Bio-based polyether, emulsifier containing bio-based polyether, and preparation method and application of emulsifier

Abstract

The invention discloses bio-based polyether, an emulsifier containing bio-based polyether, and a preparation method and application of the emulsifier. The bio-based polyether disclosed by the invention is prepared by reacting raw materials including phenolated lignin and an epoxy compound; wherein the phenolated lignin is selected from base catalysis modified phenolated lignin. Adding the phenolated lignin into water, adjusting the pH value, and after the phenolated lignin is completely dissolved, adding an epoxy compound for heating reaction to obtain the bio-based polyether. The preparation method comprises the following steps: uniformly mixing span and bio-based polyether to obtain the emulsifier containing bio-based polyether. The emulsifier containing bio-based polyether can be applied to the inverse emulsion synthesis process of acrylamide polymers, and can well emulsify and stabilize a polymerization reaction system. According to the emulsification system, the production cost of the acrylamide polymer emulsion is reduced, the performance and economical efficiency requirements of site construction can be met, and the practicability is relatively high.

Description

Technical Field

[0001] The present invention relates to the technical field of emulsifiers containing bio-based polyethers. Further, it relates to bio-based polyethers, emulsifiers containing bio-based polyethers, and their preparation methods and applications. Background Art

[0002] Inverse emulsion polymerization is a polymerization method in which an aqueous phase dissolved with monomers is dispersed into a "water-in-oil" (W / O) type through an emulsifier. The emulsifier plays a decisive role in the characteristics of the emulsion polymerization system. Before polymerization, the emulsifier can disperse and solubilize the monomers to form a relatively stable monomer emulsion, providing a place for initiating polymerization - monomer-swollen micelles. After polymerization, the emulsifier adsorbs on the surface of latex particles to stabilize the latex particles, preventing them from aggregating, ensuring that the polymer emulsion system has an appropriate solid content, proper viscosity, and good stability. By adjusting the chemical properties of the emulsifier, the polymerization behavior, particle size, and properties of the emulsion product can be adjusted.

[0003] Lignin has the second-largest reserves in nature after cellulose and is the second-largest natural organic matter. Industrial lignin is rich in sources and low in price and can be used as a raw material for producing oilfield chemicals. With the rising price of petrochemical raw materials and the increasing environmental protection requirements, green chemicals using low-cost natural renewable resources such as lignin have become an international hot research and development direction.

[0004] Natural lignin is a natural polyaromatic macromolecular compound composed of hydrophobic non-polar groups with a phenylpropane skeleton and hydrophilic polar groups such as phenolic groups. The main connection methods between the structural main bodies of lignin are ether bonds and carbon-carbon bonds. These two types of bonds have low molecular polarity, high bond energy, and are difficult to react. Moreover, the methoxy content is high, the hydroxyl content is low, and there is a large steric hindrance on the benzene ring, resulting in significantly insufficient reactivity. For commercially available industrial by-product lignin, due to the condensation reaction after chemical treatment, its reaction sites are even fewer. Therefore, although lignin has certain surface activity, its direct use as an emulsifier has unsatisfactory effects due to its poor performance, and its application market is greatly restricted. However, using lignin as a raw material for preparing emulsifiers can turn waste into treasure and significantly reduce the cost of emulsifiers. Summary of the Invention

[0005] To solve the problems in the existing technology, the present invention provides a bio-based polyether, an emulsifier containing the bio-based polyether, and their preparation methods and applications. The emulsification system containing the bio-based polyether of the present invention is composed of a bio-based polyether and a Span surfactant. Among them, the modified lignin surfactant A is obtained by first phenolicating lignin and then alkoxylating it. This emulsifier containing the bio-based polyether can be applied to the inverse emulsion synthesis process of acrylamide polymers, and can emulsify and stabilize the polymerization reaction system well. The emulsifier containing the bio-based polyether is used for the inverse emulsion synthesis of acrylamide polymers, and the obtained emulsion products have the characteristics of low gel content, higher molecular weight, better long-term storage stability, lower residual monomer content, and faster dissolution rate. This emulsification system reduces the production cost of acrylamide polymer emulsions, can meet the performance and economic requirements of on-site construction, and has high practicability. This emulsification system expands the raw material sources of surfactants. The bio-based polyether belongs to a natural surfactant, has high safety, can be biodegradable, and after being injected into the ground with acrylamide polymers, the phenylpropane structure of lignin can emulsify crude oil well, which is beneficial to the emulsification and production of crude oil.

[0006] One of the objectives of the present invention is to provide a bio-based polyether, which is prepared by reacting raw materials including phenolicated lignin and an epoxide. Among them, the phenolicated lignin is selected from alkali-catalyzed modified phenolicated lignin.

[0007] Another objective of the present invention is to provide a preparation method of the bio-based polyether, which includes the following steps:

[0008] Add phenolicated lignin to water, adjust the pH, and wait until the phenolicated lignin is completely dissolved. Then add an epoxide for heating reaction to obtain the bio-based polyether. Among them, the phenolicated lignin is selected from alkali-catalyzed modified phenolicated lignin.

[0009] In the preparation method of the bio-based polyether of the present invention, preferably,

[0010] The epoxide is selected from at least one of ethylene oxide and propylene oxide; and / or,

[0011] Adjust the pH value to 10.5 - 11.5; and / or,

[0012] Based on the total mass of the phenolicated lignin, epoxide, and water added in this step being 100%,

[0013] The addition amount of the phenolicated lignin is 15wt% - 30wt%;

[0014] The addition amount of the epoxide is 0.15wt% - 3wt%; the rest is water;

[0015] The temperature of the heating reaction is 50 - 65°C; and / or,

[0016] The time of the heating reaction is 0.5 - 1.5 h; and / or,

[0017] The pressure of the heating reaction is (-0.1) - (-0.2) MPa.

[0018] In the preparation method of the bio - based polyether described in the present invention, after the reaction ends and during the purification treatment, first adjust the pH value to 6.5 - 7.5.

[0019] In the preparation method of the bio - based polyether described in the present invention, preferably,

[0020] The preparation method of the phenolic lignin includes:

[0021] Under closed conditions, after the raw materials including lignin, phenolic modifier, and alkaline catalyst are subjected to a contact reaction in water, optionally adjust the pH to obtain phenolic lignin;

[0022] Preferably,

[0023] The lignin is selected from at least one of alkali lignin and enzymatic hydrolysis lignin; and / or,

[0024] The phenolic modifier is selected from at least one of phenol and hydroquinone; and / or,

[0025] The alkaline catalyst is selected from at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, sodium bicarbonate, and ammonia water; and / or,

[0026] Calculated based on the total mass of the lignin, phenolic modifier, alkaline catalyst, and water added in this step being 100%, the addition amount of lignin is 10 - 15 wt%;

[0027] The mass ratio of the phenolic modifier to the lignin is 0.2 - 0.4:1;

[0028] The mass ratio of the alkaline catalyst to the lignin is 0.12 - 0.3:1; the rest is water; and / or,

[0029] Adjust the pH = 2 - 3; and / or,

[0030] The temperature of the contact reaction is 70 - 85 °C; and / or,

[0031] The contact reaction time is 0.5 - 2 h.

[0032] The third object of the present invention is to provide an emulsifier containing a bio - based polyether, and the emulsifier includes span and a bio - based polyether;

[0033] The bio - based polyether is selected from the bio - based polyether described in the first object of the present invention or the bio - based polyether described in any one of the second objects of the present invention.

[0034] In the emulsifier containing bio - based polyether according to the present invention, preferably,

[0035] In the emulsifier,

[0036] the content of Span is 60 - 85 wt%;

[0037] the content of bio - based polyether is 15 - 40 wt%;

[0038] Preferably,

[0039] the content of Span is 65 - 75 wt%;

[0040] the content of bio - based polyether is 25 - 35 wt%.

[0041] In the emulsifier containing bio - based polyether according to the present invention, preferably,

[0042] the Span is selected from at least one of Span 60, Span 80, and Span 83.

[0043] The fourth object of the present invention is to provide a preparation method of the emulsifier containing bio - based polyether according to any one of the third objects of the present invention, comprising the following steps:

[0044] Mix the Span and the bio - based polyether evenly to obtain the emulsifier.

[0045] In the present invention, there is no particular limitation on the mixing of the bio - based polyether and the Span - based surfactant, and it is only necessary to mix them evenly.

[0046] The fifth object of the present invention is to provide an acrylamide - based polymer emulsion, which is prepared by inverse emulsion synthesis using raw materials including the emulsifier containing bio - based polyether, monomer, initiator, and chelating agent according to any one of the third objects of the present invention to obtain the acrylamide - based polymer emulsion.

[0047] The sixth object of the present invention is to provide a preparation method of an acrylamide - based polymer emulsion, comprising the following steps:

[0048] Form an oil solution by mixing the emulsifier containing bio - based polyether with an organic solvent;

[0049] Mix the vinyl monomer, optionally a sulfonic acid - based monomer, chelating agent, part of the initiator, and water to form an aqueous solution;

[0050] Mix the oil solution and the aqueous solution to form a water - in - oil emulsion;

[0051] After deoxygenating the water - in - oil emulsion, add the remaining initiator to carry out a polymerization reaction to obtain the acrylamide - based polymer emulsion;

[0052] Preferably used for the preparation of the acrylamide polymer emulsion described in the fifth object of the present invention.

[0053] In the preparation method of the acrylamide polymer emulsion described in the present invention, preferably,

[0054] The organic solvent is selected from at least one of white oil and kerosene; and / or,

[0055] The mass ratio of the organic solvent to the bio-based polyether-containing emulsifier is 1:(0.05 - 0.2); and / or,

[0056] The vinyl monomer is selected from at least one of acrylamide, acrylic acid, and N-isopropylacrylamide; and / or,

[0057] The sulfonic acid monomer is selected from at least one of 2-acrylamido-2-methylpropanesulfonic acid and 2-acryloyloxy-2-methylpropanesulfonic acid; and / or,

[0058] The chelating agent is selected from at least one of disodium ethylenediaminetetraacetate and trisodium ethylenediaminetetraacetate; and / or,

[0059] The initiator is selected from at least one of redox initiators (such as ammonium persulfate - sodium bisulfite) and azo initiators (such as VA-044); and / or,

[0060] In the aqueous solution,

[0061] The content of the vinyl monomer is 40 - 50 wt%;

[0062] The content of the sulfonic acid monomer is 0 - 50 wt%;

[0063] The content of the chelating agent is 0.01 - 0.1 wt%;

[0064] The content of the added part of the initiator is 0.01 - 0.1 wt%;

[0065] The mass ratio of the part of the initiator to the remaining initiator is 1 - 4:1;

[0066] The mass ratio of the aqueous solution to the oil solution is (1 - 3):1; and / or,

[0067] The temperature of the polymerization reaction does not exceed 40°C; preferably, the temperature of the polymerization reaction does not exceed 35°C; and / or,

[0068] The time of the polymerization reaction is 2 - 6 h.

[0069] A seventh object of the present invention is to provide an application of an emulsion of an acrylamide polymer as described in the fifth object of the present invention or an emulsion of an acrylamide polymer prepared by the method according to any one of the sixth objects of the present invention in oil exploitation.

[0070] In the present invention, the lignin, catalyst and phenolic modifier can all be obtained commercially.

[0071] In the present invention, the method for adjusting pH is a method commonly used in the art. Preferably, the pH is adjusted by adding an acidic substance or a basic substance. The acidic substance can be at least one of hydrochloric acid, sulfuric acid, acetic acid, and oxalic acid; the basic substance is sodium hydroxide, potassium hydroxide, etc.

[0072] In the present invention, the purification method can be a conventional purification method in the art. For example, the mixture solution obtained after the reaction is centrifuged, then washed repeatedly, and finally dried under vacuum.

[0073] In the ranges disclosed in the present invention, the endpoints and any values are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein. In the following text, in principle, the various technical solutions can be combined with each other to obtain new technical solutions, which should also be regarded as specifically disclosed herein.

[0074] Compared with the prior art, the present invention has the following advantages:

[0075] The present invention provides an emulsifier containing a bio-based polyether, a preparation method and an application thereof. The emulsifier containing a bio-based polyether in the present invention includes a bio-based polyether and a Span surfactant. Among them, the bio-based polyether is obtained by first phenolic-modifying lignin and then alkoxy-modifying it. The inventors of the present invention unexpectedly found in the research that by alkaline phenolic-modifying lignin, the phenolic hydroxyl content of lignin can be greatly increased, the reaction activity of lignin can be greatly improved, the conversion rate of lignin in the subsequent alkoxy-modification can be increased, and the prepared bio-based polyether-containing product is a non-ionic surfactant.

[0076] The present invention also discovers that there is a synergistic effect between the bio-based polyether and a specific Span surfactant when used as an emulsifier, and it has a good emulsifying effect.

[0077] The emulsifier containing a bio-based polyether of the present invention is used in the process of inverse emulsion synthesis of acrylamide polymers, and the obtained emulsion product has the characteristics of low gel content, higher molecular weight, better long-term storage stability, lower residual monomer content, and faster dissolution rate. Detailed implementation manners

[0078] The present invention will be specifically described below in conjunction with specific embodiments. It is necessary to point out here that the following embodiments are only used for further illustration of the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art to the present invention based on the content of the present invention still fall within the protection scope of the present invention.

[0079] In addition, it should be noted that among the various specific technical features described in the following specific implementation manners, they can be combined in any appropriate manner without contradiction. To avoid unnecessary repetition, the present invention will not separately describe various possible combination manners.

[0080] Furthermore, any combination can be made between various different implementation manners of the present invention as long as it does not violate the idea of the present invention. The technical solutions formed thereby belong to a part of the original public content of this specification and also fall within the protection scope of the present invention.

[0081] Source of raw materials:

[0082] Enzymatic lignin was purchased from Shandong Lonli Biological Technology Co., Ltd., and the effective lignin content was 94.8 wt%.

[0083] Alkali lignin was purchased from J&K Scientific Ltd.

[0084] Other raw materials of the present invention are all conventional commercially available products.

[0085] Testing method:

[0086] Molecular weight test:

[0087] The intrinsic viscosity was determined according to the method for determining the intrinsic viscosity of polyacrylamide in GB 12005.1-1989, and the molecular weight was calculated based on the intrinsic viscosity.

[0088] Determination of residual monomer content:

[0089] The residual monomer content was determined according to the method for determining the residual acrylamide content in polyacrylamide in GB 12005.3-1989.

[0090] Testing method for dissolution time:

[0091] The viscosity was measured every minute, and the time when the viscosity reached 80% of the final viscosity was taken as the dissolution time.

[0092] Example 1

[0093] (1) Preparation of highly active lignin: Add 80.2 g of water and 2.4 g of catalyst NaOH into a three-necked flask equipped with a stirrer and a condenser; heat the system to the set temperature of 80 °C, and successively add 13.6 g of enzymatically hydrolyzed lignin and 3.8 g of phenol under stirring, continue stirring, heat and reflux for 1.5 h; after the reaction is completed, add hydrochloric acid to adjust the pH to 3.0 to precipitate the product, and obtain the product highly active lignin (i.e., phenolic lignin) through centrifugal separation, washing, and vacuum drying.

[0094] (2) Preparation of bio-based polyether: Add 26.0 g of highly active lignin into a high-pressure reactor with polytetrafluoroethylene containing 64.6 g of water, stir evenly, and add sodium hydroxide to adjust the pH value of the system to 11.2; heat the system to 63 °C, reduce the pressure to a vacuum degree of -0.15 MPa, add 2.6 g of propylene oxide, stop the reaction after 1 h, cool the system to room temperature, then add hydrochloric acid to adjust the pH of the reaction system to 7.0, and separate, wash, and dry to obtain bio-based polyether.

[0095] (3) Mix 2.4 g of bio-based polyether and 5.6 g of Span 60 evenly to obtain an emulsifying system containing bio-based polyether (i.e., an emulsifier containing bio-based polyether).

[0096] Form an oil solution by mixing 8 g of the emulsifying system containing bio-based polyether with 95 g of white oil; dissolve 80 g of acrylamide and 30 g of 2-acrylamido-2-methylpropanesulfonic acid sodium in 80 g of water, adjust the pH to 7, then add 0.02 g of disodium ethylenediaminetetraacetate, 0.015 g of VA-044, and 0.01 g of ammonium persulfate and dissolve them completely to form an aqueous solution; mix the oil solution and the aqueous solution and emulsify at high speed to form a water-in-oil emulsion; after deoxygenating the water-in-oil emulsion, slowly drop 1 g of 1 wt% sodium bisulfite aqueous solution to carry out a polymerization reaction on the water-in-oil emulsion, control the reaction temperature not to exceed 35 °C, and stop the reaction when the system no longer continues to heat up.

[0097] The gel content of the emulsion product obtained by the above method is 0.5 wt%, the dissolution time is 1 min, it stratifies after storing at room temperature for 180 days, the viscosity-average molecular weight of the polymer is 18.9 million, and the residual monomer content is 0.03 wt%.

[0098] Example 2

[0099] (1) Preparation of highly active lignin: Add 80.2 g of water and 1.8 g of catalyst KOH into a three-necked flask equipped with a stirrer and a condenser; heat the system to the set temperature of 70 °C, and successively add 15 g of alkali lignin and 3.0 g of phenol under stirring, continue stirring, heat and reflux for 0.5 h; after the reaction is completed, add hydrochloric acid to adjust the pH to 2.5 to precipitate the product, and obtain the product highly active lignin through centrifugal separation, washing, and vacuum drying.

[0100] (2) Preparation of bio - based polyether: Add 26.0 g of highly active lignin into a high - pressure reactor with PTFE, which contains 64.6 g of water. Stir evenly, and add sodium hydroxide to adjust the pH value of the system to 11.2. Heat the system to 63 °C, reduce the pressure to a vacuum degree of - 0.15 MPa, add 2.4 g of propylene oxide, stop the reaction after 1 h. After the system cools to room temperature, add hydrochloric acid to adjust the pH to 7.0, and then separate, wash and dry to obtain bio - based polyether.

[0101] (3) Mix 2.4 g of bio - based polyether and 5.6 g of Span 80 evenly to obtain an emulsion system (emulsifier) containing bio - based polyether.

[0102] Use the emulsifier containing bio - based polyether in the process of inverse emulsion synthesis of acrylamide - based polymers by the same method as in Example 1. The gel content of the obtained emulsion product is 0.9 wt%, the dissolution time is 2 min, it stratifies after storing at room temperature for 165 days, the viscosity - average molecular weight of the polymer is 18.1 million, and the residual monomer content is 0.04 wt%.

[0103] Example 3

[0104] (1) Preparation of highly active lignin: Add 80.2 g of water and 2.4 g of catalyst NaOH into a three - necked flask equipped with a stirrer and a condenser. Heat the system to the set temperature of 80 °C, and successively add 13.6 g of enzymatically hydrolyzed lignin and 3.8 g of phenol under stirring. Continue stirring, heat and reflux for 1.5 h. After the reaction ends, add hydrochloric acid to adjust the pH to 3.0 to precipitate the product, and obtain the product highly active lignin through centrifugal separation, washing and vacuum drying.

[0105] (2) Preparation of bio - based polyether: Add 30.0 g of highly active lignin into a high - pressure reactor with PTFE, which contains 63.35 g of water. Stir evenly, and add sodium hydroxide to adjust the pH value of the system to 10.5. Heat the system to 50 °C, reduce the pressure to a vacuum degree of - 0.1 MPa, add 0.15 g of propylene oxide, stop the reaction after 0.5 h. After the system cools to room temperature, adjust the pH to 6.5 by adding hydrochloric acid, and then separate, wash and dry to obtain bio - based polyether.

[0106] (3) Mix 2.4 g of bio - based polyether and 5.6 g of Span 60 evenly to obtain an emulsion system (emulsifier) containing bio - based polyether.

[0107] Using the same method as in Example 1, the emulsifier containing bio-based polyether was used in the process of inverse emulsion synthesis of acrylamide polymers. The gel content of the obtained emulsion product was 1.0 wt%, the dissolution time was 2 min, it stratified after storing at room temperature for 155 days, the viscosity-average molecular weight of the polymer was 16.8 million, and the residual monomer content was 0.06 wt%.

[0108] Example 4

[0109] It used the same preparation method as in Example 1. The difference was that 3.5 g of bio-based polyether and 6.5 g of Span60 were mixed evenly to obtain an emulsifying system containing bio-based polyether.

[0110] The gel content of the emulsion product obtained by the above method was 1.4 wt%, the dissolution time was 3 min, it stratified after storing at room temperature for 150 days, the viscosity-average molecular weight of the polymer was 19.1 million, and the residual monomer content was 0.14 wt%.

[0111] Example 5

[0112] It used the same preparation method as in Example 1. The difference was that 2.5 g of bio-based polyether and 7.5 g of Span60 were mixed evenly to obtain an emulsifying system containing bio-based polyether.

[0113] The gel content of the emulsion product obtained by the above method was 1.1 wt%, the dissolution time was 2 min, it stratified after storing at room temperature for 175 days, the viscosity-average molecular weight of the polymer was 15.6 million, and the residual monomer content was 0.09 wt%.

[0114] Example 6

[0115] It used the same preparation method as in Example 1. The difference was that propylene oxide was replaced with an equal mass of ethylene oxide.

[0116] The gel content of the emulsion product obtained by the above method was 1.5 wt%, the dissolution time was 3 min, it stratified after storing at room temperature for 140 days, the viscosity-average molecular weight of the polymer was 15 million, and the residual monomer content was 0.12 wt%.

[0117] Comparative Example 1

[0118] The experiment was carried out according to the method of Example 1. The difference was that enzymatically hydrolyzed lignin was replaced with sodium lignosulfonate. The gel content of the obtained emulsion product was 6.3 wt%, the dissolution time was 4 min, it stratified after storing at room temperature for 30 days, the viscosity-average molecular weight of the polymer was 13.8 million, and the residual monomer content was 0.55 wt%.

[0119] Comparative Example 2

[0120] The experiment was carried out according to the method of Example 1, except that 3.8 g of phenol was replaced with the same mass of water. The obtained emulsion product had a gel content of 24.0 wt%, a dissolution time of 27 min, delaminated after being stored at room temperature for 6 days, the polymer viscosity-average molecular weight was 14.3 million, and the residual monomer content was 0.46 wt%.

[0121] Comparative Example 3

[0122] The experiment was carried out according to the method of Example 1, except that 2.4 g of bio-based polyether was replaced with the same mass of Tween 80. The obtained emulsion product had a gel content of 3.3 wt%, a dissolution time of 5 min, delaminated after being stored at room temperature for 40 days, the polymer viscosity-average molecular weight was 16.2 million, and the residual monomer content was 0.32 wt%.

[0123] Comparative Example 4

[0124] The experiment was carried out according to the method of Example 1, except that 2.4 g of bio-based polyether was replaced with the same mass of Span 60. The obtained emulsion product had a gel content of 12.3 wt%, a dissolution time of 25 min, delaminated after being stored at room temperature for 10 days, the polymer viscosity-average molecular weight was 10.2 million, and the residual monomer content was 2.9 wt%.

[0125] Comparative Example 5

[0126] The experiment was carried out according to the method of Example 1, except that 5.6 g of Span 60 was replaced with the same mass of bio-based polyether. The obtained emulsion product had a gel content of 54.4 wt%, could not be dissolved, delaminated immediately at room temperature, the polymer viscosity-average molecular weight was 3.2 million, and the residual monomer content was 7.5 wt%.

[0127] Comparative Example 6

[0128] The experiment was carried out according to the method of Example 1, except that bio-based polyether was replaced with phenolic lignin, that is, phenolic lignin in Example 1 and 5.6 g of Span 60 were directly mixed evenly to obtain a composite emulsifier.

[0129] The obtained emulsion product had a gel content of 21.8 wt%, could not be dissolved, delaminated immediately at room temperature, the polymer viscosity-average molecular weight was 5.1 million, and the residual monomer content was 3.08 wt%.

[0130] The present invention has been described in detail above in combination with specific embodiments and exemplary examples, but these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications or improvements can be made to the technical solutions of the present invention and their implementation manners, and these all fall within the scope of the present invention. The protection scope of the present invention is subject to the appended claims.

[0131] All publications, patent applications, patents, and other references mentioned in this specification are hereby incorporated by reference in their entirety. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by one of ordinary skill in the art. In case of conflict, the definitions in this specification shall prevail.

[0132] When this specification uses the prefixes "well-known to those skilled in the art", "prior art", or similar terms to introduce materials, substances, methods, steps, devices, or components, etc., the objects introduced by such prefixes cover those commonly used in the art at the time this application is filed, but also include those that are not commonly used at present but will become recognized in the art as suitable for similar purposes.

[0133] In the context of this specification, any matter or thing not mentioned, other than what is expressly stated, shall directly apply those known in the art without any change.

Claims

1. A bio-based polyether, characterized in that: The bio-based polyether is prepared by reacting raw materials including phenolic lignin and epoxide; wherein, the phenolic lignin is selected from alkali-catalyzed modified phenolic lignin.

2. A preparation method of a bio-based polyether, characterized in that, It includes the following steps: Add phenolic lignin into water, adjust the pH, wait until the phenolic lignin is completely dissolved, then add epoxide for heating reaction to obtain the bio-based polyether; wherein, the phenolic lignin is selected from alkali-catalyzed modified phenolic lignin; Preferably used for the preparation of the bio-based polyether described in claim 1.

3. The preparation method of the bio-based polyether according to claim 2, characterized in that: The epoxide is selected from at least one of ethylene oxide and propylene oxide; and / or, Adjust the pH value to 10.5 - 11.5; and / or, Based on the total mass of phenolic lignin, epoxide, and water added in this step being 100%, The addition amount of phenolic lignin is 15wt% - 30wt%; The addition amount of epoxide is 0.15wt% - 3wt%; The temperature of the heating reaction is 50 - 65°C; and / or, The time of the heating reaction is 0.5 - 1.5h; and / or, The pressure of the heating reaction is (-0.1) - (-0.2)MPa.

4. The preparation method of the bio-based polyether according to claim 2, characterized in that: The preparation method of phenolic lignin includes: Under closed conditions, contact reaction of raw materials including lignin, phenolic modifier, and alkaline catalyst in water, and optionally adjust the pH to obtain phenolic lignin; Preferably, The lignin is selected from at least one of alkali lignin and enzymatically hydrolyzed lignin; and / or, The phenolic modifier is selected from at least one of phenol and hydroquinone; and / or, The alkaline catalyst is selected from at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, sodium bicarbonate, and ammonia water; and / or, Based on the total mass of lignin, phenolic modifier, alkaline catalyst, and water added in this step being 100%, The addition amount of lignin is 10 - 15wt%; The mass ratio of the phenolic modifier to the lignin is 0.2 - 0.4:1; The mass ratio of the alkaline catalyst to the lignin is 0.12 - 0.3:1; and / or, The temperature of the contact reaction is 70 - 85°C; and / or, The contact reaction time is 0.5 - 2h; and / or, Adjust the pH = 2 - 3.

5. An emulsifier containing bio-based polyether, characterized in that: The emulsifier includes span and bio-based polyether; The bio-based polyether is selected from the bio-based polyether described in claim 1 or the bio-based polyether prepared by the method described in any one of claims 2 - 4.

6. The emulsifier containing bio-based polyether according to claim 5, characterized in that: In the emulsifier, The content of span is 60 - 85wt%; The content of bio-based polyether is 15 - 40wt%; Preferably, The content of span is 65 - 75wt%; The content of bio-based polyether is 25 - 35wt%.

7. The emulsifier containing bio-based polyether according to claim 5, characterized in that, The span is selected from at least one of span 60, span 80, and span 83.

8. A method for preparing an emulsifier containing a bio-based polyether according to any one of claims 5-7, characterized in that, It includes the following steps: Mix sorbitan and bio-based polyether evenly to obtain the emulsifier.

9. An emulsion of an acrylamide polymer, characterized in that, Use the raw materials including the emulsifier containing bio-based polyether, monomer, initiator, and chelating agent described in any one of claims 5-7 to carry out inverse emulsion synthesis to obtain an acrylamide polymer emulsion.

10. A method for preparing an acrylamide polymer emulsion, characterized in that: Form an oil solution by mixing the emulsifier containing bio-based polyether with an organic solvent; Mix a vinyl monomer, optionally a sulfonic acid monomer, a chelating agent, a part of the initiator, and water to form an aqueous solution; Mix the oil solution and the aqueous solution to form a water-in-oil emulsion; After deoxygenating the water-in-oil emulsion, add the remaining initiator to carry out a polymerization reaction to obtain an acrylamide polymer emulsion; Preferably used for the preparation of the acrylamide polymer emulsion described in claim 9.

11. According to the method for preparing an acrylamide polymer emulsion described in claim 10, characterized in that: The organic solvent is selected from at least one of white oil and kerosene; and / or, The mass ratio of the organic solvent to the emulsifier containing bio-based polyether is 1:(0.05-0.2); and / or, The vinyl monomer is selected from at least one of acrylamide, acrylic acid, and N-isopropylacrylamide; and / or, The sulfonic acid monomer is selected from at least one of 2-acrylamido-2-methylpropanesulfonic acid and 2-acryloyloxy-2-methylpropanesulfonic acid; and / or, The chelating agent is selected from at least one of disodium ethylenediaminetetraacetate and trisodium ethylenediaminetetraacetate; and / or, The initiator is selected from at least one of redox initiators and azo initiators; and / or, In the aqueous solution, The content of the vinyl monomer is 40-50 wt%; The content of the sulfonic acid monomer is 0-50 wt%; The content of the chelating agent is 0.01-0.1 wt%; The content of the part of the initiator added is 0.01-0.1 wt%; The mass ratio of the part of the initiator to the remaining initiator is 1-4:1; The mass ratio of the aqueous solution to the oil solution is (1-3):1; and / or, The temperature of the polymerization reaction does not exceed 40°C; preferably, the temperature of the polymerization reaction does not exceed 35°C; and / or, The time of the polymerization reaction is 2-6 h.

12. Application of the acrylamide polymer emulsion described in claim 9 or the acrylamide polymer emulsion prepared by the method described in any one of claims 10-11 in oil exploitation.