阅读说明：本技术 一种聚合物及其制备方法与在作为或制备控砂剂中的应用 (Polymer, preparation method thereof and application of polymer as or in preparation of sand control agent ) 是由 宋金波 汪庐山 李常友 刘玉国 孙秀钊 高雪峰 董海生 武明鸣 梅明霞 张锡娟 于 2019-03-25 设计创作，主要内容包括：本发明公开了一种聚合物,结构式如图1所示,其制备方法为：(1)反应物聚环氧乙烷和磷酸酯,在催化剂对甲苯磺酸的作用下,进行酯化反应,得反应液；(2)将上述反应液调至弱酸性,在常压下加入聚糠醇,进行醚化反应,所得产物为红棕色粘稠状液体。本发明的聚合物,可作为或用于制备控砂剂。本发明的聚合物,为新型非离子型磷酸酯覆膜控砂剂,其以磷酸为联结基团,通过酯化反应引入聚环氧乙烷链段,获得弱酸性二取代磷酸酯；在弱酸性条件下,再引入具有缓控固化的聚糠醇链段,从而实现高强度、原位固定地层微粒的效果。(The invention discloses a polymer, the structural formula of which is shown in figure 1, and the preparation method comprises the following steps: (1) carrying out esterification reaction on reactants polyethylene oxide and phosphate under the action of a catalyst p-toluenesulfonic acid to obtain reaction liquid; (2) and (3) adjusting the reaction liquid to be weakly acidic, adding polyfurfuryl alcohol under normal pressure, and carrying out etherification reaction to obtain a reddish brown viscous liquid. The polymer of the invention can be used as or for preparing a sand control agent. The polymer is a novel nonionic phosphate coated sand control agent, phosphoric acid is used as a connecting group, and a polyethylene oxide chain segment is introduced through esterification reaction to obtain weak-acidic disubstituted phosphate; under the weak acidic condition, a polyfurfuryl alcohol chain segment with slow-control solidification is introduced, so that the effect of high-strength in-situ fixing stratum particles is realized.)

1. A polymer having the formula:

wherein m is 5 to 100, and n is 2 to 10.

2. The polymer of claim 1, wherein: m is 10, n is 2; or: m is 100, n is 10; or: m is 23, n is 5; or: m is 46 and n is 7.

3. A process for the preparation of a polymer according to claim 1 or 2, characterized in that: the method comprises the following steps:

(1) carrying out esterification reaction on reactants polyethylene oxide and phosphate under the action of a catalyst p-toluenesulfonic acid, wherein the reaction pressure is 0.8-1.0 MPa, the reaction temperature is 110-180 ℃, and the reaction time is 8-12 h, so as to obtain a reaction solution;

(2) adjusting the reaction liquid to be weakly acidic, adding polyfurfuryl alcohol under normal pressure, and carrying out etherification reaction at the reaction temperature of 50-70 ℃ for 4-6 h; after the reaction, the product was a reddish brown viscous liquid.

4. A method of preparing a polymer according to claim 3, characterized in that: the molar ratio of the polyethylene oxide to the phosphate ester is 2: 1; or/and: the addition amount of the p-toluenesulfonic acid is 0.1 percent of the weight of reactants; or/and: the molar ratio of the polyfurfuryl alcohol to the polyethylene oxide in the step (1) is 1: 1.

5. Use of a polymer according to claim 1 or 2 as or in the preparation of a sand control agent.

6. A preparation method of phosphate coated sand control agent is characterized by comprising the following steps: the method comprises the following steps:

(1) carrying out esterification reaction on reactants polyethylene oxide and phosphate under the action of a catalyst p-toluenesulfonic acid, wherein the reaction pressure is 0.8-1.0 MPa, the reaction temperature is 110-180 ℃, and the reaction time is 8-12 h, so as to obtain a reaction solution; the molecular weight of the polyethylene oxide is 220-4400;

(2) adjusting the reaction liquid to be weakly acidic, adding polyfurfuryl alcohol under normal pressure, and carrying out etherification reaction at the reaction temperature of 50-70 ℃ for 4-6 h; the molecular weight of the polyfurfuryl alcohol is 196-980; after the reaction, the product was a reddish brown viscous liquid.

7. The preparation method of the phosphate coated sand control agent according to claim 6, characterized in that: the molar ratio of the polyethylene oxide to the phosphate ester is 2: 1; or/and: the addition amount of the p-toluenesulfonic acid is 0.1 percent of the weight of reactants; or/and: the molar ratio of the polyfurfuryl alcohol to the polyethylene oxide in the step (1) is 1: 1.

8. The phosphate coated sand control agent prepared by the preparation method of the phosphate coated sand control agent according to claim 6 or 7.

9. The use of the phosphate coated sand control agent of claim 8 in the preparation of a sand control agent emulsion.

10. A sand control agent emulsion is characterized in that: the mass concentration of the sand control agent is 20 percent; the sand control agent is the sand control agent of claim 8.

Technical Field

The invention relates to a polymer, a preparation method thereof and application thereof as or in preparation of a sand control agent, belonging to the technical field of preparation of sand control agents.

Background

In the middle and later period of development of oil fields, along with the increase of high mud quality, fine sand, aggregation and the like, the yield of the oil well after sand prevention is reduced quickly, the difficulty of extracting liquid is high, and the phenomenon of low liquid is obvious. How to effectively control the migration of particles such as clay, silt and the like in a reservoir and a filling zone becomes an effective means for solving the problems. The sand control agent commonly used at present mainly comprises inorganic salt, alkalis, inorganic polynuclear polymers and cationic polymers, and the cationic polymers are taken as main components. Cationic polymers can be dissolved and dissociated in water to produce polycations which can bridge clay particles to the surface of the formation to effectively inhibit particle migration by adsorbing and neutralizing the electronegativity of the clay surface, adsorbing between clay layers to bridge them and inhibit clay swelling. However, cationic polymers have the following disadvantages: firstly, the water-soluble cationic polymer can be dissolved into the formation water again along with the prolonging of the production time, the effective components remained on the surface wall of the pore can be denatured and broken chains under the influence of the formation mineralization and the shearing action, and the descending is rapid so as to lead the sand inhibiting performance to be sharply reduced; secondly, the cationic polymer remained on the surface walls of the pores and the particles has weak sand inhibiting performance and low scouring resistance only by electrostatic adsorption and hydrogen bonding; thirdly, reservoir damage can be caused by improper use of the medium-low permeability reservoir. Therefore, in order to solve the problems of fast oil well yield reduction, large difficulty in extracting liquid, low liquid content and the like caused by the migration of stratum particles, the development of a sand control agent capable of generating a viscous film and fixing the stratum particles in situ is urgently needed.

Disclosure of Invention

In view of the prior art, the invention provides a polymer, a preparation method thereof and application thereof as or in preparation of a sand control agent.

The invention is realized by the following technical scheme:

a polymer having the formula:

wherein m is 5 to 100, and n is 2 to 10.

The synthetic route of the polymer is as follows:

the preparation method of the polymer comprises the following steps:

(1) carrying out esterification reaction on reactants polyethylene oxide and phosphate under the action of a catalyst p-toluenesulfonic acid, wherein the reaction pressure is 0.8-1.0 MPa, the reaction temperature is 110-180 ℃, and the reaction time is 8-12 h, so as to obtain a reaction solution; the molecular weight of the polyethylene oxide is 220-4400 (m in the corresponding product is 5-100);

further, the molar ratio of polyethylene oxide to phosphate ester is 2: 1;

further, the p-toluenesulfonic acid is added in an amount of 0.1% by weight of the reactants (referring to the weight of the polyethylene oxide and the phosphate);

(2) adjusting the reaction liquid to be weakly acidic (pH is 4-6), adding polyfurfuryl alcohol under normal pressure, and carrying out etherification reaction at the reaction temperature of 50-70 ℃ for 4-6 h; the molecular weight of the polyfurfuryl alcohol is 196-980 (n in the corresponding product is 2-10); after the reaction, the obtained product is reddish brown viscous liquid, namely the polymer.

Further, the molar ratio of the polyfurfuryl alcohol to the polyethylene oxide in the step (1) is 1: 1.

The polymer can be used as a main agent of the sand control agent or used for preparing the sand control agent (such as an emulsion of the sand control agent) when being applied.

The invention also provides a phosphate coated sand control agent, and the preparation method comprises the following steps:

(1) carrying out esterification reaction on reactants polyethylene oxide and phosphate under the action of a catalyst p-toluenesulfonic acid, wherein the reaction pressure is 0.8-1.0 MPa, the reaction temperature is 110-180 ℃, and the reaction time is 8-12 h, so as to obtain a reaction solution; the molecular weight of the polyethylene oxide is 220-4400;

further, the molar ratio of polyethylene oxide to phosphate ester is 2: 1;

further, the p-toluenesulfonic acid is added in an amount of 0.1% by weight of the reactants (referring to the weight of the polyethylene oxide and the phosphate);

(2) adjusting the reaction liquid to be weakly acidic (pH is 4-6), adding polyfurfuryl alcohol under normal pressure, and carrying out etherification reaction at the reaction temperature of 50-70 ℃ for 4-6 h; the molecular weight of the polyfurfuryl alcohol is 196-980; after the reaction, the product was a reddish brown viscous liquid.

Further, the molar ratio of the polyfurfuryl alcohol to the polyethylene oxide in the step (1) is 1: 1.

The phosphate coated sand control agent can be used for preparing a sand control agent emulsion, such as a sand control agent emulsion with the mass concentration of 20%.

The polymer is a novel nonionic phosphate coated sand control agent, phosphoric acid is used as a connecting group, and a polyethylene oxide chain segment is introduced through esterification reaction to obtain weak-acidic disubstituted phosphate; under the weak acidic condition, a polyfurfuryl alcohol chain segment with slow-control solidification is introduced, so that the effect of high-strength in-situ fixing stratum particles is realized.

The polymer and phosphate coated sand control agent has the following advantages:

(1) the phosphoric acid in the polymer structure is used as a linking group on one hand and is also a catalyst for the curing reaction of the polyfurfuryl alcohol on the other hand.

(2) The polyethylene oxide temperature-sensitive chain segment is introduced, when the temperature rises and exceeds the cloud point (cloud point is 40-110 ℃) after the sand control agent is injected into a high-temperature oil well, the hydrogen bond between the polyethylene glycol chain segment and free water is destroyed, and the hydrophobicity of the polymer is enhanced, so that the sand control agent molecules can be adsorbed on the surface of sand grains, the sand control agent is conveniently contacted with the surface layer of the sand grains, and the solidification reaction is carried out.

(3) Under the acidic condition, hydroxyl (-CH) at the tail end of the sand control agent₂-OH) and polar groups (Si-OH) on the surface of sand grains are easy to generate condensation reaction and are bonded through covalent bonds; meanwhile, cross-linking reaction can also occur between furfuryl alcohol chain segments to form a network polymer with a branched chain structure, and the network polymer can obviously enhance the bonding density and bonding strength among sand particles and enhance the sand fixing capacity of the sand control agent.

(4) The polymer contains a large amount of alkoxy and epoxy groups, the functional groups can form hydrogen bonds with polar groups (Si-OH) on the surface of sand grains after hydrolysis, Si-O-Si covalent bonds are formed after heating, curing and dehydration, and thus a layer of viscous film is formed on the surface of sand grains, the agglomeration effect among the sand grains is realized, and the purpose of in-situ fixing of stratum particles is achieved.

In a word, the polymer and the sand control agent can be adsorbed on the surface of sand grains to perform a curing reaction with the sand grains, so that the bonding density and the bonding strength among the sand grains are stronger, a layer of viscous film can be formed on the surface of the sand grains, the agglomeration among the sand grains is realized, and the beneficial effect of in-situ fixing of stratum particles is achieved.

The various terms and phrases used herein have the ordinary meaning as is well known to those skilled in the art.

Drawings

FIG. 1: the structural formula of the polymer of the invention.

FIG. 2: synthetic routes to the polymers of the invention.

FIG. 3: ir spectra of the polymers of the invention.

FIG. 4: nuclear magnetic resonance spectrum of the polymer of the invention.

Detailed Description

The present invention will be further described with reference to the following examples. However, the scope of the present invention is not limited to the following examples. It will be understood by those skilled in the art that various changes and modifications may be made to the invention without departing from the spirit and scope of the invention.

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.