CN105504332A - Preparation method of porous organic polymer integral material - Google Patents

Abstract

The present invention relates to the preparation of a porous organic polymer monolithic material based on the mercapto-epoxy click chemical reaction, specifically, the polyepoxy monomer 2,2ˊ,2〞,2〞ˊ-[1,2-diethylene Methyltetrakis (4,1-phenylene methylene oxide)] tetraphenylolethane?glycidyl?ether, TPEGE, organic multimercapto crosslinking agent, porogen and catalyst were mixed and ultrasonically dissolved, and then dissolved in After a thiol-epoxy?click?reaction occurs at a certain temperature, the porous organic polymer monolithic material can be prepared in one step. The preparation method has the advantages of simple and fast operation, strong versatility, etc., and can prepare a series of different organic polymer monolithic materials according to different application requirements.

Description

A kind of preparation method of porous organic polymer monolithic material

technical field

The invention relates to the preparation of a porous organic polymer monolithic material based on mercapto-epoxy click chemical reaction, specifically mixing polyepoxy organic monomers, organic dimercapto or polymercapto crosslinking agents, porogens and catalysts with ultrasonic After uniformity, the organic polymer monolithic material with a specific porous structure is prepared in one step by using a thiol-epoxy click reaction.

Background technique

Porous monolithic materials have the characteristics of easy preparation, strong modifiability, and good permeability, and are attracting more and more attention, and have been widely used in the field of chromatographic separation and analysis. According to different chemical properties, porous monolithic materials can be divided into three categories, namely organic monolithic materials, inorganic monolithic materials and organic-inorganic hybrid monolithic materials. Among them, inorganic and organic-inorganic hybrid monolithic materials have the characteristics of good mechanical properties and strong resistance to organic solvents, but they also have disadvantages such as poor pH stability, and their preparation processes are relatively cumbersome, requiring more time and manpower. , thus also affecting their preparation reproducibility. In contrast, organic polymer monolithic materials were the first to appear and are currently used more widely. It has the advantages of good pH stability, simple preparation, convenient adjustment of internal pore properties and the like. However, there are also disadvantages such as poor mechanical properties and easy swelling in organic solvents. Moreover, due to the inhomogeneity of its internal pores, its column efficiency in liquid chromatography applications, especially for the separation of small molecular compounds, is far lower than that of packed columns and other two monolithic columns. Therefore, it is urgent to develop a new method for the preparation of organic polymer monoliths with better stability and more uniform internal pores.

At present, free radical polymerization (freeradicalpolymerization) is the most commonly used polymerization method in the preparation of organic polymer monolithic materials. Although this polymerization method has a fast reaction rate, due to its relatively fast and disordered phase separation process, the microstructure of the prepared monolithic material is often irregular, and there will be more micron-sized spherical particles in the internal pores, thus As a result, the permeability of the overall material is poor, and there is a significant eddy diffusion phenomenon in the chromatographic separation, which seriously affects its separation effect. After years of research by many scientific researchers, many different methods have been developed such as ring-opening polymerization (ring-opening polymerization) and controllable living radical polymerization (controllable living radical polymerization) to replace traditional free radical polymerization. Preparation of organic polymer monoliths. Although these methods can overcome the deficiencies of traditional free radical polymerization to a certain extent, most of them have problems such as slow reaction speed, harsh experimental conditions, and cumbersome operation process, so they have not been widely used.

Click chemical reactions, especially those based on thiol groups, have been widely used in the synthesis of new compounds, the preparation of polymers and hydrogels, and the surface of materials due to their good selectivity, mild conditions, and high yields. modification etc. As a typical thiol-based click chemical reaction, the thiol-epoxy click chemical reaction has been widely used in industry and biomedicine because of its high reaction efficiency and easy operation. Surprisingly, however, the application of this reaction in the synthesis of macromolecular polymers is still relatively small, and the application in the preparation of porous polymer monolithic materials has not yet been seen in relevant patents or literature reports.

In order to further improve the stability of the porous organic polymer overall material and effectively improve the inhomogeneity of its internal microstructure, the present invention has developed a method based on thiol-epoxy click reaction to prepare porous organic polymer A new approach to monolithic materials. The organic polymer monolith material prepared by the method not only has a highly ordered three-dimensional skeleton structure, but also has high mechanical strength and good permeability. In addition, the method also has the following characteristics: 1. The preparation steps are more convenient; 2. It has strong versatility and can be applied to various organic polythiol crosslinking agents, and the reaction conditions for different organic crosslinking agents are relatively close; 3. The preparation process It takes a short time, and the preparation can be completed within 6 hours; 4. The reaction conditions are mild, easy to control, and have good reproducibility; 5. The prepared porous monolithic material is easy to carry out subsequent surface modification to meet more and different practical application requirements.

Contents of the invention

The purpose of the present invention is to prepare a series of porous organic polymer monolithic materials with highly ordered pore structures more easily and quickly, and at the same time make the prepared organic polymer monolithic materials have high stability and modifiability, so that Further subsequent modifications are carried out to meet different practical application requirements.

To achieve the above object, the technical solution adopted in the present invention is:

2,2',2",2"'-[1,2-bis-dimethylene tetrakis(4,1-phenylene methylene oxide)]tetraphenylolethaneglycidylether (TPEGE) as polycyclic Oxygen monomers, by choosing different organic polythiol crosslinking agents (such as 1,6-hexanedithiol (1,6-hexanedithiol, HDT) or trimethylolpropane tris (3-mercaptopropionate) (trimethylolpropanetris (3-mercaptopropionate), TPTM) or pentaerythritoltetrakis (3-mercaptopropionate), PTM)) and adjusting the porogenic system to prepare a series of porous organic polymer monoliths with different physical and chemical properties Material. Moreover, the porous organic polymer monolith material prepared by this method has strong modifiability, and its surface can be modified by physical adsorption or chemical bonding to meet the needs of different practical applications.

Preparation of organic polymer porous monolith based on mercapto-epoxy click chemical reaction: mix polyepoxy organic monomers, organic dimercapto or polymercapto crosslinking agents, porogens and catalysts, and then ultrasonically homogenize and remove the dissolved After oxygen, the porous organic polymer monolithic material with highly ordered pore structure is prepared in one step by using thiol-epoxy click reaction.

The specific process is as follows:

1) add 40mg many epoxy organic monomers in reaction vessel;

2) adding an organic dimercapto or polymercapto crosslinking reagent to the reaction vessel, so that the molar (mol) ratio of the organic crosslinking reagent to the polyepoxy organic monomer is 4:1-1:4;

3) Add 80-320 μL of dimethylsulfoxide (DMSO), 0-80 μL of polyethylene glycol (PEG200) (preferably 10-80 μL) and 0-50 μL of water (H ₂ O) into the reaction vessel (preferably 5-50 μL);

4) Add 0-25 mg of porogen polyethylene glycol 10,000 (PEG10,000) to the reaction vessel;

5) Add 2-15 μL of catalyst to the reaction vessel;

6) Ultrasound the above mixed system at room temperature for 20-30 minutes to completely dissolve it to form a uniform transparent solution, and remove the dissolved oxygen therein;

7) introducing the mixed solution obtained in step 6) into the container and sealing;

8) Place the container containing the mixed solution obtained in step 7) at 40-120°C to react until a solid is formed;

9) Rinse the above-mentioned monolithic material with methanol to remove porogens and unreacted or unbound substances to obtain a porous hybrid monolithic material with organic functional groups.

The in-situ preparation process of the porous organic polymer monolithic material based on the mercapto-epoxy click chemical reaction of the present invention is schematically shown as follows:

The reaction vessel used in the steps 1), 2), 3), 4), 5) and 6) is a centrifuge tube; the polyepoxy organic monomer used in the step 1) is 2,2', 2″, 2″'-[1,2-bis-dimethylene tetrakis(4,1-phenylene methylene oxide)]tetraphenylolethaneglycidylether (TPEGE); used in the step 2) The organic dimercapto or polymercapto crosslinking agent is 1,6-hexanedithiol (1,6-hexanedithiol, HDT) or trimethylolpropane tris (3-mercaptopropionate) (trimethylolpropanetris (3-mercaptopropionate) ), TPTM) or pentaerythritol tetrakis-3-mercaptopropionate (pentaerythritoltetrakis (3-mercaptopropionate), PTM); the catalyst adopted in the step 5) is a concentration of 0.25mol/L KOH aqueous solution; the step 7 ) The container used is a capillary tube or a conventional liquid chromatography column or a centrifuge tube; the reaction time in the step 8) is 2-6 hours.

This method uses a thiol-epoxy click reaction, although it is not sensitive to the presence of dissolved oxygen in the system, but in order to avoid its impact on the morphology of the prepared porous monolithic material, before the reaction starts, Deoxygenation is best. The formation of this monolithic material only needs to be reacted at one temperature, and porous monolithic materials with different morphologies can be prepared by adjusting the reaction temperature.

The method is based on the thiol-epoxy click reaction to prepare porous monolithic materials. Therefore, the reaction efficiency is very high, and the preparation of porous monolithic materials can be completed in a short time. The raw material conversion rate of the method is very high, so that the prepared porous organic polymer monolithic material has a higher degree of crosslinking, and therefore has higher stability than the organic monolithic material prepared by free radical polymerization before. In addition, the prepared porous monolith has a highly ordered three-dimensional framework structure, and its pore size and pore structure can be changed by changing the ratio of polyepoxy monomer/multimercapto crosslinking agent, or the composition of porogenic solvent, or porogenic The contents of reagents and catalysts, or the reaction temperature are regulated.

The hybrid monolithic material prepared by the invention has a highly ordered three-dimensional skeleton structure and is very suitable for chromatographic separation and analysis. The results of liquid chromatographic investigation show that the properties exhibited are consistent with the chromatographic retention properties of the epoxy monomer and organic polymercapto crosslinking agent used. In this experiment, different organic polythiol crosslinking agents were selected, and the preparation method can successfully prepare porous organic polymer monolithic materials, and all exhibit the same chromatographic retention characteristics as the added organic functional monomers. The hydrophobicity exhibited by the obtained porous monolithic column as prepared increases with the increase of the hydrophobicity of the polymercapto cross-linking agent.

Description of drawings

Figure 1 shows the chromatographic separation results of benzene series on a TPEGE-PTM organic polymer monolithic column.

Fig. 2 is a pore size distribution diagram of TPEGE-PTM organic polymer monolithic material.

detailed description

Example 1

1. Add 40mg of TPEGE to the centrifuge tube.

2. Add 26 mg of PTM to the above centrifuge tube.

3. Add 160 μL of DMSO, 40 μL of PEG200 and 20 μL of H ₂ O to the above centrifuge tube.

4. Add 10 mg of porogen PEG10,000 into the centrifuge tube.

5. Add 5 μL of catalyst (aqueous KOH solution with a concentration of 0.25 mol/L) into the reaction vessel.

6. Ultrasonicate the centrifuge tube at room temperature for 20 minutes to mix the components in it evenly, and remove the dissolved oxygen in it.

7. Introduce the prepolymerized solution obtained in step 6 into a capillary tube of 75 μm (inner diameter) that has been pre-sulfhydrylized with a syringe, then seal both ends of the capillary with silica gel, and then seal the centrifuge tube containing the remaining prepolymerized solution Membrane seal.

8. Put the capillary and centrifuge tube in step 7 in a water bath at 50°C and react for 4 hours. At this time, the prepolymerization solution in the centrifuge tube has formed a yellow solid.

9. Rinse the capillary with methanol and water to wash out the porogen and some unreacted substances to obtain the capillary organic monolithic column. For those in the centrifuge tube, soak and wash repeatedly with methanol and water to obtain organic monolithic materials.

Figure 1 is the capillary liquid chromatography separation results of benzene series on TPEGE-PTM organic polymer monolithic column. The chromatographic conditions were acetonitrile/water (60/40, v/v), and the flow rate was 240nL/min. The peaks in the chromatogram are 1: benzene, 2: toluene, 3: ethylbenzene, 4: propylbenzene, 5: butylbenzene, and the order of the peaks is from weak to strong hydrophobicity, which is a typical reversed-phase chromatography. mechanism. On the one hand, its retention is determined by the hydrophobic characteristics of TPEGE, and on the other hand, it is determined by the organic polythiol crosslinking agent PTM used. After calculating its column efficiency, it is found that the column efficiency of the column for the above five compounds is above 100,000N/m, and the highest can reach 132,000N/m (benzene). It is much higher than the column efficiency of all organic polymer monolithic columns reported by free radical polymerization before, and even higher than that of most inorganic monolithic columns and organic-inorganic hybrid monolithic columns. This shows that the method introduced in the present invention can be used to rapidly prepare a capillary organic polymer monolithic column with high separation performance.

Fig. 2 is a pore size distribution diagram of TPEGE-PTM organic polymer monolithic material. It can be seen from Figure 2 that the pore size distribution of the monolithic material is very narrow, indicating that the pore structure inside the organic polymer monolithic material is highly ordered and the pore size is relatively uniform, which also proves that the thiol-epoxy click reaction can be used For the preparation of porous organic polymer monoliths with highly ordered three-dimensional framework structures.

Example 2

1. Add 40mg of TPEGE to the centrifuge tube.

2. Add 27 mg of TPTM to the above centrifuge tube.

3. Add 160 μL of DMSO, 40 μL of PEG200 and 20 μL of H ₂ O to the above centrifuge tube.

4. Add 15 mg of porogen PEG10,000 into the centrifuge tube.

5. Add 5 μL of catalyst (aqueous KOH solution with a concentration of 0.25 mol/L) into the reaction vessel.

6. Ultrasonicate the centrifuge tube at room temperature for 20 minutes to mix the components in it evenly, and remove the dissolved oxygen in it.

7. Introduce the prepolymerized solution obtained in step 6 into a capillary tube of 75 μm (inner diameter) that has been pre-sulfhydrylized with a syringe, then seal both ends of the capillary with silica gel, and then seal the centrifuge tube containing the remaining prepolymerized solution Membrane seal.

8. Put the capillary and centrifuge tube in step 7 in a water bath at 60°C and react for 4 hours. At this time, the prepolymerization solution in the centrifuge tube has formed a yellow solid.

9. Rinse the capillary with methanol and water to wash out the porogen and some unreacted substances to obtain a capillary hybrid monolithic column. For those in the centrifuge tube, soak and wash repeatedly with methanol and water to obtain the hybrid monolithic material.

By carrying out chromatographic evaluation to the TPEGE-TPTM organic polymer monolithic column, it is found that it is also very good for the separation effect of small molecular compounds, and the column efficiency can reach 128,000N/m (propyl benzene), which further proves the method introduced in the present invention Efficiency and stability in the preparation of capillary organic polymer monolithic columns with high separation performance. In addition, comparing the specific operation process of Example 1 and Example 2, it can be found that different organic polymercapto crosslinking agents are used, but there is no obvious difference between the two in terms of the ratio of the pre-polymerization solution or the specific operation. The difference is exactly that the porogen PEG10000 of 5mg has been added more in embodiment 2 than embodiment 1 and has improved reaction temperature. This shows that the method introduced in the present invention has high versatility, and can easily replace reagents and adjust the ratio to prepare monolithic materials with different properties to meet different practical application requirements.

Claims (7)

1. a preparation method for porous organic polymer integral material, is characterized in that: its process is as follows,

1) in reaction vessel, 40mg multi-epoxy organic monomer is added;

2) in reaction vessel, adding organic dimercapto or many sulfydryls cross-linking reagent, making mole (mol) of organic cross-linking reagent and multi-epoxy organic monomer than being 4:1-1:4;

3) in reaction vessel, the dimethyl sulfoxide (DMSO) (dimethylsulfoxide, DMSO) of 80-320 μ L is added, the polyoxyethylene glycol (PEG200) of 0-80 μ L and the water (H of 0-50 μ L ₂o);

4) in reaction vessel, add the pore-creating agent polyoxyethylene glycol 10,000 (PEG10,000) of 0-25mg;

5) in reaction vessel, add the catalyzer of 2-15 μ L;

6) by above-mentioned mixed system at normal temperatures ultrasonic 20-30min make it dissolve completely to form the solution of homogeneous transparent, and removing dissolved oxygen wherein;

7) by step 6) in the mixing solutions that obtains to be incorporated in container and to seal;

8) by step 7) in the container filling mixing solutions that obtains be placed in 40-120 DEG C at reaction, until form solid;

9) with washed with methanol above-mentioned integral material, with the material removing pore-creating agent and unreacted or do not combine, the porous organic polymer integral material with organo-functional group is obtained.

2. method according to claim 1, is characterized in that: described step 1), 2), 3), 4), 5) and 6) in reaction vessel used be centrifuge tube.

3. method according to claim 1, it is characterized in that: described step 1) in adopt multi-epoxy organic monomer be 2,2', 2 "; 2 " '-[1,2-ethanetetrayl four (4,1-phenylene methylene oxygen)] tetraoxane (tetraphenylolethaneglycidylether, TPEGE).

4. method according to claim 1, it is characterized in that: described step 2) in adopt organic dimercapto or many thiol crosslinkers be 1,6-ethanthiol (1,6-hexanedithiol, or trimethylolpropane tris (3-mercaptopropionic acid ester) (trimethylolpropanetris (3-mercaptopropionate) HDT), or tetramethylolmethane four-3-mercaptopropionic acid ester (pentaerythritoltetrakis (3-mercaptopropionate), PTM) TPTM).

5. method according to claim 1, is characterized in that: described step 5) in the KOH aqueous solution of the catalyzer that adopts to be concentration be 0.25mol/L.

6. method according to claim 1, is characterized in that: described step 7) in container used be kapillary or conventional liquid phase chromatographic column or centrifuge tube.

7. method according to claim 1, is characterized in that: described step 8) in reaction times be 2-6 hour.