Preparation method of organic silicon hybrid porous resin microspheres for liquid chromatography, microspheres and application

Abstract

The present application relates to a kind of organic silicon hybrid porous resin microspheres for liquid chromatography, the resin microspheres are polydivinyl benzene-g-methacryloyl oxy propyl trimethoxysilane porous resin microspheres, specifically, the copolymer of divinyl benzene and g-methacryloyl oxy propyl trimethoxysilane, and the particle size of microsphere is 30-40 μm.The specific surface area of original microsphere is 600-900 m 2 / g, and the specific surface area can reach 1000-1200 m 2 / g after crosslinking treatment.The resin microspheres of the present application are prepared by suspension polymerization method, which is simple and easy to scale up.The prepared original microspheres have good mechanical strength and contain a large number of reaction sites for modification, which can be modified according to different needs and suitable for different separation systems.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of liquid chromatography column matrix, in particular to a silicone hybrid porous resin microsphere applied to liquid chromatography and a preparation method thereof. BACKGROUND

[0002] As one of the most commonly used methods in modern analytical chemistry, high performance liquid chromatography (HPLC) has the advantages of high efficiency, rapidness, high sensitivity, etc., and can be used in many scientific fields such as quality control, drug analysis, clinical testing, environmental monitoring, etc. The separation principle of HPLC is based on the difference in affinity of the compounds to be separated to the stationary phase and the mobile phase, so the chromatographic column is the core of the liquid chromatography system, and the research on the chromatographic packing material becomes the most abundant, most dynamic and most creative part of the chromatographic research.

[0003] Liquid chromatography packing materials can be mainly divided into inorganic silica gel matrix, organic polymer matrix and organic-inorganic hybrid matrix. The silica gel matrix has high mechanical strength, good thermal stability and easy-to-control pore structure. However, the silica gel matrix has a narrow pH tolerance range, and there is a risk of dissolution when used in alkaline mobile phase.

[0004] The organic polymer matrix can be roughly divided into polyacrylamide, polystyrene and polymethacrylate, and the most widely used is polystyrene. Compared with the silica gel matrix, the polymer matrix has a wide pH application range, i.e. the chromatographic performance will not be affected even if the chromatographic column is flushed with strong alkali solution such as sodium hydroxide. However, the organic polymer has its fatal disadvantage, i.e. poor mechanical strength and cannot withstand high column pressure in terms of its physical and chemical properties.

[0005] To solve the problem of poor mechanical strength, the most common method is to prepare organic-inorganic hybrid polymers by mixing organic polymers with silicon-containing reagents. A method for preparing an organic-inorganic hybrid polymer monolithic column with hydrophilic properties using vinyltrimethoxysilane, methyl orthosilicate and acrylamide is disclosed in Analytical Chemistry, 2009, 81(9), 3529-3536 (non-patent document 1); a method for preparing a hybrid monolithic column with strong anion exchange properties using vinyltrimethoxysilane, methyl orthosilicate and N,N,N-trimethyl-3-(2-methylallyl amido)-1- propylammonium chloride as precursors is disclosed in Analytical Chemistry, 2010, 82(7), 2907-2915 (non-patent document 2); a method for preparing a hybrid monolithic column with boronic acid affinity properties using 3-(methacryloyloxy)propyltrimethoxysilane, methyl orthosilicate and 4-vinylphenylboronic acid as precursors is disclosed in Chemical Communications, 2011, 47(34), 9675-9677 (non-patent document 3); a method for preparing a hybrid monolithic column with strong cation exchange and reversed-phase retention mechanisms using mercaptopropyltrimethoxysilane, methyl orthosilicate and 3-sulfopropyl methacrylate potassium as precursors is disclosed in Electrophoresis, 2013, 34(4), 510-517 (non-patent document 4); a method for synthesizing a cyclodextrin derivative hybrid monolithic column using a cyclodextrin derivative containing a double bond as an organic monomer, vinyltrimethoxysilane and methyl orthosilicate is disclosed in Analytical Chemistry, 2011, 83(9), 3616-3622 (non-patent document 5).

[0006] In the preparation of organic-inorganic hybrid polymer microspheres, a method for preparing non-porous organic-inorganic hybrid polymer microspheres for ion chromatography using styrene and 3-trimethoxysilylpropyl methacrylate is disclosed in patent document (application number 201110263262.3). However, since non-porous microspheres have a separation effect inferior to that of porous materials in actual sample chromatographic separation, a simple synthesis method is needed to prepare high-strength porous organic-inorganic hybrid polymer microspheres. SUMMARY

[0007] Therefore, the technical problem to be solved by the present application is to provide a method for preparing organic-silicon hybrid resin microspheres for liquid chromatography. Another technical problem to be solved by the present application is to provide microspheres prepared by the method. Another technical problem to be solved by the present application is to provide applications of the microspheres.

[0008] The technical scheme of the present application is a preparation method of silicone hybrid porous resin microspheres for liquid chromatography, which is a suspension polymerization method and comprises the following steps:

[0009] (1) Add dispersant and stabilizer into water at 50-70°C and stir to dissolve; the mass fraction of the dispersant and the stabilizer is 0.5%-2%; the dispersant is selected from one or more than one of the following components: sodium docusate, gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium dodecyl sulfate, hydroxyethyl cellulose, hydroxypropyl cellulose, and sodium dodecyl benzene sulfonate; the stabilizer is selected from one or more than one of the following components: sodium docusate, gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium dodecyl sulfate, hydroxyethyl cellulose, hydroxypropyl cellulose, and sodium dodecyl benzene sulfonate;

[0010] (2) Take a certain amount of xylene, divinylbenzene, γ-methacryloyloxypropyl trimethoxysilane and azobisisobutyronitrile and mix them uniformly;

[0011] The volume ratio of divinylbenzene and γ-methacryloyloxypropyl trimethoxysilane is 7:3-9:1, the amount of xylene is 1.5-3 times the sum of the volumes of divinylbenzene and γ-methacryloyloxypropyl trimethoxysilane; the amount of azobisisobutyronitrile is 0.5%-1.5% of the total mass of the comonomers; the total mass of the comonomers is the sum of the masses of divinylbenzene monomers and γ-methacryloyloxypropyl trimethoxysilane monomers;

[0012] (3) Add the organic phase mixed uniformly in step (2) into the reactor in step (1), wherein the volume ratio of the total volume of the organic phase to the volume of water is 1:3-1:5; react for 10-50 minutes, then continue to heat to 70-80°C and continue to react for 8-12 hours, and finally wash the microspheres with hot water and ethanol respectively;

[0013] (4) Add the microspheres obtained in step (3) into tetrahydrofuran and ultrasonic for 1-30 minutes, then continue to swell for 10-14 hours; the ratio of the microspheres to tetrahydrofuran is 1:10-1:15 (g / mL);

[0014] (5) Add ammonia water into the reaction bottle in step (4), stir thoroughly, stand still, and finally wash the microspheres with water and ethanol.

[0015] In step (1), the dispersant can be selected in multiple ways, which mainly affects the particle size of the microspheres; different dispersants can be selected according to the size of the target microspheres; the stabilizer also has multiple choices, but relatively speaking, gelatin has better stability in maintaining the morphology of the microspheres; the dispersant and the stabilizer are generally not clearly distinguished, and many substances are both dispersants and stabilizers; the effects are better when different substances are used as the dispersant and the stabilizer.

[0016] In step (2), the four components are mutually soluble organic phases, in step (3), the organic phases are added to the water phase of step 1, and the final reaction system is a two-phase mixed system of organic phase / water phase. The preparation method of the microspheres is essentially a free radical heat-induced polymerization reaction, and the comonomer is a monomer with unsaturated bonds, which grows into a chain through polymerization, and further obtains the final polymer microspheres; azobisisobutyronitrile is used as a free radical initiator, which functions to initiate the polymerization reaction, and the amount of azobisisobutyronitrile will affect the particle size and particle size distribution of the final microspheres, so a suitable amount is required. The silane monomer and divinylbenzene monomer are both comonomers.

[0017] In step (3), the microspheres are first washed with hot water and then washed with ethanol.

[0018] According to the preparation method of the organic silicon hybrid porous resin microspheres for liquid chromatography, preferably, the reaction time in step (3) is 30-50 minutes.

[0019] According to the preparation method of the organic silicon hybrid porous resin microspheres for liquid chromatography, preferably, the stirring in step (5) is ultrasonic stirring, and the ultrasonic stirring is performed for 15-30 minutes; and the standing time in step (5) is 18-36 hours.

[0020] According to the preparation method of the organic silicon hybrid porous resin microspheres for liquid chromatography, preferably, in step (5), the volume ratio of the ammonia water to the tetrahydrofuran is 1:15-1:20.

[0021] According to the preparation method of the organic silicon hybrid porous resin microspheres for liquid chromatography, preferably, after step (5), a post-crosslinking method is further included; the post-crosslinking method includes the following steps:

[0022] The microspheres are dispersed in 1,2-dichloroethane for swelling for 6-10 hours, anhydrous ferric chloride is added, and then the temperature is raised to 70-90°C for reaction for 7-9 hours; after the reaction is completed, the microspheres are washed with ethanol, washed with dilute hydrochloric acid, and then washed with water until neutral, and then dried to obtain the target product.

[0023] Further, the mass ratio of 1,2-dichloroethane, anhydrous ferric chloride, and the microspheres is 4-7:0.2-0.5:0.5-2.

[0024] The application further provides the microspheres obtained by the preparation method of the organic silicon hybrid porous resin microspheres for liquid chromatography, and the microspheres are copolymers of divinylbenzene and γ-methacryloyloxypropyltrimethoxysilane; the specific surface area of the obtained original microspheres is 600-900 m 2 / g, and the pore volume is 0.8-1.4 cm3 / g, average pore size 5-8 nm. The microspheres have good thermal stability and can withstand pressure of at least 3500 psi. The mechanical strength of the microspheres after cross-linking treatment is obviously better as compared from the pressure-flow rate graph in the drawing.

[0025] The present application also provides another method for preparing the silicone hybrid porous resin microspheres for liquid chromatography, and the microspheres obtained by the method have specific surface area of 1000-1200 m 2 / g, pore volume 1.2-1.8 cm 3 / g, average pore size 5-8 nm. The microspheres have good thermal stability and can withstand pressure of at least 3500 psi. The mechanical strength of the microspheres after cross-linking treatment is obviously better as compared from the pressure-flow rate graph in the drawing.

[0026] Preferably, the particle size of the microspheres is 30-40 μm.

[0027] The present application provides the use of the above-mentioned microspheres in liquid chromatography. In particular, the use as liquid chromatography packing material.

[0028] The present application specifically provides the preparation and use of polydivinylbenzene-γ-methacryloxypropyltrimethoxysilane porous resin microspheres.

[0029] The prepared microspheres are all porous resin microspheres. By adding silane monomers, since the silane monomers also contain unsaturated bonds, they can be copolymerized with divinylbenzene monomers to form polymers, so that the polymer skeleton contains silicon elements, which can improve the mechanical strength of the resin microspheres. By adjusting the ratio of silane monomers to divinylbenzene monomers, the final resin microspheres can have appropriate specific surface area and good mechanical strength. On the other hand, the resin microspheres obtained by the final polymerization contain a large number of siloxane bonds in the skeleton, which are prone to condensation reaction, so that the long chains of polymers in the skeleton can form new chemical bonds between each other, i.e. the cross-linking degree is improved, and at the same time the mechanical strength of the resin microspheres is further improved. The preparation method is simple and easy to scale up. At the same time, the microspheres contain a large number of reaction sites for modification, which can be modified according to different separation systems. Since the monomer used is divinylbenzene, the activity of the two unsaturated bonds is different, which can lead to a large number of unreacted carbon-carbon double bonds in the skeleton of the final resin microspheres. Under the catalysis of Lewis acid, the long chains of polymers in the skeleton can form new chemical bonds between each other through the Friedel-Crafts alkylation reaction, which further improves the cross-linking degree and the specific surface area and mechanical strength of the resin microspheres. The resin microspheres can be used in alkaline environment for a long time, and can be used as the preferred matrix in the environment where silica gel matrix is not suitable.

[0030] The two main points of the prepared porous resin microspheres in the present application are the porous structure and the better mechanical strength. The mechanical strength effect can be seen from the multiple pressure-flow rate graphs in the drawings. The linear relationship between pressure and flow rate proves that the resin microspheres can withstand the tested pressure. At the same time, the resin microspheres are involved in the process of loading the resin microspheres into the chromatographic column in the application of chromatography. After the completion of the loading, the resin microspheres with different mechanical strengths will show different pressures at the same flow rate when used in liquid chromatography. The slightly weaker mechanical strength will show a higher pressure, that is, the linear relationship in the pressure-flow rate graph has a larger slope. By comparing the slope, the mechanical strength difference between different resin microspheres can be compared. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 Thermogravimetric curve of the resin microspheres prepared for Example 1.

[0032] Figure 2 Scanning electron microscope graph of the resin microspheres prepared for Example 1.

[0033] Figure 3 Thermogravimetric curve of the resin microspheres prepared for Example 4.

[0034] Figure 4 Scanning electron microscope graph of the resin microspheres prepared for Example 4.

[0035] Figure 5 Flow rate and column pressure relationship graph of the chromatographic column loaded for Example 7.

[0036] Figure 6 Flow rate and column pressure relationship graph of the chromatographic column loaded for Example 8.

[0037] Figure 7 Flow rate and column pressure relationship graph of the chromatographic column loaded for Example 9.

[0038] Figure 8 Chromatogram of the separation and purification of stevia extract for Example 10, Figure 8 The left and right two graphs are respectively Figure 8 a and Figure 8 b. DETAILED DESCRIPTION

[0039] The following provides a specific embodiment of the preparation method of the silicone hybrid porous resin microspheres for high performance liquid chromatography in the present application.

[0040] Example 1

[0041] Step (1) In a 2000 mL three-necked flask, 1080 mL of pure water, 5.4 g of sodium docusate and 5.4 g of gelatin were added, and stirred at 70°C for 20 minutes to completely dissolve the sodium docusate and the gelatin;

[0042] Step (2) Take another beaker, add 240 mL of xylene, 108 mL of divinylbenzene, 12 mL of γ-methacryloyloxypropyltrimethoxysilane and 0.6 g of AIBN, mix well;

[0043] Step (3) Add the well-mixed organic phase in (2) to (1), react at 70°C for 40 minutes, then increase the temperature to 80°C and continue to react for 8 hours. After the reaction is completed, wash the microspheres with hot water, then with ethanol, and finally dry to obtain the microspheres;

[0044] Step (4) Take 60 g of the microspheres prepared in (3), disperse them in 600 mL of tetrahydrofuran and ultrasonic for 15 minutes, then stand for 12 hours for swelling;

[0045] Step (5) Add 30 mL of ammonia water, ultrasonic and stir for 15 minutes, then stand for 24 hours, after the reaction is completed, wash with water and ethanol, and finally dry to obtain the target product;

[0046] Using specific surface area analyzer for analysis, the specific surface area is 811 m 2 / g, the pore volume is 1.32 cm 3 / g, and the average pore size is 7.11 nm;

[0047] Using thermal gravimetric analyzer for analysis, the result is as Figure 1 , and the decomposition temperature of the microspheres is 287°C;

[0048] Using scanning electron microscope for analysis, the result is as Figure 2 , and the average particle size is 33 μm.

[0049] Example 2

[0050] In step (2) of Example 1, 108 mL of divinylbenzene and 12 mL of γ-methacryloyloxypropyltrimethoxysilane are replaced by 96 mL of divinylbenzene and 24 mL of γ-methacryloyloxypropyltrimethoxysilane, and the other steps are operated according to Example 1. Using specific surface area analyzer for analysis, the specific surface area is 747 m 2 / g, the pore volume is 1.09 cm 3 / g, and the average pore size is 6.27 nm.

[0051] Example 3

[0052] In step (2) of Example 1, 108 mL of divinylbenzene and 12 mL of γ-methacryloyloxypropyltrimethoxysilane are replaced by 84 mL of divinylbenzene and 36 mL of γ-methacryloyloxypropyltrimethoxysilane, and the other steps are operated according to Example 1. Using specific surface area analyzer for analysis, the specific surface area is 639 m2 / g, and the pore volume was 0.88 cm 3 / g, and the average pore size was 5.60 nm.

[0053] Example 4

[0054] The 50 g of the microspheres prepared in Example 1 were dispersed in 275 mL of 1,2-dichloroethane and allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80°C for 8 h under nitrogen protection. After the reaction, the product was washed with ethanol, then washed with dilute hydrochloric acid several times, washed with water until neutral, and finally dried to obtain the target product.

[0055] The specific surface area analyzer was used for analysis, and the specific surface area was 1071 m 2 / g, and the pore volume was 1.76 cm 3 / g, and the average pore size was 7.51 nm.

[0056] The thermal gravimetric analyzer was used for analysis, and the results were as follows Figure 3 The decomposition temperature of the microspheres was 276°C.

[0057] The scanning electron microscope was used for analysis, and the results were as follows Figure 4 The average particle size was 33 μm.

[0058] Example 5

[0059] The 50 g of the microspheres prepared in Example 2 were dispersed in 275 mL of 1,2-dichloroethane and allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80°C for 8 h under nitrogen protection. After the reaction, the product was washed with ethanol, then washed with dilute hydrochloric acid several times, washed with water until neutral, and finally dried to obtain the target product. The specific surface area analyzer was used for analysis, and the specific surface area was 1079 m 2 / g, and the pore volume was 1.49 cm 3 / g, and the average pore size was 6.39 nm.

[0060] Example 6

[0061] The 50 g of the microspheres prepared in Example 3 were dispersed in 275 mL of 1,2-dichloroethane and allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80°C for 8 h under nitrogen protection. After the reaction, the product was washed with ethanol, then washed with dilute hydrochloric acid several times, washed with water until neutral, and finally dried to obtain the target product. The specific surface area analyzer was used for analysis, and the specific surface area was 1019 m 2 / g, and the pore volume was 1.22 cm 3 / g, and the average pore size was 5.57 nm.

[0062] Example 7

[0063] The microspheres obtained from step (3) in Examples 1, 2, 3 and polydivinylbenzene microspheres were packed into 4.6 x 250 i.d. mm stainless steel chromatographic columns by homogenization method, and the column pressure at different flow rates was recorded using ethanol as the mobile phase to obtain Figure 5 . By comparison, it can be seen that after the addition of silane, the chromatographic column shows lower column pressure under the same mobile phase, proving good mechanical strength.

[0064] Example 8

[0065] The final microspheres obtained from step (5) in Examples 1, 2, 3 were packed into 4.6 x 250 i.d. mm stainless steel chromatographic columns by homogenization method, and the column pressure at different flow rates was recorded using isopropanol as the mobile phase to obtain Figure 6 . By comparison, it can be seen that after the silane is cross-linked by hydrolysis and condensation, the column pressure is lower than that without cross-linking, proving that the mechanical strength is further improved after hydrolysis and condensation cross-linking.

[0066] Example 9

[0067] The microspheres obtained in Examples 4, 5, 6 were packed into 4.6 x 250 i.d. mm stainless steel chromatographic columns by homogenization method, and the column pressure at different flow rates was recorded using 50% isopropanol aqueous solution as the mobile phase to obtain Figure 7 . By comparison, it can be seen that after post-crosslinking treatment, the chromatographic column shows lower column pressure, proving that post-crosslinking can further improve the mechanical strength.

[0068] Example 10

[0069] The 4.6 x 250 i.d. mm stainless steel chromatographic column packed with the microspheres prepared in Example 5 was used to separate and purify the actual sample stevia extract, and the results are shown in Figure 8 . By analyzing component B, it can be seen that the content of rebaudioside A is increased from 26.14% to 58.53%, having certain separation and purification capacity.

[0070] Figure 8 (a) The chromatographic column used for preparation was a 4.6 x 250 i.d. mm stainless steel chromatographic column packed with the microspheres prepared in Example 5, and the liquid chromatography analysis conditions were as follows:

[0071] The mobile phase was water / ethanol, the flow rate was 1.0 mL / min, and the detection wavelength was 290 nm

[0072] 0 min-10 min water 100%

[0073] 10 min-20 min ethanol 0%→25%

[0074] 20min-25min ethanol 25%

[0075] 25min-30min ethanol 25%→30%

[0076] 30min-35min ethanol 30%

[0077] 35min-50min ethanol 30%→45%

[0078] 50min-55min ethanol 45%

[0079] 55min-65min ethanol 45%→90%

[0080] 65min-80min ethanol 90%

[0081] Figure 8 (b) The analytical column used was a C18 column (4.6 x 250 i.d. mm) and the liquid chromatography conditions were as follows:

[0082] The mobile phase was water / acetonitrile at a flow rate of 1.0 mL / min and the detection wavelength was 210 nm

[0083] 0min-20min acetonitrile / water: 20 / 80→60 / 40;

[0084] Example 11

[0085] Step (1) In a 2000 mL three-necked flask, 1080 mL of pure water, 6 g of polyvinyl alcohol and 6 g of sodium ducosate were added and stirred at 70°C for 20 minutes to completely dissolve the sodium ducosate and polyvinyl alcohol;

[0086] Step (2) In another beaker, 162 mL of xylene, 97 mL of divinyl benzene, 11 mL of γ-methacryloyloxypropyl trimethoxysilane and 0.7 g of AIBN were added and mixed well;

[0087] Step (3) The well-mixed organic phase in (2) was added to (1) and reacted at 70°C for 40 minutes, then the temperature was increased to 80°C and the reaction was continued for 8 hours. After the reaction was completed, the microspheres were washed with hot water, then with ethanol and finally dried to obtain the microspheres;

[0088] Step (4) 50 g of the microspheres prepared in (3) were dispersed in 800 mL of tetrahydrofuran and ultrasonicated for 20 minutes, then left to swell for 14 hours;

[0089] Step (5) 50 mL of ammonia water was added and stirred while ultrasonicated for 20 minutes, then left to stand for 30 hours. After the reaction was completed, the product was washed with water and ethanol and finally dried to obtain the target product;

[0090] The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer. 2 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer. 3 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer.

[0091] Example 12

[0092] In step (2) of Example 11, 97 mL of divinylbenzene and 11 mL of γ-methacryloyloxypropyltrimethoxysilane were replaced by 86 mL of divinylbenzene and 22 mL of γ-methacryloyloxypropyltrimethoxysilane, and the other steps were performed according to Example 11. The specific surface area was 610 m2 / g, the pore volume was 0.82 cm3 / g, and the average pore diameter was 5.29 nm, as determined by specific surface area analyzer. 2 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer. 3 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer.

[0093] Example 13

[0094] In step (2) of Example 11, 97 mL of divinylbenzene and 11 mL of γ-methacryloyloxypropyltrimethoxysilane were replaced by 76 mL of divinylbenzene and 32 mL of γ-methacryloyloxypropyltrimethoxysilane, and the other steps were performed according to Example 11. The specific surface area was 493 m2 / g, the pore volume was 0.58 cm3 / g, and the average pore diameter was 4.35 nm, as determined by specific surface area analyzer. 2 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer. 3 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer.

[0095] Example 14

[0096] 50 g of the microspheres prepared in Example 11 were dispersed in 275 mL of 1,2-dichloroethane and allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80°C for 8 h under nitrogen protection. After the reaction was completed, the product was washed with ethanol, then washed with dilute hydrochloric acid several times, washed with water until neutral, and finally dried to obtain the target product.

[0097] The specific surface area was 1175 m2 / g, the pore volume was 2.31 cm3 / g, and the average pore diameter was 8.34 nm, as determined by specific surface area analyzer. 2 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer. 3 The specific surface area was 678 m2 / g, the pore volume was 1.07 cm3 / g, and the average pore diameter was 6.48 nm, as determined by specific surface area analyzer.

[0098] Example 15

[0099] 50 g of the microspheres prepared in Example 12 were dispersed in 275 mL of 1,2-dichloroethane and allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80°C for 8 h under nitrogen protection. After the reaction was completed, the product was washed with ethanol, then washed with dilute hydrochloric acid several times, washed with water until neutral, and finally dried to obtain the target product.

[0100] The specific surface area analyzer was used for analysis, and the specific surface area was 1197 m 2 / g, the pore volume was 2.21 cm 3 / g, and the average pore size was 8.13 nm.

[0101] Example 16

[0102] 50 g of the microspheres prepared in Example 13 were dispersed in 275 mL of 1,2-dichloroethane, and were allowed to swell for 6 h. After swelling, 7.5 g of anhydrous ferric chloride was added, and the reaction was carried out at 80 DEG C for 8 h under nitrogen protection. After the reaction was completed, the product was washed with ethanol, and then was washed with dilute hydrochloric acid for several times. After being washed with water until neutral, the product was dried to obtain the target product.

[0103] The specific surface area analyzer was used for analysis, and the specific surface area was 1026 m 2 / g, the pore volume was 1.49 cm 3 / g, and the average pore size was 6.66 nm.

[0104] The method is simple and easy to scale up. The porous resin microspheres prepared by the method have good mechanical strength, contain a large number of reaction sites for modification, and can be modified according to different requirements, and are suitable for different separation systems.

Claims

1. A method for preparing silicone hybrid porous resin microspheres for liquid chromatography, characterized by: The preparation method is a suspension polymerization method, comprising the following steps: (1) adding a dispersing agent and a stabilizer into water at 50-70°C and stirring to dissolve, the mass fraction of the dispersing agent and the stabilizer is 0.5%-2%; the dispersing agent is selected from one or more than one of the following components: sodium docusate, gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium dodecyl sulfate, hydroxyethyl cellulose, hydroxypropyl cellulose, and sodium dodecyl benzene sulfonate; the stabilizer is selected from one or more than one of the following components: sodium docusate, gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium dodecyl sulfate, hydroxyethyl cellulose, hydroxypropyl cellulose, and sodium dodecyl benzene sulfonate; (2) taking a certain amount of xylene, divinylbenzene, γ-methacryloyloxypropyl trimethoxysilane and azobisisobutyronitrile and mixing them uniformly; the volume ratio of divinylbenzene and γ-methacryloyloxypropyl trimethoxysilane is 7:3-9:1, the amount of xylene is 1.5-3 times the sum of the volumes of divinylbenzene and γ-methacryloyloxypropyl trimethoxysilane, the amount of azobisisobutyronitrile is 0.5%-1.5% of the total mass of the comonomers, and the total mass of the comonomers is the sum of the masses of divinylbenzene monomers and γ-methacryloyloxypropyl trimethoxysilane monomers; (3) adding the organic phase mixed uniformly in step (2) into the reactor in step (1), wherein the volume ratio of the total volume of the organic phase to the volume of water is 1:3-1:5, reacting for 10-50 minutes, then continuing to heat to 70-80°C and continuing to react for 8-12 hours, and finally washing the microspheres with hot water and ethanol respectively; (4) adding the microspheres obtained in step (3) into tetrahydrofuran, ultrasonically swelling for 1-30 minutes, and then continuing to swell for 10-14 hours; the ratio of the microspheres to tetrahydrofuran is 1:10 g / mL-1:15 g / mL; (5) adding ammonia water into the reaction bottle in step (4), stirring thoroughly, standing, and finally washing the microspheres with water and ethanol; After step (5), a post-crosslinking method is further included, which comprises the following steps: dispersing the microspheres in 1,2-dichloroethane, swelling for 6-10 hours, adding anhydrous ferric chloride, heating to 70-90°C, reacting for 7-9 hours, washing with ethanol after the reaction is completed, washing with dilute hydrochloric acid, washing with water until neutral, and drying to obtain the target product, i.e. silicone hybrid porous resin microspheres for liquid chromatography.

2. The method of claim 1, wherein the method is characterized by: In step (3), the organic phase mixed uniformly in step (2) is added into the reactor in step (1) and reacted for 30-50 minutes.

3. The method of claim 1, wherein the method is characterized by: In step (5), the stirring is ultrasonic stirring, and the ultrasonic stirring is performed for 15-30 minutes; the standing time in step (5) is 18-36 hours.

4. The method of claim 1, wherein the method is characterized by: In step (5), the volume ratio of ammonia water to tetrahydrofuran is 1:15-1:

20.

5. The microspheres prepared by the method of claim 1, wherein the microspheres are characterized by: The organic-silicon hybrid porous resin microspheres obtained after the crosslinking treatment have a specific surface area of 1000-1200 m 2 / g, a pore volume of 1.2-1.8 cm 3 / g, and an average pore diameter of 5-8 nm; the microspheres can withstand a pressure of at least 3500 psi.

6. The microspheres prepared according to the method of claim 5, characterized in that: The particle size of the silicone hybrid porous resin microspheres obtained after the crosslinking treatment is 30-40 μm.

7. Use of the microspheres in any one of claims 5-6 in the separation of rebaudioside A by liquid chromatography.

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