UPE-T material and preparation method and application thereof

Abstract

The invention discloses a UPE-T material as well as a preparation method and application thereof, and belongs to the technical field of polymer composite materials. The material is prepared from the following raw materials in percentage by mass: 5-30% of ultra-high molecular weight polyethylene, 30-70% of high-density polyethylene, 10-40% of PET, 2-5% of eutectic solubilizer and 3-10% of flow modifier. Montmorillonite or kaolin is used as a basis, and an interlayer stripping agent and an ionic semi-interpenetrating network cross-linking agent are added to modify the montmorillonite or kaolin to prepare the eutectic solubilizer; the preparation method comprises the following steps: by taking linear low-density polyethylene as a raw material, xylene as a solvent and BPO as an initiator, adding a methacrylate monomer to carry out graft polymerization reaction to prepare a flow modifier; the ultra-high molecular weight polyethylene and the flow modifier are mixed and cooled, then the high-density polyethylene, the PET and the eutectic solubilizer are added and mixed uniformly in a high-speed mixer, and a twin-screw extruder is adopted for melt blending. The prepared UPE-T material is applied to production of the double-wall winding pipe, and the prepared double-wall winding pipe has good ring stiffness and ring flexibility.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer composite materials, and in particular to a UPE-T material and a preparation method and application thereof. Background Art

[0002] Double-walled spiral pipes are composed of two layers, the inner layer is responsible for the main fluid transmission, while the outer layer provides additional mechanical strength and protection from environmental factors. Compared with traditional single-layer pipes, double-walled pipes have become a common form of municipal pipes with their unique structural design.

[0003] Ring stiffness and ring flexibility are the most important performance indicators of pipelines, because in the application of buried drainage pipes, the pipeline does not bear internal pressure or the pressure is very low, but only bears external pressure load (including dynamic load and static load). If the ring stiffness of the pipeline is too small, the pipeline will be greatly deformed and damaged, so the safe use of the pipeline cannot be guaranteed; if the ring flexibility is too low, the pipeline is easy to be damaged and leak during use.

[0004] The common raw materials for existing double-walled winding pipes are polyethylene and polypropylene. The pipes made from them usually have the advantages of good flexibility and low cost, but their strength and ring stiffness are low, which limits their use in certain special occasions. In order to improve the rigidity and strength of the material, polyethylene or polypropylene is modified using ultra-high molecular weight polyethylene and PET materials to improve the rigidity of the material without significantly increasing the cost, thereby improving the rigidity of the pipe. PET has the advantages of high specific strength, aging resistance, and low price, but due to its different structural morphology from polyethylene and polypropylene, it has certain limitations in compatibility; ultra-high molecular weight polyethylene has good impact resistance, strength, and excellent high and low temperature resistance, which can improve the comprehensive performance of polyethylene or polypropylene. However, the processing flow of ultra-high molecular weight polyethylene is too poor, and it is difficult to achieve a good blending effect with polyethylene or polypropylene through general processing methods. Good flow modification must be adopted to achieve good mixing with polyethylene or polypropylene.

[0005] In view of the above problems, the present invention provides a UPE-T material and a preparation method and application thereof. Summary of the invention

[0006] The purpose of the present invention is to provide a UPE-T material and a preparation method and application thereof, and to apply the prepared UPE-T material to the production of double-walled wound pipes to solve the problem of low ring stiffness of existing double-walled wound pipes mentioned in the above background technology, so that the prepared double-walled wound pipes have better ring stiffness and good ring flexibility.

[0007] To achieve the above object, the present invention provides a UPE-T material, which is composed of the following raw materials by mass percentage: 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] The present 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 exfoliating agent is dissolved in a low boiling point solvent, and then added into a high-speed mixer and mixed with a mineral filler having a layered structure at a high speed. 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 mixed for 5 minutes, and then cooled;

[0012] (2) Preparation of flow modifier:

[0013] Take linear low-density polyethylene as raw material, add solvent, initiator and methacrylate monomer, carry out graft polymerization reaction at 80-90°C for 3-5 hours, cool, precipitate the product, crush and dry;

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

[0015] Add ultra-high molecular weight polyethylene and flow modifier into a high-speed mixer, mix at 80°C-100°C for 10 minutes, add high-density polyethylene, PET and eutectic solubilizer into the high-speed mixer after cooling, mix evenly, and use a twin-screw extruder for melt blending.

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

[0017] Preferably, in step (1), the interlayer stripping agent is one of long-chain alkyl ammonium quaternary ammonium salts or long-chain alkyl sulfonates; the low boiling point solvent is one of acetone or chloroform; the mineral filler with a layered structure is one of montmorillonite or kaolin; and the ionic semi-interpenetrating network crosslinking agent is one of aluminum chloride, 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 temperature of each section of the twin-screw extruder is: the temperature of the feeding section is 160-180°C, the temperature of the mixing section is 230-260°C, and the temperature of the metering section is 220-250°C.

[0022] The present invention also provides application of the above-mentioned UPE-T material in the production of double-wall winding pipes.

[0023] Polyethylene and polyester (PET) are both crystalline polymer materials, but polyethylene or polypropylene is a non-polar polymer material, while PET is a polar polymer material. The compatibility between the two is poor and it is difficult to effectively blend. Ultra-high molecular weight polyethylene has the advantages of high strength and high rigidity, but it is difficult to achieve thermoplastic processing under general processing conditions. Using polyethylene grafted with acrylate can not only reduce its processing viscosity, but also serve as the compatibility between polyethylene, polypropylene and polyester (PET). Kaolin and montmorillonite are flaky materials and are crystallization nucleating agents for polyethylene, polypropylene and polyester. Adding a crystallization nucleating agent that has undergone interlayer exfoliation to the blending system can promote the formation of eutectics between polyolefins and polyesters, thereby achieving good compatibility between the two. Improve the physical and mechanical properties of the blending system. At the same time, adding aluminum chloride or ferric chloride, its metal ions can form a semi-interpenetrating network with the carbonyl groups in polyester and acrylate through electrostatic interaction, further improving the stability of the blending system.

[0024] Therefore, the present invention provides a UPE-T material and a preparation method and application thereof. The prepared UPE-T material has good mechanical strength and is used to produce double-walled winding pipes with high ring stiffness and good rigidity and flexibility.

[0025] The technical solution of the present invention is further described in detail below through embodiments. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Any other changes, modifications, substitutions, combinations, simplifications made without violating the spirit and principle of the present invention should all be equivalent replacement methods and are included in the protection scope of the present invention. In addition, it should be understood that after reading the content of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application, and all belong to the scope of protection of the present invention.

[0027] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0028] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0029] Unless otherwise specified in the present invention, the reagents, instruments, and equipment used are those commonly used by technicians in this field.

[0030] Example 1

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

[0032] (1) Preparation of eutectic solubilizer:

[0033] Dissolve octadecyltrimethylammonium chloride in acetone, then add it into a high-speed mixer filled with kaolin for high-speed mixing, heat it to 80°C during mixing, add aluminum chloride and continue mixing for 5 minutes after the acetone is completely volatilized, and cool it; wherein the weight of the added aluminum chloride is 3% of the weight of the kaolin, and the weight of the octadecyltrimethylammonium chloride is 2% of the weight of the 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, BPO (benzoyl peroxide) was used as the initiator, 30% of the weight of polyethylene glycidyl methacrylate, 15% of butyl methacrylate and 15% of methyl methacrylate were added, and the grafting polymerization reaction was carried out at 85°C for 4 hours.

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

[0037] Take ultra-high molecular weight polyethylene with an average molecular weight of 250 (accounting for 25%), high-density polyethylene with a density of 0.95 (accounting for 40%), PET bottle grade (accounting for 25%), eutectic promoter (accounting for 5%) and flow modifier (accounting for 5%);

[0038] The 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, mixed at a speed of 3000 rpm for five minutes, and then melt-blended in a twin-screw extruder.

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

[0040] The prepared material has the following physical properties: melt index 0.2-0.5, tensile strength greater than 35Mpa; bending strength greater than 40Mpa. Izod notch impact strength greater than 20KJ / m 2 .

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

[0042] The UPE-T material prepared above is used to prepare double-wall winding pipes. The preparation method is as follows: the UPET material is made into a round tube or a square tube according to the wall thickness requirements through a twin-screw extruder, and then stretched and wound on a winding machine, and then bonded to make double-wall winding pipes of various diameters. The extruder temperature is controlled at 250°C. Before winding, the pipe temperature is controlled at 70°C.

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

[0044] The ring stiffness of the double-walled winding pipe made of this material is greater than 12KN, and it also has excellent ring flexibility, and will not crack when the compression deformation exceeds 50%. Compared with the ring stiffness of the double-walled winding pipe made of high-density polyethylene, which can only reach 8KN, the ring stiffness of the UPET double-walled winding pipe has been greatly improved, which can significantly expand the application market space of the double-walled winding pipe.

[0045] Example 2

[0046] This embodiment provides a method for preparing a UPE-T material. The method for preparing a eutectic solubilizer and a flow modifier is the same as that in Example 1, and the amount added is also the same as that in Example 1. The only difference from Example 1 is that 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 promoter (accounting for 5%) and flow modifier (accounting for 5%) are selected.

[0047] The physical properties of the prepared UPE-T material were tested, and the test 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 36Mpa, bending strength greater than 35MPa, cantilever beam notch impact strength greater than 18KJ / m 2 The mechanical properties of this material are much higher than the mechanical strength and toughness of ordinary polyethylene.

[0049] The UPE-T material prepared above is used to prepare a double-walled winding pipe, and the preparation method is the same as Example 1.

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

[0051] The ring stiffness of the double-walled winding pipe made of this material can reach 12KN, and the ring flexibility does not crack when the pipe is compressed to 50%. Compared with the ring stiffness of the double-walled winding pipe made of high-density polyethylene, which can only reach 8KN, the ring stiffness of the UPET double-walled winding pipe has been greatly improved. It can significantly expand the application market space of double-walled winding pipes.

[0052] Example 3

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

[0054] (1) Preparation of eutectic solubilizer:

[0055] Ammonium dodecylbenzene sulfonate is dissolved in acetone, and then added into a high-speed mixer filled with montmorillonite for high-speed mixing. During the mixing process, the temperature is raised to 80° C. After the acetone is completely volatilized, ferric chloride is added and the mixing is continued for 5 minutes, and the mixture is cooled. The weight of the added ferric chloride is 3% of the weight of the montmorillonite, and the weight of the ammonium dodecylbenzene sulfonate is 3% of the weight of the 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, BPO (benzoyl peroxide) was used as the initiator, 30% of the weight of polyethylene glycidyl methacrylate, 10% of butyl methacrylate and 10% of methyl methacrylate were added, and the grafting polymerization reaction was carried out at 85°C for 4 hours.

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

[0059] Take 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 40%), PET bottle grade (accounting for 30%), eutectic promoter (accounting for 5%) and flow modifier (accounting for 5%);

[0060] The 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, mixed at a speed of 3000 rpm for five minutes, and then melt-blended in a twin-screw extruder.

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

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

[0063] The UPE-T material prepared above is used to prepare a double-walled winding pipe, and the preparation method is the same as Example 1.

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

[0065] The ring stiffness of the double-walled winding pipe made of this material is higher than 12KN, and the ring flexibility does not crack when the pipe is compressed to 50%. Compared with the ring stiffness of the double-walled winding pipe made of high-density polyethylene, which can only reach 8KN, the ring stiffness of the UPET double-walled winding pipe has been greatly improved. It can significantly expand the application market space of double-walled winding pipes.

[0066] Example 4

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

[0068] (1) Preparation of eutectic solubilizer:

[0069] Dissolve octadecyltrimethylammonium chloride in acetone, then add it into a high-speed mixer filled with kaolin for high-speed mixing, heat it to 80°C during mixing, add aluminum chloride and continue mixing for 5 minutes after the acetone is completely volatilized, and cool it; wherein the weight of the added aluminum chloride is 3% of the weight of the kaolin, and the weight of the octadecyltrimethylammonium chloride is 3% of the weight of the kaolin.

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

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

[0072] Take ultra-high molecular weight polyethylene with an average molecular weight of 250 (accounting for 15%), high-density polyethylene with a density of 0.95 (accounting for 50%), PET bottle grade (accounting for 25%), eutectic promoter (accounting for 5%) and flow modifier (accounting for 5%);

[0073] The 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, mixed at a speed of 3000 rpm for five minutes, and then melt-blended in a twin-screw extruder.

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

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

[0076] The UPE-T material prepared above is used to prepare a double-walled winding pipe, and the preparation method is the same as Example 1.

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

[0078] The ring stiffness of the double-walled winding pipe made of this material can reach 11KN. When the compression ratio is 50%, there is no cracking and it has good ring flexibility. Compared with the ring stiffness of the double-walled winding pipe made of high-density polyethylene, which can only reach 8KN, the ring stiffness of the UPET double-walled winding pipe has been greatly improved. It can significantly expand the application market space of double-walled winding pipes.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A UPE-T material, characterized in that: The invention is composed of the following raw materials by mass percentage: 5-30% of ultra-high molecular weight polyethylene, 30-70% of high-density polyethylene, 10-40% of PET, 2-5% of eutectic solubilizer and 3-10% of flow modifier.

2. A UPE-T material according to claim 1, characterized in that: 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.

3. A method for preparing a UPE-T material according to any one of claims 1 to 2, characterized in that: The following steps are involved: (1) Preparation of eutectic solubilizer: The interlayer exfoliating agent is dissolved in a low boiling point solvent, and then added into a high-speed mixer and mixed with a mineral filler having a layered structure at a high speed. 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 mixed for 5 minutes, and then cooled; (2) Preparation of flow modifier: Take linear low-density polyethylene as raw material, add solvent, initiator and methacrylate monomer, carry out graft polymerization reaction at 80-90°C for 3-5 hours, cool, precipitate the product, crush and dry; (3) Preparation of UPE-T materials: Add ultra-high molecular weight polyethylene and flow modifier into a high-speed mixer, mix at 80°C-100°C for 10 minutes, add high-density polyethylene, PET and eutectic solubilizer into the high-speed mixer after cooling, mix evenly, and use a twin-screw extruder for melt blending.

4. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (1), the interlayer exfoliating 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.

5. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (1), the interlayer stripping agent is one of long-chain alkyl ammonium quaternary ammonium salts or long-chain alkyl sulfonates; the low boiling point solvent is one of acetone or chloroform; the mineral filler with a layered structure is one of montmorillonite or kaolin; and the ionic semi-interpenetrating network crosslinking agent is one of aluminum chloride, zinc chloride or ferric chloride.

6. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (2), the melt index of the linear low-density polyethylene is 20-50.

7. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (2), the solvent is xylene; and the initiator is benzoyl peroxide.

8. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (2), the methacrylate monomer is any one or more of octadecyl methacrylate, glycidyl methacrylate, butyl methacrylate, and methyl methacrylate.

9. The method for preparing a UPE-T material according to claim 3, characterized in that: In step (3), the temperature of each section of the twin-screw extruder is: the temperature of the feeding section is 160-180°C, the temperature of the mixing section is 230-260°C, and the temperature of the metering section is 220-250°C.

10. The use of a UPE-T material according to any one of claims 1 to 2, characterized in that: The UPE-T material is used for the production of double-walled spiral wound pipes.