A preparation method and preparation device of glass-like polyolefin material tube

Abstract

The present invention discloses a method and apparatus for preparing a glass-like polyolefin material tube. The method comprises the following steps: mixing raw materials (polyolefin, initiator, and electron-rich monomer), respectively mixing with a carboxyl-containing grafting monomer and an epoxy-containing grafting monomer, and then melt-plasticizing. Carboxyl-functionalized grafted polyolefin and epoxy-functionalized grafted polyolefin are simultaneously extruded through a grafting reaction to prepare carboxyl-functionalized grafted polyolefin and epoxy-functionalized grafted polyolefin; adding the two functionalized polyolefins in a predetermined mass ratio into a conical twin-screw extruder for hot melt mixing; adding a catalyst through the exhaust port for reaction and extrusion to obtain a glass-like polyolefin material; and shaping the obtained glass-like polyolefin material through a pipe die to obtain a glass-like polyolefin tube. The material has stable performance at room temperature and can be recycled and reused by heating. The preparation method is simple and easy to implement, making it suitable for large-scale industrial production.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer material processing, and in particular relates to a preparation method and a preparation device of a glass-like polyolefin material tube. Background Art

[0002] Polyolefins are widely used, but their applications are limited by their sensitivity to environmental stresses, poor heat resistance, and poor mechanical properties. Therefore, chemical cross-linking is often used to modify the molecular chain topology of polyolefins to improve their physical and chemical properties. Chemically cross-linked polyolefins can withstand higher thermal loads and exhibit improved oil and aging resistance, mechanical properties, and electrical performance, making them widely used in industries such as electrical, construction, and automotive.

[0003] Traditional methods for preparing chemically cross-linked polyolefins include radiation, peroxide, and silane cross-linking. However, these methods suffer from poor process controllability, difficulty melting upon heating, and difficulty recycling, resulting in difficult recycling and low reuse rates. Furthermore, many recycling technologies struggle to specifically destroy or alter the three-dimensional network structure of cross-linked polyolefins, resulting in unstable performance and low recyclability of recycled waste cross-linked polyolefins.

[0004] The preparation of recyclable cross-linked polyolefin materials has become one of the hot areas for future development. Patent CN113045704A proposes a polyolefin reversibly cross-linked network material and its preparation method: polyolefin, anhydride compound, polyol, free radical initiator and antioxidant are uniformly mixed and then granulated using a twin-screw extruder, and the granulated material is solidified and annealed to prepare the polyolefin reversible cross-linked network material. The difficult-to-control pre-cross-linking reaction during the preparation process of this method will have an adverse effect on the performance of the product. In addition, the curing and annealing processes are cumbersome, which limits its industrial adaptability. Patents CN201480024950.6 and CN201680020969.2 both propose a cross-linked polyolefin tube. However, the radiation cross-linking method they use is limited by the intensity of radiation, has poor controllability, and is almost impossible to reshape and shape, which seriously damages the physical and chemical properties of the recycled material. Summary of the Invention

[0005] To address the aforementioned technical problems existing in the prior art, the present invention provides a method and apparatus for preparing recyclable glass-like polyolefin tubes. The recyclable glass-like polyolefin material prepared using the method of the present invention exhibits excellent remolding properties, with a viscosity-temperature relationship similar to that of glass during remolding, and a room-temperature physical property loss rate of less than 10%. Furthermore, compared to traditional polyolefin materials, this material exhibits significant improvements in shrinkage, dimensional stability, heat and aging resistance, and mechanical properties. Furthermore, the reaction is stable and controllable, and the equipment requirements are simple, making it more suitable for industrial production.

[0006] A first aspect of the present invention provides a method for preparing a glass-like polyolefin material tube, comprising the following steps:

[0007] (1) mixing the following raw materials in parts by weight: 100 parts of polyolefin, 0.1-5 parts of initiator, and 0.5-25 parts of electron-rich monomer, and respectively mixing with 0.1-20 parts of carboxyl-containing grafting monomer and 0.1-20 parts of epoxy-containing grafting monomer, melt-plasticizing and synchronously extruding in a parallel co-rotating twin-screw extruder through grafting reaction to prepare carboxyl functional group grafted polyolefin and epoxy functional group grafted polyolefin;

[0008] (2) hot-melt mixing the carboxyl functional group grafted polyolefin and the epoxy functional group grafted polyolefin obtained in step (1) at a set mass ratio at 90-130° C. and then adding the mixture to a conical twin-screw extruder with a vent;

[0009] (3) adding 0.05-10 parts of a catalyst to the hot melt mixture in step (2) through the exhaust port of a conical twin-screw extruder, reacting and extruding to obtain a glass-like polyolefin material, and shaping the plasticized glass-like polyolefin material through a pipe assembly to obtain a glass-like polyolefin pipe product, wherein the cross-linked network structure density of the glass-like polyolefin pipe product can be adjusted by temperature control.

[0010] Optionally, the set mass ratio of the carboxyl functional group grafted polyolefin to the epoxy functional group grafted polyolefin in the hot melt mixing is 0.2-5.

[0011] Optionally, the polyolefin is a combination of one or more of polyethylene, polypropylene, polybutene and copolymers thereof, or a combination of one or more of polyethylene, polypropylene, polybutene and blends thereof, and is not limited thereto; the initiator is a combination of one or more of organic peroxide initiators and azo initiators, and is not limited thereto; the electron-rich monomer is a combination of one or more of styrene, acrylamide, methyl acrylate and ethyl acrylate, and is not limited thereto.

[0012] Optionally, the carboxyl-containing grafting monomer is a combination of one or more of maleic acid, itaconic acid, acrylic acid, methacrylic acid, ethacrylic acid and other alkyl acrylic acids, but is not limited thereto.

[0013] Optionally, the epoxy-containing grafting monomer is a combination of one or more of glycidyl methacrylate and epoxybutene, but is not limited thereto.

[0014] Optionally, the catalyst includes one or more combinations of zinc acetate, zinc acetylacetonate, acrylonitrile and zinc acrylate copolymer, sodium methoxide, sodium hydroxide, potassium hydroxide, primary amine, secondary amine, and tertiary amine, but is not limited thereto.

[0015] The cross-linked network structure of the glass-like polyolefin tube can be rebuilt multiple times by breaking and generating reversible chemical bonds.

[0016] The cross-linked network structured glass-like polyolefin tubular product can maintain more than 90% of the physical and chemical performance indexes of the original product after being recycled, melt-plasticized and secondary molded.

[0017] The glass-like polyolefin material obtained according to any of the above preparation methods is characterized in that the prepared glass-like polyolefin material is blended and plasticized with a polyolefin material to form a product with a cross-linked interlocking microstructure after extrusion.

[0018] Optionally, the equipment for blending, extrusion, recycling and reuse includes: dedicated single-screw extrusion equipment or conical twin-screw extrusion equipment.

[0019] The second aspect of the present invention provides a device for preparing a glass-like polyolefin material tube, comprising a parallel co-rotating twin-screw extruder and a conical twin-screw extruder, the parallel co-rotating twin-screw extruder comprising: a first parallel co-rotating twin-screw extruder and a second parallel co-rotating twin-screw extruder; the output end of the first parallel co-rotating twin-screw extruder and the output end of the second parallel co-rotating twin-screw extruder are connected to the input end of the conical twin-screw extruder after merging; the output end of the conical twin-screw extruder is connected to a pipe assembly, the pipe assembly comprising: a tube blank mold and a shaping mold, and a traction device is installed at the corresponding position on the rear side of the shaping mold.

[0020] The present invention also provides a glass-like polyolefin material tube obtained by the above technical solution.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention can produce a polymer whose cross-linked network structure can be reconstructed multiple times at a specific temperature. The stable network structure at room temperature enables the material to achieve physical and chemical properties comparable to those of traditional cross-linked polyolefins. After recycling, heating and reshaping, the physical and chemical performance indicators of the product can still maintain more than 90% of the original product, making the material have reshaping and recyclability different from traditional cross-linked polyolefins;

[0023] (2) The glass-like polyolefin material of the present invention has the same molding processability as polyolefin, and has better dimensional stability, heat resistance and aging resistance, and mechanical properties than polyolefin. It also has excellent properties such as thermal self-repair, thermal shape memory, and recycling;

[0024] (3) The glass-like polyolefin material and its tubing preparation method provided by the present invention are simple, controllable, and easy to implement, making them suitable for large-scale industrial production. This method is expected to alleviate the resource waste and environmental pollution problems caused by traditional thermosetting materials. By introducing reversible chemical bonds into the polyolefin molecular chain, the glass-like polyolefin material and its tubing exhibit comparable oil resistance, aging resistance, and mechanical properties to those of traditional cross-linked polyolefins. The secondary recycling process also offers similar reshaping properties to thermoplastic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a method for preparing a glass-like polyolefin material tube and a preparation device thereof according to the present invention;

[0026] Figure 2 Schematic diagram of the microstructure of chemically cross-linked polyolefin material mixed with conventional polyolefin;

[0027] Figure 3 Schematic diagram of the microstructure of the glass-like polyolefin material prepared in the present invention mixed with conventional polyolefin.

[0028] Among them, 1-the first parallel co-rotating twin-screw extruder, 2-the second parallel co-rotating twin-screw extruder, 3-the conical twin-screw extruder, 4-the tube blank mold, 5-the shaping mold, and 6-the stretching device. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0030] like Figure 1 As shown, the present invention provides a method for preparing a recyclable glass-like polyolefin material tube, comprising the following steps:

[0031] (1) fully mixing the following raw materials in parts by weight: 100 parts of polyolefin, 0.1-5 parts of initiator, and 0.5-25 parts of electron-rich monomer, and respectively mixing them with 0.1-20 parts of carboxyl-containing grafting monomer and 0.1-20 parts of epoxy-containing grafting monomer, and then simultaneously preparing carboxyl-functional group-grafted polyolefin and epoxy-functional group-grafted polyolefin by melt plasticization and reactive extrusion in a parallel co-rotating twin-screw extruder with a vent through grafting reaction;

[0032] (2) hot-melt mixing the carboxyl functional group grafted polyolefin and the epoxy functional group grafted polyolefin obtained in step (1) at a set mass ratio at 90-130° C. and then adding the mixture to a conical twin-screw extruder with a vent;

[0033] (3) adding 0.05-10 parts of a catalyst to the hot melt mixture in step (2) through the exhaust port of a conical twin-screw extruder, reacting and extruding to obtain a glass-like polyolefin material, and shaping the plasticized glass-like polyolefin material through a pipe assembly to obtain a glass-like polyolefin pipe product, wherein the cross-linked network structure density of the glass-like polyolefin pipe product can be adjusted by temperature control.

[0034] Optionally, the mass ratio of the carboxyl functional group grafted polyolefin and the epoxy functional group grafted polyolefin mixed by hot melt is set to 0.2-5.

[0035] Optionally, the polyolefin is a combination of one or more of polyethylene, polypropylene, polybutylene and copolymers thereof, but is not limited thereto; the initiator is a combination of one or more of organic peroxide initiators and azo initiators, but is not limited thereto; the electron-rich monomer is a combination of one or more of styrene, acrylamide, methyl acrylate and ethyl acrylate, but is not limited thereto.

[0036] Optionally, the organic peroxide initiator includes: a combination of one or more of diisopropylbenzene peroxide, di-tert-butyl peroxyisopropylbenzene, tert-butyl peracetate, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, benzoyl peroxide, and tert-butyl peroxide dicarbonate, and is not limited thereto; the azo initiator includes: a combination of one or more of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile and dimethyl azobisisobutyrate, and is not limited thereto.

[0037] Optionally, the carboxyl-containing grafting monomer is a combination of one or more of maleic acid, itaconic acid, acrylic acid, methacrylic acid, ethacrylic acid and other alkyl acrylic acids, but is not limited thereto.

[0038] Optionally, the epoxy-containing grafting monomer is a combination of one or more of glycidyl methacrylate and epoxybutene, but is not limited thereto.

[0039] Optionally, the catalyst includes one or more combinations of zinc acetate, zinc acetylacetonate, acrylonitrile and zinc acrylate copolymer, sodium methoxide, sodium hydroxide, potassium hydroxide, primary amine, secondary amine, and tertiary amine, but is not limited thereto.

[0040] The cross-linked network structure of the glass-like polyolefin tube can be rebuilt multiple times by breaking and generating reversible chemical bonds.

[0041] The cross-linked network structured glass-like polyolefin tubular product can maintain more than 90% of the physical and chemical performance indexes of the original product after being recycled, melt-plasticized and secondary molded.

[0042] The glass-like polyolefin material prepared according to any of the above preparation methods is blended with a conventional polyolefin material and extruded and plasticized to form a product with a cross-linked interlocking microstructure.

[0043] The present invention also provides a glass-like polyolefin material tube produced according to the above technical solution. The glass-like polyolefin tube has a diameter of 5-150 mm and a wall thickness of 0.5-10 mm. The produced glass-like polyolefin material exhibits a tensile strength of 18-25 MPa, a tensile modulus of 200-350 MPa, and an elongation at break of 200%-400%.

[0044] The recycled and reprocessed glass-like polyolefin material has a tensile strength of 16 to 22 MPa, a tensile modulus of 180 to 320 MPa, and an elongation at break of 180 to 380 percent.

[0045] The glass-like polyolefin material and its pipes have reversible properties at 100-250°C. The dynamic chemical bonds of the glass-like polyolefin associate and exchange at 100-250°C, enabling the reshaping and recycling of cross-linked polyolefin pipes. The material's viscosity-temperature relationship is similar to that of glass, showing a linear relationship.

[0046] From the perspective of the material microstructure principle diagram, after conventional cross-linked materials (taking chemical cross-linked polyethylene as an example) and the material of the present invention (glass-like polyolefin) are blended with conventional polymers (taking polyethylene as an example), the differences in their microstructures are observed. Figure 2 As shown in Figure 2, the cross-linked network structure of conventional chemically cross-linked polyethylene cannot be reconstructed, so the microstructure distribution of the composite after chemically cross-linked polyethylene and polyethylene blending presents an "island" structure; Figure 3 As shown, since the cross-linked network structure of the glass-like polyolefin material can be rebuilt many times, its recycled material can be reshaped, and the microstructure distribution of the composite after blending the glass-like polyolefin with polyethylene presents a cross-linked interlocking structure.

[0047] The process of the present invention is simple, controllable, easy to implement, and suitable for large-scale industrial production, thereby being expected to alleviate the problems of resource waste and environmental pollution caused by traditional thermosetting materials.

[0048] The glass-like polyolefin material and the pipe thereof of the present invention have excellent reprocessability. The glass-like polyolefin material prepared by the present invention can realize the reorganization of the polymer network at a specific temperature, thereby having the ability to be reshaped and extruded.

[0049] In this invention, polyolefins are reacted with monomers containing epoxy groups and monomers containing carboxylic acid groups, respectively, in the presence of a free radical initiator to produce epoxy- and carboxylated polyolefins. An electron-rich comonomer is introduced to prevent self-polymerization of the grafted monomers. A reversible transesterification reaction occurs between the epoxy- and carboxylated polyolefins in the presence of a catalyst, achieving crosslinking. The room-temperature stable crosslinked structure imparts excellent mechanical properties to the polyolefins. The heated rearrangement of the crosslinked network imparts macroscopic fluidity, making it easy to reshape and reprocess.

[0050] Another embodiment of the present invention further provides a glass-like polyolefin material and a pipe thereof for use in the fields of wires and cables, daily necessities, packaging, automobiles, home appliances, or construction.

[0051] Example 1

[0052] (1) 100 parts of low-density polyethylene, 0.1 parts of dicumyl peroxide, 1 part of methyl acrylate, and 0.5 parts of acrylic acid were uniformly mixed and then subjected to reaction extrusion through a parallel co-rotating twin-screw extruder with a screw diameter of 30 mm, an aspect ratio of 38:1, a rotation speed of 130 rpm, and a temperature of 140-140-150-170-170-170-170-170-150-150° C. (from die head to extrusion die) to obtain acrylic acid-grafted low-density polyethylene;

[0053] (2) 100 parts of low-density polyethylene, 0.1 parts of diisopropylbenzene peroxide, 1 part of methyl acrylate, and 1 part of epoxybutene were uniformly mixed and then subjected to reaction extrusion through a parallel co-rotating twin-screw extruder with a screw diameter of 30 mm, an aspect ratio of 38:1, a rotation speed of 130 rpm, and a temperature of 135-140-150-165-170-170-170-165-150-145°C (from die head to extrusion die) to obtain epoxybutene grafted low-density polyethylene;

[0054] (3) Acrylic acid grafted low-density polyethylene and epoxybutene grafted low-density polyethylene were respectively melt-mixed at 90°C in a mass ratio of 1:1 and added into a conical twin-screw extruder with a rotation speed of 100 rpm, a length of 148 mm, a major diameter of 42 mm, a minor diameter of 33 mm, and a temperature of 130-135-145-150-160-160-160-150-145-140°C. During the extrusion process, 1 part of zinc acetate was added from the exhaust port, and the tube was cooled and shaped through an extrusion die with an inner diameter of 70 mm and a wall thickness of 4 mm under the action of a traction machine to obtain a glass-like polyethylene tube.

[0055] After testing, the tensile strength of this type of glass polyethylene pipe is 19.5MPa, the tensile modulus is 268MPa, and the elongation at break is 305%; after secondary processing and molding, the tensile strength of the glass polyethylene is 18.1MPa, the tensile modulus is 249MPa, and the elongation at break is 285%.

[0056] Example 2

[0057] (1) 100 parts of polypropylene, 0.2 parts of azobisisobutyronitrile, 0.1 parts of styrene, and 2 parts of maleic acid were uniformly mixed and then subjected to reactive extrusion through a parallel co-rotating twin-screw extruder with a screw diameter of 30 mm, an aspect ratio of 38:1, a rotation speed of 150 rpm, and a temperature of 180-185-190-195-200-200-200-195-190-180°C (from die head to extrusion die) to obtain maleic acid grafted polypropylene;

[0058] (2) 100 parts of polypropylene, 0.2 parts of azobisisobutyronitrile, 0.1 parts of styrene, and 2 parts of glycidyl methacrylate were uniformly mixed and then subjected to reaction extrusion through a 30 mm parallel co-rotating twin-screw extruder with an aspect ratio of 38:1, a rotation speed of 150 rpm, and a temperature of 180-185-190-195-200-200-200-195-190-180°C (from die head to extrusion die) to obtain glycidyl methacrylate grafted polypropylene;

[0059] (3) Maleic acid grafted polypropylene and glycidyl methacrylate grafted polypropylene were respectively melt-mixed at 110°C in a mass ratio of 1:2 and then added into a conical twin-screw extruder with a rotation speed of 110 rpm, a length of 148 mm, a major diameter of 42 mm, a minor diameter of 33 mm, and a temperature of 140-145-150-165-170-170-170-165-150-140°C. During the extrusion process, 2 parts of zinc acetylacetonate were added from the exhaust port, and the tubes were cooled and shaped through an extrusion die with an inner diameter of 70 mm and a wall thickness of 4 mm under the action of a traction machine to obtain a glass-like polypropylene tube.

[0060] After testing, the tensile strength of this type of glass polypropylene tube is 22.8MPa, the tensile modulus is 316MPa, and the elongation at break is 351%; after secondary processing and molding, the tensile strength of the glass polypropylene tube is 21.6MPa, the tensile modulus is 290MPa, and the elongation at break is 333%.

[0061] Example 3

[0062] (1) 100 parts of polybutene, 0.5 parts of benzoyl peroxide, 2 parts of ethyl acrylate, and 0.5 parts of ethacrylic acid were uniformly mixed and then subjected to reactive extrusion through a parallel co-rotating twin-screw extruder having a screw diameter of 30 mm, an aspect ratio of 38:1, a rotation speed of 125 rpm, and a temperature of 110-120-140-170-170-175-160-160-150-140° C. (from die head to extrusion die) to obtain ethacrylic acid grafted polybutene;

[0063] (2) 100 parts of polybutene, 0.5 parts of benzoyl peroxide, 2 parts of ethyl acrylate, and 1 part of glycidyl methacrylate were uniformly mixed and then subjected to reactive extrusion through a parallel co-rotating twin-screw extruder with a screw diameter of 30 mm, an aspect ratio of 38:1, a rotation speed of 125 rpm, and a temperature of 110-120-140-170-170-175-160-160-150-140°C (from die head to extrusion die) to obtain glycidyl methacrylate grafted polybutene;

[0064] (3) Ethyl acrylate grafted polybutene and glycidyl methacrylate grafted polybutene were respectively melt-mixed at 110°C in a ratio of 5:1 and added into a conical twin-screw extruder with a rotation speed of 95 rpm, a length of 148 mm, a major diameter of 42 mm, a minor diameter of 33 mm, and a temperature of 100-110-120-140-160-170-170-150-140-120°C. During the extrusion process, 1.5 parts of zinc acetate were added from the exhaust port, and the tubes were cooled and shaped through an extrusion die with an inner diameter of 70 mm and a wall thickness of 4 mm under the action of a traction machine to obtain a glass-like polybutene tube.

[0065] After testing, the tensile strength of this type of glass polybutylene tube is 19.2MPa, the tensile modulus is 274MPa, and the elongation at break is 298%; after secondary processing and molding, the tensile strength of the glass polybutylene tube is 17.3MPa, the tensile modulus is 245MPa, and the elongation at break is 269%.

[0066] Example 4

[0067] like Figure 1 As shown, the present invention provides an apparatus for producing a glass-like polyolefin material tube, comprising parallel co-rotating twin-screw extruders. The parallel co-rotating twin-screw extruders include: a first parallel co-rotating twin-screw extruder 1 and a second parallel co-rotating twin-screw extruder 2. The output ends of the first and second parallel co-rotating twin-screw extruders 1 and 2 intersect and are then connected to the input end of a conical twin-screw extruder 3. The output end of the conical twin-screw extruder 3 is connected to a tube assembly. The tube assembly includes a tube blank mold 4 and a converging shaping mold 5. A traction device 6 is mounted at a corresponding position on the rear side of the shaping mold 5. Each of the parallel co-rotating twin-screw extruders and the conical twin-screw extruder is provided with at least one exhaust port.

[0068] Optionally, the co-extrusion recycling and reuse equipment includes a dedicated single-screw extruder or a conical twin-screw extruder. The conical twin-screw extruder is provided with at least one vent. The co-extrusion recycling and reuse equipment is equipped with a tubular die, a calibrating sleeve, a haul-off machine, a cut-to-length cutter, and other devices.

[0069] As can be seen from the above examples, the glass-like polyolefin material and its tubing provided by the present invention exhibit excellent mechanical properties and dimensional stability, while also being reprocessable. Furthermore, compared to conventional polyolefin materials, the glass-like polyolefin material prepared according to the method of the present invention exhibits significant improvements in shrinkage, dimensional stability, heat and aging resistance, and mechanical properties. Furthermore, the reaction is stable and controllable, and the equipment requirements are simple, making it more suitable for industrial production.

[0070] In this specification, references to terms such as "in one embodiment," "in another embodiment," "exemplary," or "in a specific embodiment" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0071] Although the present invention has been described in detail above using general explanations, specific embodiments, and experiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A method for preparing a glass-like polyolefin material tube, characterized in that: The following steps are involved: (1) mixing the following raw materials in parts by weight: 100 parts of polyolefin, 0.1-5 parts of initiator, and 0.5-25 parts of electron-rich monomer, and respectively mixing with 0.1-20 parts of carboxyl-containing grafting monomer and 0.1-20 parts of epoxy-containing grafting monomer, melt-plasticizing and synchronously extruding in a parallel co-rotating twin-screw extruder through grafting reaction to prepare carboxyl functional group grafted polyolefin and epoxy functional group grafted polyolefin; (2) hot-melt mixing the carboxyl functional group grafted polyolefin and the epoxy functional group grafted polyolefin obtained in step (1) at a set mass ratio at 90-130° C. and then adding the mixture to a conical twin-screw extruder with a vent; (3) adding 0.05-10 parts of a catalyst to the hot melt mixture in step (2) through the exhaust port of a conical twin-screw extruder, reacting and extruding to obtain a glass-like polyolefin material, and shaping the plasticized glass-like polyolefin material through a pipe assembly to obtain a glass-like polyolefin pipe product, wherein the cross-linked network structure density of the glass-like polyolefin pipe product can be adjusted by temperature control; The set mass ratio of the carboxyl functional group grafted polyolefin to the epoxy functional group grafted polyolefin is 0.2-5.

2. The method according to claim 1, characterized in that The polyolefin is a combination of one or more of polyethylene, polypropylene, polybutene and copolymers thereof; the initiator is a combination of one or more of organic peroxide initiators and azo initiators; and the electron-rich monomer is a combination of one or more of styrene, acrylamide, methyl acrylate and ethyl acrylate.

3. The method according to claim 1, characterized in that The carboxyl-containing grafting monomer is a combination of one or more of maleic acid, itaconic acid, acrylic acid, methacrylic acid, ethacrylic acid and other alkyl acrylic acids.

4. The method according to claim 1, wherein The epoxy-containing grafting monomer is a combination of one or more of glycidyl methacrylate and epoxybutene.

5. The method according to claim 1, wherein The catalyst includes one or more combinations of zinc acetate, zinc acetylacetonate, acrylonitrile and zinc acrylate copolymer, sodium methoxide, sodium hydroxide, potassium hydroxide, primary amine, secondary amine, and tertiary amine.

6. The method according to claim 1, characterized in that The cross-linked network structure of the glass-like polyolefin tube can be rebuilt multiple times by breaking and generating reversible chemical bonds, and the physical and chemical performance indicators of the product after reconstruction still maintain more than 90% of the original product.

7. The glass-like polyolefin material obtained by the method according to any one of claims 1 to 6, characterized in that: The prepared glass-like polyolefin material is blended with a polyolefin material and plasticized and extruded to form a product with a cross-linked interlocking microstructure.

8. The method according to claim 7, characterized in that The blending extrusion includes: a dedicated single-screw extrusion device or a conical twin-screw extrusion device.

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