Preparation method and application of a macrocyclic polyamine-based porous organic aerogel
By preparing macrocyclic polyamine-based porous organic aerogels, the problem of harsh application conditions for porous organic aerogels in carbon dioxide cycloaddition reactions was solved, and highly efficient catalytic cycloaddition reactions of haloepoxides and carbon dioxide were achieved, with high conversion rate and high selectivity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG UNIV OF TECH SHENGZHOU INNOVATION RES INST CO LTD
- Filing Date
- 2026-01-21
- Publication Date
- 2026-05-12
AI Technical Summary
Existing porous organic aerogels require the introduction of metal ligands or co-catalysts in carbon dioxide cycloaddition reactions, which imposes stringent application conditions and results in insufficient activity in catalysis, adsorption, and energy storage.
Using tetraazacyclododecane as the structural unit, macrocyclic polyamine porous organic aerogels were synthesized via nucleophilic substitution reactions to construct an aerogel framework rich in tertiary amine sites. The porous organic aerogels were then prepared via sol-gel polymerization and used to catalyze the cycloaddition reaction of haloepoxides with carbon dioxide.
It achieves efficient catalytic cycloaddition reaction of haloepoxides with carbon dioxide under mild conditions, with high conversion and high selectivity, and requires no addition of solvents, metals or co-catalysts.
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Figure CN121554629B_ABST
Abstract
Description
Technical Field
[0001] This application relates to a method for preparing macrocyclic polyamine-based porous organic aerogels and their applications, belonging to the field of catalyst technology. Background Technology
[0002] The cycloaddition reaction of CO2 with epoxides to form cyclic carbonates is an ideal pathway with 100% atom economy, but this reaction usually requires a catalyst to proceed efficiently. In recent years, porous organic materials have attracted widespread attention as heterogeneous catalysts. Among them, porous organic aerogels, as a novel lightweight material with a three-dimensional cross-linked network structure, exhibit unique advantages over traditional catalysts. Porous organic aerogels not only inherit the inherent characteristics of aerogel materials such as extremely high porosity, high specific surface area, and low density, but their all-organic polymer framework also endows them with excellent chemical designability and functional tunability. However, when applied to the cycloaddition reaction of carbon dioxide, the structure needs to incorporate metal ligands such as chromium, iron, aluminum, and nickel monomers / salts to form metal-organic aerogels, or introduce co-catalysts such as KI to promote the cycloaddition reaction, making the application conditions of aerogels in cycloaddition reactions quite demanding. Summary of the Invention
[0003] In view of this, this application provides a method for preparing macrocyclic polyamine porous organic aerogels, which not only achieves the mild preparation of porous organic aerogels, but also endows the aerogels with porous and highly active characteristics.
[0004] Specifically, this application is implemented through the following scheme:
[0005] A method for preparing macrocyclic polyamine-based porous organic aerogel, comprising the following steps:
[0006] Step 1: Tetraazacyclododecane reacts with chloromethylstyrene to obtain an intermediate;
[0007] Step two: The intermediate is polymerized via sol-gel and dried to obtain a macrocyclic polyamine porous organic aerogel.
[0008] The structural formula of the intermediate is: ,
[0009] The structural formula of the macrocyclic polyamine porous organic aerogel is:
[0010] .
[0011] The above process uses tetraazacyclododecane as the structural unit to synthesize 1,4,7,10-tetra(4-vinylbenzyl)-1,4,7,10-tetraazacyclododecane monomer via nucleophilic substitution reaction. Further, through sol-gel polymerization, the tetraazacyclododecane macrocyclic structure is introduced into the aerogel framework, constructing a porous organic aerogel with abundant tertiary amine sites and macrocyclic polyamine functionalization. This not only maintains the high specific surface area, tunable pore structure, and good mass transport properties of porous organic aerogels, but also exhibits excellent activity in catalysis, adsorption, and energy storage.
[0012] Furthermore, as a preferred option:
[0013] In step one,
[0014] The molar ratio of the tetraazacyclododecane to chloromethylstyrene is 1:4~10.
[0015] The chloromethylstyrene is 4-chloromethylstyrene.
[0016] The tetraazacyclododecane is dissolved in acetonitrile and dichloromethane, and then triethylamine is added. Under a nitrogen atmosphere, it reacts with chloromethylstyrene.
[0017] The reaction temperature is 50~60 ℃, and the reaction time is 20~30 h.
[0018] In step two,
[0019] The intermediate is added to a mixed solvent of chloroform and tetrahydrofuran, and then the initiator azobisisobutyronitrile is added and ultrasonically vibrated to form a sol-gel polymerization system.
[0020] The sol-gel polymerization is carried out at a temperature of 80~100 ℃ for a duration of 24~36 h.
[0021] The drying process is atmospheric pressure drying.
[0022] The aforementioned macrocyclic polyamine porous organic aerogels are used as thermal insulation materials in fields such as building exterior walls, industrial pipelines, and cold chain logistics.
[0023] The aforementioned macrocyclic polyamine-based porous organic aerogel can also serve as a heterogeneous catalyst for the cycloaddition reaction of haloepoxide substrates with carbon dioxide. This organic aerogel material not only possesses excellent CO2 adsorption capacity but also, under mild conditions without the addition of solvents, metals, or co-catalysts, catalyzes the activation of haloepoxides via a quaternization mechanism, efficiently catalyzing their cycloaddition reaction with carbon dioxide to achieve high conversion and high selectivity in the synthesis of halocyclic carbonates. Preferably, the haloepoxide substrate is epichlorohydrin or epibromopropane. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application.
[0025] Figure 1 This is a schematic diagram of the reaction process of this application.
[0026] Figure 2 The figures show a comparison between organic wet gels and organic aerogels in this application. In the figure, (a) is a macrocyclic polyamine porous organic wet gel; and (b) is a macrocyclic polyamine porous organic aerogel.
[0027] Figure 3 The images shown are scanning electron microscope (SEM) images and elemental distribution maps of PTsc. In the images, (a) is the SEM image under a 10 μm scale; (b) is the SEM image under a 5 μm scale; (c) is the SEM image under a 2 μm scale; (d) is the SEM image under a 20 μm scale; (e) is the elemental distribution map of C; and (f) is the elemental distribution map of N.
[0028] Figure 4 This is the solid-state carbon spectrum of PTSC.
[0029] Figure 5 The N2 adsorption-desorption curves of PTsc and PTsc-ECH at 77 K are shown.
[0030] Figure 6 The figure shows the carbon dioxide adsorption performance of PTsc. (a) is the gas adsorption isotherm of PTsc at 273 K; (b) is the gas adsorption isotherm of PTsc at 298 K; and (c) is the isochoric adsorption thermal curve of PTsc for carbon dioxide.
[0031] Figure 7 This is the thermogravimetric analysis spectrum of PTSC.
[0032] Figure 8 The figure shows the catalytic performance of PTsc on the cycloaddition reaction of substrate ECH. In the figure, (a) is the conversion effect of ECH with reaction time; and (b) is the conversion effect of ECH with temperature.
[0033] Figure 9 The figure shows the catalytic performance of PTsc on the cycloaddition reaction of substrate EPB. In the figure, (a) is the conversion effect of EPB with reaction time; and (b) is the conversion effect of EPB with temperature.
[0034] Figure 10The images show infrared images of PTsc aerogel at 100℃ for different durations. In the figure, (a) is the infrared image at 0 min; (b) is the infrared image at 5 min; (c) is the infrared image at 15 min; (d) is the infrared image at 30 min; and (e) is the infrared image at 60 min. Detailed Implementation
[0035] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the technical solutions in the embodiments of this application will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit the technical solutions of this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without creative effort are within the scope of protection of this application.
[0036] The reagents involved in this embodiment are as follows:
[0037] Tetraazacyclododecane, AR, Adamas; Triethylamine, AR, Adamas; 4-Chloromethylstyrene, AR, Adamas; Azobisisobutyronitrile, AR, MACKLIN; Tetrahydrofuran, AR, GENERAL-REAGENT; Chloroform, AR, Shuanglin; Dichloromethane, AR, Shanghai Test; Acetonitrile, AR, Shanghai Test; Epichlorohydrin, AR, Adamas; Epibromopropane, AR, Adamas.
[0038] The characterization and testing instruments involved in this embodiment are as follows:
[0039] Oil bath, DF-101S, Zhengzhou Great Wall Science & Industry Trade Co., Ltd.; Vacuum drying oven, DZF-150, Zhengzhou Great Wall Science & Industry Trade Co., Ltd.; Analytical balance, YP402N, Shanghai Precision Scientific Instruments Co., Ltd.; Circulating water multi-purpose vacuum pump, SHB-Ⅲ, Zhengzhou Great Wall Science & Industry Trade Co., Ltd.; Infrared spectrometer, Agilent Cary 660, Agilent Technologies Inc.; Thermogravimetric analyzer, DT Q600 V8.2 Build100, PerkinElmer, USA; Nuclear magnetic resonance spectrometer, Brucker 400 MHz, Brucker Biospin, Switzerland; Physical adsorption analyzer, ASAP 2020M, Shanghai Micromeritics Co., Ltd.; Scanning electron microscope, JSM-5610LV, JEOL Ltd., Japan.
[0040] Example 1
[0041] This embodiment describes the preparation of macrocyclic polyamine-based porous organic aerogels. The embodiment of this application is described below with reference to the accompanying drawings.
[0042] See Figure 1 , Figure 1 This embodiment illustrates a preparation process diagram, including the following steps:
[0043] Step 1: Synthesis of 1,4,7,10-tetra(4-vinylbenzyl)-1,4,7,10-tetraazacyclododecane (Tsc)
[0044] Tetraazacyclododecane (2.0 g, 11.6 mmol) was dissolved in acetonitrile (CH3CN, 20 ml) and dichloromethane (CH2Cl2, 20 ml) until fully dissolved. Then, triethylamine (Et3N, 7 ml) was added, followed by 4-chloromethylstyrene (2.0 g, 11.6 mmol). The mixture was heated to 50 °C and stirred for 24 h under a nitrogen atmosphere. During the reaction, a white solid precipitated from the solution. After the reaction was complete, the mixture was filtered to obtain a solid, which was washed repeatedly with ethyl acetate and dried under vacuum to give a white solid, Tsc (6.80 g, yield 90.67%).
[0045] Step 2: Preparation of macrocyclic polyamine porous organic wet gel
[0046] The prepared monomer Tsc (5.24 g, 8.2 mmol) was added to a mixed solvent of chloroform (CHCl3, 3 ml) and tetrahydrofuran (THF, 7 ml). The purified initiator azobisisobutyronitrile (AIBN, 0.15 g, 0.9 mmol) was then added to the mixture, and the mixture was sonicated for 15 minutes. The mixture was then transferred to a reaction vessel and reacted at 80 °C for 24 hours. After the reaction was complete, the resulting wet gel was removed.
[0047] Step 3: Preparation of macrocyclic polyamine porous organic aerogels (PTsc)
[0048] The synthesized wet gel was dried under normal pressure. Figure 2 (a) in the figure is transformed into macrocyclic polyamine porous organic aerogel PTsc ( Figure 2 Figure (b) shows that the wet gel was placed in a ventilated area for 24 hours at room temperature and normal pressure to allow the solvent to evaporate completely, resulting in porous organic aerogel PTsc.
[0049] The PTsc obtained from the above reaction were identified and detected:
[0050] 1) Scanning electron microscopy analysis
[0051] The morphology of the synthesized porous organic aerogel PTsc catalyst was characterized by SEM, and the elemental distribution of PTsc was characterized by EDS mapping. Figure 3 (a) ~ Figure 3 As shown in (d) in the SEM image, the PTsc particles are arranged in a spherical mass with irregular pores between them, exhibiting an irregular particle shape and a relatively loose texture.
[0052] Subsequently, PTSC was analyzed using the mapping element distribution map, such as Figure 3 (e) Figure 3 As shown in (f), it can be clearly seen that the C and N elements are evenly distributed, indicating that the macrocyclic polyamine-functionalized porous organic aerogel was successfully prepared.
[0053] 2) Solid-state carbon NMR spectroscopy
[0054] The structure of PTsc was determined using solid-state carbon NMR spectroscopy. Figure 4 The presence of characteristic functional group vibration peaks can be clearly observed, confirming the successful preparation of the PTsc catalyst.
[0055] 3) N2 adsorption-desorption test
[0056] To investigate the structural parameters of the catalyst's specific surface area, N2 adsorption-desorption experiments were conducted on the catalyst, such as... Figure 5 As shown, both the PTsc catalyst and the reacted catalyst exhibit Type IV N2 adsorption-desorption isotherms, indicating the presence of a mesoporous structure in the catalyst. The PTsc catalyst demonstrates a specific surface area of 16.38 m². 2 g -1 The recovered catalyst (PTsc-ECH) has a specific surface area of only 5.79 m². 2 g -1 The specific surface area decreased slightly. This phenomenon indicates that PTsc underwent a quaternization reaction with the haloepoxide, leading to pore blockage and a decrease in the specific surface area of the catalyst after the reaction.
[0057] 4) CO2 adsorption curve and isochoric adsorption heat
[0058] To investigate the CO2 adsorption performance of the PTsc catalyst, CO2 adsorption tests were conducted on the catalyst at different temperatures. The test results are as follows: Figure 6 As shown, the CO2 adsorption capacity of PTsc is 1.30 mmol / g under conditions of 273 K and 1 atm. Under conditions of 298 K and 1 atm, the CO2 adsorption capacity of PTsc is 0.80 mmol / g. Calculations show that under low CO2 pressure, the CO2 adsorption capacity of PTsc... Qst The value was 23.76 kJ / mol, which is less than 40 kJ / mol, indicating that the adsorption of CO2 by the PTsc catalyst is through physical rather than chemical action.
[0059] 5) Thermogravimetric analysis
[0060] To evaluate the thermal stability of the PTsc catalyst, thermogravimetric analysis was used for testing. Figure 7 The PTsc catalyst exhibited a weight loss (<10%) in the range of room temperature to 100 °C, which was attributed to the evaporation of adsorbed water on the material surface. The cycloaddition reaction temperature involved in this experiment was much lower than the decomposition temperature of the catalyst framework, thus confirming that the PTsc catalyst possesses good thermal stability under the reaction conditions.
[0061] Application Example 1
[0062] In this application example, the organic aerogel from Example 1 is used as a catalyst in the cycloaddition reaction of a haloepoxy substrate with carbon dioxide (CO2).
[0063] 50 mg of catalyst and a magnetic stir bar were loaded into a 25 mL Schlenk tube. The reaction system was evacuated and purged with carbon dioxide, a process repeated three times. Under a carbon dioxide atmosphere, 10 mmol of epichlorohydrin (ECH) was added. Subsequently, the reaction tube was connected to a balloon filled with carbon dioxide, and the epichlorohydrin (ECH) underwent a cycloaddition reaction with CO2 under solvent-free, metal-free, and catalyst-free conditions. After the reaction was carried out for a specified time with stirring at a constant speed, the composition of the reaction mixture was analyzed by 1H NMR spectroscopy, and the substrate conversion and product selectivity were calculated.
[0064] Figure 8 As shown, under the conditions of 100 °C and 24 h of reaction, the yield of epichlorohydrin reached 99% ( Figure 8 (See Figure (a)). Even under milder conditions of 60 °C and 24 h of reaction, a conversion rate of nearly 90% was still achieved. Figure 8 (See Figure (b)). This demonstrates the excellent catalytic performance of the PTsc catalyst in the cycloaddition reaction of haloepoxides with CO2, and also shows that the strategy of using porous organic aerogel catalysts rich in tertiary amine sites to catalyze the synthesis of halocyclic carbonates by quaternizing haloepoxides to generate nucleophiles is feasible.
[0065] After the reaction is complete, the catalyst is separated by filtration and washed with dichloromethane. The catalyst is then dried overnight in a vacuum oven at 60°C and can be directly used in the next catalytic cycle.
[0066] Furthermore, the catalytic performance of PTsc on various haloepoxide substrates was investigated. The substrate was replaced with epichlorohydrin, and other conditions were the same as in the application examples. 1 The conversion and selectivity of each substrate were determined by 1H NMR. For specific catalytic performance data, please refer to [link to relevant documentation]. Figure 9 :contrast Figure 8 and Figure 9 It can be seen that the PTsc catalyst achieves good yields for different haloepoxides, indicating that PTsc possesses certain substrate applicability. One of the more important parameters for evaluating the quality of a catalyst is its catalytic stability. To examine the stability of the PTsc heterogeneous catalyst structure, this catalyst was recycled five times, and the conversion of ECH did not change significantly, with the selectivity remaining above 99%. The recyclability test fully demonstrates that the PTsc catalyst structure possesses excellent cycling stability.
[0067] Application Example 2
[0068] This application example uses the organic aerogel from Example 1 as a thermal insulation material, applying it to building exterior walls, industrial pipelines, and cold chain logistics, where it exhibits excellent thermal insulation performance.
[0069] like Figure 10 As shown: The PTsc aerogel prepared in Example 1 was processed into plates, felts, or granules, and directly bonded or filled onto the surface of the material to be insulated (such as wall interlayers, pipe outer walls, etc.). It was placed in a high-temperature environment of 100 ℃, with an initial temperature of 39.5 ℃ (i.e., Figure 10 In Figure (a), the temperature increases to 56.5 ℃ after 5 min, 61.6 ℃ after 15 min, and decreases slightly to 59.4 ℃ after 30 min. However, it recovers to 62.9 ℃ after 60 min, maintaining the temperature around 60 ℃ for a relatively long period. Its nanoporous structure effectively blocks heat conduction, achieving excellent heat insulation effect.
[0070] The porous aerogel described in this application is mainly used in building exterior walls, industrial pipelines, aerospace equipment, and other fields, often in environments with high or low temperatures or drastic temperature differences. In buildings, it is often combined with decorative panels to form an exterior wall insulation system, while in industrial applications, it is used to wrap pipes and equipment to stabilize internal temperatures. The process balances lightweight design with fire resistance, achieving long-term, high-efficiency thermal insulation.
[0071] The above-described embodiments are merely illustrative of several feasible implementations of the present invention, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the present invention, nor are the embodiments intended to limit the scope of protection in the claims of the present invention. For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention. All equivalent implementations or changes that do not depart from the present invention should be included in the technology of the present invention.
Claims
1. A method for preparing a macrocyclic polyamine-based porous organic aerogel, characterized in that, The steps are as follows: Step 1: Tetraazacyclododecane reacts with chloromethylstyrene to obtain an intermediate; Step two: The intermediate is added to a mixed solvent of chloroform and tetrahydrofuran, and then the initiator azobisisobutyronitrile is added and ultrasonically vibrated. Sol-gel polymerization is carried out at 60~100 °C for 12~30 h to obtain a wet gel. After drying, a macrocyclic polyamine porous organic aerogel is obtained. The structural formula of the intermediate is: , The structural formula of the macrocyclic polyamine porous organic aerogel is: 。 2. The method for preparing a macrocyclic polyamine porous organic aerogel according to claim 1, characterized in that: In step one, the molar ratio of tetraazacyclododecane to chloromethylstyrene is 1:1 to 4.
3. The method for preparing a macrocyclic polyamine porous organic aerogel according to claim 1, characterized in that: In step one, tetraazacyclododecane is dissolved in acetonitrile and dichloromethane, and then triethylamine is added. Under a nitrogen atmosphere, it reacts with chloromethylstyrene to complete the reaction.
4. The method for preparing a macrocyclic polyamine porous organic aerogel according to claim 1, characterized in that: In step one, the reaction temperature is 40~60 ℃ and the reaction time is 20~30 h.
5. The method for preparing a macrocyclic polyamine porous organic aerogel according to claim 1, characterized in that: The drying process is atmospheric pressure drying.
6. The application of macrocyclic polyamine porous organic aerogel prepared by the method of claim 1 as a thermal insulation material in building exterior walls, industrial pipelines or cold chain logistics.
7. The application of the macrocyclic polyamine porous organic aerogel prepared by the method of claim 1 as a catalyst in the cycloaddition reaction of haloepoxide substrates with carbon dioxide.
8. The application according to claim 7, characterized in that: The halogenated epoxy substrate is epichlorohydrin or epibromopropane.