Preparation method and application of Fe3O4 (at) PS-P (St-DMA) nano material

Abstract

The invention discloses a preparation method and application of a Fe3O4 (at) PS-P (St-DMA) nano material, and the preparation method comprises the following steps: S1, mixing Fe3O4 (at) PS-P (St-DMA) with methanol, and carrying out ultrasonic treatment to form a uniform dispersion liquid; s2, styrene, dimethylaminoethyl methacrylate and azodiisobutyronitrile are mixed according to the molar ratio of 1: 1: 1, then BCBD and the dispersion liquid formed in the S1 are added, nitrogen is introduced for sealing, and a mixed solution is obtained; s3, reacting the mixed solution obtained in the step S2 in an oil bath pan environment at 50-65 DEG C for 40-50 hours to obtain a reaction solution; and S4, centrifuging the reaction liquid to obtain solid particles, and drying the solid particles to obtain a polymerization product Fe3O4 (at) PS-P (St-DMA) nano material. The Fe3O4 (at) PS-P (St-DMA) has wormlike nanowires on the surface by combining the excellent performance of the Fe3O4 (at) PS magnetic nanomaterial and modifying with dimethylaminoethyl methacrylate, so that the specific surface area of the adsorbing material is increased, and the adsorbability of the material is better.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanomaterials, and particularly relates to a preparation method and application of Fe3O4@PS-P(St-DMA) nanomaterials. Background Art

[0002] Plasticizers, also known as plasticizers, are distributed between macromolecular chains. Their main function is to reduce the intermolecular force, lower the viscosity between polymers, and enhance flexibility. They are often used in industrial production to enhance the plasticity of resin molecules. Their addition amount in plastics exceeds 30%. Among many commercial plasticizers, phthalates are the most frequently used one. Currently, its total global consumption has far exceeded 8 million tons, and its market share in the total addition amount of all plasticizers can account for more than four-fifths. Phthalate compounds are basically colorless oily viscous liquids. They are easily soluble in oils but hardly soluble in water and are difficult to volatilize at room temperature and are prone to migration. Therefore, humans are almost exposed to them every day, and the PAEs pollution problem has gradually become a hot issue of concern.

[0003] When single Fe3O4 nanoparticles are loaded on carbon-based materials, their adsorption sites will be reduced, and irreversible aggregation is likely to occur, resulting in poor applicability to pH values. However, such metal oxides at the nanoscale have problems such as poor selectivity during the extraction process, and it is often necessary to select an appropriate coating layer to achieve the stability and antioxidant properties of the nanoparticles. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a preparation method and application of Fe3O4@PS-P(St-DMA) nanomaterials, and solve the above technical problems existing in the prior art.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A preparation method of Fe3O4@PS-P(St-DMA) nanomaterials includes the following steps:

[0007] S1. Mix Fe3O4@PS-BCBD with methanol and form a uniform dispersion after ultrasonic treatment;

[0008] S2. Mix styrene, dimethylaminoethyl methacrylate, and azobisisobutyronitrile in a molar ratio of 1:1:1, then add BCBD and the dispersion formed in S1, and seal it by introducing nitrogen to obtain a mixed solution;

[0009] S3. React the mixed solution obtained in S2 in an oil bath environment at 50 - 65 °C for 40 - 50 h to obtain a reaction solution;

[0010] S4. Centrifuge the reaction solution to obtain solid particles, and after drying, obtain the polymeric product Fe3O4@PS-P(St-DMA) nanomaterial.

[0011] Furthermore, the dosage of BCBD in S2 is 5 - 6 times that of styrene.

[0012] Furthermore, the sealing time of introducing nitrogen in S2 is 25 - 35 min.

[0013] Furthermore, the solid particles obtained in S4 are washed with formaldehyde and then dried to obtain the polymeric product Fe3O4@PS-P(St-DMA) nanomaterial.

[0014] An application of the Fe3O4@PS-P(St-DMA) nanomaterial as an adsorbent for plasticizers.

[0015] Furthermore, when the Fe3O4@PS-P(St-DMA) nanomaterial is used as an adsorbent for plasticizers, the ultrasonic treatment is 3 - 5 min and the ultrasonic time is 5 - 6 min.

[0016] Furthermore, the Fe3O4@PS-P(St-DMA) nanomaterial as an adsorbent for plasticizers has repeatability.

[0017] Advantages of the present invention:

[0018] 1. In the present application, by combining the excellent properties of the Fe3O4@PS magnetic nanomaterial and then modifying it with dimethylaminoethyl methacrylate, the obtained Fe3O4@PS-P(St-DMA) has worm-like nanowires on its surface, increasing the specific surface area of the adsorbent material and making the adsorption property of the material better.

[0019] 2. In the present application, the role of styrene is to increase the hydrophobicity of the material and play a role in adsorbing benzene-ring organic compounds; dimethylaminoethyl methacrylate enhances the hydrophilicity of the material, making the dispersion of the nanoparticles in the aqueous phase better. This gives the magnetic nanomaterial better development prospects and practicality in analytical detection.

[0020] 3. In the present application, using Fe3O4@PS-P(St-DMA) as the adsorbent material achieves the goals of rapidity, high precision, high extraction rate, low loss, and high reproducibility, providing a new analytical method for the detection of plasticizer pollutants. Description of the Drawings

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a schematic diagram of the preparation process of Fe3O4@PS-P(St-DMA) in the embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of the infrared spectrum analysis of Fe3O4@PS-P(St-DMA) in the embodiment of the present invention;

[0024] Figure 3 It is a transmission electron microscope image of Fe3O4@PS-P(St-DMA) in the embodiment of the present invention;

[0025] Figure 4 It is a schematic diagram of the influence of the dosage of the Fe3O4@PS-P(St-DMA) adsorbent in the embodiment of the present invention;

[0026] Figure 5 It is a schematic diagram of the influence of the Fe3O4@PS-P(St-DMA) adsorbent and the ultrasonic time in the embodiment of the present invention;

[0027] Figure 6 It is a schematic diagram of the influence of the dosage of the eluent on the extraction effect of Fe3O4@PS-P(St-DMA) in the embodiment of the present invention.

[0028] Figure 7 It is a schematic diagram of the influence of the Fe3O4@PS-P(St-DMA) adsorbent and the elution time in the embodiment of the present invention;

[0029] Figure 8 It is a schematic diagram of the reuse rate of the Fe3O4@PS-P(St-DMA) adsorbent in the embodiment of the present invention. Detailed implementation manners

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] Example 1:

[0032] The embodiment of the present invention provides a preparation method of Fe3O4@PS-P(St-DMA) nanomaterials, including the following steps:

[0033] The detailed preparation process of Fe3O4@PS-P(St-DMA) is as follows Figure 1 shown. Specifically, 0.2 g of Fe3O4@PS-BCBD and 30 ml of methanol are added to a 100-ml single-necked flask. After ultrasonic treatment for 30 min, a homogeneous dispersion is formed. Subsequently, styrene (St, 0.52 g, 5 mmol), dimethylaminoethyl methacrylate (DMA, 0.785 g, 5 mmol), AIBN (8 mg), and BCBD (40 mg) are added to the dispersion respectively. Then the dispersion flask is sealed and purged with nitrogen for 30 min. The reaction flask is transferred to an oil bath, and the reaction is carried out in an oil bath environment at 60 °C for 48 h. Then the reaction solution is centrifuged at high speed. After obtaining solid particles by the reaction, they are washed with methanol three times and dried in vacuum to obtain the product. Finally, weighing shows that the obtained polymerization product is 0.3 g. The role of styrene is to increase the hydrophobicity of the material and play a role in adsorbing benzene-ring organic compounds. The role of dimethylaminoethyl methacrylate is to increase the hydrophobicity of the material and improve the dispersion of particles in the aqueous phase.

[0034] Add a small amount of Fe3O4@PS-P(St-DMA) to a mortar and mix it with potassium bromide. After mixing the sample with potassium bromide until no particles can be seen with the naked eye, a thin plate can be pressed and subjected to infrared characterization (denoted by PS). As can be seen from the figure Figure 2 it can be seen that Fe3O4 is a common iron oxide, and the bending vibration peak of its Fe-O bond is in the range of 400-500 cm -1 interval. Therefore, the peak at 494.96 cm -1 here is the characteristic peak of Fe3O4. At the wave peak of 1159.24 cm -1 is the stretching vibration peak of the C=N bond. At the wave peak of 1400.53 cm -1 it can be judged that this is the deformation vibration of the O-H bond of the acid. And 1624.83 is the characteristic peak of C=O. In the band of 3000-4000 cm -1 in the range, at 3423.15 cm -1 the vibration peak of the C-H resonance aromatic group site can be seen. In addition, at 3238.71 cm -1 a weaker and more dissociative C-H resonance vibration peak can also be seen compared to the previous item. The above conclusions indicate that the -P(St-DMA) group has been successfully coated on Fe3O4@PS and can be successfully detected by infrared chromatography. The structure of the material can be roughly estimated through infrared chromatography.

[0035] As Figure 3As shown, it can be seen from the figure that when the scale is 100 nm, opaque black small balls can be clearly seen in the figure. Light gray small balls are connected to the outside of the black small balls. The light gray transparent small balls are arranged closely and irregularly to form worm-like nanowires, and the quantity and shape and length are different. Thus, it can be speculated from the structure that the dark black small ball in the middle is Fe3O4, and the worm-like dark gray small balls connected to the outside will modify the PS-P(St-DMA) group of Fe3O4, and form worm-like nanowires on the surface of Fe3O4, thereby increasing the specific surface area of Fe3O4@PS-P(St-DMA) and the target analyte, enhancing the adsorption of the magnetic material, and the particle size of the small balls is between 50 - 100 nm, indicating that this material belongs to the nanoscale level.

[0036] The specific magnetic solid-phase extraction process is as follows:

[0037] (1) Weigh the sample: Take a clean glass bottle and place it on the analytical balance to tare. After the balance is stable, weigh 10 mg of the sample Fe3O4@PS-P(St-DMA).

[0038] (2) Activation: Open the bottle cap, and use a pipette to suck 5 ml of pure water and 5 ml of methanol into the glass bottle respectively, gently shake and let it stand for activation for 2 min, and then ultrasonicate for 5 min.

[0039] (3) First magnetic separation: Place the glass bottle containing the magnetic material after ultrasonication beside the magnet, let it stand for adsorption, wait until the water sample becomes clear, and use a disposable Pasteur pipette to suck out the activation solution along the bottle wall.

[0040] (4) Add water standard sample: Use a pipette to transfer 20 ml of the water sample into the glass bottle, gently shake it to make the dispersant as evenly dispersed as possible, and let it stand for 2 min. Then ultrasonicate for 5 min. During ultrasonication, to make the magnetic material more evenly dispersed and better adsorb the target substance, the glass bottle containing the sample can be shaken appropriately while ultrasonicating.

[0041] (5) Second magnetic separation: Place the glass bottle of the sample after ultrasonication beside the magnet and let it stand. Wait until the sample solution becomes completely clear, and pour out the sample solution.

[0042] (6) Elution: After the sample solution in the bottle is removed, use a pipette to transfer 5 ml of acetone to elute the magnetic material in the glass bottle containing the sample. After elution, gently shake the bottle body to make the adsorption material on the bottle wall dissolve into the eluent as much as possible.

[0043] (7) Third magnetic separation: Place the eluted glass bottle beside the magnet and wait until the sample solution in the bottle becomes completely clear. Use a straw to suck out the sample solution along the bottle wall and place it in a glass tube.

[0044] (8) Nitrogen blowing and volume fixation: Blow the eluate with nitrogen until the volume is below 1 ml, and then fix the volume to 1 ml. Filter the eluate through a 0.22 μm organic phase filter head into a 1.5 ml standard injection vial and analyze it by gas chromatography - mass spectrometry.

[0045] Example 2:

[0046] For phthalic acid as a mixed standard substance, as Figure 4 shown, the effect of the dosage of Fe3O4@PS - P(St - DMA) adsorbent on its adsorption efficiency. The adsorption effects of 2 mg - 10 mg adsorbents (i.e., 2 mg, 4 mg, 6 mg, 8 mg, 10 mg respectively) on a mixed standard sample of 7 phthalate esters are as follows. In each group, from left to right are DMP (dimethyl phthalate), DEP (diethyl phthalate), DIBP (diisobutyl phthalate), DBP (dibutyl phthalate), BBP (butyl benzyl phthalate), DEHP (bis(2 - ethylhexyl) phthalate), DNOP (dioctyl phthalate). Among them, the adsorption effect gradually increases with the increase of the adsorbent dosage. Fe3O4@PS - P(St - DMA) has a good adsorption effect on phthalate ester compounds in the mixed sample under the condition of 8 mg. With the increase of the adsorbent dosage, the adsorption effect of Fe3O4@PS - P(St - DMA) under the condition of 10 mg is close to that of 8 mg. Therefore, in this experiment, the adsorbent dosage of 8 mg is selected as the optimal adsorbent dosage and applied to actual samples.

[0047] For the CAS numbers and MRM parameters of each component in the above - mentioned 7 - component phthalate mixed standard, as shown in Table 1.

[0048] Table 1

[0049]

[0050] Example 3:

[0051] As Figure 5As shown, it can clearly reflect the relationship between the ultrasonic time in the magnetic solid-phase extraction process and the adsorption efficiency of the Fe3O4@PS-P(St-DMA) material. From the figure, we can see that when the ultrasonic extraction time is in the range of 1 - 3 min, the adsorption efficiency of Fe3O4@PS-P(St-DMA) shows a gradually increasing trend, indicating that within this range, ultrasonic treatment is required during the magnetic solid-phase extraction process to improve the adsorption of the material. When the ultrasonic extraction time exceeds 3 min, the adsorption efficiency of Fe3O4@PS-P(St-DMA) will decrease slightly. With the increase of the ultrasonic extraction time, the adsorption efficiency of Fe3O4@PS-P(St-DMA) will also change, but the change is not significant after 4 min. It can be seen from the figure that when the ultrasonic extraction time reaches 3 min, the adsorption efficiency of Fe3O4@PS-P(St-DMA) is the highest. Although the adsorption efficiency in the range of 4 - 5 min is better than that at 1 - 2 min, it is still slightly worse than that at 3 min. Therefore, 3 min will be selected as the optimal ultrasonic time for this experiment. Among them: the order of the 7 phthalic acid esters is the same as that in Example 2 above.

[0052] Example 4:

[0053] As Figure 6 shown, it clearly shows the influence of the amount of eluent in the Fe3O4@PS-P(St-DMA) magnetic adsorption material on its adsorption performance. The amount of eluent has a slight increase in the range of 1 - 4 ml, but the amplitude is not large. When the amount of eluent is 4 ml, the adsorption force of Fe3O4@PS-P(St-DMA) is the best. When the amount of eluent is increased to 5 ml, the extraction rate is similar to that at 3 ml. Therefore, 4 ml of eluent is selected as the optimal extraction condition for the next experiment in this experiment. Among them: the order of the 7 phthalic acid esters is the same as that in Example 2 above.

[0054] Example 5:

[0055] As Figure 7 shown, it can be clearly seen from the figure the relationship between the elution time and the adsorption efficiency of the Fe3O4@PS-P(St-DMA) material. With the increase of time, the adsorption efficiency of the Fe3O4@PS-P(St-DMA) material shows a gradually increasing trend. When the elution time is 5 min, the adsorption efficiency of the Fe3O4@PS-P(St-DMA) material is the best. When the elution time is 5 min, the adsorption efficiency of the Fe3O4@PS-P(St-DMA) material is the best. Therefore, the elution time of 5 min is selected as the optimal elution time condition for this experiment.

[0056] Example 6:

[0057] AsFigure 8 As shown, after the weighed 8 mg of Fe3O4@PS-P(St-DMA) was reused 6 times, its extraction efficiency for 7 samples decreased slightly, but generally there was no significant change. This indicates that the research method is highly feasible and has high recyclability. At the same time, it also shows that Fe3O4@PS-P(St-DMA), as a new type of magnetic nanomaterial, has good application and development prospects in magnetic solid-phase extraction pretreatment technology and phthalate detection and analysis.

[0058] Example 7:

[0059] Take 20 mL each from three different beverages. After filtration, add 0 μg (without addition), a mixed standard solution of seven phthalates at 0.1 μg / mL, and a mixed standard solution of seven phthalates at 0.5 μg / mL respectively. At the same time, combine the optimized parameters with the experiment to verify the experimental results. In addition, the pollution situations of the three samples were analyzed. It can be seen from the experiment that although the spiked water samples used were different, the actual detection data did not change significantly due to the change of the spiked water samples. From this, the feasibility of this experimental method in actual operation can be verified, and the pollution situations of the three different beverage water samples can be analyzed. The specific situation is shown in Table 2 below:

[0060] Table 2

[0061]

[0062]

[0063]

[0064] As shown in Table 2 above, the adsorption rates of the three water samples at spiked amounts of 0.1 μg / mL and 0.5 μg / mL. Experiments have proved that when the spiked amount is 0.1 μg / mL, the spiked recovery rates of the three water samples are between 14.2% and 99.6%.

[0065] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A preparation method of Fe3O4@PS-P(St-DMA) nanomaterials, characterized in that, It includes the following steps: S1. Mix Fe3O4@PS-BCBD with methanol, and form a uniform dispersion after ultrasonic treatment; S2. Mix styrene, dimethylaminoethyl methacrylate, and azodiisobutyronitrile in a molar ratio of 1:1:1, then add BCBD and the dispersion formed in S1, and introduce nitrogen for sealing to obtain a mixed solution; S3. React the mixed solution obtained in S2 in an oil bath environment at 50-65 °C for 40-50 h to obtain a reaction solution; S4. Centrifuge the reaction solution to obtain solid particles, and dry them to obtain the polymer product Fe3O4@PS-P(St-DMA) nanomaterial.

2. The preparation method of the Fe3O4@PS-P(St-DMA) nanomaterial according to claim 1, characterized in that, The dosage of BCBD in S2 is 5-6 times that of styrene.

3. The preparation method of the Fe3O4@PS-P(St-DMA) nanomaterial according to claim 1, wherein, The sealing time of introducing nitrogen in S2 is 25-35 min.

4. The preparation method of the Fe3O4@PS-P(St-DMA) nanomaterial according to claim 1, characterized in that, The solid particles obtained in S4 are washed with formaldehyde and then dried to obtain the polymer product Fe3O4@PS-P(St-DMA) nanomaterial.

5. Application of a Fe3O4@PS-P(St-DMA) nanomaterial, characterized in that, The Fe3O4@PS-P(St-DMA) nanomaterial according to any one of claims u1-4, as an adsorbent for plasticizers.

6. Use of the Fe3O4@PS-P(St-DMA) nanomaterial according to claim 5, characterized in that, When the Fe3O4@PS-P(St-DMA) nanomaterial is used as an adsorbent for plasticizers, the ultrasonic treatment is for 3-5 min, and the ultrasonic time is 5-6 min.

7. Use of the Fe3O4@PS-P(St-DMA) nanomaterial according to claim 5, characterized in that, The Fe3O4@PS-P(St-DMA) nanomaterial is used as an adsorbent for plasticizers.

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