monostearates be to join in kerosene at 4~6: 1 with mass ratio, the massfraction that emulsifying agent accounts for kerosene is 5~10%;
(2) preparation water: is to take by weighing at 6~9: 1 2-methyl-2-acrylamido propanesulfonic acid, methylacryoyloxyethyl trimethyl ammonium chloride with mass ratio, and pH value soluble in water respectively and that regulate monomer solution is 7, and monomer total mass mark is 35~55%;
(3) be 1: 0.5~2.3 mixing with oil phase and water with volume ratio, stir and form white milk sap, logical nitrogen, regulate bath temperature at 30~55 ℃, add water-soluble ammonium persulphate-S-WAT redox initiator, the initiator dosage is 0.2~0.6% of a monomer total mass, places water bath with thermostatic control stirring reaction 4~6h, get dope, be copolymer emulsion.
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