Batch production method of a series of melamine-based porous polymers and applications thereof

Abstract

The application discloses a preparation method for preparing a series of porous polymer microspheres (nanometer size) in a one-pot method with melamine as a basic monomer, and explores potential application fields of the series of polymers. The application mainly synthesizes three types of porous polymers, i.e. polyurea, polyimide and amino-aldehyde polymer, based on melamine, and all of the three types of porous polymers are formed by first emulsifying and polymerizing to form spherical colloidal particles, and then further crosslinking and polymerizing to form porous polymers with stable pore structure. The method for synthesizing a series of polymers in the application can continue to maintain excellent pore performance and stability of products while expanding the yield, and can achieve 100g-level preparation in a one-pot method in a laboratory. In addition, the porous polymer microspheres synthesized in the application have the characteristics of low monomer cost, simple synthesis method, batch production, good adsorption catalytic performance and the like, and have practical industrialization potential.

Description

Technical Field

[0001] This invention specifically relates to a series of melamine-based porous polymer microspheres that can be mass-produced, belonging to the field of porous organic polymer materials. Background Technology

[0002] With rapid economic development, the discharge of industrial wastewater is increasing daily. The main pollutants in industrial wastewater are organic solvents and dyes, which are typically characterized by high organic pollutant content, complex composition, and good chemical stability. Even small amounts discharged into water bodies can cause long-term damage due to their difficulty in natural degradation. Currently, treatment methods for these two pollutants include chemical precipitation, biological treatment processes, electrochemical methods, and adsorption. Among these, adsorption, especially using solid adsorbents, is the most common method. This method has a relatively simple overall process; after adsorption, the organic pollutants in the liquid phase adhere to the inside of the adsorbent, and the collection and removal of organic pollutants in the water can be achieved simply by removing the adsorbent.

[0003] Over the past few decades, the use of adsorbent materials to collect and recycle organic pollutants in water has been a promising method, attracting considerable attention due to their high purification efficiency and ease of operation. For adsorption methods, the performance of the adsorbent plays a decisive role in the adsorption effect. Traditional adsorbents include activated carbon, montmorillonite, and kaolin, but these inorganic traditional adsorbents suffer from simple pore structures, small specific surface areas, few surface reactive groups, and low potential for subsequent functionalization. Therefore, the development of novel solid adsorbent materials is needed. Among these, microporous organic polymers (MOPs) formed by the stacking of organic molecules have attracted increasing interest due to their defined porosity, high surface area, light weight, and ease of use.

[0004] A large number of studies have focused on developing synthesis strategies for MOPs with good controllable porosity, morphology and composition. Commonly including hypercrosslinked polymers (HCPs), intrinsic microporous polymers (PIMs), conjugated microporous polymers (CMPs) and covalent organic frameworks (COFs), MOPs materials have been developed and applied in many fields, such as gas storage and separation, catalysis, adsorbents, energy storage, sensors, etc., and have shown good performance. Due to their controllable porous properties, high specific surface area and outstanding physical stability, MOPs can be widely used as efficient adsorbents for water pollutants, such as metal ions, dyes, organic solvents and oils, and some of the adsorbents (such as some COFs) have special properties of photocatalytic degradation of pollutants while adsorbing pollutants. However, most of these MOPs are prepared using high-cost starting materials or catalysts, which makes the large-scale production of materials challenging and limits practical applications. Therefore, especially for microporous solid adsorbents, high synthesis cost, complex synthesis steps and difficulty in mass production are important reasons why such microporous materials are difficult to leave the laboratory and be put into industrial use. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a method for batch synthesis of a series of melamine-based porous polymer microspheres, which solves the problems of high synthesis cost and difficulty in batch production of microporous polymers in the prior art.

[0006] The technical scheme adopted by the present application to solve the above-mentioned problems is:

[0007] The batch preparation method of a series of melamine-based porous polymer microspheres mainly comprises the following steps:

[0008] Step one, mix melamine monomers (i.e. reaction monomer A) with a solvent (such as N,N-dimethylacetamide (DMAC)), repeatedly shake and ultrasonic until the solid powder completely disappears, then add appropriate monomers with different types of functional groups (i.e. reaction monomer B), and perform the same shaking and ultrasonic operation to make the two reaction monomers completely dispersed in the solvent to obtain a monomer mixed solution; wherein the monomer with different types of functional groups is a monomer that can react with amino groups to form a crosslinked structure, and the functional groups are one or more of isocyanate groups, acid anhydride groups and aldehyde groups.

[0009] Step two, add an appropriate amount of emulsifier to the uniformly dispersed monomer mixed solution obtained in step one, and stir at 30-50°C for 2-6h to fully emulsify to form colloidal microspheres;

[0010] Step three, based on step two, the reaction temperature is raised to 80-130℃ for 20-80h to further cross-link and polymerize the colloidal microspheres obtained in step two to form stable cross-linked porous structure;

[0011] Step four, the solution after step three is washed repeatedly with DMAC, ethanol, deionized water and the like, and then centrifuged, and then freeze-dried to obtain the corresponding melamine-based porous polymer microsphere powder.

[0012] According to the above scheme, the monomers of different types of functional groups can be one or more monomers of the same type of functional groups, or one or more monomers of different types of functional groups, preferably one or more monomers of the same type of functional groups. Further preferably, the monomers of different types of functional groups are one of p-phenylene diisocyanate, pyromellitic anhydride, p-phenylenedimethylformaldehyde, etc.

[0013] According to the above scheme, the emulsifier includes one or more of alkylphenol polyoxyethylene ether (OP-10), polyethylene glycol octylphenyl ether (Triton X-100), polysorbate (Tween-80), etc.

[0014] According to the above scheme, when p-phenylene diisocyanate is used as the monomer of different types of functional groups in step one, the reaction temperature in step three is 80-100℃, the reaction time is 20-30h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous polyurea microsphere powder; when pyromellitic anhydride is used as the monomer of different types of functional groups in step one, the reaction temperature in step three is 110-130℃, the reaction time is 20-30h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous polyimide microsphere powder; when p-phenylenedimethylformaldehyde is used as the monomer of different types of functional groups in step one, the reaction temperature in step three is 110-130℃, the reaction time is 65-80h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous aminoaldehyde polymer microsphere powder. Different types of products can only be formed into porous polymer microspheres with cross-linked structure by using the corresponding reaction temperature and reaction time. The present application exemplifies three monomers containing functional groups that can react with amino groups (i.e. p-phenylene diisocyanate, pyromellitic anhydride, p-phenylenedimethylformaldehyde), as long as other monomers can react with amino groups to form cross-linked structure, and by selecting appropriate reaction temperature and time, other types of polymer microspheres can also be synthesized in batches by the same process.

[0015] According to the above scheme, in step one, the molar ratio of melamine monomer to monomers with different types of functional groups is 2:3; wherein the functionality of the melamine monomer is 3, and the functionality of the monomers with different types of functional groups is 2. The solid content of the two reaction monomers in the solvent is 2% to 20% (the solid content is calculated as the total mass of the two reaction monomers accounting for the percentage of the volume of the solvent).

[0016] According to the above scheme, in step two, the content of the emulsifier is 2 to 4% of the total mass of the two reaction monomers.

[0017] The present application can prepare a series of melamine-based porous polymer microspheres that can be mass-produced by dispersing and polymerizing melamine monomers with different types of functional groups and subsequent crosslinking reaction. The present application mainly synthesizes three types of porous polymer microspheres, polyurea, polyimide and amino-aldehyde polymer, based on melamine. The emulsifier is added to form spherical colloidal particles (i.e. using a method similar to dispersion polymerization, melamine-based latex particles) at a relatively low temperature (30 to 50°C, and a temperature that is too high will destroy the stabilizing effect of the emulsifier), and then further crosslinking polymerization is carried out to make the monomers fully react to form porous polymer microspheres with crosslinked structure and stable pore structure. Among them, the introduction of emulsifier to form spherical colloidal particles can make the reaction monomers uniformly and stably distributed therein, which can greatly improve the solid content while ensuring the stability of the overall synthesis reaction, at the same time, the polymer exists in the form of spherical particles, and the pore structure generated by the stacking of the particles will be more than that of irregularly shaped polymers, which can improve the overall pore performance of the polymer; moreover, the solid content of various polymer reaction monomers can be from 2% to 20%, and the porous polymer microspheres can be prepared, the particle size can be maintained at 100 to 500 nm, and the specific surface area can be within 5%, and the yield can reach 100g under laboratory conditions. The polymer synthesized by this method can continue to maintain excellent pore performance and stability while expanding the yield, and can achieve 100g preparation in a laboratory "one-pot" method, and can realize mass production with high solid content without causing too much impact on the pore performance.

[0018] In the above preparation method, when the solid content of the two reaction monomers in the solvent is 2%, the particle size of the series of melamine-based porous polymer microspheres prepared is about 100-200 nm, and even when the solid content is increased to a maximum of 20%, the particle size of the series of melamine-based porous polymer microspheres prepared can be maintained at 400-500 nm; at the same time, when the solid content of the two reaction monomers in the solvent is in the range of 2%-20%, the specific surface area of the porous polymer microsphere product obtained at each solid content fluctuates within 5%, and the original pore structure and pore performance can be maintained. Under the combined action of polymerization and crosslinking, a large number of microporous and mesoporous structures can be formed in the melamine-based porous polymer, which can effectively adsorb organic solvents or dye molecules in industrial wastewater. The excellent pore structure and stability make the porous polymers have good adsorption performance, and the characteristic groups on the surface of each different polymer microsphere also have the potential to selectively adsorb and separate some special solvents. The ammonia aldehyde polymer with a covalent framework structure can also realize catalytic degradation of organic pollutants under visible light conditions, realizing the cycle effect of adsorption-degradation-readsorption of pollutants.

[0019] Compared with the prior art, the beneficial effects of the present application are:

[0020] First, the traditional synthesis method of microporous organic polymers has high selectivity requirements for the synthesis of monomers. When synthesizing different types of polymers, the synthesis method and conditions differ greatly, so most synthesis methods are only suitable for a specific type of microporous polymer material. The series of porous polymer microspheres prepared by the present application are based on melamine monomers, and a series of monomers with different functional groups are selected for reaction by utilizing the reaction possibility of amino groups and multi-functional groups. A variety of different types of microporous polymer microspheres are successfully synthesized by using a basic preparation method, which shows that the preparation method is universal for the synthesis of melamine-based porous polymers and has the potential to synthesize more different types of melamine-based porous polymers.

[0021] Second, the reaction monomers, catalysts or crosslinking agents of traditional microporous organic polymers are relatively expensive, and are accompanied by harsh reaction conditions, multiple reaction steps, and complex post-treatment and purification processes, which inevitably causes sample loss and limits the yield. The present application selects several low-cost reaction monomers, does not use any catalysts and crosslinking agents, and only uses a simple one-pot method to synthesize microporous organic polymers, which avoids the complex post-treatment process and ensures the yield of the porous polymer microspheres.

[0022] Third, the synthesis reaction of traditional microporous organic polymers controls the solid content at a low level to prevent the influence of polymer agglomeration, so as not to affect the specific surface area and pore structure of the polymer. The solid content gradient of several microporous polymers prepared by the method of the present application can be improved to 20%, and the most important pore performance of the sample will not be affected.

[0023] Fourth, traditional microporous polymers are basically designed for pore size structure and polymer particle size, and only reflect the modification of adsorption capacity. The method for preparing microporous polymers in the present application can design microporous polymers with other functions in addition to adsorption capacity for different application scenarios by selecting reaction monomers with different functional groups, and has the potential for functional modification. For example, the ammonia aldehyde polymer introduced in the present application can have good photocatalytic effect due to the structure of the covalent organic framework, and can realize adsorption-degradation-adsorption, realize in-situ degradation after adsorption of pollutants, and avoid the cumbersome post-processing process compared with traditional microporous adsorption materials.

[0024] In summary, the polymer synthesized by the present application has the characteristics of low monomer cost, simple synthesis method, batch production, good adsorption and catalytic performance, and has the potential for practical industrialization. At the same time, the three kinds of porous polymer microspheres synthesized by improving the solid content to realize batch synthesis can all maintain excellent pore structure and physical stability, which proves that the method is completely suitable for large-scale synthesis. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The infrared (FT-IR) curves of different types of melamine-based porous polymers in Example 1, wherein PU is the infrared (FT-IR) curve of polyurea; PI is the infrared (FT-IR) curve of polyimide; and PM is the infrared (FT-IR) curve of ammonia aldehyde polymer.

[0026] Figure 2 The isothermal nitrogen adsorption-desorption curves and BJH pore size distribution curves of different types of melamine-based porous polymers in Example 1, PU, PI and PM correspond to polyurea, polyimide and ammonia aldehyde polymer, respectively.

[0027] Figure 3 The SEM images corresponding to the melamine-based porous polymer microspheres of different types in Example 1, Figures A-C correspond to polyurea, polyimide and ammonia aldehyde polymer, respectively.

[0028] Figure 4 The isothermal nitrogen adsorption-desorption curves and BJH pore size distribution curves of polyurea porous polymer microspheres with different solid contents, PU-1, PU-2, PU-3 and PU-4 correspond to polyurea nanoparticles with solid contents of 2%, 5%, 10% and 20%, respectively.

[0029] Figure 5 In the figure, A is the UV absorption spectrum of the ammonia-aldehyde polymer microporous polymer with a covalent organic framework structure degrading methylene blue under natural light conditions; B is a comparison of the photocatalytic degradation curve of methylene blue by the addition of the ammonia-aldehyde polymer microporous polymer and the degradation curve of methylene blue by the control group. Detailed Implementation

[0030] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the present invention is not limited to the following embodiments.

[0031] In the following examples, the molar ratio of melamine to terephthalic diisocyanate / pyromellitic anhydride / terephthalaldehyde is 2:3.

[0032] Example 1

[0033] A series of methods for preparing melamine-based porous polymer microspheres, comprising the following steps:

[0034] 1.1 Preparation process of porous polyurea microspheres:

[0035] Add 0.757 g (6 mmol) of melamine to a beaker, add N,N-dimethylformamide (DMF), and sonicate in an ultrasonic machine until the melamine is completely dissolved. Then weigh 1.441 g (9 mmol) of terephthalic diisocyanate and add it to the beaker, sonicating again until the raw material is completely dissolved (no solid or lumpy residue remains after pouring), with a solid content of 2%. Pour the ultrasonically dispersed mixture into a 150 ml round-bottom flask and heat it to 40°C in a constant-temperature oil bath. When the temperature stabilizes at 40°C, add 3% by weight of the emulsifier—alkylphenol polyoxyethylene ether-10 (OP-10). Then maintain emulsification at 40°C for 1 hour, adjust the temperature to 90°C, and react for 24 hours. Collect the reaction product in centrifuge tubes, shake evenly with a shaker, and then centrifuge at 10000 r / min for 5 minutes. Centrifuge three times each with DMF, acetone, and distilled water to obtain the desired product. Finally, add an appropriate amount of distilled water to the product and freeze-dry it in a refrigerator to obtain the final product, melamine-based porous polyurea microsphere powder, labeled as polyurea (PU).

[0036] 1.2 Preparation process of porous polyimide microspheres:

[0037] Add 0.757 g (6 mmol) of melamine to a beaker, add N,N-dimethylformamide (DMF), and sonicate in an ultrasonic machine until the melamine is completely dissolved. Then weigh 1.963 g (9 mmol) of pyromellitic anhydride and dissolve it in N,N-dimethylformamide (DMF). Sonicate again until the raw material is completely dissolved (no solid or lumpy residue remains after pouring). Place the solution in a constant pressure dropping funnel. The total solid content is 2%. The ultrasonically dispersed melamine solution was poured into a 150 ml round-bottom flask and heated to 40°C in a constant-temperature oil bath. Once the temperature stabilized at 40°C, 3% (by weight) of the emulsifier—alkylphenol polyoxyethylene ether-10 (OP-10)—was added. While maintaining the 40°C condition, the uniformly dispersed pyromellitic anhydride was added dropwise using a dropping funnel. The pyromellitic anhydride solution was completely added to the flask over 0.5 hours, and emulsification continued at 40°C for 1 hour. The temperature was then adjusted to 120°C, and the reaction was allowed to proceed for 24 hours. The reaction product was collected in centrifuge tubes, homogenized using a shaker, and then centrifuged at 10000 rpm for 5 minutes. The product was obtained by centrifuging three times each with DMF, ethanol, and distilled water. Finally, an appropriate amount of distilled water was added to the product, and the mixture was freeze-dried to obtain the final product: melamine-based porous polyimide microsphere powder, labeled as polyimide (PI).

[0038] 1.3 Preparation process of porous aminoaldehyde polymer microspheres:

[0039] Add 0.757 g (6 mmol) of melamine to a beaker, add N,N-dimethylformamide (DMF), and sonicate in an ultrasonic machine until the melamine is completely dissolved. Then weigh 1.207 g (9 mmol) of terephthalaldehyde and add it to the beaker, sonicating again until the raw material is completely dissolved (no solid or lumpy residue remains after pouring), with a solid content of 2%. Pour the ultrasonically dispersed mixture into a 100 ml round-bottom flask and heat it to 40°C in a constant-temperature oil bath. When the temperature stabilizes at 40°C, add 4% by weight of the emulsifier—alkylphenol polyoxyethylene ether-10 (OP-10). Then maintain emulsification at 40°C for 1 hour, adjust the temperature to 120°C, and react for 72 hours. Collect the reaction product in centrifuge tubes, shake evenly with a shaker, and then centrifuge at 7500 r / min for 5 minutes. Centrifuge three times each with DMF, ethanol, and distilled water to obtain the desired product. Finally, an appropriate amount of distilled water was added to the product and placed in a refrigerator for freeze-drying to obtain the final product, melamine-based porous ammonia-aldehyde polymer microsphere powder, labeled as ammonia-aldehyde polymer (PM).

[0040] like Figure 1 As shown in the infrared spectrum, the three types of melamine-based porous polymers prepared in this embodiment all have a wavelength range of 1460-1550 cm⁻¹. -1triazine ring characteristic peak of melamine, proving the existence of triazine ring framework in each polymer, urea bond characteristic peak 1637 cm -1 of polyurea and imide bond characteristic peak 1727 cm -1 of polyimide, proving the successful synthesis of the corresponding porous polymer, the disappearance of imine characteristic peak 1600 cm -1 of aldehyde group characteristic peak 1690 cm -1 of the monomer can prove the successful synthesis of the aldehyde-ammonia porous polymer.

[0041] As shown in Figure 2 , through the isothermal nitrogen adsorption-desorption curves of Figure A, it can be seen that the three curves of the three melamine-based porous polymers all have a rapid increase in adsorption volume at low pressure (P / P0<0.1), and there is a hysteresis loop when the relative pressure (P / P0) is greater than 0.4, indicating that the three melamine-based porous polymers all have a large number of micropores and mesopores, and the specific surface areas of PU, PI and PM are 85 m 2 ·g -1 , 113 m 2 ·g -1 , and 28 m 2 ·g -1 , respectively. The BJH pore size distribution curves of Figure B also show that the pore size distribution of the three melamine-based porous polymers is mainly concentrated around 2 nm, proving that the pore structure is mainly microporous and smaller mesoporous.

[0042] As shown in Figure 3 , through SEM it can be seen that the three melamine-based porous polymer microspheres prepared all have typical spherical morphology structure, and the size of the individual polymer microspheres is basically between 100-300 nm.

[0043] Example 2

[0044] The difference between Example 2 and Example 1 is that Example 2 takes the synthesis of melamine-based porous polyurea microspheres as an example, and changes the solid content of the reaction monomers in the synthesis process, i.e. the total mass of melamine (MA) and p-phenylene diisocyanate (PDI) accounts for 2%, 5%, 10% and 20% of the volume of the reaction solvent, so as to explore the influence of increasing the solid content of the reaction monomers on the particle size and overall pore performance of the synthesized porous polyurea microspheres, and verify whether this method can realize batch production.

[0045] The overall operation steps for synthesizing porous polyurea microspheres introduced in Example 1 are the same, only the mass of the two reaction monomers is changed to increase the overall solid content of the reaction.

[0046] Table 1 shows the BET specific surface area, average pore size, pore volume, and nanoparticle size of porous polyurea nanospheres with different solid contents.

[0047] Table 1

[0048]

[0049] pass Figure 4 Comparing the isothermal nitrogen adsorption-desorption curves, BJH pore size distribution curves, and specific surface area data in Table 1, it was found that even with a gradual increase in solid content, the specific surface area of ​​the porous polyurea nanospheres did not fluctuate significantly, and the pore structure remained predominantly micropores and mesopores. This demonstrates that increasing the solid content does not affect the pore properties of the prepared porous polymer. Note: The average pore size in Table 1 is larger than that of the nanospheres in Example 1 with the same solid content. This is mainly due to particle packing, which causes the average pore size displayed by the instrument to be larger than expected. Figure 2 The aperture distribution curve.

[0050] Furthermore, in the laboratory, using a 250ml container, 7.567g of melamine (MA, 60mmol) and 14.411g of terephthalic diisocyanate (PDI, 90mmol), 110mL of DMF as reactants and solvents, with an emulsifier at 3% of the monomer mass, and a solid content of 20% for both melamine and terephthalic diisocyanate, the "one-pot method" described in this invention can produce porous polyurea nanospheres in a single batch exceeding 10g. Therefore, under the condition that a 2.5L reaction container is available in the laboratory, scaling up the reactants by 10 times can achieve the production of porous polyurea nanospheres at the 100g level.

[0051] Example 3

[0052] In Example 3, based on the porous amino aldehyde polymer microspheres prepared in Example 1, it was analyzed that they have a covalent organic framework structure and are considered to have a certain photocatalytic degradation ability. Therefore, the photocatalytic degradation of dyes was tested on them.

[0053] First, a 10 ppm methylene blue (MB) solution was prepared. 25 mg of ammonia-aldehyde polymer microspheres (PM) solid powder were weighed, and 100 mL of the prepared MB solution was measured. The PM powder was then transferred into the solution, wrapped in aluminum foil to protect it from light, and ultrasonically dispersed to obtain a homogeneous dispersion. The solution was then unwrapped from the foil and transferred to a photocatalytic device. A simulated visible light lamp was turned on for illumination. 2 mL of the solution was collected every 10 minutes, centrifuged at high speed, and the supernatant was measured for UV absorbance. Based on the strong absorption peak of methylene blue at 664 nm, the UV absorption spectrum of the MB solution as the illumination time increased was obtained by measuring the change in absorbance, and the photocatalytic degradation efficiency could then be calculated.

[0054] As Figure 5 As shown in Figure 13, compared with the blank control group without PM, the absorption peak of the solution containing PM group under ultraviolet light decreased significantly with time, indicating that the prepared porous ammonia aldehyde polymer can better photocatalytic degradation of methylene blue.

[0055] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the inventive concept, several improvements and changes can be made, which are within the scope of the present application.

Claims

1. A method for batch production of melamine-based porous polymeric microspheres, characterized in that The main steps are as follows: Step one, mix the monomer melamine with the solvent N,N-dimethylacetamide until the melamine is uniformly dissolved, then add the appropriate monomer of different types of functional groups, and fully disperse the two reaction monomers in the solvent to obtain a monomer mixed solution; wherein the molar ratio of the melamine monomer to the monomer of different types of functional groups is 2:3, and the solid content of the two reaction monomers in the solvent is 2-20%; the monomer of different types of functional groups is one of p-phenylene diisocyanate, pyromellitic anhydride, and p-phenylenedimethylformaldehyde; Step two, add an emulsifier to the uniformly dispersed monomer mixed solution obtained in step one, and stir at 30-50 DEG C for 2-6 h to fully emulsify to form colloidal microspheres; wherein the emulsifier includes one or more of alkylphenol polyoxyethylene ether, polyethylene glycol octylphenyl ether, and polysorbate; Step three, on the basis of step two, the reaction temperature is increased to 80-130 DEG C for 20-80 h to further cross-link and polymerize the colloidal microspheres obtained in step two to form a stable cross-linked pore structure; Step four, after the solution after the reaction in step three is washed and centrifuged, it is frozen and freeze-dried to obtain the corresponding different types of melamine-based porous polymer microsphere powder, wherein the particle size of the microspheres is in the range of 100-500 nm, the specific surface area fluctuation interval is within 5%, the pore size of the microspheres is 1.5-2.5 nm, and the pore structure is mainly microporous and mesoporous.

2. The process for batch preparation of melamine-based porous polymeric microspheres according to claim 1, characterized in that When the monomer of different types of functional groups in step one is p-phenylene diisocyanate, the reaction temperature in step three is 80-100 DEG C, and the reaction time is 20-30 h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous polyurea microsphere powder; when the monomer of different types of functional groups in step one is pyromellitic anhydride, the reaction temperature in step three is 110-130 DEG C, and the reaction time is 20-30 h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous polyimide microsphere powder; when the monomer of different types of functional groups in step one is p-phenylenedimethylformaldehyde, the reaction temperature in step three is 110-130 DEG C, and the reaction time is 65-80 h, and the corresponding melamine-based porous polymer microsphere powder is melamine-based porous aminoaldehyde polymer microsphere powder.

3. The method for batch preparation of melamine-based porous polymeric microspheres according to claim 1, characterized in that In step two, the content of the emulsifier is 2-4% of the total mass of the two reaction monomers.

4. The process for batch preparation of melamine-based porous polymeric microspheres according to claim 1, characterized in that In step one, when the solid content of the two reaction monomers in the solvent is 2%, the particle size of the series of melamine-based porous polymer microspheres prepared in step four is 100-200 nm; when the solid content of the two reaction monomers in the solvent is 20%, the particle size of the series of melamine-based porous polymer microspheres prepared is 400-500 nm; when the solid content of the two reaction monomers in the solvent is increased from 2% to 20% in step one, the particle size of the microspheres increases from 100-200 nm to 400-500 nm.

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