阅读说明：本技术 一种随钻传感器硅橡胶气液分离膜的制备方法 (Preparation method of while-drilling sensor silicon rubber gas-liquid separation membrane ) 是由 卢国龙 孙友宏 刘嵩 常志勇 谢宗池 崔浩 翁小辉 于 2020-05-07 设计创作，主要内容包括：本发明公开了一种随钻传感器硅橡胶气液分离膜的制备方法。本发明利用聚二甲基硅氧烷的双键和氯甲基聚醚砜发生赫克偶联反应,在聚二甲基硅氧烷分子链上引入了聚醚砜支链,在分子链长度不变的情况下,增大了分离膜与待分离气液混合物接触面积,从而加快传质；同时聚醚砜及聚二甲基硅氧烷分子链都是空间螺旋结构,聚醚砜的引入改善硅橡胶的空间结构,使其力学性能得到提升；本发明通过化学反应改变分子结构,聚二甲基硅氧烷与聚醚砜通过化学键连接,从而得到新的化学物质,以适合随钻检测,使得渗透烯烃和甲烷的能力更强,并且化学键增加力学性能,能够承受更大的压力,并且成本低、结构简单、材料价廉易得,性能稳定、分离效率高。(The invention discloses a preparation method of a while-drilling sensor silicon rubber gas-liquid separation membrane. According to the invention, double bonds of polydimethylsiloxane and chloromethyl polyether sulfone are subjected to a heck coupling reaction, polyether sulfone branched chains are introduced on the molecular chains of the polydimethylsiloxane, and the contact area of a separation membrane and a gas-liquid mixture to be separated is increased under the condition of unchanging the length of the molecular chains, so that the mass transfer is accelerated; meanwhile, molecular chains of the polyether sulfone and the polydimethylsiloxane are of spatial spiral structures, and the introduction of the polyether sulfone improves the spatial structure of the silicone rubber, so that the mechanical property of the silicone rubber is improved; the molecular structure is changed through chemical reaction, the polydimethylsiloxane and the polyether sulfone are connected through chemical bonds, so that a new chemical substance is obtained, the detection while drilling is suitable, the capability of permeating olefin and methane is higher, the mechanical property is increased through the chemical bonds, higher pressure can be borne, the cost is low, the structure is simple, the materials are cheap and easy to obtain, the performance is stable, and the separation efficiency is high.)

1. The preparation method of the while-drilling sensor silicone rubber gas-liquid separation membrane is characterized by comprising the following steps:

1) preparation of chloromethylated polyethersulfone:

putting the polyethersulfone, a chloromethylation reagent and a catalyst for the chloromethylation reaction into a solvent, carrying out the chloromethylation reaction on aromatic hydrocarbon and chloromethyl in a polyethersulfone molecular chain under the action of the catalyst for the chloromethylation reaction, so that hydrogen atoms on the aromatic hydrocarbon are replaced by chloromethyl, introducing chloromethyl on the aromatic hydrocarbon in the polyethersulfone molecular chain to form chloromethylated polyethersulfone, and precipitating to obtain the chloromethylated polyethersulfone;

2) preparing a silicon rubber membrane casting solution:

adding polydimethylsiloxane, a cross-linking agent and a catalyst for cross-linking reaction into a solvent for reaction, performing cross-linking reaction,

obtaining a silicon rubber membrane casting solution;

3) obtaining a modified silicon rubber gas-liquid separation membrane casting solution:

adding the chloromethylated polyether sulfone obtained in the step 1) and a catalyst of a heck coupling reaction into the silicon rubber membrane casting solution obtained in the step 2), fully mixing the chloromethylated polyether sulfone with the silicon rubber membrane casting solution, carrying out the heck coupling reaction at a set temperature, wherein polydimethylsiloxane molecules in the silicon rubber membrane casting solution have a carbon-carbon double bond structure, the chloromethylated polyether sulfone has a potassium chloride group, the double bond structure and chloromethyl carry out the heck coupling reaction under the catalytic action of the catalyst of the heck coupling reaction, and chloromethyl on aromatic hydrocarbon in a molecular chain of the chloromethylated polyether sulfone is introduced onto the carbon-carbon double bond in the polydimethylsiloxane molecules through the heck coupling reaction to form a crosslinked polyether sulfone-polydimethylsiloxane copolymer, so as to obtain a modified silicon rubber gas-liquid separation membrane casting solution;

4) obtaining the modified silicon rubber gas-liquid separation membrane:

uniformly coating the modified silicon rubber gas-liquid separation membrane casting solution on a smooth and clean coating flat plate, drying in vacuum under a set temperature condition, and demoulding after drying to obtain the modified silicon rubber gas-liquid separation membrane; the molecular chain of the polyether sulfone is of a spatial spiral structure, so that the molar volume of the crosslinked polyether sulfone-polydimethylsiloxane copolymer is remarkably increased, and the introduction of the polyether sulfone ensures that the molecules are disordered to ordered, and the distance between adjacent molecules is orderly increased, so that a continuous and ceaseless moving channel is formed inside the modified silicone rubber gas-liquid separation membrane, the mass transfer of gas components in the modified silicone rubber gas-liquid separation membrane is promoted, and the permeability of the polydimethylsiloxane is enhanced; under the condition that the length of a Si-O chain with carbon-carbon double bonds in polydimethylsiloxane molecules is not changed, the molecular surface area is increased, namely the contact area of the modified silicon rubber gas-liquid separation membrane and a gas-liquid mixture to be separated is increased, so that the mass transfer is accelerated; meanwhile, molecular chains of the polyether sulfone and the polydimethylsiloxane are both in a spatial spiral structure, polyether sulfone cross-linked polydimethylsiloxane is introduced, the spatial structures of the two polymers are limited together, the mechanical property of the two polymers is improved, the two polymers can bear higher pressure, the polyether sulfone is an oil-resistant group, and the detection while drilling oil resistance of the modified silicone rubber gas-liquid separation membrane is enhanced by introducing the polyether sulfone, so that the underground service time is prolonged.

2. The method according to claim 1, wherein the chloromethylation reaction is carried out at 30-60 ℃ in step 1); the reaction time is 4-8 h; the mass ratio of the polyether sulfone to the chloromethylation reagent to the catalyst for the chloromethylation reaction is as follows: 1 (0.25-0.3) and (0.03-0.04).

3. The method according to claim 1, wherein in step 1), the chloromethylation reagent is mixed with hydrochloric acid in equal proportion to chloromethylation reagent aldehyde, and the chloromethylation reagent aldehyde is formaldehyde, trioxymethylene or paraformaldehyde; the catalyst for the chloromethylation reaction adopts one of protonic acid, concentrated sulfuric acid and hydrochloric acid; the solvent is an inert solvent of chlorinated hydrocarbon.

4. The method according to claim 1, wherein in step 2), the crosslinking agent is an alkoxysilane; the catalyst adopts organic tin salt; the solvent is a non-polar solvent.

5. The method according to claim 1, wherein in step 2), the mass ratio of polydimethylsiloxane, the crosslinking agent and the catalyst for the crosslinking reaction is 10: (1-2): (0.1-0.5).

6. The method according to claim 1, wherein in step 3), the reaction temperature of the heck coupling reaction is 30 to 60 ℃; the equivalent ratio of the chloromethylated polyether sulfone to the catalyst for the heck coupling reaction is 1 (0.4-0.6).

7. The process according to claim 1, wherein in step 3), palladium acetate is used as catalyst for the heck coupling reaction, and the palladium acetate provides alkaline conditions for the reaction.

8. The preparation method according to claim 1, wherein in the step 4), the temperature of vacuum drying is 80 to 105 ℃; the vacuum drying time is 4-8 h.

9. The method according to claim 1, wherein in the step 4), the modified silicone rubber gas-liquid separation membrane has a thickness of 50 to 200 μm.

Technical Field

The invention relates to the field of silicone rubber gas-liquid separation membranes, in particular to a preparation method of a while-drilling sensor silicone rubber gas-liquid separation membrane.

Background

Oil and gas is an important resource on which human beings rely for survival, and in recent years, people have to develop new alternative energy sources and explore other energy sources due to shortage of oil resources. In the process of oil and gas exploration and drilling, finding a hydrocarbon reservoir and determining the specific position and the productivity of the hydrocarbon reservoir are important, and logging is an important means for achieving the purpose. With the rapid development of technologies such as measurement while drilling, logging while drilling and the like, the underground gas separation while drilling detection technology has the characteristics of timeliness, continuity, quantification and the like, so that on one hand, gas components including hydrocarbon gases such as methane, acetylene and the like in an underground gas-liquid mixture to be separated can be detected in time, the light hydrocarbon content of a stratum in a drilling process can be quantitatively mastered, help is provided for a drilling construction decision, and the drilling efficiency is improved; on the other hand, the method is beneficial to finding out abnormal conditions such as well kick, blowout and the like as soon as possible, improves the safety of drilling work, and becomes a main development trend of the logging industry.

The silicon rubber (the main component is polydimethylsiloxane) is a gas-liquid separation membrane material, and due to the excellent chemical properties of the silicon rubber, such as the characteristics of small interaction force, large molar volume, small surface tension and the like among Si-O chains due to the spiral structure of the Si-O chains, the mass transfer process of gas components in the membrane is promoted, so that the polydimethylsiloxane has strong permeability. Therefore, the silicone rubber membrane is widely used in gas separation processes. Fig. 1 is a schematic structural view of a conventional silicone rubber gas-liquid separation membrane. However, the application of a pure silicone rubber membrane in a sensor while drilling under a severe environment is limited due to the low mechanical property of silicone rubber. Fig. 2 is a schematic view of a conventional silicone rubber composite film.

Polyethersulfone (PES) membranes have very important applications in military, civilian and scientific research. The polyethersulfone membrane material plays a crucial role in the development of pervaporation technology due to the advantages of high pressure resistance, heat resistance, oxidation resistance, excellent mechanical property and the like, and is still the preferred material system in important strategic and tactical applications. However, since the permeation rate of the gas-liquid separation membrane of the while-drilling sensor determines the detection efficiency while drilling to a great extent, the use of the polyethersulfone membrane on the while-drilling sensor is greatly limited due to the low mass transfer efficiency of the drilling fluid.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a preparation method of a while-drilling sensor silicon rubber gas-liquid separation membrane.

The preparation method of the while-drilling sensor silicon rubber gas-liquid separation membrane comprises the following steps:

1) preparation of chloromethylated polyethersulfone:

putting the polyethersulfone, a chloromethylation reagent and a catalyst for the chloromethylation reaction into a solvent, carrying out the chloromethylation reaction on aromatic hydrocarbon and chloromethyl in a polyethersulfone molecular chain under the action of the catalyst for the chloromethylation reaction, so that hydrogen atoms on the aromatic hydrocarbon are replaced by chloromethyl, introducing chloromethyl on the aromatic hydrocarbon in the polyethersulfone molecular chain to form chloromethylated polyethersulfone, and precipitating to obtain the chloromethylated polyethersulfone;

2) preparing a silicon rubber membrane casting solution:

adding polydimethylsiloxane, a cross-linking agent and a catalyst for cross-linking reaction into a solvent for reaction, and obtaining a silicon rubber membrane casting solution through the cross-linking reaction;

3) obtaining a modified silicon rubber gas-liquid separation membrane casting solution:

adding the chloromethylated polyether sulfone obtained in the step 1) and a catalyst of a heck coupling reaction into the silicon rubber membrane casting solution obtained in the step 2), fully mixing the chloromethylated polyether sulfone with the silicon rubber membrane casting solution, carrying out the heck coupling reaction at a set temperature, wherein polydimethylsiloxane molecules in the silicon rubber membrane casting solution have a carbon-carbon double bond structure, the chloromethylated polyether sulfone has a potassium chloride group, the double bond structure and chloromethyl carry out the heck coupling reaction under the catalytic action of the catalyst of the heck coupling reaction, and chloromethyl on aromatic hydrocarbon in a molecular chain of the chloromethylated polyether sulfone is introduced onto the carbon-carbon double bond in the polydimethylsiloxane molecules through the heck coupling reaction to form a crosslinked polyether sulfone-polydimethylsiloxane copolymer, so as to obtain a modified silicon rubber gas-liquid separation membrane casting solution;

4) obtaining the modified silicon rubber gas-liquid separation membrane:

uniformly coating the modified silicon rubber gas-liquid separation membrane casting solution on a smooth and clean coating flat plate, drying in vacuum under a set temperature condition, and demoulding after drying to obtain the modified silicon rubber gas-liquid separation membrane; the molecular chain of the polyether sulfone is of a spatial spiral structure, so that the molar volume of the crosslinked polyether sulfone-polydimethylsiloxane copolymer is remarkably increased, and the introduction of the polyether sulfone ensures that the molecules are disordered to ordered, and the distance between adjacent molecules is orderly increased, so that a continuous and ceaseless moving channel is formed inside the modified silicone rubber gas-liquid separation membrane, the mass transfer of gas components in the modified silicone rubber gas-liquid separation membrane is promoted, and the permeability of the polydimethylsiloxane is enhanced; under the condition that the length of a Si-O chain with carbon-carbon double bonds in polydimethylsiloxane molecules is not changed, the molecular surface area is increased, namely the contact area of the modified silicon rubber gas-liquid separation membrane and a gas-liquid mixture to be separated is increased, so that the mass transfer is accelerated; meanwhile, molecular chains of the polyether sulfone and the polydimethylsiloxane are both in a spatial spiral structure, polyether sulfone cross-linked polydimethylsiloxane is introduced, the spatial structures of the two polymers are limited together, the mechanical property of the two polymers is improved, the two polymers can bear higher pressure, the polyether sulfone is an oil-resistant group, and the detection while drilling oil resistance of the modified silicone rubber gas-liquid separation membrane is enhanced by introducing the polyether sulfone, so that the underground service time is prolonged.

Wherein, in the step 1), the reaction temperature of the chloromethylation reaction is 30-60 ℃; the reaction time is 4-8 h; the mass ratio of the polyether sulfone to the chloromethylation reagent to the catalyst for the chloromethylation reaction is as follows: 1 (0.25-0.3) and (0.03-0.04). The chloromethylation reagent adopts hydrochloric acid and chloromethylation reagent aldehyde which are mixed in equal proportion, and the chloromethylation reagent aldehyde adoptsFormaldehyde, trioxymethylene or paraformaldehyde. The catalyst for the chloromethylation reaction adopts one of protonic acid, concentrated sulfuric acid and hydrochloric acid. The solvent is an inert solvent of chlorinated hydrocarbon, CHCl₂、CHCl₃And C₂H₄Cl₂And the like.

In the step 2), the cross-linking agent is one of alkoxysilanes, ethyl orthosilicate, aminopropyl triethoxysilane and chloropropyl trimethoxysilane, polydimethylsiloxane belongs to high molecules, the molecular distance is large, the cross-linking agent belongs to a short-chain molecular structure, the physical effect is realized in the reaction process, and a plurality of high molecules are connected in series, so that the structure is stable, and a good bonding effect is achieved. The catalyst for the crosslinking reaction adopts organic tin salt, dibutyltin dilaurate or stannous octoate and the like to form a coordination compound so as to reduce the reaction activation energy. The solvent is non-polar solvent, n-hexane, cyclohexane, n-heptane or isooctane. The mass ratio of the polydimethylsiloxane to the cross-linking agent to the catalyst for the cross-linking reaction is 10: (1-2): (0.1-0.5).

In the step 3), the reaction temperature of the heck coupling reaction is 30-60 ℃; the equivalent ratio of the chloromethylated polyether sulfone to the catalyst for the heck coupling reaction is 1 (0.4-0.6). The catalyst for the heck coupling reaction adopts palladium acetate, and the palladium acetate provides an alkaline condition for the reaction.

In the step 4), the temperature of vacuum drying is 80-105 ℃; the vacuum drying time is 4-8 h. The thickness of the modified silicon rubber gas-liquid separation membrane is 50-200 mu m.

The invention has the advantages that:

the invention utilizes double bonds of polydimethylsiloxane and chloromethyl polyether sulfone to generate heck coupling reaction, and introduces polyether sulfone branched chains on Si-O chains with carbon-carbon double bonds in the polydimethylsiloxane molecules. Under the condition that the length of a Si-O chain with a carbon-carbon double bond in a polydimethylsiloxane molecule is not changed, the contact area of a separation membrane and a gas-liquid mixture to be separated is increased, so that mass transfer is accelerated; meanwhile, molecular chains of the polyether sulfone and the polydimethylsiloxane are of spatial spiral structures, and the introduction of the polyether sulfone can improve the spatial structure of the silicone rubber and improve the mechanical property of the silicone rubber; compared with the prior art, the polyether sulfone is coated on the silicon rubber separation membrane, the silicon rubber and the polyether sulfone are physically mixed, chloromethyl is introduced into the polyether sulfone, so that polydimethylsiloxane and chloromethylated polyether sulfone are mixed in a liquid phase to generate a heck coupling reaction, the molecular structure is changed through a chemical reaction, and the polydimethylsiloxane and the polyether sulfone are connected through a chemical bond to obtain a new chemical substance so as to be suitable for detection while drilling, so that the capability of permeating olefin and methane is stronger, the chemical bond has increased mechanical property and can bear higher pressure; the invention has the advantages of low production cost, simple structure, cheap and easily obtained materials, stable performance, high separation efficiency, and stronger mechanical strength and oil resistance so as to be suitable for long-time use in drilling fluid and other environments.

Drawings

FIG. 1 is a schematic structural view of a conventional gas-liquid separation membrane for silicone rubber;

FIG. 2 is a schematic view of a conventional silicone rubber composite membrane;

FIG. 3 is a structural formula of polydimethylsiloxane;

FIG. 4 is a structural formula of polyethersulfone;

FIG. 5 is a structural formula of chloromethyl polyether sulfone obtained according to one embodiment of the preparation method of the while-drilling sensor silicone rubber gas-liquid separation membrane of the present invention;

FIG. 6 is a schematic structural diagram of a modified silicone rubber gas-liquid separation membrane obtained according to one embodiment of the preparation method of the while-drilling sensor silicone rubber gas-liquid separation membrane of the invention;

FIG. 7 is a structural formula of a cross-linked polyethersulfone-polydimethylsiloxane copolymer obtained according to one embodiment of the preparation method of the while-drilling sensor silicone rubber gas-liquid separation membrane.

Detailed Description

The invention will be further elucidated by means of specific embodiments in the following with reference to the drawing.

As shown in fig. 1, the preparation method of the while-drilling sensor silicone rubber gas-liquid separation membrane of the embodiment includes the following steps:

1) preparation of chloromethylated polyethersulfone solvent:

dissolving 10g of polyethersulfone in 100mL of chloroform, wherein the structural formula of the polyethersulfone is shown in figure 4, stirring at room temperature until the polyethersulfone is completely dissolved, slowly cooling the temperature to the reaction temperature, then adding 2.5g of formaldehyde and 3g of hydrochloric acid, pouring the reaction solution into deionized water after the reaction is completely carried out, separating out white filamentous precipitate, repeatedly washing the white filamentous precipitate with the deionized water for multiple times, and carrying out vacuum drying to obtain chloromethylated polyethersulfone, wherein the structural formula of the chloromethylated polyethersulfone is shown in figure 5;

2) preparing a silicon rubber membrane casting solution:

mixing polydimethylsiloxane, ethyl orthosilicate and dibutyltin dilaurate according to the weight ratio of 10: 1: 0.5, adding the mixture into a single-neck flask containing a solvent of n-heptane, uniformly mixing the mixture, and performing crosslinking reaction to obtain a silicone rubber membrane casting solution, wherein the structural formula of polydimethylsiloxane is shown in figure 3;

3) obtaining a silicon rubber gas-liquid separation membrane casting solution:

adding 0.05 chemical equivalent of palladium acetate and 0.1 chemical equivalent of chloromethyl polyether sulfone into the silicon rubber membrane casting solution, stirring for 0.5h under the reaction condition of 30 ℃, and carrying out heck coupling reaction to obtain the modified silicon rubber gas-liquid separation membrane casting solution, wherein the structural formula of the crosslinked polyether sulfone-polydimethylsiloxane copolymer is shown in figure 7;

4) obtaining the modified silicon rubber gas-liquid separation membrane:

and uniformly coating the modified silicone rubber membrane casting solution on a smooth and clean coating flat plate, scraping a membrane with the thickness of 50-200 mu m by using a scraper or an automatic membrane scraping machine, drying the membrane for 8 hours in vacuum at the temperature of 80 ℃, and removing the membrane to obtain the modified silicone rubber separation membrane.

As shown in fig. 6, a continuous and continuous moving "channel" is formed inside the obtained modified silicone rubber separation membrane, so that the mass transfer process of gas components in the modified silicone rubber gas-liquid separation membrane is promoted, and the polydimethylsiloxane has stronger permeability; under the condition that the length of a Si-O chain with a carbon-carbon double bond in a polydimethylsiloxane molecule is not changed, the distance between adjacent molecules is orderly increased, and the contact area of the modified silicon rubber gas-liquid separation membrane and a gas-liquid mixture to be separated is increased, so that the mass transfer is accelerated; meanwhile, molecular chains of the polyether sulfone and the polydimethylsiloxane are of spatial spiral structures, the introduction of the polyether sulfone improves the spatial structure of the polydimethylsiloxane, so that the mechanical property of the polydimethylsiloxane is improved, the polydimethylsiloxane can bear higher pressure, the polyether sulfone is an oil-resistant group, and the introduction of the polyether sulfone enhances the oil resistance of the modified silicone rubber gas-liquid separation membrane during the detection while drilling, so that the underground service time is prolonged.

Finally, it is noted that the disclosed embodiments are intended to aid in further understanding of the invention, but those skilled in the art will appreciate that: various substitutions and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the invention should not be limited to the embodiments disclosed, but the scope of the invention is defined by the appended claims.