A method for producing a macroporous acrylic high molecular polymer

Abstract

The application belongs to the technical field of resin production, and particularly relates to a macroporous acrylic high-molecular polymer production method. The steps are as follows: adding gelatin, Tween 20 and hydroxyethyl cellulose into soft water to prepare water phase; mixing methyl acrylate, acrylonitrile, trimethylolpropane trimethacrylate, benzoyl peroxide and ethylene glycol dimethacrylate with toluene to prepare organic phase, adding the organic phase into the water phase, shearing and emulsifying to obtain emulsion, and polymerizing to obtain polymer spheres; finally, adding a mixed solution of crosslinking agent, benzoyl peroxide and propylene carbonate into the mixed solution again for crosslinking reaction to obtain high-molecular polymer. The application adopts specific reagents and secondary crosslinking, can realize preparation of macroporous high-molecular polymer, and can accurately control the pore structure to ensure the product performance. The prepared high-molecular polymer has high porosity and large pore size, and has excellent effect. Moreover, the operation is simple, and the industrial production can be easily realized, so the application has wide application prospect.

Description

Technical Field

[0001] This invention belongs to the field of resin production technology, specifically relating to a method for producing macroporous acrylic polymers. Background Technology

[0002] Ion exchange resins are a class of polymeric functional materials with a three-dimensional cross-linked network structure. Their molecular chains contain fixed active functional groups with ion exchange capabilities. These substances achieve reversible ion exchange reactions through functional groups in the backbone. The material system comprises three core components: (1) a rigid matrix network: an insoluble spatial backbone composed of cross-linked polymers, providing mechanical stability; (2) functional coordination units: specific reactive groups covalently bonded to the backbone, determining resin properties; and (3) dynamic exchange ions: counterions with charge balance to the functional groups, enabling material exchange. Furthermore, ion exchange resin products are diverse; classified by the characteristics of active groups, they can be cationic, anionic, and special functional types. Cationic types include strong acid types (sulfonic acid groups) and weak acid types (carboxylic acid groups); anionic types include strong base types (quaternary ammonium groups) and weak base types (primary amine groups); and special functional types include chelating types, zwitterionic types, and redox types. The applications of ion exchange resins mainly include water treatment resins, adsorption and separation resins, and catalytic reaction resins.

[0003] Currently, the field of polymer synthesis technology is showing a diversified development trend, and the main research includes the following core methods: (1) suspension polymerization, which achieves polymerization through the stable dispersion of monomer droplets in a continuous phase; (2) dispersion polymerization, which forms a homogeneous reaction system at the colloidal scale; (3) emulsion polymerization, which uses surfactants to construct a micro-reaction environment; and (4) seed swelling polymerization, which uses prepolymers to control particle size gradients. For example, some literature uses the emulsification method to prepare macroporous polymers. The scheme is to first prepare a water-in-oil-in-water complex emulsion as a template for the ultra-macroporous polymer, then use a solvent removal method to solidify the oil phase, and finally crosslink the microsphere skeleton molecules. Although it can obtain macroporous polymers, the method is relatively complex and not conducive to practical production applications. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for producing macroporous acrylic polymers. The polymers prepared by this method are not only simple and easy to operate, but also possess ultra-large pores and excellent properties.

[0005] To achieve the above objectives, the present invention adopts the following technical solution;

[0006] A method for producing macroporous acrylic polymers, comprising the following steps:

[0007] (1) Preparation of aqueous phase: Add gelatin to softened water, heat to dissolve, then add Tween 20 and hydroxyethyl cellulose, heat and stir evenly to obtain aqueous phase for later use; wherein the amount of softened water, gelatin, Tween 20 and hydroxyethyl cellulose is 1000~1200ml: 5~10g: 2-4g: 3~5g.

[0008] (2) Preparation of organic phase: Methyl acrylate, acrylonitrile and trimethylolpropane trimethacrylate are mixed in proportion and added to the mixing tank; then benzoyl peroxide is added to ethylene glycol dimethacrylate, stirred evenly, and then added to the mixing tank; finally, toluene is added and stirred evenly to obtain the organic phase for later use; wherein, the mass ratio of methyl acrylate, acrylonitrile, trimethylolpropane trimethacrylate, benzoyl peroxide, ethylene glycol dimethacrylate and toluene is 25-40:120-150:10-15:1-3:1-3:60-70;

[0009] (3) Add the organic phase prepared in step (2) to the aqueous phase prepared in step (1) and perform shear emulsification to form an O / W type emulsion; then transfer the O / W type emulsion to a reaction vessel, heat it to 50-55℃, maintain the reaction for 1-2 hours, then heat it to 82-86℃ and maintain the reaction for 2-3 hours. After the reaction is completed, transfer it to an oil blowing vessel, filter out the reaction liquid, and obtain polymer spheres.

[0010] (4) Add the crosslinking agent and benzoyl peroxide to propylene carbonate, then transfer it to a reaction vessel, and add the polymer spheres obtained in step (3) to the reaction vessel. Heat the mixture to 80-82°C and maintain the reaction for 2-4 hours to achieve a second crosslinking reaction of the polymer molecules. The crosslinking agent is composed of ethylene glycol dimethacrylate and divinylbenzene. After the reaction, wash the mixture to obtain a polymer.

[0011] Preferably, the heating and melting temperature in step (1) is 60-70°C.

[0012] Preferably, the heating and stirring temperature in step (1) is 50-55°C; and the stirring time is 20-30 min.

[0013] Preferably, the mass ratio of the organic phase to the aqueous phase in step (3) is 1:6 to 10.

[0014] Preferably, the shear emulsification conditions in step (3) are: 10,000 to 20,000 rpm for 2 to 4 minutes.

[0015] Preferably, the mass ratio of polymerized spheres to propylene carbonate in step (4) is 1:5-10.

[0016] Preferably, in step (4), the mass ratio of crosslinking agent, benzoyl peroxide and propylene carbonate is 0.01-0.05:0.01-0.05:1.

[0017] Preferably, in step (4), the mass ratio of ethylene glycol dimethacrylate to divinylbenzene is 2:0.5-1.

[0018] The beneficial effects of this invention are:

[0019] (1) In the preparation process of the aqueous phase, gelatin is added. Gelatin is a natural amphiphilic macromolecule with excellent surface activity. Using it as an emulsifier can improve the stability of the final emulsion. At the same time, cellulose is used as a dispersant in the aqueous phase, and Tween 20 is used as an surfactant to make the emulsion more stable, thereby making the sphericity of the prepared polymer more rounded. In addition, the present invention uses trimethylolpropane trimethacrylate, which can effectively improve the product's anti-fouling, high strength, large pore size, heat resistance, corrosion resistance, and oxidation resistance. At the same time, the combination of ethylene glycol dimethacrylate in the copolymerization can increase the product's hardness, heat resistance, weather resistance, and solvent resistance, which is beneficial to subsequent processing and application.

[0020] (2) Traditional methods often require a high proportion of aqueous phase, reaching tens or even hundreds of times, when preparing emulsions; however, this invention does not require the addition of a high proportion of aqueous phase. By controlling the shear emulsification conditions in conjunction with process control, an emulsion structure with high internal phase characteristics can be prepared. Finally, this invention crosslinks the polymer spheres, effectively realizing the preparation of macroporous polymers and ensuring that the polymers possess excellent properties.

[0021] (3) The polymer prepared by this invention has high porosity, large pore size and excellent comprehensive performance; moreover, it is easy to operate and can be easily industrialized to produce polymers, and has broad application prospects. Detailed Implementation

[0022] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0023] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0024] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0025] Example 1:

[0026] The preparation steps of the porous acrylic polymer are as follows:

[0027] (1) Preparation of aqueous phase: Add 500g gelatin to 100L of softened water and heat to 65℃ to dissolve; then add 400g Tween 20 and 300g hydroxyethyl cellulose, and stir for 30min at a heating temperature of 50℃ to obtain an aqueous phase.

[0028] (2) Preparation of organic phase: Mix 4 kg of methyl acrylate, 12 kg of acrylonitrile and 1.5 kg of trimethylolpropane trimethacrylate; then add 300 g of benzoyl peroxide to 300 g of ethylene glycol dimethacrylate, stir evenly, and then add it together with the mixture of methyl acrylate and trimethylolpropane trimethacrylate into the mixing tank. Finally, add 6.5 kg of toluene, stir evenly, and prepare the organic phase for later use.

[0029] (3) Add the organic phase prepared in step (2) to the aqueous phase prepared in step (1) at a ratio of 1:8 and perform shear emulsification under the following conditions: 20000 rpm for 2 min. After emulsification, an O / W type emulsion is formed. Then, the O / W type emulsion is transferred to a reaction vessel, heated to 55°C, and maintained for 2 h. Then, the temperature is raised to 82°C and maintained for 2 h. After the reaction is completed, the reaction liquid is filtered off to obtain polymerized spheres.

[0030] (4) Add 400g of ethylene glycol dimethacrylate, 200g of divinylbenzene, and 300g of benzoyl peroxide to 10kg of propylene carbonate, then transfer the mixture to a reactor. Add 1.5kg of the polymer spheres obtained in step (3) to the reactor, heat to 80℃, and maintain the reaction for 4h to achieve a second crosslinking reaction of the polymer molecules. After the reaction, wash the mixture to obtain the polymer. The test results are shown in Table 1.

[0031] Example 2:

[0032] The preparation steps of the porous acrylic polymer are as follows:

[0033] (1) Preparation of aqueous phase: Add 500g gelatin to 100L of softened water and heat to 65℃ to dissolve; then add 200g Tween 20 and 300g hydroxyethyl cellulose, and stir for 30min at a heating temperature of 50℃ to obtain an aqueous phase.

[0034] (2) Preparation of organic phase: Mix 3 kg of methyl acrylate, 14 kg of acrylonitrile and 1.0 kg of trimethylolpropane trimethacrylate; then add 300 g of benzoyl peroxide to 200 g of ethylene glycol dimethacrylate, stir evenly, and then add it together with the mixture of methyl acrylate and trimethylolpropane trimethacrylate into the mixing tank. Finally, add 6.5 kg of toluene, stir evenly, and prepare the organic phase for later use.

[0035] (3) Add the organic phase prepared in step (2) to the aqueous phase prepared in step (1) at a ratio of 1:10 and perform shear emulsification under the following conditions: 20000 rpm for 2 min. After emulsification, an O / W type emulsion is formed. Then, the O / W type emulsion is transferred to a reaction vessel, heated to 55°C, and maintained for 2 h. Then, the temperature is raised to 82°C and maintained for 2 h. After the reaction is completed, the reaction liquid is filtered off to obtain polymer spheres.

[0036] (4) Add 400g of ethylene glycol dimethacrylate, 100g of divinylbenzene, and 400g of benzoyl peroxide to 10kg of propylene carbonate, then transfer the mixture to a reactor. Add 1.5kg of the polymer spheres obtained in step (3) to the reactor, heat to 82℃, and maintain the reaction for 4h to achieve a second crosslinking reaction of the polymer molecules. After the reaction, wash the mixture to obtain the polymer. The test results are shown in Table 1.

[0037] Example 3:

[0038] The preparation steps of the porous acrylic polymer are as follows:

[0039] (1) Preparation of aqueous phase: Add 600g gelatin to 100L of softened water and heat to 65℃ to dissolve; then add 300g Tween 20 and 400g hydroxyethyl cellulose, and stir for 30min at a heating temperature of 50℃ to obtain an aqueous phase.

[0040] (2) Preparation of organic phase: Mix 2.5 kg of methyl acrylate, 15 kg of acrylonitrile and 1.5 kg of trimethylolpropane trimethacrylate; then add 100 g of benzoyl peroxide to 300 g of ethylene glycol dimethacrylate, stir evenly, and then add it together with the mixture of methyl acrylate and trimethylolpropane trimethacrylate into the mixing tank. Finally, add 6.5 kg of toluene, stir evenly, and prepare the organic phase for later use.

[0041] (3) Add the organic phase prepared in step (2) to the aqueous phase prepared in step (1) at a ratio of 1:6 and perform shear emulsification under the following conditions: 20000 rpm for 2 min. After emulsification, an O / W type emulsion is formed. Then, the O / W type emulsion is transferred to a reaction vessel, heated to 55°C, and maintained for 2 h. Then, the temperature is raised to 82°C and maintained for 2 h. After the reaction is completed, the reaction liquid is filtered off to obtain polymerized spheres.

[0042] (4) Add 400g of ethylene glycol dimethacrylate, 200g of divinylbenzene, and 300g of benzoyl peroxide to 10kg of propylene carbonate, then transfer the mixture to a reactor. Add 1.5kg of the polymer spheres obtained in step (3) to the reactor, heat to 80℃, and maintain the reaction for 4h to achieve a second crosslinking reaction of the polymer molecules. After the reaction, wash the mixture to obtain the polymer. The test results are shown in Table 1.

[0043] Comparative Example 1:

[0044] (1) Preparation of aqueous phase: Add 500g gelatin to 100L of softened water and heat to 65℃ to dissolve; then add 400g Tween 20 and 300g hydroxyethyl cellulose, and stir for 30min at a heating temperature of 50℃ to obtain an aqueous phase.

[0045] (2) Preparation of organic phase: Mix 4 kg of methyl acrylate, 12 kg of acrylonitrile and 1.5 kg of trimethylolpropane trimethacrylate; then add 300 g of benzoyl peroxide to 300 g of ethylene glycol dimethacrylate, stir evenly, and then add it together with the mixture of methyl acrylate and trimethylolpropane trimethacrylate into the mixing tank. Finally, add 6.5 kg of toluene, stir evenly, and prepare the organic phase for later use.

[0046] (3) The organic phase prepared in step (2) was added to the aqueous phase prepared in step (1) at a ratio of 1:8, and shear emulsification was performed under the following conditions: 20,000 rpm for 2 min. After emulsification, an O / W emulsion was formed. The O / W emulsion was then transferred to a reactor, heated to 55°C, and maintained for 2 h. The temperature was then increased to 82°C and maintained for 2 h. After the reaction was completed, the reaction liquid was filtered off to obtain polymerized spheres. The test results are shown in Table 1.

[0047] Comparative Example 2:

[0048] (1) Preparation of aqueous phase: Add 500g of hydroxyethyl cellulose to 100L of softened water and stir for 30min at a heating temperature of 50℃ to obtain an aqueous phase.

[0049] (2) Preparation of organic phase: Mix 4 kg of methyl acrylate, 12 kg of acrylonitrile and 1.5 kg of trimethylolpropane trimethacrylate; then add 300 g of benzoyl peroxide to 300 g of ethylene glycol dimethacrylate, stir evenly, and then add it together with the mixture of methyl acrylate and trimethylolpropane trimethacrylate into the mixing tank. Finally, add 6.5 kg of toluene, stir evenly, and prepare the organic phase for later use.

[0050] (3) The organic phase prepared in step (2) was added to the aqueous phase prepared in step (1) at a ratio of 1:8, and shear emulsification was performed under the following conditions: 20,000 rpm for 2 min. After emulsification, an O / W emulsion was formed. The O / W emulsion was then transferred to a reactor, heated to 55°C, and maintained for 2 h. The temperature was then increased to 82°C and maintained for 2 h. After the reaction was completed, the reaction liquid was filtered off to obtain polymerized spheres. The test results are shown in Table 1.

[0051] Table 1: Detection indicators of polymers:

[0052]

[0053] References: Based on GB / T 6003.1-2012 "Technical Requirements and Inspection of Test Sieves - Part 1: Metal Wire Woven Mesh Test Sieves", particle size distribution is determined through standard sieving experiments; based on GB / T 21650.2-2008 "Determination of Pore Size Distribution and Porosity of Solid Materials by Mercury Intrusion Porosimetry and Gas Adsorption - Part 2: Analysis of Mesopores and Macropores by Gas Adsorption", pore size distribution is determined through gas adsorption or mercury intrusion porosimetry. Combined with GB / T 19587-2017 "Determination of Specific Surface Area of ​​Solid Substances by Gas Adsorption BET Method", pore size and specific surface area can be analyzed simultaneously; porosity is calculated based on volume changes by filling pores with a displacement liquid (such as water or ethanol); based on GB / T19077-2016, Dsize is obtained through sieving or laser particle size analysis. 10 and D60 Value, calculate the uniformity coefficient.

[0054] As shown in Table 1, the polymer prepared by this invention has high porosity, large pore size, and excellent comprehensive performance, realizing the production of macroporous acrylic polymers. Moreover, the process provided by this invention is simple to operate and can easily realize the industrial production of polymers, with broad application prospects.

[0055] Note: The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A method for producing macroporous acrylic polymers, characterized in that, The steps are as follows: (1) Preparation of aqueous phase: Add gelatin to softened water, heat to dissolve, then add Tween 20 and hydroxyethyl cellulose, heat and stir evenly to obtain aqueous phase for later use; wherein the amount of softened water, gelatin, Tween 20 and hydroxyethyl cellulose is 1000~1200ml: 5~10g: 2-4g: 3~5g. (2) Preparation of organic phase: Methyl acrylate, acrylonitrile and trimethylolpropane trimethacrylate are mixed in proportion and added to the mixing tank; then benzoyl peroxide is added to ethylene glycol dimethacrylate, stirred evenly, and then added to the mixing tank. Finally, toluene is added and stirred evenly to obtain the organic phase for later use; wherein, the mass ratio of methyl acrylate, acrylonitrile, trimethylolpropane trimethacrylate, benzoyl peroxide, ethylene glycol dimethacrylate and toluene is 25-40:120-150:10-15:1-3:1-3:60-70; (3) Add the organic phase prepared in step (2) to the aqueous phase prepared in step (1) and perform shear emulsification to form an O / W type emulsion; then transfer the O / W type emulsion to a reaction vessel, heat it to 50-55℃, maintain the reaction for 1-2 hours, then heat it to 82-86℃ and maintain the reaction for 2-3 hours. After the reaction is completed, transfer it to an oil blowing vessel, filter out the reaction liquid, and obtain polymer spheres. (4) Add the crosslinking agent and benzoyl peroxide to propylene carbonate, then transfer it to a reaction vessel, and add the polymer spheres obtained in step (3) to the reaction vessel. Heat the mixture to 80-82°C and maintain the reaction for 2-4 hours to achieve a second crosslinking reaction of the polymer molecules. The crosslinking agent is composed of ethylene glycol dimethacrylate and divinylbenzene. After the reaction, wash the mixture to obtain a polymer.

2. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, The heating and melting temperature in step (1) is 60-70℃.

3. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, The heating and stirring temperature in step (1) is 50-55℃; the stirring time is 20-30 min.

4. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, The mass ratio of the organic phase to the aqueous phase in step (3) is 1:6 to 10.

5. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, The shear emulsification conditions described in step (3) are: 10,000 to 20,000 rpm for 2 to 4 minutes.

6. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, In step (4), the mass ratio of polymerized spheres to propylene carbonate is 1:5-10.

7. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, In step (4), the mass ratio of crosslinking agent, benzoyl peroxide and propylene carbonate is 0.01-0.05:0.01-0.05:

1.

8. The method for producing a macroporous acrylic polymer according to claim 1, characterized in that, In step (4), the mass ratio of ethylene glycol dimethacrylate to divinylbenzene is 2:0.5-1.

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