Polyester thermally degraded tubular carbon and method for producing the same

Abstract

The present application provides a kind of polyester thermal degradation tubular carbon and its preparation method, the polyester thermal degradation tubular carbon is obtained by heat treatment from raw material including iron ion containing compound and polyester, iron ion containing compound is used as catalyst in the present application, heat treatment is preferably carried out high temperature heat treatment by unidirectional heating, the combined action of unidirectional high temperature heat transfer and the above-mentioned catalyst is beneficial to form tubular residue, the resistivity of the polyester thermal degradation tubular carbon described in the present application is more than 5 times of pure PET thermal decomposition residue, the electrical conductivity is poor, the specific surface area is higher than the specific surface area of PET thermal decomposition residue, which is beneficial to the adsorption of gas, and can be applied to heat-insulating material, and the tubular carbon has excellent mechanical properties, and can be used as anti-dripping agent, and has good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of carbon materials, in particular to a polyester thermal degradation tubular carbon and a preparation method thereof. BACKGROUND

[0002] Metal-organic framework materials (MOFs) are a kind of coordination polymers developed rapidly in recent ten years, have a three-dimensional pore structure, generally take metal ions as connecting points, and have organic ligands supporting to form a spatial 3D extension, and are a new type of important porous material in addition to zeolites and carbon nanotubes, and have wide applications in catalysis, energy storage and separation.

[0003] The MOFs material has important roles in the fields of gas storage, small molecule separation and catalysis due to its special structural properties and changes in its internal structure.

[0004] With the gradual understanding of the connection between organic and inorganic parts, the potential application value of the MOFs material is gradually reflected, and the MOFs has been transformed from a novel substance into a functional material, which is not only because it has the properties possessed by conventional substances (molecular sieve, adsorption, energy storage), but more importantly, its applications are deeply involved in many other fields, such as solid chemistry and physical chemistry due to its compressibility, life science due to its ability to store and carry drugs, and nanoscience due to its ability to provide single-layer dispersed nanoparticles.

[0005] Polyesters are polymers obtained by polycondensation of polyols and polyacids, are a kind of engineering plastics with excellent performance and wide application, and include polyester resins and polyester elastomers. With the rapid development of China's economy, the apparent consumption of polyester chips in China increases rapidly, the polyester production capacity in China develops rapidly, but a large amount of waste is generated due to the large use of polyesters, and the treatment of waste accounts for only a very small part of the waste each year. Therefore, how to effectively treat a large amount of polyester waste becomes a problem to be solved. SUMMARY

[0006] Based on the above technical background, the present inventors made great efforts, and found that the degradation carbon obtained by one-way high-temperature thermal degradation after reaction of a waste polyester with an iron ion-containing compound as a catalyst has a tubular structure, the tubular carbon has a large specific surface area and resistivity, can be applied to heat-resistant insulating materials, has excellent mechanical properties and high modulus, can be used as a molten droplet-resistant agent, effectively reduces the molten droplets generated in a fire, has a good application prospect, and provides a new idea for the treatment and effective use of waste polyesters, so the present application is completed.

[0007] The first aspect of the present application provides a polyester thermal degradation tubular carbon, which is prepared from raw materials including an iron ion-containing compound and a polyester by heat treatment.

[0008] The iron ion-containing compound is selected from one or more of ferric nitrate, trivalent iron MOFs, ferric chloride, ferric sulfate and ferric acetate.

[0009] The second aspect of the present application provides a preparation method of the polyester thermally degraded tubular carbon, and the preparation method comprises the following steps:

[0010] Step 1, blending the iron ion-containing compound with the polyester to obtain a composite material;

[0011] Step 2, thermally degrading the composite material at high temperature to obtain the tubular carbon.

[0012] The third aspect of the present application provides an application of the polyester thermally degraded tubular carbon according to the first aspect of the present application or prepared by the preparation method according to the second aspect of the present application, and the polyester thermally degraded tubular carbon is characterized in that it can be applied in heat-resistant insulation materials and anti-dripping agents. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 An infrared spectrum of the tubular carbon prepared in Example 1 is shown;

[0014] Figure 2 An XRD spectrum of the tubular carbon prepared in Example 1 is shown;

[0015] Figure 3 A scanning electron microscope photo of the trivalent iron MOF prepared in Example 1 is shown;

[0016] Figure 4 A scanning electron microscope photo of the products prepared in Example 1 and Comparative Example 1 is shown;

[0017] Figure 5 A TG spectrum of the trivalent iron MOF prepared in Example 1 is shown;

[0018] Figure 6 A Raman spectrum of the tubular carbon prepared in Example 1 is shown;

[0019] Figure 7 A scanning electron microscope photo of the products prepared in Examples 1-3 and Comparative Examples 3-4 is shown;

[0020] Figure 8 A scanning electron microscope photo of the products prepared in Example 1 and Example 4 is shown;

[0021] Figure 9 A stress-strain curve of the products prepared in Comparative Example 1 and Example 1 is shown. DETAILED DESCRIPTION

[0022] The present application will be described in detail below, and the features and advantages of the present application will become more apparent with these descriptions.

[0023] The first aspect of the present application provides a polyester thermally degraded tubular carbon, which is prepared by heat treatment of raw materials comprising an iron ion-containing compound and a polyester.

[0024] The polyester is selected from one or more of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polycarbonate, preferably selected from one or more of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and more preferably is polyethylene terephthalate.

[0025] The tubular carbon has excellent performance, and provides a new idea and method for the reuse and effective treatment of waste polyesters.

[0026] The iron ion-containing compound mainly acts as a catalyst, and is selected from one or more of ferric nitrate, trivalent iron MOFs, ferric chloride, ferric sulfate and ferric acetate, preferably selected from one or more of ferric nitrate and trivalent iron MOFs.

[0027] It has been found through experiments that the iron ion-containing compound can act as a catalyst to form tubular carbon with special morphology, and the above-mentioned iron-containing compound has high catalytic efficiency, and in particular, the tubular carbon obtained by using ferric nitrate and trivalent iron MOFs for catalysis is more dense and has more uniform morphology.

[0028] The trivalent iron MOFs are mainly prepared from an iron salt and terephthalic acid.

[0029] The iron salt is selected from one or more of ferric nitrate, ferric chloride, ferric sulfate, ferric acetate, ferric bromide and ferric iodide, preferably selected from one or more of ferric nitrate, ferric chloride, ferric sulfate and ferric acetate, and more preferably is one or both of ferric nitrate and ferric chloride.

[0030] The molar ratio of the iron salt to terephthalic acid is (0.5-3):1, preferably (0.7-2):1, and more preferably (0.8-1.5):1.

[0031] The heat treatment is preferably performed by unidirectional heating, and more preferably by high-temperature heat treatment using a cone calorimeter.

[0032] The cone calorimeter is a unidirectional high-temperature heat transfer, and the difference in heat transfer mode is the main reason affecting the formation of tubular residues. It has been found through experiments that unidirectional heating is conducive to the formation of tubular thermal degradation products, while multidirectional uniform heating, such as heating using a muffle furnace, easily leads to disordered structure of thermal decomposition residues, which is not conducive to the formation of tubular carbon.

[0033] The mass ratio of the polyester to the iron ion-containing compound is (10-700):1, preferably (30-600):1, and more preferably (50-500):1.

[0034] The present inventors have found that the amount of the iron ion-containing compound affects the morphology of the product, and when the amount is within the above range, it is more advantageous to form tubular carbon with a more uniform morphology.

[0035] In a preferred embodiment of the present application, the heat treatment temperature is 600-1000°C, preferably 650-900°C, and more preferably 700-800°C.

[0036] The heat treatment time is 1-20 min, preferably 2-15 min, and more preferably 3-10 min.

[0037] When the thermal degradation temperature and time of the tubular carbon are within the above range, the MIL-PET can rapidly undergo second-stage oxidative decomposition to provide a large amount of carbon dioxide and water, rapidly diluting oxygen so that the internal matrix has the opportunity to undergo anaerobic thermal degradation and gradually form residues with easier decomposition or gasification, which have a lower decomposition temperature and a slower decomposition rate, and can better protect the inner polymer matrix under high-temperature conditions. Under the action of oxygen in the air and unidirectional heat source, the thermal decomposition residues of the MIL-PET and the matrix gradually undergo thermal oxidative decomposition or sublimation in a small amount, and the more difficult-to-decompose part is retained and further deposited to form tubular structure thermal decomposition residues.

[0038] The trivalent iron MOFs prepared by the present application have absorption peaks of C=O group, benzene ring and Fe-O at 1664 cm -1 , 749 cm -1 and 538 cm -1 , respectively. At the same time, the tubular carbon has crystal faces of 100, 101, 002, 102, etc. in the XRD pattern, and the thermal decomposition temperature is greater than 300°C.

[0039] The resistivity of the tubular carbon prepared by the present application is 65000-85000 Ω·m, which is 5.2-5.5 times that of pure PET thermal decomposition residues, and the electrical performance is poor, which can be used for heat-resistant and insulating materials. In addition, the specific surface area of the tubular carbon is 420-500 m 2 / g, which is increased by 15% compared with that of the PET thermal decomposition residues.

[0040] The tubular carbon has excellent mechanical properties, and the modulus is 15-25 MPa, which can be used as a molten droplet-resistant agent.

[0041] The second aspect of the present application provides a preparation method of the tubular carbon prepared by the polyester thermal degradation according to the first aspect of the present application, which comprises the following steps:

[0042] Step 1, blending the iron ion-containing compound with the polyester to obtain a composite material;

[0043] Step 2, high-temperature thermal degradation of the composite material to obtain a tubular carbon.

[0044] The step is described and explained in detail as follows.

[0045] Step 1, blending the iron ion-containing compound with the polyester to obtain a composite material.

[0046] The iron ion-containing compound mainly acts as a catalyst, and the iron ion-containing compound is selected from one or more of ferric nitrate, trivalent iron MOFs, ferric chloride, ferric sulfate and ferric acetate, preferably one or both of ferric nitrate and trivalent iron MOFs.

[0047] The trivalent iron MOFs are mainly prepared by the reaction of an iron salt and terephthalic acid.

[0048] The iron salt is selected from one or more of ferric nitrate, ferric chloride, ferric sulfate, ferric acetate, ferric bromide and ferric iodide, preferably one or more of ferric nitrate, ferric chloride, ferric sulfate and ferric acetate, and more preferably one or both of ferric nitrate and ferric chloride.

[0049] The reaction is carried out in a solvent selected from one or more of dimethylformamide (DMF), ethanol, water and tetrahydrofuran, preferably one or both of dimethylformamide and ethanol.

[0050] The amount of solvent added is not particularly limited, as long as the iron salt and terephthalic acid can be completely dissolved.

[0051] The molar ratio of the iron salt to terephthalic acid is (0.5-3):1, preferably (0.7-2):1, and more preferably (0.8-1.5):1.

[0052] When the molar ratio of the iron salt to terephthalic acid is within the above range, the preparation of the MOF material is facilitated, the prepared MOF material has good thermal performance and catalytic efficiency, can be used in polymerization reactions, still has good catalytic activity at high temperatures, is conducive to the formation of tubular carbon, and the obtained tubular carbon has a more uniform morphology.

[0053] The iron salt and terephthalic acid are preferably stirred before the reaction to mix uniformly in the solvent, the stirring speed is 100-1000 rpm, preferably 200-500 rpm, and the stirring time is 10-60 min, preferably 20-45 min.

[0054] The reaction is preferably carried out in an autoclave, and the reaction temperature is 100-180℃, preferably 120-160℃, and more preferably 130-150℃.

[0055] When the reaction temperature is in the above range, the iron salt and terephthalic acid react sufficiently, and the terephthalic acid is not affected in chemical structure after the terephthalic acid reacts with the metal ion, and the iron ion can successfully coordinate with the oxygen element in the carbonyl group to form an iron-oxygen coordination bond.

[0056] The reaction time is 15-30h, preferably 18-28h, and more preferably 20-25h.

[0057] After the reaction, centrifugation, washing, and drying are performed. The centrifugation speed is 5000-15000rpm, and preferably 8000-12000rpm.

[0058] The centrifugation time is 5-20h, and preferably 7-15h.

[0059] The washing agent is preferably ethanol, and the washing is performed multiple times.

[0060] The drying is preferably vacuum drying, the drying temperature is 100-150℃, preferably 110-130℃, and the drying time is 5-20h, preferably 10-15h.

[0061] The polyester is selected from one or more of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polycarbonate, preferably selected from one or more of polyethylene terephthalate, polypropylene terephthalate, and polybutylene terephthalate, and more preferably polyethylene terephthalate.

[0062] The mass ratio of the polyester to the iron ion-containing compound is (10-700):1, preferably the mass ratio is (30-600):1, and more preferably the mass ratio is (50-500):1.

[0063] Before blending, the waste polyester is preferably crushed, washed, and dried, and the drying temperature is 60-90℃, and preferably 70-80℃.

[0064] The drying time is 15-30h, and preferably the drying time is 20-25h.

[0065] The blending temperature is 200-350℃, preferably 240-320℃, and more preferably 250-300℃.

[0066] The blending time is 1-20min, preferably 2-15min, and more preferably 2-10min.

[0067] It is found through experiments that at a too high blending temperature, the metal ion may accelerate the decomposition of the polymer, and the polyester becomes brittle. When the temperature is lower than 240℃, the polymer may not be sufficiently melted, and the blending effect is poor.

[0068] Step 2, high-temperature thermal degradation of the composite material to obtain tubular carbon.

[0069] In the present application, the high-temperature thermal degradation is preferably carried out by unidirectional heating. Unidirectional heating refers to heating on any one side of the material, and the material is unevenly heated in each direction, and the side of the heating is the highest in temperature. More preferably, a cone calorimeter is used to carry out high-temperature thermal degradation of the composite material MIL-PET.

[0070] It has been found through experiments that the product morphology obtained by uniform heating and unidirectional heating is not the same, and unidirectional heating is more conducive to the formation of tubular residues, while uniform heating, such as heating in a muffle furnace, results in a disordered product structure, which is not conducive to the formation of tubular thermal degradation carbon.

[0071] The thermal degradation temperature is 600-1000℃, preferably 650-900℃, and more preferably 700-800℃.

[0072] The thermal degradation time is 1-20min, preferably 2-15min, and more preferably 3-10min.

[0073] The present inventors have found that when the thermal degradation temperature is lower than 600℃, the residual carbon still maintains a relatively smooth structure, and as the temperature increases, the residual carbon gradually develops pores, but the overall structure still remains relatively smooth. As the thermal degradation temperature increases, the pores gradually increase, and the thermal degradation time is relatively short, and the tubular formation is insufficient, with mainly large blocks and fragmented residual carbon. As the thermal degradation time increases, especially when the thermal degradation time is 3-10min, the thermal degradation carbon is mainly in the form of tubular carbon.

[0074] After thermal degradation, vacuum drying is carried out at a drying temperature of 60-90℃, preferably 70-80℃, and the drying temperature is 5-20h, preferably 10-15h.

[0075] The third aspect of the present application provides an application of the tubular carbon based on MOFs polyester thermal degradation according to the first aspect of the present application or prepared by the preparation method according to the second aspect of the present application, which can be applied in heat-resistant insulation materials and anti-dripping agents.

[0076] The present application has the following beneficial effects:

[0077] (1) The tubular carbon based on MOFs polyester thermal degradation has a resistivity of more than 5 times that of pure PET thermal decomposition residues, and poor electrical conductivity, which can be used in heat-resistant insulation materials;

[0078] (2) The specific surface area of the tubular carbon based on MOFs polyester thermal degradation is increased by 15% compared to that of PET thermal decomposition residues, which is beneficial to gas adsorption;

[0079] (3) The tubular carbon based on MOFs polyester thermal degradation has excellent mechanical properties and greater strength, and can be used as a polymer anti-dripping agent;

[0080] (4) The preparation method of the tubular carbon is simple, no toxic and harmful gas is generated in the preparation process, is green and environmentally friendly, provides a new idea for effective utilization and treatment of waste polyester, and has good application prospect.

[0081] Examples

[0082] The application will be further described below through specific examples, which are only limited to illustrate the application, and are not used to limit the scope of the application.

[0083] Example 1

[0084] 1.66 g (1.0 mmol) of terephthalic acid (TPA) and 4.04 g (1.0 mmol) of iron nitrate nonahydrate (Fe(NO3)3·9H2O) were added to 100.0 ml of DMF, and after magnetic stirring at 400 rpm for 30 minutes at room temperature, the mixed solution was poured into a polytetrafluoroethylene liner of a stainless steel autoclave, heated in an oven at 140℃ for 24 hours, the product was centrifuged at 10000 rpm for 10h, washed with ethanol three times, and vacuum dried at 120℃ for 12h, and then naturally cooled to room temperature to obtain the trivalent iron MOFs.

[0085] The waste PET (mineral water beverage bottle) was crushed, washed, and dried at 80℃ for 24h, and then 700g of treated waste PET and 7g of trivalent iron MOFs were added and hot-pressed at 280℃ for 3 minutes to obtain a composite material.

[0086] According to ISO 5660-1, a conical test was carried out using a fire resistance test technology (FTT) standard cone calorimeter (FTTL, UK) under an external heat flow of 50kW / m 2 The sample size of the composite material was 100.0x100.0x3.0mm 3 The thermal degradation product was vacuum dried at 80℃ for 12h to obtain a tubular residual carbon.

[0087] The specific surface area of the tubular residual carbon was 457.40m 2 / g by BET test.

[0088] Example 2

[0089] The preparation of the polyester thermal degradation tubular carbon material was carried out in a similar manner to Example 1, except that the composite material was fully thermally degraded in a CONE test at 700℃ for 10 minutes.

[0090] Example 3

[0091] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the composite material was fully thermally degraded in the CONE test at 768°C for 3 minutes.

[0092] Example 4

[0093] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the preparation of the ferric MOFs was not carried out, and 700 g of treated waste PET and 7 g of ferric nitrate were added and hot-pressed at 280°C for 3 minutes.

[0094] Comparative Example

[0095] Comparative Example 1

[0096] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the ferric MOFs were not added.

[0097] The specific surface area of the tubular residual carbon was 397.74 m 2 / g by BET test.

[0098] Comparative Example 2

[0099] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the composite material was placed in a muffle furnace and thermally degraded at 768°C for 5 minutes.

[0100] Comparative Example 3

[0101] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the composite material was fully thermally degraded in the CONE test at 500°C for 10 minutes.

[0102] Comparative Example 4

[0103] The preparation of the polyester thermally degraded tubular carbon material was carried out in a similar manner as in Example 1, except that the composite material was fully thermally degraded in the CONE test at 600°C for 10 minutes.

[0104] Experimental Example

[0105] Experimental Example 1 Infrared Spectroscopy Test

[0106] The MOFs prepared in Example 1 were subjected to infrared spectroscopy test, and the test results are shown in Figure 1 .

[0107] As can be seen from Figure 1 , 1664 cm -1 , 749 cm -1and 538 cm -1 The absorption peaks of C=O group, benzene ring and Fe-O respectively indicate that the chemical structure of terephthalic acid is not affected after the terephthalic acid reacts with metal ions, and the iron ions successfully coordinate with the oxygen element in the carbonyl group to form iron-oxygen coordination bonds.

[0108] Experimental Example 2: XRD Test

[0109] The MOFs prepared in Example 1 were subjected to XRD test, and the test results are shown in Figure 2

[0110] Figure 2 The crystal faces of 100, 101, 002 and 102 in the XRD pattern indicate that the MOFs are successfully synthesized.

[0111] Experimental Example 3: Scanning Electron Microscope Test

[0112] The MOFs prepared in Example 1, the tubular carbon prepared in Example 1 and the product prepared in Comparative Example 1 were subjected to scanning electron microscope test, and the test results of the MOFs prepared in Example 1 are shown in Figure 3 , the test results of the tubular carbon prepared in Example 1 and the product prepared in Comparative Example 1 are shown in Figure 4 , and the test results of the products prepared in Examples 1-3 and Comparative Examples 3-4 are shown in Figure 7 . The test results of the tubular carbon prepared in Example 1 and Example 4 are shown in Figure 8

[0113] It can be seen from Figure 3 that the MOFs are successfully prepared.

[0114] Figure 4 In the above, the first row is the optical microscope photos, and the second row is the scanning electron microscope photos, Fig. a1, a2 are the photos of Comparative Example 1, Fig. b1, b2 are the photos of the tubular carbon prepared in Example 1, and c1, c2 are the photos of the flocculent substance. It can be seen from Fig. a1, a2 that the PET thermal decomposition residue is smooth and has obvious pore structure, in Fig. b1, b2, the tubular carbon prepared in Example 1 is relatively rough, and red particulate matter is deposited on the surface.

[0115] It can be seen from Figure 7 that when the thermal degradation temperature is 500℃ or 600℃, the surface of the carbon residue remains relatively smooth structure, and when the thermal degradation temperature is 700℃, the surface of the carbon residue gradually appears pores and begins to form tubular carbon. When the thermal degradation time is short, the tubular carbon is not sufficient, and mainly is large block and fragment-shaped carbon residue. When the thermal degradation time is 5min, the carbon residue is mainly tubular carbon.

[0116] Figure 8 ​In the images, b1 and b2 are scanning electron microscope (SEM) images of the tubular carbon prepared in Example 4, and c1 and c2 are SEM images of the tubular carbon prepared in Example 1. It can be seen that the tubular carbon prepared using ferric nitrate is relatively sparse, while the tubular carbon prepared using ferric MOFs is relatively dense, indicating that the catalytic efficiency of ferric MOFs is higher than that of ferric nitrate.

[0117] Experimental Example 4: TG Test

[0118] The MOFs prepared in Example 1 were subjected to TG testing, and the test results are as follows: Figure 5 As shown.

[0119] from Figure 5 As can be seen, the MOFs prepared by this invention have good thermal properties, with an initial thermal decomposition temperature greater than 300℃, and can be used in polymerization reactions.

[0120] Experimental Example 5: Raman Spectroscopy Test

[0121] Raman spectroscopy was performed on the tubular carbon prepared in Comparative Example 1 and Example 1. The test results are as follows: Figure 6 As shown.

[0122] from Figure 6 As can be seen, the D4 area ratio of the tubular carbon prepared in Example 1 increased significantly, while the I area ratio of the tubular carbon prepared in Example 1 also increased significantly. D / I G and I G / I all Also compared with the tubular carbon prepared in Comparative Example 1, I D / I G and I G / I all A higher value indicates that it is more prone to thermal oxide decomposition.

[0123] Experimental Example 6: Stress-Strain Test

[0124] Stress-strain tests were performed on the products obtained in Comparative Example 1 and Example 1. The test results are as follows: Figure 9 As shown.

[0125] Figure 9 In the study, the stress-strain curves of the two products exhibit a distinct trapezoidal shape, indicating that they possess a porous structure. The thermal decomposition residue undergoes brittle fracture during compression. By selecting some connection points for fitting, the slope, i.e., the compressive modulus, was obtained. It can be seen that the modulus gradually increases with increasing strain, reaching 15-25 MPa, which is much higher than the modulus of Comparative Example 1. The tubular thermal decomposition residue has a larger modulus due to surface strengthening, which is beneficial for reducing the molten entropy generated in fires and improving fire safety. It can be used as an anti-dripping agent.

[0126] Experiment Example 7 Resistivity Test

[0127] The corresponding powders prepared by milling Example 1 and Comparative Example 1 were tested for resistivity using the four-probe method. The test results are shown in Table 1.

[0128] Table 1

[0129]

[0130] As can be seen from Table 1, the resistivity test result of Comparative Example 1 is 11000-25000 Ω·m, and the resistivity of the Example is 65000-85000 Ω·m, indicating that after the formation of the tubular carbon, the resistivity is significantly improved, and the conductivity is significantly reduced.

[0131] The above detailed description of the application is made in conjunction with specific embodiments and exemplary examples, but these descriptions cannot be understood as limiting the application. Those skilled in the art understand that various equivalent substitutions, modifications or improvements can be made to the technical solutions and embodiments of the application without departing from the spirit and scope of the application, and these all fall within the scope of the application. The scope of protection of the application is subject to the appended claims.

Claims

1. A method for the production of a thermally degraded tubular carbon of a polyester, characterized in that, The polyester thermal degradation tubular carbon is prepared from raw materials including an iron ion-containing compound and a polyester by heat treatment, and the method comprises the following steps: Step 1, blending the iron ion-containing compound and the polyester to obtain a composite material; Step 2, high-temperature thermal degradation of the composite material to obtain a tubular carbon; In step 1, the iron ion-containing compound is a trivalent iron MOF, the polyester is selected from one or more of polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate; the blending temperature is 240-320 DEG C, and the blending time is 2-15 min; In step 2, the heat treatment is performed by unidirectional heating; the mass ratio of the polyester to the iron ion-containing compound is (10-700): 1, the heat treatment temperature is 650-900 DEG C, and the heat treatment time is 2-15 min.

2. The preparation method according to claim 1, characterized in that, The resistivity of the polyester thermally degraded tubular carbon is 65000-85000 Ω·m, the specific surface area is 420-500 m 2 / g, and the modulus is 15-25 Mpa.

3. The preparation method according to claim 1, characterized in that, in step 1, the trivalent iron MOF is mainly prepared from an iron salt and terephthalic acid, and the molar ratio of the iron salt to terephthalic acid is (0.5-3): 1; the reaction temperature is 100-180 DEG C, and the reaction time is 15-30 h.

4. The preparation method according to claim 1, characterized in that, In step 1, the polyester is polyethylene terephthalate; the blending temperature is 250-300 DEG C, and the blending time is 2-10 min.

5. The preparation method according to claim 1, characterized in that, In step 2, the thermal degradation temperature is 700-800 DEG C, and the thermal degradation time is 3-10 min.

6. The polyester thermal degradation tubular carbon prepared by the preparation method of any one of claims 1 to 5 is applied to heat-resistant insulation materials and anti-dripping agents.

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