Polymer for separating chiral single-walled carbon nanotubes and preparation method and application thereof

Abstract

The application discloses a polymer for separating chiral single-wall carbon nanotubes and a preparation method and application thereof. The polymer has the structure shown in the following formula: wherein n is selected from 5 to 60. The preparation method comprises the following steps: under a protective atmosphere, coupling reaction is caused to occur to a mixed reaction system containing 2,7-di(4,4,5,5-tetramethyl-1,3-dioxo-2-borane) 9,9-dioctyl fluorene, 2,6-dibromo-4-chloropyridine, Pd(PPh3)4 catalyst, Aliquiate 336, inorganic alkali and a first solvent, so as to prepare the polymer for separating chiral single-wall carbon nanotubes. The application synthesizes a new polymer for separating chiral single-wall carbon nanotubes, the polymer can be used for sorting (9,8) type single-wall carbon nanotubes, and the sorted (9,8) type single-wall carbon nanotubes have high purity and stability.

Description

Technical Field

[0001] This invention belongs to the field of nanotube technology, specifically relating to a polymer for separating chiral single-walled carbon nanotubes, its preparation method, and its application. Background Technology

[0002] One-dimensional carbon nanotubes (CNTs) have unique chemical, mechanical, thermal, electronic, and optical properties, making them highly valuable in both basic research and industry. Applications include high-strength nanocomposites, field-effect transistors (FETs), sensors, photodetectors, organic photovoltaics (OPVs), flexible devices, touchscreens, microelectronic interconnects, and other devices. Carbon nanotubes can be viewed as hollow cylinders formed by rolling up one or more layers of graphene. Based on the number of graphene sheets required to form a cylindrical shape, carbon nanotubes can be classified into single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (BHCNTs), and multi-walled carbon nanotubes (MWCNTs). Compared to MWCNTs, SWCNTs, based on their chirality index, allow for the determination of specific structures and variable electronic properties, thus holding immense potential for designing and developing nanodevices and nanochips for computing.

[0003] Currently, the main methods for separating single-chiral SWCNTs include pre-synthesis and post-purification techniques. Post-purification techniques primarily achieve chiral sorting through surfactant adsorption, π-π stacking of aromatic small molecules, and DNA or polymer entanglement. Compared to using surfactants or DNA to sort SWCNTs in aqueous phase, polymer extraction is widely used due to its simplicity (one-step separation).

[0004] Currently, the separation of (9,8)SWCNTs mainly involves pre-synthesis and post-synthesis separation methods. However, it has been reported that the purity of pre-synthesized (9,8)SWCNTs is low and does not meet current requirements. Subsequently, post-synthesis separation methods were adopted, using an aqueous two-phase method to further purify the synthesized (9,8)SWCNTs. However, the method of separating chiral SWCNTs in an aqueous phase has complex process requirements, and the SWCNTs separated in the aqueous system are mainly in the small diameter range (<1.05 nm). With the progress of thin-film transistor research, the demand for chiral SWCNTs with larger diameter ranges is becoming increasingly strong. Furthermore, in organic systems, given the diverse range of chiral SWCNTs, there is a strong demand for more conjugated polymers for separating chiral SWCNTs, especially those in the large diameter range. Summary of the Invention

[0005] The main objective of this invention is to provide a polymer for separating chiral single-walled carbon nanotubes, its preparation method, and its application, in order to overcome the shortcomings of the prior art.

[0006] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0007] This invention provides a polymer (denoted as C1-PFP) for separating chiral single-walled carbon nanotubes, which has a structure as shown in formula (I):

[0008]

[0009] Where n is selected from 5 to 60, and R is C6 to C6. 10 Alkyl groups.

[0010] This invention also provides a method for preparing the aforementioned polymer for separating chiral single-walled carbon nanotubes, comprising:

[0011] Under a protective atmosphere, a coupling reaction is carried out in a mixed reaction system comprising 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 2,6-dibromo-4-chloropyridine, a catalyst, a phase transfer catalyst, an inorganic base, and a first solvent to obtain the polymer for separating chiral single-walled carbon nanotubes.

[0012] The present invention also provides the use of the aforementioned polymer for separating chiral single-walled carbon nanotubes in separating (9,8) type single-walled carbon nanotubes (denoted as (9,8)SWCNTs).

[0013] This invention also provides a method for separating (9,8) type single-walled carbon nanotubes, comprising:

[0014] The aforementioned polymer for separating chiral single-walled carbon nanotubes is provided;

[0015] The polymer and single-walled carbon nanotube raw material are uniformly dispersed in a second solvent to form a dispersion solution;

[0016] Furthermore, the dispersion solution is separated into a solid phase and a liquid phase enriched with (9,8) type single-walled carbon nanotubes, thereby achieving the separation of (9,8) type single-walled carbon nanotubes.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] (1) The present invention designs and synthesizes a new polymer (denoted as C1-PFP) for separating chiral single-walled carbon nanotubes, which can be used to sort (9,8) type single-walled carbon nanotubes.

[0019] (2) The (9,8)SWCNTs sorted by C1-PFP have high purity and the prepared (9,8)SWCNTs solution has high stability. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the reaction for preparing polymer C1-PFP for separating chiral single-walled carbon nanotubes in a typical embodiment of the present invention;

[0022] Figure 2 This is the UV-Vis-NIR absorption spectrum of the supernatant obtained by centrifugation in Example 1 of the present invention;

[0023] Figure 3 This is a two-dimensional fluorescence spectrum of the supernatant obtained by centrifugation in Example 1 of the present invention;

[0024] Figure 4 This is a purity diagram of the (9,8) type single-walled carbon nanotubes in the supernatant obtained by centrifugation in Example 1 of the present invention. Detailed Implementation

[0025] In view of the deficiencies of the prior art, the inventors of this case, through long-term research and extensive practice, have proposed the technical solution of this invention. The technical solution of this invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] One aspect of this invention provides a polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes, having a structure as shown in formula (I):

[0027]

[0028] Where n is selected from 5 to 60, and R is C6 to C6. 10 Alkyl groups.

[0029] As a preferred embodiment, the polymer has a structure as shown in formula (II):

[0030]

[0031] Wherein, n is selected from 5 to 60. Another aspect of the present invention also provides a method for preparing the aforementioned polymer for separating chiral single-walled carbon nanotubes, comprising:

[0032] Under a protective atmosphere, a coupling reaction is carried out in a mixed reaction system comprising 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 2,6-dibromo-4-chloropyridine, a catalyst, a phase transfer catalyst, an inorganic base, and a first solvent to obtain the polymer for separating chiral single-walled carbon nanotubes.

[0033] In some more specific implementation schemes, the preparation method specifically includes:

[0034] Under a protective atmosphere, 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 2,6-dibromo-4-chloropyridine, a catalyst, a phase transfer catalyst, and a first solvent are mixed and heated until the 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene and 2,6-dibromo-4-chloropyridine dissolve, and then an inorganic base is added to form the mixed reaction system.

[0035] Furthermore, the mixed reaction system is reacted at 80–85°C for 1–7 days to obtain the polymer used for separating chiral single-walled carbon nanotubes.

[0036] In some more specific embodiments, the catalyst includes, but is not limited to, Pd(PPh3)4 and / or Pd(PPh3)2Cl2.

[0037] Furthermore, the phase transfer catalyst includes, but is not limited to, trioctylmethylammonium chloride (Aliquiate 336).

[0038] Furthermore, the inorganic base includes, but is not limited to, Na2CO3 and / or K2CO3.

[0039] Furthermore, the first solvent includes any one or a combination of two or more of toluene, tetrahydrofuran, and dimethylformamide, and is not limited thereto.

[0040] Furthermore, the molar ratio of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene to 2,6-dibromo-4-chloropyridine is 0.25–1:1–3.

[0041] Furthermore, the mass ratio of the catalyst to 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene is 1 to 10:100.

[0042] Furthermore, the protective atmosphere includes, but is not limited to, a nitrogen and / or argon atmosphere.

[0043] In some more specific implementations, the preparation method further includes: after the coupling reaction is completed, the obtained mixture is subjected to sedimentation, filtration, washing, drying and purification treatment.

[0044] Furthermore, the sedimentation treatment includes: mixing the obtained mixture with methanol for sedimentation treatment.

[0045] Furthermore, the washing process includes: dissolving the filtered product in CCl3, followed by water washing, rotary evaporation, sedimentation, and filtration.

[0046] Furthermore, the refining process includes: extracting the dried product using Soxhlet extraction.

[0047] Furthermore, the purification process includes: extracting the dried product sequentially with cyclohexane, acetone, and chloroform using Soxhlet extraction.

[0048] In some more specific embodiments, the method for preparing the polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes specifically includes (the reaction of the polymer as follows) Figure 1 As shown):

[0049] Under nitrogen atmosphere, two monomers (2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene and 2,6-dibromo-4-chloropyridine), 3% Pd(PPh3)4 catalyst, and 1 drop of Aliquiate 336 were added to a 25 ml Schlenk flask. 4 ml of toluene was added, and the mixture was heated to 80°C and stirred vigorously until both monomers were completely dissolved. Then, 1 ml of 2 mol / ml K2CO3 aqueous solution was added, and the reaction was maintained at 80–85°C for 3 days. The polymer was precipitated in 200 ml of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain a crude polymer product. Finally, the crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was dried under vacuum to obtain the polymer used for separating chiral single-walled carbon nanotubes. The CCl3 extract was used as the final product for subsequent experiments.

[0050] Another aspect of the present invention also provides the use of the aforementioned polymer for separating chiral single-walled carbon nanotubes in separating (9,8) type single-walled carbon nanotubes.

[0051] Another aspect of the present invention provides a method for separating (9,8) type single-walled carbon nanotubes, comprising:

[0052] The aforementioned polymer for separating chiral single-walled carbon nanotubes is provided;

[0053] The polymer and single-walled carbon nanotube raw material are uniformly dispersed in a second solvent to form a dispersion solution;

[0054] Furthermore, the dispersion solution is separated into a solid phase and a liquid phase enriched with (9,8) type single-walled carbon nanotubes, thereby achieving the separation of (9,8) type single-walled carbon nanotubes.

[0055] In some more specific implementations, the method specifically includes: using at least one of the following methods—ultrasound, oscillation, stirring, and grinding—to uniformly mix the polymer and the single-walled carbon nanotube raw material in a second solvent to form the dispersion solution.

[0056] Furthermore, the ultrasonic power of the ultrasonic treatment is 100-800W, and the ultrasonic time is 20-120min.

[0057] Furthermore, the ultrasonic power of the ultrasonic treatment is 400-600W, and the ultrasonic time is 30-60 minutes.

[0058] In some more specific implementations, the method specifically includes: centrifuging the dispersion solution at a speed of 10,000 g to 1,000,000 g for 20 min to 120 min, thereby separating the dispersion solution into a solid phase and a liquid phase enriched with (9,8) type single-walled carbon nanotubes.

[0059] Furthermore, the centrifugation speed is 20,000 to 50,000 g, and the time is 30 to 60 minutes.

[0060] In some more specific implementations, the method specifically includes: dissolving the polymer in a second solvent to form a polymer solution by means of ultrasound at a temperature of 10°C, and then adding single-walled carbon nanotube raw material and dispersing it by ultrasound to form the dispersion solution.

[0061] Furthermore, single-walled carbon nanotubes are ultrasonically dispersed in a polymer solution using an ultrasonic cell disruptor to form the dispersion solution, wherein the ultrasonic amplitude of the ultrasonic cell disruptor is 10% to 30%.

[0062] In some more specific embodiments, the method further includes: filtering the liquid phase of the enriched (9,8) type single-walled carbon nanotubes with a filter membrane with a pore size of 0.1 °Cm to obtain (9,8) type single-walled carbon nanotubes.

[0063] Furthermore, the diameter of the (9,8) type single-walled carbon nanotube is 1.17±0.01nm.

[0064] In some more specific embodiments, the ratio of the polymer, single-walled carbon nanotube raw material to the second solvent is 5-50 mg: 10-100 mg: 10-100 ml.

[0065] Furthermore, the ratio of the polymer, single-walled carbon nanotube raw material to the second solvent is 10-20 mg: 20-40 mg: 20-40 ml.

[0066] Furthermore, the second solvent includes, but is not limited to, toluene and / or xylene.

[0067] In some more specific embodiments, the method for separating (9,8) type single-walled carbon nanotubes specifically includes:

[0068] Weigh out a certain proportion of the aforementioned polymer and mix it with an organic solvent. Sonicate in a water bath to completely dissolve the polymer. Then add single-walled carbon nanotube raw material and sonicate it under an ultrasonic cell disruptor. Control the sonication time to ensure uniform mixing of carbon nanotubes and polymer. Set the ultrasonic amplitude to 30% and the water bath temperature to 10°C. After sonication, transfer the solution to a centrifuge tube for centrifugation within a short time. Set the temperature to 10°C and collect the supernatant in the tube. The supernatant can be further filtered using a 0.1μm needle filter. Collect the carbon nanotube precipitate in the centrifuge tube, and it can be reused after drying.

[0069] The technical solution of the present invention will be further described in detail below with reference to several preferred embodiments and accompanying drawings. This embodiment is implemented on the premise of the technical solution of the invention, and provides detailed implementation methods and specific operation processes. However, the protection scope of the present invention is not limited to the following embodiments.

[0070] Unless otherwise specified, the experimental materials used in the examples below can be purchased from conventional biochemical reagent companies.

[0071] Example 1

[0072] (1) Under nitrogen atmosphere, 1.106 mmol (710 mg) of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 1.106 mmol (300 mg) of 2,6-dibromo-4-chloropyridine, 3% Pd(PPh3)4 catalyst, and 1 drop of Aliquiate 336 were added to a 25 ml Schlenk flask. 4 ml of toluene was added, and the mixture was heated to 80 °C and stirred vigorously until both monomers were completely dissolved. 1 ml of 2 mol / ml K2CO3 aqueous solution was added, and the reaction was maintained at 83 °C for 3 days. The resulting polymer was precipitated in 200 ml of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain the crude polymer product. The crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was vacuum dried to obtain a polymer (denoted as C1-PFP) for separating chiral single-walled carbon nanotubes. The NMR characterization data of the prepared C1-PFP are as follows: 1 H NMR (400MHz, Chloroform-d) δ8.28-8.23 (d, J=8.1Hz, 2H), 8.18-8.14 (s, 2H), 7.96-7.91 (d, J=8.0Hz, 2H), 7.81-7.79 (s, 2H), 2.24-2.13 (s, 4H), 1.28-1.24 (d, J=6.0Hz, 4H), 1.16-1.06 (s, 20H), 0.79-0.77 (s, 6H); 13 CNMR (101MHz, CDCl3) δ 14.10, 22.65, 24.91, 29.33, 30.17, 31.87, 40.56, 55.57, 77.06, 118.65, 120.54, 121.52, 126.43, 128.49, 133.68, 137.73, 142.21, 145.32, 152.09, 158.64; Molecular weight: Mn = 13365, Mw = 28281, PDI = 2.12.

[0073] (2) Weigh 20 mg Cl-PFP polymer and 40 mg Hipco single-walled carbon nanotubes into a beaker, and then add 40 ml toluene to prepare a mixed solution; sonicate at 600 W for 30 min, then centrifuge at 50000 g for 30 min, and take the supernatant to obtain the liquid phase of enriched (9,8) type single-walled carbon nanotubes.

[0074] Using near-infrared-visible-ultraviolet absorption spectroscopy (UV-Vis-NIR) (see...) Figure 2 ), two-dimensional fluorescence spectrum (see) Figure 3 Testing of the liquid phase revealed that the separated supernatant mainly contained (9,8) single-walled carbon nanotubes. Fitting the near-infrared-visible-ultraviolet absorption spectra of the separated liquid phase enriched with (9,8) single-walled carbon nanotubes showed that the purity of the (9,8) single-walled carbon nanotubes was 82.54% (e.g., ...). Figure 4 (As shown). After Cl-PFP separation, no single-walled carbon nanotubes were found to settle at the bottom after one month.

[0075] Example 2

[0076] (1) Under nitrogen atmosphere, 1.106 mmol (710 mg) of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 1.106 mmol (300 mg) of 2,6-dibromo-4-chloropyridine, 3% Pd(PPh3)2Cl2 catalyst, and 1 drop of Aliquiate 336 were added to a 25 ml Schlenk flask. 4 ml of toluene was added, and the mixture was heated to 80 °C and stirred vigorously until both monomers were completely dissolved. 1 ml of 2 mol / ml Na2CO3 aqueous solution was added, and the reaction was maintained at 80 °C for 7 days. The resulting polymer was precipitated in 200 ml of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain the crude polymer product. The crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was vacuum dried to obtain a polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes. The NMR characterization of the prepared polymer is as follows: 1 H NMR (400MHz, Chloroform-d) δ8.28-8.23 (d, J=8.1Hz, 2H), 8.18-8.14 (s, 2H), 7.96-7.91 (d, J=8.0Hz, 2H), 7.81-7.79 (s, 2H), 2.24-2.13 (s, 4H), 1.28-1.24 (d, J=6.0Hz, 4H), 1.16-1.06 (s, 20H), 0.79-0.77 (s, 6H); 13CNMR (101 MHz, CDCl3) δ 14.10, 22.65, 24.91, 29.33, 30.17, 31.87, 40.56, 55.57, 77.06, 118.65, 120.54, 121.52, 126.43, 128.49, 133.68, 137.73, 142.21, 145.32, 152.09, 158.64; Molecular weight: Mn = 13365, Mw = 28281, PDI = 2.12.

[0077] (2) Weigh 10 mg of C1-PFP polymer and 20 mg of Hipco single-walled carbon nanotubes into a beaker, and then add 20 ml of xylene to prepare a mixed solution; sonicate at 400 W for 60 min, then centrifuge at 20000 g for 60 min, and take the supernatant to obtain the liquid phase of enriched (9,8) type single-walled carbon nanotubes.

[0078] Example 3

[0079] (1) Under nitrogen atmosphere, 1.106 mmol (710 mg) of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 1.106 mmol (300 mg) of 2,6-dibromo-4-chloropyridine, 3% Pd(PPh3)4 catalyst, and 1 drop of Aliquiate 336 were added to a 25 ml Schlenk flask. 4 ml of toluene was added, and the mixture was heated to 80 °C and stirred vigorously until both monomers were completely dissolved. 1 ml of 2 mol / ml K2CO3 aqueous solution was added, and the reaction was maintained at 85 °C for 1 day. The resulting polymer was precipitated in 200 ml of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain the crude polymer product. The crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was vacuum dried to obtain a polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes. The NMR characterization of the prepared polymer is as follows: 1H NMR (400MHz, Chloroform-d) δ 8.28-8.23 (d, J = 8.1Hz, 2H), 8.18-8.14 (s, 2H), 7.96-7.91 (d, J = 8.0Hz, 2H), 7.81-7.79 (s, 2H), 2.24-2.13 (s, 4H), 1.28-1.24 (d, J = 6.0Hz, 4H), 1.16-1.06 (s, 20H), 0.79-0.77 (s, 6H). 13CNMR (101MHz, CDCl3) δ 14.10, 22.65, 24.91, 29.33, 30.17, 31.87, 40.56, 55.57, 77.06, 118.65, 120.54, 121.52, 126.43, 128.49, 133.68, 137.73, 142.21, 145.32, 152.09, 158.64; Molecular weight: Mn = 13365, Mw = 28281, PDI = 2.12.

[0080] (2) Weigh 5mg Cl-PFP polymer and 10mg Hipco single-walled carbon nanotubes into a beaker, then add 10ml toluene to prepare a mixed solution; sonicate at 100W power for 2h, then centrifuge at 10000g for 2h, and take the supernatant to obtain the liquid phase of enriched (9,8) type single-walled carbon nanotubes.

[0081] Example 4

[0082] (1) Under nitrogen atmosphere, 1.106 mmol (710 mg) of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 1.106 mmol (300 mg) of 2,6-dibromo-4-chloropyridine, 3% Pd(PPh3)4 catalyst, and 1 drop of Aliquiate 336 were added to a 25 ml Schlenk flask. 4 ml of tetrahydrofuran was added, and the mixture was heated to 80 °C and stirred vigorously until both monomers were completely dissolved. 1 ml of 2 mol / ml K2CO3 aqueous solution was added, and the reaction was maintained at 81 °C for 3 days. The resulting polymer was precipitated in 200 ml of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain the crude polymer product. The crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was vacuum dried to obtain a polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes. The NMR characterization of the prepared polymer is as follows: 1 H NMR (400MHz, Chloroform-d) δ8.28-8.23 (d, J=8.1Hz, 2H), 8.18-8.14 (s, 2H), 7.96-7.91 (d, J=8.0Hz, 2H), 7.81-7.79 (s, 2H), 2.24-2.13 (s, 4H), 1.28-1.24 (d, J=6.0Hz, 4H), 1.16-1.06 (s, 20H), 0.79-0.77 (s, 6H); 13CNMR (101 MHz, CDCl3) δ 14.10, 22.65, 24.91, 29.33, 30.17, 31.87, 40.56, 55.57, 77.06, 118.65, 120.54, 121.52, 126.43, 128.49, 133.68, 137.73, 142.21, 145.32, 152.09, 158.64; Molecular weight: Mn = 13365, Mw = 28281, PDI = 2.12.

[0083] (2) Weigh 50mg Cl-PFP polymer and 100mg Hipco single-walled carbon nanotubes into a beaker, and then add 100ml toluene to prepare a mixed solution; sonicate at 800W for 20min, then centrifuge at 100000g for 20min, take the supernatant, and then filter the liquid phase with a filter membrane with a pore size of 0.1μm to obtain (9,8) type single-walled carbon nanotubes.

[0084] Example 5

[0085] Under nitrogen atmosphere, 1.106 mmol (710 mg) of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 1.106 mmol (300 mg) of 2,6-dibromo-4-chloropyridine, 3% Pd(PPh3)4 catalyst, and 1 drop of Aliquiate 336 were added to a 25 mL Schlenk flask. 4 mL of dimethylformamide was added, and the mixture was heated to 80 °C and stirred vigorously until both monomers were completely dissolved. 1 mL of 2 mol / mL K2CO3 aqueous solution was added, and the reaction was maintained at 82 °C for 3 days. The resulting polymer was precipitated in 200 mL of ice-cold methanol and filtered. The product was dissolved in CCl3, washed three times with water, and the solvent was removed using a rotary evaporator. The resulting polymer was precipitated in ice-cold methanol, filtered, and dried under vacuum to obtain the crude polymer product. The crude product was extracted sequentially with cyclohexane, acetone, and chloroform using the Soxhlet extraction method until the fluorescence at the siphon tube completely disappeared. The solvent was removed using a rotary evaporator, and the product was vacuum dried to obtain a polymer (denoted as Cl-PFP) for separating chiral single-walled carbon nanotubes. The NMR characterization of the prepared polymer is as follows: 1H NMR (400MHz, Chloroform-d) δ 8.28-8.23 (d, J = 8.1Hz, 2H), 8.18-8.14 (s, 2H), 7.96-7.91 (d, J = 8.0Hz, 2H), 7.81-7.79 (s, 2H), 2.24-2.13 (s, 4H), 1.28-1.24 (d, J = 6.0Hz, 4H), 1.16-1.06 (s, 20H), 0.79-0.77 (s, 6H).13 CNMR (101 MHz, CDCl3) δ 14.10, 22.65, 24.91, 29.33, 30.17, 31.87, 40.56, 55.57, 77.06, 118.65, 120.54, 121.52, 126.43, 128.49, 133.68, 137.73, 142.21, 145.32, 152.09, 158.64; Molecular weight: Mn = 13365, Mw = 28281, PDI = 2.12.

[0086] (2) Weigh 15mg Cl-PFP polymer and 30mg Hipco single-walled carbon nanotubes into a beaker, and then add 30ml xylene to prepare a mixed solution; sonicate at 500W for 40min, then centrifuge at 30000g for 45min, take the supernatant, and then filter the liquid phase with a filter membrane with a pore size of 0.5μm to obtain (9,8) type single-walled carbon nanotubes.

[0087] Furthermore, there are currently no suitable polymers for separating (9,8) single-walled carbon nanotubes.

[0088] The inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0089] It should be understood that the technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made to the technical solutions of the present invention without departing from the spirit and scope of the claims are within the scope of protection of the present invention.

Claims

1. A polymer for separating chiral single-walled carbon nanotubes, characterized in that: It has the structure shown in equation (I): （I） Where n is selected from 5 to 60, and R is C6 to C6. 10 Alkyl groups.

2. The polymer according to claim 1, characterized in that, The polymer has a structure as shown in formula (II): （Ⅱ） Where n is selected from 5 to 60.

3. The method for preparing the polymer for separating chiral single-walled carbon nanotubes according to claim 1 or 2, characterized in that... include: Under a protective atmosphere, a coupling reaction is carried out in a mixed reaction system comprising 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 2,6-dibromo-4-chloropyridine, a catalyst, a phase transfer catalyst, an inorganic base, and a first solvent to obtain the polymer used for separating chiral single-walled carbon nanotubes.

4. The preparation method according to claim 3, characterized in that... Specifically, it includes: Under a protective atmosphere, 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene, 2,6-dibromo-4-chloropyridine, a catalyst, a phase transfer catalyst, and a first solvent are mixed and heated until the 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylyl)-9,9-dioctylfluorene and 2,6-dibromo-4-chloropyridine dissolve, and then an inorganic base is added to form the mixed reaction system. Furthermore, the mixed reaction system is reacted at 80~85°C for 1~7 days to obtain the polymer used for separating chiral single-walled carbon nanotubes; And / or, the catalyst comprises Pd(PPh3)4 and / or Pd(PPh3)2Cl2; And / or, the phase transfer catalyst comprises trioctylmethylammonium chloride; And / or, the inorganic base includes Na2CO3 and / or K2CO3; And / or, the first solvent includes any one or a combination of two or more of toluene, tetrahydrofuran, and dimethylformamide; And / or, the molar ratio of 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylalkyl)-9,9-dioctylfluorene to 2,6-dibromo-4-chloropyridine is 0.25~1:1~3; And / or, the mass ratio of the catalyst to 2,7-bis(4,4,5,5-tetramethyl-1,3-dioxo-2-borylalkyl)-9,9-dioctylfluorene is 1 to 10:100; And / or, the protective atmosphere includes a nitrogen and / or argon atmosphere; And / or, the preparation method further includes: after the coupling reaction is completed, subjecting the obtained mixture to sedimentation, filtration, washing, drying, and purification treatment; wherein, the sedimentation treatment includes: mixing the obtained mixture with ice-cold methanol for sedimentation treatment; the washing treatment includes: dissolving the filtered product in HCl3, followed by water washing, rotary evaporation, sedimentation, and filtration treatment; the purification treatment includes: extracting the dried product using Soxhlet extraction.

5. Use of the polymer for separating chiral single-walled carbon nanotubes as described in claim 1 or 2 in the separation of (9,8) type single-walled carbon nanotubes.

6. A method for separating (9,8) type single-walled carbon nanotubes, characterized in that... include: Provide the polymer for separating chiral single-walled carbon nanotubes as described in claim 1 or 2; The polymer and single-walled carbon nanotube raw material are uniformly dispersed in a second solvent to form a dispersion solution; Furthermore, the dispersion solution is separated into a solid phase and a liquid phase enriched with (9,8) type single-walled carbon nanotubes, thereby achieving the separation of (9,8) type single-walled carbon nanotubes.

7. The method according to claim 6, characterized in that... Specifically, it includes: At least one of the following methods—ultrasound, oscillation, stirring, and grinding—is used to uniformly mix the polymer and single-walled carbon nanotube raw material in a second solvent to form the dispersion solution. And / or, the method specifically includes: centrifuging the dispersion solution with a relative centrifugal force of 10,000 g to 1,000,000 g for 20 min to 120 min, thereby separating the dispersion solution into a solid phase and a liquid phase enriched with (9,8) type single-walled carbon nanotubes.

8. The method according to claim 6, characterized in that... Specifically, the process involves dissolving the polymer in a second solvent using ultrasound at a temperature of 10°C to form a polymer solution, followed by adding single-walled carbon nanotube raw materials and dispersing them using ultrasound to form the dispersion solution.

9. The method according to claim 6, characterized in that... It also includes: using a filter membrane to filter the liquid phase of the enriched (9,8) type single-walled carbon nanotubes, thereby obtaining (9,8) type single-walled carbon nanotubes; And / or, the diameter of the (9,8) type single-walled carbon nanotube is 1.17±0.01nm.

10. The method according to claim 6, characterized in that: The ratio of the polymer, single-walled carbon nanotube raw material to the second solvent is 5~50mg:10~100mg:10~100ml; And / or, the second solvent includes toluene and / or xylene.

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