Polyaniline nanotube and preparation method and application thereof

Abstract

The application discloses polyaniline nanotubes and a preparation method and application thereof, and the preparation method comprises the following steps: dissolving ammonium persulfate in a hydrochloric acid solution to obtain a solution A by ultrasonic treatment; mixing aniline and the hydrochloric acid solution to obtain a solution B by ultrasonic treatment; adding the solution A and the solution B into a microfluidic device respectively to carry out reaction, and centrifuging, washing and vacuum drying the reaction product to obtain a product polyaniline nanotube; the microfluidic technology is used, and the experimental operation is simplified; by changing the feeding ratio of aniline and ammonium persulfate, the reaction time and the reaction temperature, the polyaniline can be continuously and controllably prepared quickly and simply, and the application provides a potential scheme for the continuous and controllable synthesis of other materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer material preparation, in particular to a kind of polyaniline nanotube and its preparation method and application. BACKGROUND

[0002] With the discovery of conductive polymer in 1960, conductive polymer has attracted more and more attention in the fields of optics, electronics, energy and electroluminescence. Traditional view believes that organic polymers are insulators without conductive properties, but with the rapid development of polymer materials field in the 20th century, the discovery of conductive polymer materials breaks people's understanding of polymers.

[0003] Among existing conductive polymers, polyaniline can be synthesized by chemical and electrochemical methods in different organic solvents, even in aqueous medium, and has low monomer cost, adjustable performance and good stability, so it is considered as one of the most promising conductive polymers.

[0004] However, the main problem of all conductive polymers including polyaniline is that the conductivity of conductive polymers is lower than that of metals, and the solubility in all available solvents is poor; however, the solubility of polyaniline can be improved by doping suitable dopants or modifying monomers. Therefore, by selecting suitable dopants and suitable doping level, and controlling its structure during synthesis, there is enough space to change the conductivity and processability of polyaniline.

[0005] Traditional synthesis methods of polyaniline include electrochemical method, photochemical method, interfacial polymerization method and emulsion polymerization method, etc. For example, patent document No. CN114989425A discloses a method for preparing polyaniline by photochemistry; patent document No. CN113754882A discloses a method for synthesizing polyaniline compounds by using nitrogen as nitrogen source, lithium powder as reducing agent and zero-valent palladium as catalyst.

[0006] However, the existing preparation method has problems of long time consumption and low conductivity of the obtained compound. Therefore, it is of great practical significance to prepare a polyaniline with strong conductivity, simple operation process and continuous controllability for the application of conductive polymer afterwards. SUMMARY

[0007] In view of the shortcomings of the prior art, the purpose of the present application is to provide a kind of polyaniline nanotube and its preparation method and application, which has simple preparation process, continuous controllable preparation process, excellent conductivity of the prepared polyaniline nanotube, universality and very broad application prospect.

[0008] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0009] In a first aspect, the present application provides a preparation method of polyaniline nanotubes, comprising the following steps:

[0010] S1, adding ammonium persulfate into a hydrochloric acid solution, ultrasonic dispersion to obtain solution A;

[0011] S2, adding aniline into a hydrochloric acid solution, ultrasonic dispersion to obtain solution B;

[0012] S3, adding solution A and solution B into a microfluidic device respectively for reaction, after the reaction is completed, centrifuging, washing and vacuum drying the reaction product to obtain polyaniline nanotubes.

[0013] Preferably, the molar ratio of aniline and ammonium persulfate is 1:0.5-2.5.

[0014] Further preferably, the molar ratio of aniline and ammonium persulfate is 1:1.

[0015] Preferably, in step S3, the flow rates of solution A and solution B are the same.

[0016] Preferably, in step S3, the reaction temperature is-5-25℃.

[0017] Further preferably, the reaction temperature is 0℃.

[0018] Preferably, in step S3, the reaction time is 8-24h.

[0019] Preferably, in step S3, the vacuum drying temperature is 45-60℃, and the vacuum drying time is 12-24h.

[0020] In a second aspect, the present application provides polyaniline nanotubes prepared by the above preparation method.

[0021] In a third aspect, the present application also provides the application of the above polyaniline nanotubes in conductive materials.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] (1) The present application uses microfluidic technology, simplifies the experimental operation, the process is continuous and controllable, the reaction is fast and time-saving, and has universality; due to the characteristics of fast heat transfer, high mass transfer efficiency and small size of the microfluidic reactor, the mixing rate of aniline monomer, ammonium persulfate and hydrochloric acid solution in the microfluidic reactor is extremely fast, compared with traditional experiments, the reaction rate is obviously improved; at the same time, due to the rapid conduction and dissipation of the reaction heat by the microfluidic reactor, the "explosion polymerization" phenomenon caused by too high temperature is avoided to a certain extent, the side reaction is reduced, and the yield and purity of the product are improved.

[0024] (2) The microfluidic technology is used in the application, compared with traditional methods such as the emulsion polymerization method and the electrodeposition method, polyaniline can be continuously and stably synthesized, the operation is simple, the production efficiency is improved, meanwhile, the polyaniline nanotube obtained has excellent conductive performance, the conductivity can reach 14.29 S / cm, can be used as high-quality conductive filler, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A schematic diagram of the microfluidic reaction device used in the application is shown in the figure.

[0026] Figure 2 The XRD pattern of the polyaniline nanotube prepared in Example 1 of the application is shown in the figure.

[0027] Figure 3 The infrared spectrum of the polyaniline nanotube prepared in Example 1 of the application is shown in the figure.

[0028] Figure 4 The TEM pattern of the polyaniline nanotube prepared in Example 1 of the application is shown in the figure. DETAILED DESCRIPTION

[0029] The application will be further described in detail through specific preferred embodiments, but the application is not limited to the following embodiments.

[0030] It should be noted that, unless otherwise specified, the chemical reagents involved in the application are purchased through commercial channels.

[0031] The application provides a preparation method of polyaniline nanotube, comprising the following steps:

[0032] S1, ammonium persulfate is added to a hydrochloric acid solution, ultrasonic dispersion is carried out, and solution A is obtained.

[0033] In this step, the mass-volume ratio of ammonium persulfate and the hydrochloric acid solution is 1-10 g: 25 mL.

[0034] The concentration of the hydrochloric acid solution is 0.5-2 mol / L, for example, 0.5 mol / L, 1 mol / L, 1.5 mol / L or 2 mol / L can be selected.

[0035] The ultrasonic dispersion time is 5-10 min, for example, 5 min, 6 min, 7 min, 8 min, 9 min or 10 min can be selected.

[0036] S2, aniline is added to the hydrochloric acid solution, ultrasonic dispersion is carried out, and solution B is obtained.

[0037] In this step, the volume, concentration of the hydrochloric acid solution used are the same as in step S1; the molar ratio of aniline to ammonium persulfate is 1:0.5-2.5, and in some embodiments of the application, for example, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5 can be selected, but not limited to the listed values, and other values not listed within the value range are also applicable.

[0038] The ultrasonic dispersion time is 5-10 min, for example, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min can be selected, but not limited to the listed values, and other values not listed within the value range are also applicable.

[0039] S3, solution A and solution B are added to the microfluidic device for reaction, and after the reaction is completed, the reaction product is centrifuged, washed, and vacuum dried to obtain polyaniline nanotubes.

[0040] In this step, the microfluidic device as shown in Figure 1 The first raw material bottle (1), the second raw material bottle (2), the hastelloy pump (3), the stainless steel pump (4), the ice water bath device (5), and the product collection bottle (6) are connected in series through the heat preservation pipeline.

[0041] In this step, the flow rates of solution A and solution B are the same, and are set to 5-20 mL / min, further preferably 10-15 mL / min, and more preferably 10 mL / min.

[0042] In this step, the reaction temperature is -5-25℃, further preferably 0-10℃, and more preferably 0℃.

[0043] The reaction time is 8-24 h, further preferably 12-16 h, and more preferably 12 h.

[0044] In this step, the vacuum drying temperature is 45-60℃, for example, 45℃, 50℃, 55℃, 60℃ can be selected; the vacuum drying time is 12-24 h, for example, 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, 24 h can be selected; but not limited to the listed values, and other values not listed within the value range are also applicable.

[0045] The application will be further described in the following with specific examples.

[0046] Example 1

[0047] A preparation method of polyaniline nanotubes comprises the following steps:

[0048] 2.852g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution B; the microfluidic reaction device was cooled to 0℃ by using a hastelloy pump, a stainless steel pump and an ice water bath device, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 18h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a 60℃ vacuum drying oven for 24h to obtain polyaniline nanotubes.

[0049] The aspect ratio of the polyaniline nanotubes prepared in this example is 20, and the conductivity is 14.29S / cm.

[0050] Example 2

[0051] A preparation method of polyaniline nanotubes comprises the following steps:

[0052] 2.567g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution B; the microfluidic reaction device was cooled to 0℃ by using a hastelloy pump, a stainless steel pump and an ice water bath device, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 12h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a 60℃ vacuum drying oven for 24h to obtain polyaniline nanotubes.

[0053] The aspect ratio of the polyaniline nanotubes prepared in this example is 16, and the conductivity is 5.26S / cm.

[0054] Example 3

[0055] A preparation method of polyaniline nanotubes comprises the following steps:

[0056] 3.137g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, and ultrasonic treatment was performed for 5min to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, and ultrasonic treatment was performed for 5min to obtain solution B; the Hastelloy pump, the stainless steel pump and the ice water bath device of the microfluidic reaction device were adjusted to 25℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the Hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, and the microfluidic device was started to react for 12h; after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a vacuum drying oven at 60℃ for 24h to obtain polyaniline nanotubes.

[0057] The aspect ratio of the polyaniline nanotubes prepared in this example was 25, and the conductivity was 0.5S / cm.

[0058] Example 4

[0059] A method for preparing polyaniline nanotubes, comprising the following steps:

[0060] 3.137g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, and ultrasonic treatment was performed for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, and ultrasonic treatment was performed for 10min and cooled to 0℃ to obtain solution B; the Hastelloy pump, the stainless steel pump and the ice water bath device of the microfluidic reaction device were cooled to 0℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the Hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, and the microfluidic device was started to react for 12h; after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a vacuum drying oven at 60℃ for 24h to obtain polyaniline nanotubes.

[0061] The aspect ratio of the polyaniline nanotubes prepared in this example was 12, and the conductivity was 3.33S / cm.

[0062] Example 5

[0063] A method for preparing polyaniline nanotubes, comprising the following steps:

[0064] 7.131g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 10min and cooled to 0℃ to obtain solution B; the Hastelloy pump, stainless steel pump and ice water bath device of the microfluidic reaction device were cooled to 0℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the Hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 12h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a 45℃ vacuum drying oven for 24h to obtain polyaniline nanotubes.

[0065] The aspect ratio of the polyaniline nanotubes prepared in this example was 16, and the conductivity was 0.053S / cm.

[0066] Example 6

[0067] A method for preparing polyaniline nanotubes, comprising the following steps:

[0068] 7.131g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 10min and cooled to 0℃ to obtain solution B; the Hastelloy pump, stainless steel pump and ice water bath device of the microfluidic reaction device were cooled to 0℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the Hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 8h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, and dried in a 45℃ vacuum drying oven for 24h to obtain polyaniline nanotubes.

[0069] The aspect ratio of the polyaniline nanotubes prepared in this example was 10, and the conductivity was 0.0196S / cm.

[0070] Example 7

[0071] A method for preparing polyaniline nanotubes, comprising the following steps:

[0072] 5.705g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 10min and cooled to 0℃ to obtain solution B; the microfluidic reaction device of the hastelloy pump, stainless steel pump, ice water bath device was cooled to 0℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 8h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, dried in a vacuum drying oven at 60℃ for 12h to obtain polyaniline nanotubes.

[0073] The length-diameter ratio of the polyaniline nanotubes prepared in this example is 16, and the conductivity is 0.074S / cm.

[0074] Example 8

[0075] A method for preparing polyaniline nanotubes, comprising the following steps:

[0076] 5.705g of ammonium persulfate was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 5min and cooled to 0℃ to obtain solution A; 1.15ml of aniline was dissolved in 25mL of 1mol / L hydrochloric acid solution, ultrasonic for 10min and cooled to 0℃ to obtain solution B; the microfluidic reaction device of the hastelloy pump, stainless steel pump, ice water bath device was cooled to 0℃, then solution A was added to the first raw material bottle, solution B was added to the second raw material bottle, the flow rate of the hastelloy pump was set to 10ml / min, the flow rate of the stainless steel pump was set to 10ml / min, the microfluidic device was started to react for 8h, after the reaction was completed, the reaction product was centrifuged, washed with acetone and water alternately until the filtrate was clear and colorless, dried in a vacuum drying oven at 45℃ for 24h to obtain polyaniline nanotubes.

[0077] The length-diameter ratio of the polyaniline nanotubes prepared in this example is 16, and the conductivity is 0.073S / cm.

[0078] Finally, it should be noted that the above examples do not limit the present application in any form. For those skilled in the art, some modifications and improvements can be made on the basis of the present application. Therefore, any modification or improvement made without departing from the spirit of the present application shall fall within the scope of the present application.

Claims

1. A method for preparing polyaniline nanotubes, characterized by, The method comprises the following steps: S1, adding ammonium persulfate into a hydrochloric acid solution, ultrasonic dispersion, to obtain solution A; S2, adding aniline into a hydrochloric acid solution, ultrasonic dispersion, to obtain solution B; S3, adding solution A and solution B into a microfluidic device respectively for reaction, after the reaction is completed, centrifuging, washing and vacuum drying the reaction product, to obtain polyaniline nanotubes; The molar ratio of aniline and ammonium persulfate is 1:

1. In step S3, the reaction temperature is 0℃, and the reaction time is 18h.

2. The production method according to claim 1, characterized by, In step S3, the flow rates of solution A and solution B are the same.

3. The preparation method according to claim 1, characterized in that, In step S3, the temperature of vacuum drying is 45-60℃, and the time of vacuum drying is 12-24h.

4. The polyaniline nanotubes prepared by the preparation method in any one of claims 1-3.

5. The application of the polyaniline nanotubes in claim 4 in conductive materials.

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