Method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene material

Abstract

The invention discloses a method for oxidative degradation recovery and function / high-performance reconstruction of a waste polyethylene material, which comprises the following steps of: oxidizing the waste polyethylene material, and degrading the obtained oxidized polyethylene by using an ester-based degradation reagent to obtain a telechelic degradation product of the waste polyethylene, then, hydroxyl in the obtained telechelic degradation product of the waste polyethylene is modified into an aldehyde group through an esterification reaction, and the modified degradation product is further combined with a functional monomer to obtain a novel material with functions and high performance. According to the method disclosed by the invention, ester groups are introduced while the waste polyethylene is oxidized and degraded, a telechelic degradation product is obtained through degradation of the ester groups, and high-performance / functional dynamic cross-linked network reconstruction is carried out on the telechelic degradation product through subsequent modification, so that the mechanical property of the reconstructed material is greatly enhanced, and the mechanical property of the reconstructed material is greatly improved. The reconstructed material is applied to the fields of flame retardance, static electricity resistance, dyeing and the like, and the use value of the reconstructed material is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of waste polymer material recycling and functional high-performance reconstruction, and specifically relates to a method for oxidative degradation recycling of waste polyethylene materials, and functional and high-performance reconstruction of oxidative degradation products. Background Art

[0002] Polyethylene is one of the five major general-purpose plastics. Due to its excellent overall performance, it is widely used in a wide range of fields, including disposable packaging, agriculture, electronics, and electrical appliances. Furthermore, due to its low production cost, it is the most used and most discarded general-purpose plastic. According to the China Materials Recycling Association, the total amount of polyethylene waste in China reached 13.2 million tons in 2022. However, due to its stable chemical structure and difficulty in degradation and recycling, polyethylene's disposal leads to serious ecological and environmental pollution, resource waste, and carbon emissions, making it a major source of white pollution.

[0003] Currently, chemical recycling of polyethylene primarily involves pyrolysis or hydrogenolysis to produce fuel oil or hydrocarbon chemical feedstocks. However, oxidative degradation is gaining increasing attention from both industry and academia due to its relatively mild conditions and the potential for higher-value utilization by imparting reactive functional groups to the degradation products. Oxidative degradation of polyethylene typically involves the use of oxidants such as oxygen and hydrogen peroxide to degrade the polyethylene material into products with carboxyl functional groups. These dibasic acid products can then be repolymerized to produce novel materials. For example, CN117304015A discloses a method for the photocatalytic oxidative degradation of polyolefins. This method utilizes a photothermal catalyst, leveraging the synergistic effects of sunlight (1.0-10 AM) and heat to oxidize polyolefins into short-chain aliphatic dicarboxylic acids (C3-C16) under relatively mild conditions (50-180°C, 1-20 bar O2). For example, CN117229564A discloses a method for recovering high-value-added polyolefin plastics by low-temperature catalytic oxidation cracking. This method uses microporous ZSM 5 molecular sieve as a catalyst to oxidatively degrade polyolefins in an aqueous phase to obtain liquid long-chain dibasic acids.

[0004] Although polyethylene can be degraded into polymerizable products through oxidative degradation, the poor controllability of the oxidative degradation process and the complex structure of the degradation products, resulting in not only a wide molecular weight distribution but also a mixture of monoacids and diacids, have resulted in few reports on the direct reconstitution of these degradation products into high-performance materials. Only Coats et al. (J. Am. Chem. Soc. 2022, 144, 23280−23285) reported the degradation of polyethylene into molecular weight-adjustable telechelic macromolecules terminated with hydroxyethyl esters via a dehydrogenation-olefin metathesis-hydrogenation process. These macromolecules were then subjected to linear polymerization. However, due to the presence of some monofunctional structures in these degradation products, the molecular weight of the resulting materials obtained by direct linear polymerization was low (Mn ≤ 18 kDa), and their mechanical properties did not match those of the original polyethylene. Therefore, the development of simple, efficient, molecular weight-adjustable polyethylene degradation methods and effective reconstitution methods is urgently needed to enhance the value of these degradation products. Summary of the Invention

[0005] The purpose of the present invention is to address the problems existing in the prior art and provide a method for oxidative degradation and recycling of waste polyethylene materials, as well as for reconstructing the functions and high performance of the oxidative degradation products.

[0006] The present invention provides a method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials, and the process steps and conditions of the method are as follows: (1) Dissolve the waste polyethylene material in solvent I, then add an oxidant, or add a catalyst and introduce oxygen, and react at 100-150°C for 3-10 hours to introduce ester groups into the polyethylene chain through the Baeyer-Villiger oxidation reaction. Then pour the reaction solution into ethanol to precipitate oxidized polyethylene, wherein the mass ratio of the waste polyethylene material to the oxidant is 1:1-10, or the mass ratio of the waste polyethylene material to the catalyst is 1:0.05-0.1, and the flow rate of oxygen is 10-20 mL / min.

[0007] (2) The obtained oxidized polyethylene is reacted with an ester degradation reagent The mixture is mixed and reacted at 80-180°C for 3-8 hours to degrade the ester group, and then the reaction solution is poured into water to precipitate the telechelic degradation product of the waste polyethylene, wherein the mass ratio of the oxidized polyethylene to the ester degradation reagent is 1:5-10.

[0008] (3) Referring to the method disclosed in the prior art, the hydroxyl groups in the obtained telechelic degradation products of waste polyethylene are modified into aldehyde groups by esterification reaction using p-formylbenzoic acid, and the modified degradation products are further mixed with flame retardant or antistatic dyeing functional monomers containing amino groups in a ratio of 1:1 between aldehyde groups and amino groups in solvent II, and reacted at 40-60°C for 3-6 hours to achieve the combination of the degradation products and the functional monomers through dynamic imine bonds, and obtain new materials with functional and high performance.

[0009] The reaction equation of the above degradation method is as follows:

[0010] The waste polyethylene material described in the above method is any one of waste low-density polyethylene material, waste high-density polyethylene material and waste linear low-density polyethylene material.

[0011] The solvent I described in the above method is any one of toluene, xylene, chlorobenzene and tetrachloroethane.

[0012] The oxidant described in the above method is any one of meta-chloroperbenzoic acid, perbenzoic acid and peracetic acid.

[0013] The catalyst in the above method is any one of cobalt acetate, cobalt chloride, cobalt bromide, cobalt sulfate and cobalt nitrate.

[0014] The ester degradation reagent described in the above method Any of ethylene glycol, propylene glycol, butylene glycol and ethanolamine.

[0015] The telechelic degradation product obtained in the above method has a weight average molecular weight of 500-10000 g / mol.

[0016] The method disclosed in the prior art described in the above method is the method disclosed in Soft Matter, 2011, 7, 6144.

[0017] The structure of the amino-containing flame retardant or antistatic dyeing functional monomer described in the above method is as follows:

[0018] The solvent II described in the above method is any one of tetrahydrofuran, dioxane, chloroform and dichloromethane.

[0019] The new material obtained by the above method has a tensile strength of 10-30 MPa and an elongation at break of 100-400%.

[0020] The limiting oxygen index of the new material obtained by the above method is 23-30%, and the volume resistivity is 10 9 -1012 Ω*cm, dyeing rate is 15-30%.

[0021] Compared with the prior art, the method provided by the present invention produces the following beneficial technical effects: 1. Since the method provided by the present invention can first perform a two-step oxidative degradation of waste polyethylene, that is, the method introduces ester groups into the polyethylene backbone through a Baeyer-Villiger oxidation reaction, and then obtains telechelic degradation products through degradation of the ester groups, it is not only possible to conveniently control the weight-average molecular weight of the degradation products within the range of 500-10000 g / mol by controlling the amount of ester groups introduced, but also to lay a good variable foundation for the subsequent functional high-performance reconstruction of the degradation products and reduce costs.

[0022] 2. Since the method provided by the present invention is based on obtaining a telechelic degradation product through the degradation of ester groups, and then subsequently modifies it to reconstruct a high-performance / functional dynamic cross-linked network, the mechanical properties of the reconstructed new material are greatly enhanced compared to the original polyethylene, solving the problem of poor performance of the reconstructed material obtained by linear polymerization in the existing technology.

[0023] 3. Since the method provided by the present invention also introduces a variety of functional monomers, such as flame retardant monomers and antistatic chromogens, when reconstructing the high-performance / functional dynamic cross-linking network of telechelic degradation products, the reconstructed new materials are given a variety of applications in the fields of flame retardancy, antistatic, dyeing, etc., thereby improving the use value of the reconstructed new materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The telechelic degradation product prepared in Example 3 of the present invention 1 H-NMR spectrum. The figure shows that there are obvious signal peaks of terminal hydroxyl groups in the degradation products, indicating that polyethylene is successfully degraded into telechelic degradation products.

[0025] Figure 2 The tensile strength curves of the reconstructed material and original LDPE prepared in Example 13 of the present invention are shown in Figure 13. The comparison shows that the mechanical properties of the reconstructed material are significantly better than those of the original LDPE, demonstrating that the present invention can enhance the mechanical properties of polyethylene waste, thereby increasing the value of the reconstructed material. DETAILED DESCRIPTION

[0026] The following examples provide a clearer and more complete description of the technical solution for the oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials provided by the present invention. It is important to note that the following examples are intended only to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Based on the above disclosure, non-essential improvements and adjustments made by persons skilled in the art to the present invention for specific implementation remain within the scope of protection of the present invention.

[0027] It is worth noting that 1) the aldehyde-modified telechelic degradation product was prepared according to the prior art method disclosed in Soft Matter, 2011, 7, 6144. Specifically, the following steps were performed: 10 parts by weight of the telechelic degradation product, 5 parts by weight of p-carboxybenzaldehyde, 10 parts by weight of N,N'-dicyclohexylcarboximide, and 0.2 parts by weight of 4-dimethylaminopyridine were dissolved in tetrahydrofuran and reacted at 60°C for 24 hours. After the reaction, a large amount of ethanol was added to precipitate the aldehyde-modified telechelic degradation product. 2) The reconstructed material was prepared into 0.85 × 5 cm dumbbell-shaped specimens. The tensile strength and elongation at break of the reconstructed material were measured using an INSTRON 3366 electronic universal materials testing machine at a tensile rate of 5 mm / min. 3) The limiting oxygen index of the reconstructed material was measured according to the national standard GB / T 2406. 4) The volume resistivity of the reconstructed material was measured on an ST2643 ultra-high resistance microcurrent tester. 5) The dye uptake of the reconstructed material was tested according to the following steps: a 15×15×0.3 mm sample was placed in 10 mL of 0.5 g / mL methylene blue dye solution and dyed for 4 h. After dyeing, the sample was taken out and washed four times with water, 5 mL each time, and the washing liquid was combined with the dye solution, which was then diluted 5 times. At the same time, the original dye solution was diluted 15 times with water. The absorbance of the dye solution at 664 nm before and after dyeing was measured using a UV-visible spectrophotometer, and the dye uptake was calculated. The formula for calculating the dye uptake is: dye uptake = (A0-A1) / A0*100%, where A0 and A1 are the absorbance of the dye solution at 664 nm before and after dyeing. 6) The tensile strength of the waste LDPE used in the following examples is 7.5 MPa, the elongation at break is 80%, the limiting oxygen index is 18%, and the volume resistivity is 2.1×10 14 Ω·cm, dye uptake is 0%; the tensile strength of waste LLDPE is 13 MPa, the elongation at break is 720%, the limiting oxygen index is 18%, and the volume resistivity is 3.3×10 14 Ω·cm, dye uptake rate is 0%; the tensile strength of waste HDPE is 25 MPa, the elongation at break is 170%, the limiting oxygen index is 18%, and the volume resistivity is 5.4×10 14 Ω·cm, dye uptake is 0%.

[0028] Example 1

[0029] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 10 parts of m-chloroperbenzoic acid were added. The mixture was heated at 100°C for 3 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethylene glycol and reacted at 80°C for 3 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 10,000 g / mol.

[0030] The degradation product of the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art, and the degradation product was mixed with the functional monomer TAPPP in a ratio of aldehyde group to amino group of 1:1 in tetrahydrofuran, and reacted at 60°C for 3 h to be reconstructed through dynamic imine bonds.

[0031] The reconstructed material has a tensile strength of 10 MPa, an elongation at break of 370%, and a limiting oxygen index of 23%.

[0032] Example 2

[0033] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 0.5 parts of cobalt acetate were added. Oxygen was continuously introduced at a flow rate of 10 mL / min, and the mixture was heated at 100°C for 5 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of ethanolamine and reacted at 90°C for 5 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain a telechelic degradation product of waste polyethylene with a weight-average molecular weight of 7000 g / mol.

[0034] The degradation products of telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, mixed with the functional monomer [Lys][N4444] in a ratio of aldehyde group to amino group of 1:1 in dioxane, and reacted at 60 °C for 3 h to reconstruct through dynamic imine bond.

[0035] The reconstructed material has a tensile strength of 13 MPa, an elongation at break of 350%, and a volume resistivity of 1.0×10 12 Ω·cm, dyeing rate is 15%.

[0036] Example 3

[0037] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 80 parts of perbenzoic acid were added. The mixture was heated at 120°C for 7 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of ethanolamine and reacted at 120°C for 8 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 500 g / mol.

[0038] The degradation products of the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, and the degradation products were mixed with the functional monomer TATOTA in a ratio of aldehyde group to amino group of 1:1 in dichloromethane and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0039] The reconstructed material has a tensile strength of 30 MPa, an elongation at break of 100%, and a limiting oxygen index of 30%.

[0040] Example 4

[0041] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 1 part of cobalt chloride was added. Oxygen was continuously introduced at a flow rate of 15 mL / min, and the mixture was heated at 110°C for 3 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of butanediol and reacted at 110°C for 6 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 8500 g / mol.

[0042] The degradation products of telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, mixed with the functional monomer [Lys][P4444] in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 55 °C for 3 h to reconstruct through dynamic imine bond.

[0043] The reconstructed material has a tensile strength of 12 MPa, an elongation at break of 360%, and a volume resistivity of 7.3×10 11 Ω·cm, dyeing rate is 21%.

[0044] Example 5

[0045] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 70 parts of peracetic acid were added. The mixture was heated at 100°C for 8 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 100 parts of propylene glycol and reacted at 130°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1000 g / mol.

[0046] The degradation products of the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, and the degradation products were mixed with the functional monomer TAPPHA in a ratio of aldehyde group to amino group of 1:1 in dichloromethane and reacted at 45°C for 5 h to reconstruct through dynamic imine bonds.

[0047] The reconstructed material has a tensile strength of 28 MPa, an elongation at break of 150%, and a limiting oxygen index of 27%.

[0048] Example 6

[0049] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 40 parts of m-chloroperbenzoic acid were added. The mixture was heated at 100°C for 8 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 90 parts of ethanolamine and reacted at 140°C for 4 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 5400 g / mol.

[0050] The degradation products of telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, mixed with the functional monomer [Lys][emim] in a ratio of aldehyde group to amino group of 1:1 in tetrahydrofuran, and reacted at 50°C for 4 h to reconstruct through dynamic imine bond.

[0051] The reconstructed material has a tensile strength of 20 MPa, an elongation at break of 230%, and a volume resistivity of 4.3×10 11 Ω·cm, dyeing rate is 25%.

[0052] Example 7

[0053] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 40 parts of peracetic acid were added. The mixture was heated at 110°C for 10 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 70 parts of ethylene glycol and reacted at 160°C for 5 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 2400 g / mol.

[0054] The degradation products of the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, and the degradation products were mixed with the functional monomer TAPPP in a ratio of aldehyde group to amino group of 1:1 in dichloromethane and reacted at 45 °C for 5 h to reconstruct through dynamic imine bonds.

[0055] The reconstructed material has a tensile strength of 25 MPa, an elongation at break of 220%, and a limiting oxygen index of 25%.

[0056] Example 8

[0057] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 80 parts of m-chloroperbenzoic acid were added. The mixture was heated at 130°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of propylene glycol and reacted at 100°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1200 g / mol.

[0058] The degradation products of the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art, and mixed with the functional monomer [Lys][Py4] in a ratio of aldehyde group to amino group of 1:1 in dichloromethane and reacted at 40 °C for 6 h to reconstruct through dynamic imine bond.

[0059] The reconstructed material has a tensile strength of 30 MPa, an elongation at break of 200%, and a volume resistivity of 6.5×10 9 Ω·cm, dyeing rate is 30%.

[0060] Example 9

[0061] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 60 parts of perbenzoic acid were added. The mixture was heated at 150°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of butanediol and reacted at 130°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1800 g / mol.

[0062] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer TATOTA in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0063] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 210%, and a limiting oxygen index of 29%.

[0064] Example 10

[0065] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 0.8 parts of cobalt bromide was added. Oxygen was continuously introduced at a flow rate of 20 mL / min, and the mixture was heated at 150°C for 10 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 100 parts of ethanolamine and reacted at 170°C for 3 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 6700 g / mol.

[0066] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][N4444] in a ratio of aldehyde group to amino group of 1:1 in dioxane, and reacted at 50°C for 6 h to reconstruct through dynamic imine bond.

[0067] The reconstructed material has a tensile strength of 19 MPa, an elongation at break of 280%, and a volume resistivity of 5.4×10 11 Ω·cm, dyeing rate is 18%.

[0068] Example 11

[0069] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 1 part of cobalt sulfate was added. Oxygen was continuously introduced at a flow rate of 10 mL / min, and the mixture was heated at 100°C for 8 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of propylene glycol and reacted at 180°C for 8 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 4300 g / mol.

[0070] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer TAPPHA in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 50°C for 4 h to reconstruct through dynamic imine bonds.

[0071] The reconstructed material has a tensile strength of 21 MPa, an elongation at break of 300%, and a limiting oxygen index of 25%.

[0072] Example 12

[0073] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 90 parts of m-chloroperbenzoic acid were added. The mixture was heated at 140°C for 6 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethylene glycol and reacted at 150°C for 4 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1500 g / mol.

[0074] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer [Lys][P4444] in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0075] The reconstructed material has a tensile strength of 24 MPa, an elongation at break of 260%, and a volume resistivity of 1.0×10 9 Ω·cm, dyeing rate is 28%.

[0076] Example 13

[0077] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 100 parts of peracetic acid were added. The mixture was heated at 100°C for 4 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of ethylene glycol and reacted at 110°C for 6 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 2300 g / mol.

[0078] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TAPPP in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 45°C for 6 hours to reconstruct through dynamic imine bonds.

[0079] The reconstructed material has a tensile strength of 25 MPa, an elongation at break of 280%, and a limiting oxygen index of 27%.

[0080] Example 14

[0081] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 0.7 parts of cobalt acetate was added. Oxygen was continuously introduced at a flow rate of 15 mL / min, and the mixture was heated at 110°C for 6 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 70 parts of ethanolamine and reacted at 130°C for 5 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 6400 g / mol.

[0082] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer [Lys][emim] in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 50°C for 4 h to reconstruct through the dynamic imine bond.

[0083] The reconstructed material has a tensile strength of 15 MPa, an elongation at break of 350%, and a volume resistivity of 4.3×10 10 Ω·cm, dyeing rate is 23%.

[0084] Example 15

[0085] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 0.5 parts of cobalt acetate were added. Oxygen was continuously introduced at a flow rate of 20 mL / min, and the mixture was heated at 100°C for 5 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 100 parts of ethanolamine and reacted at 80°C for 7 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 9300 g / mol.

[0086] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TATOTA in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 60°C for 3 h to reconstruct through dynamic imine bonds.

[0087] The reconstructed material has a tensile strength of 10 MPa, an elongation at break of 400%, and a limiting oxygen index of 23%.

[0088] Example 16

[0089] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 60 parts of perbenzoic acid were added. The mixture was heated at 100°C for 7 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of butanediol and reacted at 130°C for 4 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 4300 g / mol.

[0090] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][Py4] in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 50°C for 5 h to reconstruct through dynamic imine bond.

[0091] The reconstructed material has a tensile strength of 17 MPa, an elongation at break of 330%, and a volume resistivity of 7.5×10 10 Ω·cm, dyeing rate is 20%.

[0092] Example 17

[0093] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 100 parts of peracetic acid were added. The mixture was heated at 130°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of ethylene glycol and reacted at 90°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1400 g / mol.

[0094] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer TAPPHA in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0095] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 240%, and a limiting oxygen index of 29%.

[0096] Example 18

[0097] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 0.5 parts of cobalt chloride were added. Oxygen was continuously introduced at a flow rate of 10 mL / min, and the mixture was heated at 130°C for 10 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethanolamine and reacted at 140°C for 5 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 6500 g / mol.

[0098] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][N4444] in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 50°C for 4 h to reconstruct through dynamic imine bond.

[0099] The reconstructed material has a tensile strength of 15 MPa, an elongation at break of 350%, and a volume resistivity of 4.7×10 10 Ω·cm, dyeing rate is 25%.

[0100] Example 19

[0101] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 50 parts of m-chloroperbenzoic acid were added. The mixture was heated at 130°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of propylene glycol and reacted at 90°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1300 g / mol.

[0102] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TAPPP in dichloromethane at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 hours to reconstruct through dynamic imine bonds.

[0103] The reconstructed material has a tensile strength of 27 MPa, an elongation at break of 200%, and a limiting oxygen index of 30%.

[0104] Example 20

[0105] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 50 parts of peracetic acid were added. The mixture was heated at 100°C for 7 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 70 parts of propylene glycol and reacted at 110°C for 6 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1100 g / mol.

[0106] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer [Lys][P4444] in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0107] The reconstructed material has a tensile strength of 28 MPa, an elongation at break of 150%, and a volume resistivity of 2.8×10 9 Ω·cm, dyeing rate is 30%.

[0108] Example 21

[0109] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 70 parts of perbenzoic acid were added. The mixture was heated at 150°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of butanediol and reacted at 120°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1900 g / mol.

[0110] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer TATOTA in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0111] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 210%, and a limiting oxygen index of 29%.

[0112] Example 22

[0113] First, 10 parts of waste low-density polyethylene were dissolved in xylene, and then 30 parts of peracetic acid were added. The mixture was heated at 100°C for 6 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of propylene glycol and reacted at 140°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1300 g / mol.

[0114] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer [Lys][emim] in dichloromethane at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through the dynamic imine bond.

[0115] The reconstructed material has a tensile strength of 30 MPa, an elongation at break of 150%, and a volume resistivity of 2.6×10 9 Ω·cm, dyeing rate is 28%.

[0116] Example 23

[0117] First, 10 parts of waste low-density polyethylene were dissolved in toluene, and then 90 parts of peracetic acid were added. The mixture was heated at 100°C for 4 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethylene glycol and reacted at 120°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 2200 g / mol.

[0118] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer TAPPHA in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 45°C for 5 h to reconstruct through dynamic imine bonds.

[0119] The reconstructed material has a tensile strength of 28 MPa, an elongation at break of 280%, and a limiting oxygen index of 27%.

[0120] Example 24

[0121] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 70 parts of perbenzoic acid were added. The mixture was heated at 120°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 70 parts of ethanolamine and reacted at 130°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 800 g / mol.

[0122] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][Py4] in a ratio of aldehyde group to amino group of 1:1 in dichloromethane, and reacted at 40°C for 6 h to reconstruct through dynamic imine bond.

[0123] The reconstructed material has a tensile strength of 30 MPa, an elongation at break of 100%, and a volume resistivity of 1.5×10 9 Ω·cm, dyeing rate is 30%.

[0124] Example 25

[0125] First, 10 parts of waste linear low-density polyethylene were dissolved in chlorobenzene, and then 50 parts of m-chloroperbenzoic acid were added. The mixture was heated at 120°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 70 parts of ethanolamine and reacted at 120°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1400 g / mol.

[0126] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TAPPP in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0127] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 210%, and a limiting oxygen index of 28%.

[0128] Example 26

[0129] First, 10 parts of waste linear low-density polyethylene were dissolved in chlorobenzene, and then 1 part of cobalt bromide was added. Oxygen was continuously introduced at a flow rate of 15 mL / min, and the mixture was heated at 100°C for 6 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethylene glycol and reacted at 150°C for 4 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1900 g / mol.

[0130] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][N4444] in chloroform at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bond.

[0131] The reconstructed material has a tensile strength of 25 MPa, an elongation at break of 250%, and a volume resistivity of 3.7×10 9 Ω·cm, dyeing rate is 23%.

[0132] Example 27

[0133] First, 10 parts of waste low-density polyethylene were dissolved in chlorobenzene, and then 50 parts of m-chloroperbenzoic acid were added. The mixture was heated at 140°C for 7 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 90 parts of propylene glycol and reacted at 140°C for 4 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1800 g / mol.

[0134] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TATOTA in a ratio of aldehyde group to amino group of 1:1 in dichloromethane, and reacted at 40°C for 6 hours to reconstruct through dynamic imine bonds.

[0135] The reconstructed material has a tensile strength of 24 MPa, an elongation at break of 260%, and a limiting oxygen index of 28%.

[0136] Example 28

[0137] First, 10 parts of waste linear low-density polyethylene were dissolved in toluene, and then 60 parts of peracetic acid were added. The mixture was heated at 100°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 10 parts of ethylene glycol and reacted at 110°C for 6 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 2500 g / mol.

[0138] First, the telechelic degradation products of waste polyethylene were modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation products were mixed with the functional monomer [Lys][P4444] in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 h to reconstruct through dynamic imine bonds.

[0139] The reconstructed material has a tensile strength of 25 MPa, an elongation at break of 280%, and a volume resistivity of 3.4×10 9 Ω·cm, dyeing rate is 30%.

[0140] Example 29

[0141] First, 10 parts of waste high-density polyethylene were dissolved in xylene, and then 40 parts of m-chloroperbenzoic acid were added. The mixture was heated at 150°C for 6 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 80 parts of ethanolamine and reacted at 130°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 6500 g / mol.

[0142] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer TAPPHA in tetrahydrofuran at a ratio of aldehyde group to amino group of 1:1, and reacted at 50°C for 4 h to reconstruct through dynamic imine bonds.

[0143] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 330%, and a limiting oxygen index of 25%.

[0144] Example 30

[0145] First, 10 parts of waste high-density polyethylene were dissolved in chlorobenzene, and then 0.5 parts of cobalt sulfate were added. Oxygen was continuously introduced at a flow rate of 20 mL / min, and the mixture was heated at 150°C for 3 h for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 60 parts of butanediol and reacted at 160°C for 5 h to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 7300 g / mol.

[0146] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. The modified degradation product was then mixed with the functional monomer [Lys][emim] in a ratio of aldehyde group to amino group of 1:1 in dioxane, and reacted at 55°C for 3 h to reconstruct through a dynamic imine bond.

[0147] The reconstructed material has a tensile strength of 26 MPa, an elongation at break of 300%, and a volume resistivity of 8.5×10 11 Ω·cm, dyeing rate is 25%.

[0148] Example 31

[0149] First, 10 parts of waste high-density polyethylene were dissolved in chlorobenzene, and then 50 parts of m-chloroperbenzoic acid were added. The mixture was heated at 130°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of propylene glycol and reacted at 90°C for 5 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 2000 g / mol.

[0150] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer TAPPP in dichloromethane at a ratio of aldehyde group to amino group of 1:1, and reacted at 40°C for 6 hours to reconstruct through dynamic imine bonds.

[0151] The reconstructed material has a tensile strength of 28 MPa, an elongation at break of 220%, and a limiting oxygen index of 29%.

[0152] Example 32

[0153] First, 10 parts of waste high-density polyethylene were dissolved in chlorobenzene, and then 70 parts of m-chloroperbenzoic acid were added. The mixture was heated at 130°C for 5 hours for oxidation reaction. The resulting reaction solution was then poured into ethanol to precipitate oxidized polyethylene, which was filtered, washed with ethanol, and dried. 10 parts of oxidized polyethylene were mixed with 50 parts of ethanolamine and reacted at 100°C for 7 hours to degrade the ester group. The resulting degradation solution was then poured into water to precipitate the degradation product, which was filtered, washed with water, and dried to obtain the telechelic degradation product of waste polyethylene with a weight-average molecular weight of 1800 g / mol.

[0154] First, the telechelic degradation product of waste polyethylene was modified with aldehyde groups according to the method disclosed in the prior art. Then, the modified degradation product was mixed with the functional monomer [Lys][Py4] in a ratio of aldehyde group to amino group of 1:1 in dichloromethane, and reacted at 40°C for 6 h to reconstruct through dynamic imine bond.

[0155] The reconstructed material has a tensile strength of 30 MPa, an elongation at break of 200%, and a volume resistivity of 3.9×10 9 Ω·cm, dyeing rate is 28%.

Claims

1. A method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials, the process steps and conditions of the method are as follows: (1) Dissolve the waste polyethylene material in solvent I under heating conditions, then add an oxidant, or add a catalyst and introduce oxygen, and react at 100-150°C for 3-10 hours to introduce ester groups into the polyethylene chain through the Baeyer-Villiger oxidation reaction, and then pour the reaction solution into ethanol to precipitate oxidized polyethylene, wherein: The mass ratio of waste polyethylene material to oxidant is 1:1-10, or the mass ratio of waste polyethylene material to catalyst is 1:0.05-0.1, and the oxygen flow rate is 10-20 mL / min; (2) The obtained oxidized polyethylene is reacted with an ester degradation reagent Mixing, reacting at 80-180°C for 3-8 hours to degrade the ester group, and then pouring the reaction solution into water to precipitate the telechelic degradation product of the waste polyethylene, wherein the mass ratio of the oxidized polyethylene to the ester degradation reagent is 1:5-10; (3) Referring to the method disclosed in the prior art, the hydroxyl groups in the obtained telechelic degradation products of waste polyethylene are modified into aldehyde groups by esterification reaction using p-formylbenzoic acid, and the modified degradation products are further mixed with flame retardant or antistatic dyeing functional monomers containing amino groups in a ratio of 1:1 between aldehyde groups and amino groups in solvent II, and reacted at 40-60°C for 3-6 hours to achieve the combination of the degradation products and the functional monomers through dynamic imine bonds, and obtain new materials with functional and high performance.

2. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 1, wherein the waste polyethylene material is any one of waste low-density polyethylene material, waste high-density polyethylene material and waste linear low-density polyethylene material.

3. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 1 or 2, wherein the solvent I in step (1) of the method is any one of toluene, xylene, chlorobenzene and tetrachloroethane; the oxidant is any one of m-chloroperbenzoic acid, perbenzoic acid and peracetic acid; and the catalyst is any one of cobalt acetate, cobalt chloride, cobalt bromide, cobalt sulfate and cobalt nitrate.

4. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 1 or 2, wherein the ester degradation reagent in step (2) of the method It is any one of ethylene glycol, propylene glycol, butylene glycol and ethanolamine.

5. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 3, wherein the ester degradation reagent in step (2) of the method It is any one of ethylene glycol, propylene glycol, butylene glycol and ethanolamine.

6. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 1 or 2, wherein the structure of the amino-containing flame retardant or antistatic dyeing functional monomer in step (3) is as follows: ； The solvent II is any one of tetrahydrofuran, dioxane, chloroform and dichloromethane.

7. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 3, wherein the structure of the amino-containing flame retardant or antistatic dyeing functional monomer in step (3) is as follows: ； The solvent II is any one of tetrahydrofuran, dioxane, chloroform and dichloromethane.

8. The method for oxidative degradation recovery and functional / high-performance reconstruction of waste polyethylene materials according to claim 5, wherein the structure of the amino-containing flame retardant or antistatic dyeing functional monomer in step (3) is as follows: ； The solvent II is any one of tetrahydrofuran, dioxane, chloroform and dichloromethane.

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