A UPE-T material, its preparation method and application

Abstract

This invention discloses a UPE-T material, its preparation method, and its application, belonging to the field of polymer composite materials technology. By mass percentage, it consists of the following raw materials: 5-30% ultra-high molecular weight polyethylene, 30-70% high-density polyethylene, 10-40% PET, 2-5% eutectic solubilizer, and 3-10% flow modifier. The eutectic solubilizer is prepared by modifying montmorillonite or kaolin as a base with interlayer stripping agents and ionic semi-interpenetrating network crosslinking agents. The flow modifier is prepared by graft polymerization of linear low-density polyethylene (LDPE) as a raw material, xylene as a solvent, BPO as an initiator, and methacrylate monomers. The ultra-high molecular weight polyethylene and flow modifier are mixed, cooled, and then high-density polyethylene, PET, and the eutectic solubilizer are added and mixed uniformly in a high-speed mixer. The mixture is then melt-blended using a twin-screw extruder. The obtained UPE-T material is applied to the production of double-walled spiral wound pipes, resulting in pipes with good ring stiffness and ring flexibility.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, specifically to a UPE-T material, its preparation method, and its applications. Background Technology

[0002] Double-wall spiral pipes consist of two layers: the inner layer handles the primary fluid transport, while the outer layer provides additional mechanical strength and environmental protection. Compared to traditional single-layer pipes, double-wall pipes, with their unique structural design, have become a common form of municipal pipeline.

[0003] Ring stiffness and ring flexibility are the most important performance indicators for pipelines because in the application of buried drainage pipes, the pipeline does not bear internal pressure or the pressure is very low, but only external pressure loads (including dynamic and static loads). If the ring stiffness of the pipeline is too small, the pipeline will undergo large deformation and failure, thus failing to guarantee the safe use of the pipeline; if the ring flexibility is too small, the pipeline is prone to damage and leakage during use.

[0004] The commonly used raw materials for existing double-wall spiral pipes are polyethylene and polypropylene. Pipes made from these materials typically have the advantages of good flexibility and low cost, but their strength and ring stiffness are relatively low, limiting their use in certain special applications. To improve the rigidity and strength of the material, ultra-high molecular weight polyethylene (UHMWPE) and PET are used to modify polyethylene or polypropylene. This improves the rigidity of the material without significantly increasing costs, thereby enhancing the rigidity of the pipe. PET has advantages such as high specific strength, aging resistance, and low price, but its different structural morphology compared to polyethylene and polypropylene limits its compatibility. UHMWPE, on the other hand, has good impact resistance and combines strength with excellent high and low temperature resistance, improving the overall performance of polyethylene or polypropylene. However, UHMWPE has poor processing flow, making it difficult to achieve good blending results with polyethylene or polypropylene through general processing methods. Good flow modification is necessary to achieve good mixing with polyethylene or polypropylene.

[0005] To address the above problems, this invention provides a UPE-T material, its preparation method, and its application. Summary of the Invention

[0006] The purpose of this invention is to provide a UPE-T material, its preparation method, and its application. The UPE-T material is applied to the production of double-wall wound pipes, solving the problem of low ring stiffness in existing double-wall wound pipes mentioned in the background art, so that the prepared double-wall wound pipe has better ring stiffness and good ring flexibility.

[0007] To achieve the above objectives, the present invention provides a UPE-T material, which, by mass percentage, is composed of the following raw materials: 5-30% ultra-high molecular weight polyethylene, 30-70% high-density polyethylene, 10-40% PET, 2-5% eutectic solubilizer, and 3-10% flow modifier.

[0008] Preferably, the average molecular weight of the ultra-high molecular weight polyethylene is 2.5 million; the melt index of the high-density polyethylene is 0.1-2, and the density is 0.94-0.95.

[0009] This invention also provides a method for preparing the above-mentioned UPE-T material, comprising the following steps:

[0010] (1) Preparation of eutectic solubilizer:

[0011] The interlayer stripping agent is dissolved in a low-boiling-point solvent and then added to a high-speed mixer for high-speed mixing with mineral fillers having a layered structure. During the mixing process, the temperature is naturally raised to 80°C. After the low-boiling-point solvent evaporates, an ionic semi-interpenetrating network crosslinking agent is added and the mixture is continued for 5 minutes, followed by cooling.

[0012] (2) Preparation of flow modifier:

[0013] Using linear low-density polyethylene as raw material, solvent, initiator and methacrylate monomers are added, and graft polymerization reaction is carried out at 80-90℃ for 3-5 hours. After cooling, the product is precipitated, crushed and dried.

[0014] (3) Preparation of UPE-T materials:

[0015] Ultra-high molecular weight polyethylene and flow modifier were added to a high-speed mixer and mixed for 10 minutes at 80℃-100℃. After cooling, high-density polyethylene, PET and eutectic solubilizer were added and mixed evenly in the high-speed mixer. The mixture was then melt-blended using a twin-screw extruder.

[0016] Preferably, in step (1), the interlayer stripping agent is 2-6% by weight of the mineral filler with a layered structure; and the ionic semi-interpenetrating network crosslinking agent is 3-15% by weight of the mineral filler with a layered structure.

[0017] Preferably, in step (1), the interlayer stripping agent is one of long-chain alkylammonium quaternary ammonium salt or long-chain alkyl sulfonate; the low-boiling point solvent is one of acetone or chloroform; the layered mineral filler is one of montmorillonite or kaolin; and the ionic semi-interpenetrating network crosslinking agent is one of aluminum trichloride, zinc chloride or ferric chloride.

[0018] Preferably, in step (2), the melt index of the linear low-density polyethylene is 20-50.

[0019] Preferably, in step (2), the solvent is xylene; and the initiator is benzoyl peroxide.

[0020] Preferably, in step (2), the methacrylate monomer is any one or more of octadecyl methacrylate, glycidyl methacrylate, butyl methacrylate, and methyl methacrylate.

[0021] Preferably, in step (3), the temperatures of each section of the twin-screw extruder are: 160-180℃ for the feeding section, 230-260℃ for the mixing section, and 220-250℃ for the metering section.

[0022] This invention also provides the application of the aforementioned UPE-T material in the production of double-walled spiral pipes.

[0023] Polyethylene and polyester (PET) are both crystalline polymers; however, polyethylene or polypropylene are non-polar polymers, while PET is a polar polymer, resulting in poor compatibility and difficulty in effective blending. Ultra-high molecular weight polyethylene (UHMWPE) possesses advantages such as high strength and rigidity, but it is difficult to achieve thermoplastic processing under normal processing conditions. Grafting acrylates onto polyethylene can not only reduce its processing viscosity but also act as a compatibility enhancer between polyethylene, polypropylene, and PET. Kaolin and montmorillonite, being flake-like materials, act as nucleating agents for the crystallization of polyethylene, polypropylene, and polyester. Adding nucleating agents that have undergone interlayer exfoliation to the blend system can promote the formation of eutectic crystals between polyolefins and polyesters, thereby achieving good compatibility and improving the physical and mechanical properties of the blend system. Simultaneously adding aluminum trichloride or ferric trichloride allows their metal ions to form a semi-interpenetrating network with the carbonyl groups in polyester and acrylates through electrostatic interactions, further enhancing the stability of the blend system.

[0024] Therefore, the present invention provides a UPE-T material, its preparation method and application. The obtained UPE-T material has good mechanical strength, and when used to produce double-wall wound pipes, it has high ring stiffness and good rigidity and flexibility.

[0025] The technical solution of the present invention will be further described in detail below through embodiments. Detailed Implementation

[0026] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the invention should be considered equivalent substitutions and are included within the scope of protection of the invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims and are all within the scope of protection of the invention.

[0027] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0028] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0029] Unless otherwise specified, the reagents, instruments, and equipment used in this invention are all commonly used by those skilled in the art.

[0030] Example 1

[0031] This embodiment provides a method for preparing UPE-T material, specifically including the following steps:

[0032] (1) Preparation of eutectic solubilizer:

[0033] Dissolve octadecyltrimethylammonium chloride in acetone, then add it to a high-speed mixer containing kaolin and mix at high speed. During the mixing process, the temperature is raised to 80°C. After the acetone has completely evaporated, aluminum trichloride is added and mixing continues for 5 minutes, followed by cooling. The weight of aluminum trichloride added is 3% of the weight of kaolin, and the weight of octadecyltrimethylammonium chloride is 2% of the weight of kaolin.

[0034] (2) Preparation of flow modifier:

[0035] Linear low-density polyethylene with a melt index of 20 was selected as the raw material. Xylene was used as the solvent and BPO (benzoyl peroxide) was used as the initiator. Glycidyl methacrylate, butyl methacrylate, and methyl methacrylate, accounting for 30% of the weight of polyethylene, were added and grafted at 85°C for 4 hours.

[0036] (3) Preparation of UPE-T materials:

[0037] The following components were selected: ultra-high molecular weight polyethylene with an average molecular weight of 250 (25%), high-density polyethylene with a density of 0.95 (40%), PET bottle grade (25%), eutectic accelerator (5%), and flow modifier (5%).

[0038] Ultra-high molecular weight polyethylene and flow modifier were added to a high-speed mixer and mixed at 90°C for 10 minutes. After cooling, high-density polyethylene, PET and eutectic solubilizer were added and mixed at 3000 rpm for 5 minutes. Then, the mixture was melt-blended in a twin-screw extruder.

[0039] The physical properties of the prepared UPE-T material were tested, and the results are as follows:

[0040] The prepared material possesses the following physical properties: melt index 0.2-0.5, tensile strength greater than 35 MPa, flexural strength greater than 40 MPa, and notched impact strength of the cantilever beam greater than 20 KJ / m. 2 .

[0041] The mechanical properties of polyethylene used for pipes are tensile strength of 22-25 MPa, flexural strength of 20-25 MPa, and impact strength of 10-15 KJ / m. 2 The mechanical properties of this material are far superior to the mechanical strength and toughness of ordinary polyethylene.

[0042] The UPET-T material obtained above was used to prepare double-wall spiral wound pipes. The preparation method was as follows: the UPET material was extruded through a twin-screw extruder to form round or square pipes according to the wall thickness requirements. Then, it was stretched and wound on a winding machine, and bonded to produce double-wall spiral wound pipes of various diameters. The extruder temperature was controlled at 250℃. Before winding, the pipe temperature was controlled at 70℃.

[0043] The physical and mechanical properties of the prepared double-walled spiral tube were tested, and the results are as follows.

[0044] Double-wall spiral pipes made from this material have a ring stiffness greater than 12 kN and excellent ring flexibility, without cracking when compressed to more than 50%. Compared to double-wall spiral pipes made from high-density polyethylene, which only achieve a ring stiffness of 8 kN, UPET double-wall spiral pipes exhibit a significantly improved ring stiffness, which can substantially expand the application market for double-wall spiral pipes.

[0045] Example 2

[0046] This embodiment provides a method for preparing UPE-T material. The method for preparing the eutectic solubilizer and flow modifier is the same as in Example 1, and the amount added is also the same as in Example 1. The only difference from Example 1 is that the following are selected: ultra-high molecular weight polyethylene with an average molecular weight of 250 (accounting for 20%), high-density polyethylene with a density of 0.95 (accounting for 45%), PET bottle grade (accounting for 25%), eutectic accelerator (accounting for 5%), and flow modifier (accounting for 5%).

[0047] The physical properties of the prepared UPE-T material were tested, and the results are as follows:

[0048] The UPET material produced by this method has the following physical properties: melt index 0.5-0.8, tensile strength greater than 36 MPa, flexural strength greater than 35 MPa, and notched cantilever beam impact strength greater than 18 KJ / m. 2 The mechanical properties of this material are far superior to the mechanical strength and toughness of ordinary polyethylene.

[0049] The UPE-T material obtained above was used to prepare double-walled wound tubes, and the preparation method was the same as in Example 1.

[0050] The physical and mechanical properties of the prepared double-walled spiral tube were tested, and the results are as follows.

[0051] The ring stiffness of double-wall spiral pipes made from this material can reach 12 kN, and the pipes show no cracking even when compressed to 50%. Compared to double-wall spiral pipes made from high-density polyethylene, which only achieve a ring stiffness of 8 kN, UPET double-wall spiral pipes exhibit a significantly improved ring stiffness. This can significantly expand the application market for double-wall spiral pipes.

[0052] Example 3

[0053] This embodiment provides a method for preparing UPE-T material, specifically including the following steps:

[0054] (1) Preparation of eutectic solubilizer:

[0055] Ammonium dodecylbenzenesulfonate was dissolved in acetone and then added to a high-speed mixer containing montmorillonite for high-speed mixing. During the mixing process, the temperature was raised to 80°C. After the acetone was completely evaporated, ferric chloride was added and mixing was continued for 5 minutes, followed by cooling. The weight of ferric chloride added was 3% of the weight of montmorillonite, and the weight of ammonium dodecylbenzenesulfonate was 3% of the weight of montmorillonite.

[0056] (2) Preparation of flow modifier:

[0057] Linear low-density polyethylene with a melt index of 20 was selected as the raw material. Xylene was used as the solvent and BPO (benzoyl peroxide) was used as the initiator. Glycidyl methacrylate, butyl methacrylate, and methyl methacrylate, accounting for 30% of the weight of polyethylene, were added and grafted at 85°C for 4 hours.

[0058] (3) Preparation of UPE-T materials:

[0059] The following components were selected: ultra-high molecular weight polyethylene with an average molecular weight of 250 (20%), high-density polyethylene with a density of 0.95 (40%), PET bottle grade (30%), eutectic accelerator (5%), and flow modifier (5%).

[0060] Ultra-high molecular weight polyethylene and flow modifier were added to a high-speed mixer and mixed at 90°C for 10 minutes. After cooling, high-density polyethylene, PET and eutectic solubilizer were added and mixed at 3000 rpm for 5 minutes. Then, the mixture was melt-blended in a twin-screw extruder.

[0061] The physical properties of the prepared UPE-T material were tested, and the results are as follows.

[0062] The UPET material produced by this method has the following physical properties: melt index 0.5-0.8, tensile strength greater than 38 MPa, flexural strength greater than 40 MPa, and notched cantilever beam impact strength greater than 15 KJ / m. 2 The mechanical properties of this material are far superior to the mechanical strength and toughness of ordinary polyethylene.

[0063] The UPE-T material obtained above was used to prepare double-walled wound tubes, and the preparation method was the same as in Example 1.

[0064] The physical and mechanical properties of the prepared double-walled spiral tube were tested, and the results are as follows.

[0065] Double-wall spiral pipes made from this material exhibit a ring stiffness exceeding 12 kN, and show no cracking even under 50% compression in terms of ring flexibility. Compared to double-wall spiral pipes made from high-density polyethylene, which only achieve a ring stiffness of 8 kN, UPET double-wall spiral pipes demonstrate a significant improvement in ring stiffness. This can substantially expand the application market for double-wall spiral pipes.

[0066] Example 4

[0067] This embodiment provides a method for preparing UPE-T material, specifically including the following steps:

[0068] (1) Preparation of eutectic solubilizer:

[0069] Dissolve octadecyltrimethylammonium chloride in acetone, then add it to a high-speed mixer containing kaolin and mix at high speed. During the mixing process, the temperature is raised to 80°C. After the acetone has completely evaporated, aluminum trichloride is added and mixing continues for 5 minutes, followed by cooling. The weight of aluminum trichloride added is 3% of the weight of kaolin, and the weight of octadecyltrimethylammonium chloride is 3% of the weight of kaolin.

[0070] (2) Preparation of flow modifier: Same as in Example 3.

[0071] (3) Preparation of UPE-T materials:

[0072] The following components were selected: ultra-high molecular weight polyethylene with an average molecular weight of 250 (15%), high-density polyethylene with a density of 0.95 (50%), PET bottle grade (25%), eutectic accelerator (5%), and flow modifier (5%).

[0073] Ultra-high molecular weight polyethylene and flow modifier were added to a high-speed mixer and mixed at 90°C for 10 minutes. After cooling, high-density polyethylene, PET and eutectic solubilizer were added and mixed at 3000 rpm for 5 minutes. Then, the mixture was melt-blended in a twin-screw extruder.

[0074] The physical properties of the prepared UPE-T material were tested, and the results are as follows.

[0075] The prepared UPET material has a melt index of 1.1, a tensile strength of 34 MPa, a flexural strength of 33 MPa, and a notched cantilever beam impact strength of 16 KJ / m. 2 The mechanical properties of this material are far superior to the mechanical strength and toughness of ordinary polyethylene.

[0076] The UPE-T material obtained above was used to prepare double-walled wound tubes, and the preparation method was the same as in Example 1.

[0077] The physical and mechanical properties of the prepared double-walled spiral tube were tested, and the results are as follows.

[0078] Double-wall spiral pipes made from this material can achieve a ring stiffness of 11 kN, exhibiting no cracking at a compression ratio of 50% and demonstrating excellent ring flexibility. Compared to double-wall spiral pipes made from high-density polyethylene, which only achieve a ring stiffness of 8 kN, UPET double-wall spiral pipes show a significantly improved ring stiffness. This can significantly expand the application market for double-wall spiral pipes.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a UPE-T material, characterized in that, By weight percentage, the UPE-T material is composed of the following raw materials: 5-30% ultra-high molecular weight polyethylene, 30-70% high-density polyethylene, 10-40% PET, 2-5% eutectic solubilizer, and 3-10% flow modifier; The preparation method includes the following steps: (1) Preparation of eutectic solubilizer: The interlayer stripping agent is dissolved in a low-boiling-point solvent and then added to a high-speed mixer for high-speed mixing with mineral fillers having a layered structure. During the mixing process, the temperature is naturally raised to 80°C. After the low-boiling-point solvent evaporates, an ionic semi-interpenetrating network crosslinking agent is added and the mixture is continued for 5 minutes, followed by cooling. The ionic semi-interpenetrating network crosslinking agent is one of aluminum trichloride, zinc chloride, or ferric trichloride. (2) Preparation of flow modifier: Using linear low-density polyethylene as raw material, solvent, initiator and methacrylate monomers are added, and graft polymerization reaction is carried out at 80-90℃ for 3-5 hours. After cooling, the product is precipitated, crushed and dried. (3) Preparation of UPE-T materials: Ultra-high molecular weight polyethylene and flow modifier were added to a high-speed mixer and mixed for 10 minutes at 80℃-100℃. After cooling, high-density polyethylene, PET and eutectic solubilizer were added and mixed evenly in the high-speed mixer. The mixture was then melt-blended using a twin-screw extruder.

2. The method for preparing a UPE-T material according to claim 1, characterized in that: The ultra-high molecular weight polyethylene has an average molecular weight of 2.5 million; the high-density polyethylene has a melt index of 0.1-2 and a density of 0.94-0.95 g / cm³. 3 .

3. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (1), the weight of the interlayer stripping agent is 2-6% of the weight of the mineral filler with a layered structure; the weight of the ionic semi-interpenetrating network crosslinking agent is 3-15% of the weight of the mineral filler with a layered structure.

4. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (1), the interlayer stripping agent is one of long-chain alkylammonium quaternary ammonium salt or long-chain alkyl sulfonate; the low-boiling point solvent is one of acetone or chloroform; and the layered mineral filler is one of montmorillonite or kaolinite.

5. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (2), the melt index of the linear low-density polyethylene is 20-50.

6. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (2), the solvent is xylene; the initiator is benzoyl peroxide.

7. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (2), the methacrylate monomer is any one or more of octadecyl methacrylate, glycidyl methacrylate, butyl methacrylate, and methyl methacrylate.

8. The method for preparing a UPE-T material according to claim 1, characterized in that: In step (3), the temperatures of each section of the twin-screw extruder are as follows: feeding section temperature 160-180℃, mixing section temperature 230-260℃, and metering section temperature 220-250℃.

9. The application of the UPE-T material prepared by the preparation method according to any one of claims 1-8, characterized in that: The UPE-T material is used in the production of double-wall spiral pipes.