A polymer with high-efficiency and long-acting emulsified water demulsification coalescence function and a preparation method and application thereof

Abstract

The application discloses a polymer with high-efficiency and long-acting emulsified water demulsification and coalescence functions and a preparation method and application thereof. The polymer is prepared from the following components in parts by mass: 100 parts of monomers, 1-4 parts of an initiator, 2-6 parts of a surfactant and 300-600 parts of water; the monomers are composed of the following components in parts by mass: 15-30 parts of acrylic ester zwitterionic monomers, 3-7 parts of crosslinking monomers, 10-20 parts of vinyl polyether monomers and 43-72 parts of other acrylic ester monomers; and the surfactant is a mixture of zwitterionic surfactants and polyvinyl alcohol. The polymer can be applied to surface coating modification of various porous filter materials, can make emulsified water droplets collide with the surface during flowing through the inside of the porous filter material, and can instantaneously demulsify and coalesce to form large water droplets to realize separation, and has a wide application prospect in the field of emulsified water coalescence and separation in fuel oil.

Description

Technical Field

[0001] This invention belongs to the technical field of polymer materials and filtration materials, specifically relating to a polymer with efficient and long-lasting emulsification and demulsification functions, its preparation method, and its application. Background Technology

[0002] Water contamination in fuels such as diesel or aviation kerosene is a crucial indicator of fuel quality and a major cause of engine malfunctions. Water contamination in fuel can decompose certain additives in the fuel, forming acids that corrode the engine's fuel injection system and the engine itself. Simultaneously, the presence of water contamination accelerates fuel oxidation, generating viscous sludge that easily clogs microporous components such as nozzles and filters. Furthermore, at low temperatures, water contamination in fuel can freeze and block engine fuel lines, affecting fuel supply; water in the fuel also reduces its calorific value, leading to increased emissions of pollutants. Therefore, separating water from fuel is essential. However, with the development of ultra-low sulfur fuels and biofuels, the content of surfactants added to fuels is constantly increasing to ensure sufficient lubricity. These added surfactants not only adsorb at the oil-water interface, reducing the interfacial tension (IFT) and decreasing the size and stability of water droplets in diesel fuel, but also increase the difficulty of oil-water separation. Even more seriously, the surfactants in the oil can be adsorbed onto the surface of the filter media, causing changes in the wettability of the filter media, thereby affecting the stability of the oil-water separation efficiency of the filter media and leading to a sharp decline in the oil-water separation performance of the material.

[0003] Our research team previously (Chinese Patent CN 110330586 B) prepared polymers with amphiphilic molecular segments on their surfaces to create coalescing materials, demonstrating excellent demulsification and coalescence capabilities for emulsions containing nonionic surfactants in oils. However, in reality, fuels contain a wide variety of additives, including not only nonionic additives but also many cationic and anionic additives. Different ionic properties of additives require different surface properties to demulsify and coalesce the resulting emulsions, thus posing a greater challenge to the surface design of fuel oil-water separation materials. Existing technology (Jing Yang et al., Janus membranes with controllable asymmetric configurations for highly efficient separation of oil-in-water emulsions.) reported two types of microfiltration membranes: a positively charged polydopamine / polydiallyldimethylammonium chloride deposited polypropylene microfiltration membrane and a negatively charged polydopamine / sodium polystyrene sulfonate deposited polypropylene microfiltration membrane. These two membranes can be used to separate emulsions stabilized by anionic and cationic surfactants, respectively. This demonstrates the effectiveness of this method based on electrostatic demulsification through the interaction between different charges. Chinese patent [CN 114225563B] describes a method for obtaining Janus stainless steel mesh with asymmetric charge properties by brushing a first and second viscous solution onto both sides of a stainless steel mesh that has been immersed in a dopamine solution containing a buffer solvent, followed by a series of post-treatments. This method achieves efficient demulsification by simultaneously separating emulsions stabilized by anionic / cationic surfactants, with one side exhibiting a positive charge and the other a negative charge. However, the reported method requires the preparation of different charged brushing liquid materials, special selection and treatment of the substrate, and complex and refined processes to achieve the asymmetric charge properties of the material, resulting in poor general applicability. Summary of the Invention

[0004] To address the shortcomings and deficiencies of existing technologies, the main objective of this invention is to provide a polymer with efficient and long-lasting emulsion demulsification and coalescence functions, along with its preparation method and applications. This polymer surface can not only produce efficient and long-lasting demulsification and coalescence effects on emulsions in the presence of surfactants with different ionic properties, but also, after a simple surface treatment agent drying process using this polymer emulsion on a porous coalescing substrate, achieve efficient and long-lasting oil-water separation performance for emulsions containing different surface charge properties.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A polymer with efficient and long-lasting emulsifying and demulsifying coalescence function is prepared from the following components by mass: 100 parts monomer, 1-4 parts initiator, 2-6 parts surfactant and 300-600 parts water.

[0007] By mass fraction, the monomer consists of the following components: 15-30 parts of acrylate zwitterionic monomer, 3-7 parts of crosslinking monomer, 10-20 parts of vinyl polyether monomer, and 43-72 parts of other acrylate monomers.

[0008] The structure of the acrylate zwitterionic monomer is as follows:

[0009]

[0010] Where a = 2 - 4, b = 2 - 6, X = COO - or SO3 - ;

[0011] The structure of the vinyl polyether monomer is as follows:

[0012]

[0013] Where n = 2 - 4, m = 3 - 8;

[0014] The surfactant is a mixture of amphoteric surfactant and polyvinyl alcohol.

[0015] Preferably, the polymer with efficient and long-lasting emulsifying water demulsification and polymerization function is prepared from the following components by mass: 100 parts of monomer, 2-3 parts of initiator, 2-4 parts of surfactant and 400-500 parts of solvent.

[0016] Preferably, the monomer is composed of the following components by mass: 15-25 parts of zwitterionic acrylate monomer, 3-5 parts of crosslinking monomer, 15-20 parts of vinyl polyether monomer, and 50-70 parts of other common acrylate monomers.

[0017] Preferably, in the zwitterionic monomer of the acrylate, b is 4 to 6;

[0018] Preferably, in the vinyl polyether monomer, m is 4 to 6;

[0019] Preferably, the crosslinking monomer is a mixture of polyethylene crosslinking monomer and self-crosslinking monomer, with a mass ratio of 1:1 to 1:4.

[0020] More preferably, the polyethylene crosslinking monomer is selected from at least one of divinylbenzene and ethylene glycol dimethacrylate;

[0021] More preferably, the self-crosslinking monomer is selected from at least one of vinyltrimethoxysilane and N-hydroxyethylacrylamide.

[0022] Preferably, the other acrylate monomers are selected from at least one of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, dodecyl acrylate, methyl methacrylate, ethyl methacrylate, and tert-butyl methacrylate;

[0023] More preferably, the other acrylate monomers are selected from at least one of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, dodecyl acrylate, and at least one of methyl methacrylate, ethyl methacrylate, and tert-butyl methacrylate.

[0024] Preferably, the degree of polymerization of the polyvinyl alcohol is 1500-1900, and the degree of alcoholysis is ≥80%.

[0025] Preferably, the mass ratio of the zwitterionic surfactant to polyvinyl alcohol is 2:1-4:1;

[0026] More preferably, the mass ratio of the zwitterionic surfactant to polyvinyl alcohol is 2:1-3:1.

[0027] Preferably, the zwitterionic surfactant is selected from at least one of dodecyl dimethyl betaine, sodium dodecyl aspartate, and dodecyl hydroxyethyl imidazoline;

[0028] Preferably, the initiator is selected from at least one of azobisisobutyronitrile, azobisisoheptanenitrile, and azoisobutylcyanoformamide.

[0029] The preparation method of the polymer with high efficiency and long-lasting emulsification and demulsification function includes the following steps:

[0030] The monomer, initiator, surfactant and water are mixed and reacted at 70-80℃ for 2-8 hours to obtain a polymer with efficient and long-lasting emulsification and demulsification function.

[0031] Preferably, the preparation method of the polymer with efficient and long-lasting emulsifying and demulsifying coalescence functions specifically includes the following steps:

[0032] (1) Add 1 / 3 to 1 / 2 of the surfactant (1 / 3 to 1 / 2 each of zwitterionic surfactant and polyvinyl alcohol) to 100 to 150 parts of water, heat and stir until completely dissolved, then cool to room temperature, add acrylate zwitterionic monomer to form a pre-emulsion; then mix crosslinking monomer, vinyl polyether monomer, other acrylate monomers and initiator to form a monomer mixture, add the monomer mixture to the pre-emulsion while stirring at 800 to 1000 rpm, and then continue emulsifying at 5000 to 8000 rpm for 0.5 to 1.0 h to form a monomer emulsion;

[0033] (2) Add the remaining surfactant and water to the reactor, then add 1 / 4 to 1 / 3 of the monomer emulsion from step (1), heat to 70 to 80°C, and keep the reaction at this temperature for 1.0 to 2 hours.

[0034] (3) Continue to add the remaining monomer emulsion from step (1) to the reactor dropwise over 2 to 3 hours, and then continue to keep the reaction at the temperature for 2 to 3 hours.

[0035] (4) Cool down to 40-50℃ and discharge the material to obtain a polymer emulsion with efficient and long-lasting emulsification and demulsification functions.

[0036] A coalescing filter material with efficient and long-lasting emulsified water demulsification and coalescence function comprises the above-mentioned polymer with efficient and long-lasting emulsified water demulsification and coalescence function and a porous substrate, wherein the polymer with efficient and long-lasting emulsified water demulsification and coalescence function is attached to the porous substrate.

[0037] The preparation method of the above-mentioned coalescing filter material with efficient and long-lasting emulsification and coalescence functions includes the following steps:

[0038] A porous substrate is impregnated in a polymer emulsion with efficient and long-lasting emulsification and coalescence functions, and then removed, dried and cured to obtain a coalesced filter material with efficient and long-lasting emulsification and coalescence functions.

[0039] Preferably, the concentration of the polymer emulsion with efficient and long-lasting emulsifying and demulsifying coalescence function is 1-3 wt%.

[0040] The above-mentioned polymers with efficient and long-lasting emulsification and coalescence functions, or the above-mentioned coalescing filter media with efficient and long-lasting emulsification and coalescence functions, are used in oil-water separation.

[0041] Preferably, the oil-water contains at least one of a nonionic surfactant, anionic surfactant, and cationic surfactant.

[0042] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0043] The polymer described in this invention, possessing efficient and long-lasting emulsion demulsification and coalescence functions, incorporates acrylate zwitterionic monomers and vinyl polyether monomers, resulting in side chains containing both anionic and cationic end groups and polyether groups. Therefore, it exhibits highly efficient demulsification and coalescence effects on emulsions containing anionic, cationic, or nonionic surfactants. Furthermore, the solvation and hydrogen bonding effects of the charged end functional groups of the zwitterionic groups enable the formation of a hydration layer on the surface of the zwitterionic polymer. This electrostatically formed hydration layer effectively prevents oil molecules from adsorbing onto the material surface, thus preventing the degradation of the interaction between the material surface and emulsion droplets, resulting in long-lasting water separation performance. Moreover, the polymer described in this invention has a wide range of applications; it can be applied to various porous coalescing substrates through simple processes such as impregnation or coating, and exhibits excellent oil-water separation performance for fuels containing surfactants with different charge properties.

[0044] Although the vinyl polyether used in this invention differs only slightly in structure from the amphiphilic monomer structure used in the previously filed patent [CN110330586B], it is indeed this vinyl polyether monomer used in this invention that allows for better free radical copolymerization with the other monomer components of this invention. The conversion rate of the polymer obtained by copolymerization using the vinyl polyether monomer of this invention is higher than 95%, while the conversion rate of the monomer using the structure of patent CN110330586B is lower than 85%. The conversion rate of the prepared product is also the reason why this invention specifically emphasizes the use of the vinyl polyether with this particular structure. In addition, many studies have reported the preparation of underwater superhydrophilic and oleophobic materials using zwitterionic polymers for the separation of oil in water. This invention, by controlling the structure of the zwitterionic monomer and its proportion in the polymer, and combining the effect of the hydrophilic polyether monomer, maintains the excellent amphiphilic properties of the material surface, making it suitable for the separation of water coalescence in fuel oil. This is also a unique feature of this invention's use of zwitterionic polymers. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of a test method for the coalescence and separation of emulsified water in oil.

[0046] Figure 2 This is a SEM image of the glass fiber coalescing substrate used in this invention.

[0047] Figure 3 SEM image of the polymer prepared in Example 1 after treating the glass fiber coalesced substrate (Example 4).

[0048] Figure 4SEM image of the polymer-treated glass fiber polymer substrate prepared in Example 2 (Example 5). Detailed Implementation

[0049] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0050] Unless otherwise specified, the experimental methods described in the embodiments of this invention are all conventional methods; the raw materials and reagents used in the embodiments can be obtained commercially unless otherwise specified.

[0051] The structural formulas of the acrylate zwitterionic monomers used in the examples are as follows:

[0052]

[0053] Where a = 2 - 4, b = 2 - 6, X = COO - or SO3 - ;

[0054] The structural formula of the vinyl polyether monomer is as follows:

[0055]

[0056] Where n = 2 - 4, m = 3 - 8.

[0057] Example 1

[0058] A polymer with efficient and long-lasting emulsifying and demulsifying properties was prepared according to the following formulation and the following steps:

[0059] (1) Add 1.5g dodecyl dimethyl betaine and 0.6g polyvinyl alcohol (degree of polymerization 1700, degree of alcoholysis 88%) to 100g water, heat and stir until completely dissolved, then cool to room temperature, and add acrylate zwitterionic monomer (where a=2, b=6, X=COO). - 18.0g was used to form a pre-emulsion. Then, a monomer mixture was added under high-speed stirring (800rpm). The monomer mixture specifically included 20.0g of vinyl polyether monomer (n=2, b=4), 1.0g of crosslinking monomer divinylbenzene, 3.0g of N-hydroxyethyl acrylamide, 30.0g of methyl methacrylate, 28.0g of butyl acrylate, and 1.5g of azobisisobutyronitrile. Then, high-speed emulsification (5000rpm) was continued for 0.5h to form a stable monomer emulsion.

[0060] (2) Add the remaining 1.5g dodecyl dimethyl betaine and 0.6g polyvinyl alcohol to 400g water and mix them evenly. Then add 1 / 3 of the monomer emulsion from step (1), heat to 75°C, and keep the reaction at this temperature for about 1 hour.

[0061] (3) Continue to add the remaining monomer emulsion from step (1) to the reactor, and finish adding it over 2 hours. Continue to keep the reactor warm for 3 hours.

[0062] (4) Cool down to 40-50℃ and discharge the material to obtain a polymer emulsion with efficient and long-lasting emulsification and demulsification functions. The product is white, has no obvious monomer odor, has a monomer conversion rate of 97.42 wt%, a gelation rate of only 1.17 wt%, and is stable after three months of storage.

[0063] Example 2

[0064] A polymer with efficient and long-lasting emulsifying and demulsifying properties was prepared according to the following formulation and the following steps:

[0065] (1) Add 1.8g of sodium dodecyl aspartate and 0.8g of polyvinyl alcohol (with a degree of polymerization of 1700 and a degree of alcoholysis of 99%) to 120g of water, heat and stir until completely dissolved, then cool to room temperature, and add zwitterionic acrylate monomers (where a=2, b=4, X=SO3). - 20.0g of pre-emulsion was formed, and then a monomer mixture was added under high-speed stirring (1000rpm). The monomer mixture specifically included 15.0g of vinyl polyether monomer (n=2, m=6), 1.5g of divinylbenzene, 3.5g of N-hydroxyethyl acrylamide, 30.0g of methyl acrylate, 30.0g of butyl methacrylate, and 2.0g of initiator azobisisobutyronitrile. Then, high-speed emulsification (5000rpm) was continued for 0.5h to form a stable monomer emulsion.

[0066] (2) Add the remaining 1.8g sodium dodecyl aspartate and 0.8g polyvinyl alcohol to 450g water and mix them evenly in the reaction vessel. Then add 1 / 3 of the monomer emulsion from step (1), heat to 75°C, and keep the reaction at this temperature for about 1 hour.

[0067] (3) Continue to add the remaining monomer emulsion from step (1) to the reactor, and finish adding it over 2 hours. Continue to keep the reactor warm for 3 hours.

[0068] (4) Cool down to 45°C and discharge the material to obtain a polymer emulsion with efficient and long-lasting emulsification and demulsification functions. The product is white, has no obvious monomer odor, has a monomer conversion rate of 97.11 wt%, and a gelation rate of only 1.21 wt%. It is stable after three months of storage.

[0069] Example 3

[0070] A polymer with efficient and long-lasting emulsifying and demulsifying properties was prepared according to the following formulation and the following steps:

[0071] (1) Add 2.0 g of emulsifier dodecyl hydroxyethyl imidazoline and 0.8 g of polyvinyl alcohol (with a degree of polymerization of 1800 and a degree of alcoholysis of 88%) to 100 g of water, heat and stir until completely dissolved, then cool to room temperature, and add acrylate zwitterionic monomer (a = 4, m = 4, X = SO3). - 25.0g of pre-emulsion was formed, and then the remaining monomer mixture was added under high-speed stirring (800rpm). The monomer mixture specifically included 10.0g of vinyl polyether monomer (n=2, m=4), 2.0g of divinylbenzene and 2.0g of N-hydroxyethyl acrylamide, 20.0g of ethyl acrylate, 41.0g of butyl acrylate and 2.8g of initiator azobisisobutyronitrile. Then, high-speed emulsification (8000rpm) was continued for 0.5h to form a stable monomer emulsion.

[0072] (2) Add the remaining 2.0g of dodecyl hydroxyethyl imidazoline and 0.80g of polyvinyl alcohol to 400g of water into the reactor and mix evenly. Then add 1 / 3 of the monomer emulsion from step (1), heat to 75°C, and keep warm for about 1 hour.

[0073] (3) Continue to add the remaining monomer emulsion from step (1) to the reactor, and finish adding it over 2 hours. Continue to keep the reactor warm for 3 hours.

[0074] (4) Cool down to 40℃ and discharge the material to obtain a polymer emulsion with efficient and long-lasting emulsification and demulsification functions. The product is white, has no obvious monomer odor, has a gelation rate of only 1.33wt%, a monomer conversion rate of 96.94wt%, and is stable after three months of storage.

[0075] Comparative Example 1

[0076] The process formulation of Comparative Example 1 was basically the same as that of Example 1, except that no acrylate zwitterionic monomer was added to the system. The final product was a white emulsion with no obvious monomer odor, a gelation rate of only 1.23 wt%, a monomer conversion rate of 97.5 wt%, and was stable after three months of storage.

[0077] Comparative Example 2

[0078] The process formulation of Comparative Example 2 was basically the same as that of Example 1, except that the mixed monomer composition used did not contain vinyl polyether monomers. The final product was a white emulsion with no obvious monomer odor, a monomer conversion rate of 96.78 wt%, a gelation rate of only 2.17 wt%, and was stable after three months of storage.

[0079] Comparative Example 3

[0080] The process formulation of Comparative Example 3 is basically the same as that of Example 1, but the polymer system does not contain acrylate zwitterionic monomers or vinyl polyether monomers. It is a common acrylic emulsion. The final product is a white emulsion with no obvious monomer odor. The monomer conversion rate is 97.25 wt%, and its gelation rate is only 1.25 wt%. It is stable after being stored for three months.

[0081] Comparative Example 4

[0082] The process formulation of Comparative Example 4 was basically the same as that of Example 3, except that the amount of zwitterionic acrylate monomer in the mixed monomer composition was increased from 25.0 g to 38.0 g, and the amount of other acrylate monomers was correspondingly reduced (specifically: 10.0 g of vinyl polyether monomer (n=2, m=4), 2.0 g of divinylbenzene and 2.0 g of N-hydroxyethylacrylamide, 15.0 g of ethyl acrylate, and 33.0 g of butyl acrylate). The final product was a white viscous emulsion with no obvious monomer odor. The monomer conversion rate was 95.84 wt%. It gelled after 2 days and was unusable.

[0083] Comparative Example 5

[0084] The process formulation of Comparative Example 5 was basically the same as that of Example 1, except that the emulsifier used did not contain polyvinyl alcohol. During the polymerization process, the emulsion separated into layers, and the resulting product had a gelation rate as high as 10.33 wt% and a noticeable monomer odor. The monomer conversion rate was 79.4 wt%, and obvious precipitation could be observed after 3 days, rendering it unusable.

[0085] Comparative Example 6

[0086] The process formulation of Comparative Example 6 was basically the same as that of Example 1, except that the vinyl polyether monomer used in the system was the polyether monomer (polyethylene glycol (400) monoester of methacrylate) described in patent CN 114225563B. The final product was a white emulsion with a noticeable monomer odor. The total monomer conversion rate was only 81.20 wt%. After being left for one week, it separated into layers and could not be used.

[0087] Examples 4-6 and Comparative Examples 7-9

[0088] The fabrication of fiberglass base paper: 475-79 glass wool and chopped glass fibers are mixed in a 7:3 mass ratio and then loosened using a delamination machine at 10,000 revolutions. The pH is controlled at 2.5-3.5, and the basis weight is 48±1 g / m³. 2 After the slurry is evenly dispersed, it is poured into the forming machine, dehydrated and formed, and then dried on a flat plate to obtain the fiberglass substrate.

[0089] After diluting the emulsions prepared in Examples 1-3 and the polymer emulsions prepared in Comparative Examples 1-3 to a suitable concentration (1.5 wt%), the glass fiber substrate was immersed in the diluted polymer emulsion, removed, dried and cured, and the amount of polymer coating was controlled within the range of 5.0 ± 0.5% to obtain the coalesced filter materials of Examples 4-6 and Comparative Examples 7-9.

[0090] The water separation performance of Examples 4-6 and Comparative Examples 7-9 was tested using the water separation test methods described below.

[0091] Water separation test method: Use the oil-water separation test bench shown in the diagram (e.g., Figure 1 (As shown) The water separation performance of the treated glass fiber filter media was tested. First, different types of surfactants were dissolved in a metered oil-water mixture (oil-water mass ratio of 90:10, oil being diesel). The nonionic surfactant used in this experiment was Span 80, the anionic surfactant was sodium dodecyl sulfate (SDS), and the cationic surfactant was dodecyltrimethylammonium chloride (CTAC). The amount of surfactant added was 0.3 wt% of the oil-water mixture (or 0.3 wt% if two surfactants were used). The mixture was emulsified using a high-speed disperser at 5000 rpm to obtain an oil-water emulsion. After the filter media sample was placed in a fixture, the emulsion was pumped through the sample at a set flow rate. Samples taken from the upstream and downstream sampling ports were tested for water content using a Karl Fischer moisture analyzer (C20 model, METTLER TOLEDO, Switzerland). Sampling and measurement were performed every 15 minutes. The test was terminated after 1 hour. The average of several sampling tests was the total water content of the upstream and downstream ports. The water separation efficiency was calculated using the formula: Emulsion water separation efficiency % = (Upstream water content - Downstream water content) / (Upstream water content * 100%). The water separation test results are shown in Table 1 below.

[0092] Table 1 Performance test results of each embodiment and comparative example

[0093]

[0094]

[0095] As can be seen from the water separation test data in Table 1, the polymers with efficient and long-lasting emulsifying and demulsifying coalescing functions prepared in Examples 1-3 of this invention, when applied to glass fiber coalescing substrates (Examples 4-6), enable the modified glass fiber coalescing materials to efficiently demulsify and coalesce emulsified water droplets in oil-water mixtures after emulsification by different ionic emulsifier systems, thereby achieving efficient water separation. Furthermore, from... Figures 2 to 4The microstructure of the glass fiber substrate and the modified glass fiber coalesced filter material shows that after polymer impregnation modification, the glass fiber substrate does not have obvious pore blockage and still maintains the good porous structure of the filter material.

[0096] The polymer prepared in Comparative Example 3 contains neither acrylate zwitterionic monomers nor polyether monomers, and its oil-water separation performance after emulsification with emulsifiers of different properties is very poor (Comparative Example 9). The polymer prepared in Comparative Example 1 contains vinyl polyether monomers but does not contain acrylate zwitterionic monomers. Therefore, when this polymer is applied to glass fiber coalescing filter media (Comparative Example 7), its oil-water separation performance after emulsification with different emulsifier systems is poor, especially in systems containing ionic surfactants. The polymer prepared in Comparative Example 2 contains acrylate zwitterionic monomers but does not contain vinyl polyether monomers. Therefore, when this polymer is applied to glass fiber coalescing filter media (Comparative Example 8), its oil-water separation performance after emulsification with different emulsifier systems is poor, especially in systems containing nonionic emulsifiers. Comparing the above test results, it is evident that the presence of acrylate zwitterionic monomers and vinyl polyether monomers in the polymer system plays a crucial role in the efficient separation of emulsified water in oil-water mixtures. The introduction of acrylate zwitterionic monomers in this invention not only improves the demulsification effect on systems containing ionic surfactants but also on systems containing nonionic emulsifiers. Similarly, the introduction of vinyl polyether monomers improves the demulsification effect on systems containing ionic surfactants, demonstrating a synergistic effect of acrylate zwitterionic monomers and vinyl polyether monomers in the polymer system of this invention. Furthermore, Comparative Example 6 used polyether monomers with other structures. The results showed poor compatibility between these monomers and other monomers in the polymer system, resulting in a monomer conversion rate of only 81.2%, high monomer residue, strong odor, and unstable product, failing to meet practical application requirements.

[0097] After the coalescing materials of Examples 4-6 were subjected to water separation tests, they were continuously immersed in the oil-water mixture in the test system for 3 days. The water separation performance was then tested again using the same method. The test results are shown in Table 2.

[0098] Table 2. Changes in water separation performance after immersion treatment in each example.

[0099]

[0100] As can be seen from the water separation test data in Table 2, the polymers with high efficiency and long-lasting emulsification and demulsification coalescence functions prepared by Examples 1-3 of the present invention, when applied to glass fiber coalescing substrates (Examples 4-6), after prolonged immersion in oil-water mixtures, still maintain high water separation efficiency. This indicates that the water separation material prepared by the present invention not only has high efficiency but also excellent long-lasting properties.

Claims

1. A polymer with efficient and long-lasting emulsifying, demulsifying, and coalescing functions, characterized in that, It is prepared from the following components by mass: 100 parts monomer, 1-4 parts initiator, 2-6 parts surfactant and 300-600 parts water; By mass fraction, the monomer consists of the following components: 15-30 parts of acrylate zwitterionic monomer, 3-7 parts of crosslinking monomer, 10-20 parts of vinyl polyether monomer, and 43-72 parts of other acrylate monomers. The structure of the acrylate zwitterionic monomer is as follows: Where a = 2 - 4, b = 2 - 6, X = COO - or SO3 - ; The structure of the vinyl polyether monomer is as follows: Where n = 2 - 4, m = 3 - 8; The surfactant is a mixture of amphoteric surfactant and polyvinyl alcohol; The preparation method of the polymer with efficient and long-lasting emulsifying and demulsifying coalescence functions specifically includes the following steps: (1) Add 1 / 3 to 1 / 2 of the surfactant to 100 to 150 parts of water, heat and stir until completely dissolved, then cool to room temperature, add acrylate zwitterionic monomer to form a pre-emulsion; then mix the crosslinking monomer, vinyl polyether monomer, other acrylate monomers and initiator to form a monomer mixture, add the monomer mixture to the pre-emulsion while stirring at 800 to 1000 rpm, and then continue emulsifying at 5000 to 8000 rpm for 0.5 to 1.0 h to form a monomer emulsion; (2) Add the remaining surfactant and the remaining water to the reactor, then add 1 / 4 to 1 / 3 of the monomer emulsion from step (1), heat to 70 to 80°C, and keep the reaction at this temperature for 1.0 to 2 hours. (3) Continue to add the remaining monomer emulsion from step (1) to the reactor, and finish adding it over 2 to 3 hours. Then continue to keep the reactor warm for 2 to 3 hours. (4) Cool down to 40~50℃, discharge the material, and obtain a polymer emulsion with efficient and long-lasting emulsification and demulsification functions.

2. The polymer with efficient and long-lasting emulsifying and demulsifying coalescence function according to claim 1, characterized in that, The crosslinking monomer is a mixture of polyethylene crosslinking monomer and self-crosslinking monomer, with a mass ratio of 1:1 to 1:

4.

3. The polymer with efficient and long-lasting emulsifying and demulsifying coalescence function according to claim 2, characterized in that, The polyethylene crosslinking monomer is selected from at least one of divinylbenzene and ethylene glycol dimethacrylate; The self-crosslinking monomer is selected from at least one of vinyltrimethoxysilane and N-hydroxyethylacrylamide.

4. The polymer with efficient and long-lasting emulsifying and demulsifying coalescence function according to claim 1, characterized in that, The other acrylate monomers are selected from at least one of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, dodecyl acrylate, methyl methacrylate, ethyl methacrylate, and tert-butyl methacrylate. The degree of polymerization of the polyvinyl alcohol is 1500-1900, and the degree of alcoholysis is ≥80%. The mass ratio of the zwitterionic surfactant to polyvinyl alcohol is 2:1-4:1; The zwitterionic surfactant is selected from at least one of dodecyl dimethyl betaine, sodium dodecyl aspartate and dodecyl hydroxyethyl imidazoline; The initiator is selected from at least one of azobisisobutyronitrile, azobisisoheptanenitrile, and azoisobutylcyanoformamide.

5. A coalescing filter material with efficient and long-lasting emulsification and coalescence demulsification functions, characterized in that, The invention comprises the polymer and porous substrate having efficient and long-lasting emulsified water demulsification and coalescence function as described in any one of claims 1-4, wherein the polymer having efficient and long-lasting emulsified water demulsification and coalescence function is attached to the porous substrate.

6. The method for preparing the coalescing filter material with efficient and long-lasting emulsification and coalescence functions as described in claim 5, characterized in that, Includes the following steps: A porous substrate is impregnated in a polymer emulsion with efficient and long-lasting emulsification and coalescence functions, and then removed, dried and cured to obtain a coalesced filter material with efficient and long-lasting emulsification and coalescence functions.

7. The application of the polymer with efficient and long-lasting emulsifying and demulsifying coalescence function as described in any one of claims 1-4 in oil-water separation.

8. The application according to claim 7, characterized in that, The oil-water mixture contains at least one of nonionic surfactants, anionic surfactants, and cationic surfactants.

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