High-strength anti-aging radiation crosslinked polyethylene pipe and preparation method thereof

Abstract

The invention relates to a high-strength anti-aging radiation crosslinking polyethylene pipe and a preparation method thereof, and belongs to the technical field of polyethylene pipes. The preparation method comprises the following steps: creatively taking a 2, 4-dihydroxybenzophenone ultraviolet light absorber as a modification basis, firstly modifying hydroxyl at a site 4 by using chloroacetyl chloride, carrying out deacidification substitution on the hydroxyl and acyl chloride, then adding ethidene diamine as a modifier of amino, finishing modification of the amino based on the action of a C-Cl bond and the amino, and finally preparing the modified amino. Finally, glycidyl methacrylate is added for ring-opening bonding of epoxy groups to form a compound containing terminal double bonds, so that the anti-aging cross-linking agent is prepared, the anti-aging cross-linking agent, polyethylene resin and a lubricant are sequentially subjected to mixing, extrusion pipe forming and irradiation operation, and the radiation cross-linked polyethylene pipe is obtained. And moreover, the anti-aging performance is excellent, and the market application prospect is very good.

Description

Technical Field

[0001] The invention belongs to the technical field of polyethylene pipes, and in particular relates to a high-strength aging-resistant radiation cross-linked polyethylene pipe and a preparation method thereof. Background Art

[0002] As a resin with a linear polymer structure, polyethylene is widely used in the field of pipes due to its many advantages such as corrosion resistance and light weight. Among them, a large number of studies have shown that most of the properties of cross-linked polyethylene (i.e., forming a network structure) will be improved to varying degrees. If classified according to the cross-linking method, cross-linked polyethylene can be roughly divided into peroxide cross-linked polyethylene, silane cross-linked polyethylene and radiation cross-linked polyethylene. Compared with the first two cross-linking methods, radiation cross-linked polyethylene has the characteristics of high production efficiency, convenient production, and no need for additional initiators. The pipes produced by this method have higher chemical purity, which broadens the scope of application. Scope of use, however, the existing radiation cross-linked polyethylene still has certain disadvantages that limit its actual application effect. This is because, on the one hand, radiation cross-linked polyethylene is essentially still based on polyethylene as the basic raw material, without the introduction of any reinforcing substances. Although the strength is improved after cross-linking, there is still room for improvement. On the other hand, based on the disadvantage of polyethylene's easy aging, most of the existing radiation cross-linked polyethylene is added with anti-aging agents. However, these anti-aging agents are basically small molecular substances, which are very easy to migrate and precipitate under the influence of heat, external forces and other factors, which not only causes waste, but also pollutes the environment or the materials transported by the pipes. Summary of the invention

[0003] In view of the problems existing in the prior art, the purpose of the present invention is to provide a high-strength aging-resistant radiation cross-linked polyethylene pipe and a preparation method thereof. The present invention creatively uses 2,4-dihydroxybenzophenone ultraviolet absorber as a modification basis, firstly modifies the hydroxyl group at position 4 with chloroacetyl chloride, and deacidification substitution of the hydroxyl group and the acyl chloride occurs, then adds ethylenediamine as an amino modifier, and completes the modification of the amino group based on the action of the C-Cl bond and the amino group, and finally adds glycidyl methacrylate for ring-opening bonding of the epoxy group to form a compound containing a terminal double bond, thereby preparing an aging-resistant cross-linking agent, and mixing it with a polyethylene resin and a lubricant in sequence, extruding it into a pipe, and irradiating it to obtain a radiation cross-linked polyethylene pipe, which not only has high strength but also has excellent aging resistance and has a very good market application prospect.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A high-strength aging-resistant radiation cross-linked polyethylene pipe is prepared from polyethylene resin, lubricant and aging-resistant cross-linking agent.

[0006] As a preferred technical solution of the present invention, the mass ratio of the polyethylene resin, the lubricant and the anti-aging cross-linking agent is 98:0.8-1:2-3.

[0007] As a preferred technical solution of the present invention, the polyethylene resin comprises the following components in weight percentage: 70-100wt% of high-density polyethylene and 0-30wt% of linear low-density polyethylene.

[0008] As a preferred technical solution of the present invention, the lubricant is a stearate lubricant.

[0009] As a preferred technical solution of the present invention, the anti-aging crosslinking agent is prepared by the following steps:

[0010] Step A: adding 25-30 parts by weight of chloroacetyl chloride to 150 parts by weight of dichloromethane, and then dropping 100-120 parts by weight of 2,4-dihydroxybenzophenone solution while stirring in an ice bath, and continuing to stir for 4-6 hours at room temperature after the dropwise addition, and purifying to obtain component A; the 2,4-dihydroxybenzophenone solution refers to a mixture of 2,4-dihydroxybenzophenone, triethylamine and dichloromethane in a mass ratio of 3:2.5:10-12, stirred at room temperature for 15-30 minutes to obtain a mixture;

[0011] Step B: Add 10 parts by weight of component A and 6-8 parts by weight of triethylamine to 100 parts by weight of dichloromethane, then dropwise add 18-20 parts by weight of ethylenediamine at room temperature while stirring, continue stirring for 2-4 hours after the addition is complete, and purify to obtain component B;

[0012] Step C: Add 6 parts by weight of component B and 0.5-1 parts by weight of glycidyl methacrylate to 100 parts by weight of dichloromethane, then stir and mix for 10-12 hours at room temperature in the dark, and purify to complete the preparation.

[0013] Furthermore, the dripping rate in step A is controlled at 1-2 drops / s.

[0014] Furthermore, the purification in step A refers to adding 300 parts by weight of deionized water, shaking, standing for 5-10 minutes to separate the layers, removing the lower layer, and then distilling and concentrating at 45-50°C to 8-10% of the original volume to obtain a first component, adding an equal volume of methanol to the first component, stirring for 5-10 minutes to mix, then distilling and concentrating at 45-50°C to 45-50% of the original volume, naturally cooling to room temperature, standing for 5-10 minutes, filtering, removing the filtrate, re-adding 30 parts by weight of dichloromethane and 400-500 parts by weight of petroleum ether, stirring for 20-30 minutes to mix, filtering, taking the filter residue, and finally vacuum drying at 40-60°C until constant weight.

[0015] Furthermore, the dripping rate in step B is controlled at 1-2 drops / s.

[0016] Furthermore, the purification in step B refers to adding 200 parts by weight of deionized water, shaking, standing for 5-10 minutes to separate the layers, taking the lower layer, and then distilling at 45-50° C. until the volatiles are completely removed.

[0017] Furthermore, the purification in step C refers to distillation at 40° C. until the volatiles are completely removed.

[0018] A method for preparing a high-strength, aging-resistant, radiation-cross-linked polyethylene pipe, the method comprising the following steps:

[0019] The polyethylene resin, lubricant and anti-aging cross-linking agent are added into a mixer for mixing, and then extruded into a tube by a tube extruder, and finally irradiated by an electron accelerator to complete the preparation.

[0020] As a preferred technical solution of the present invention, the working parameters of the mixer are as follows: the stirring speed is controlled at 750-1500 r / min, the time is controlled at 5-10 min, and the temperature is controlled at 20-40°C.

[0021] As a preferred technical solution of the present invention, the working parameters of the tube extruder are as follows: the temperature is controlled at 160-165°C, and the extrusion speed is controlled at 15-30m / min.

[0022] As a preferred technical solution of the present invention, the irradiation dose is 100-125K Gy.

[0023] Beneficial effects of the present invention:

[0024] (1) The present invention creatively uses 2,4-dihydroxybenzophenone ultraviolet absorber as a modification basis, firstly modifies the hydroxyl group at position 4 thereof with chloroacetyl chloride, and causes deacidification substitution of the hydroxyl group and the acyl chloride, then adds ethylenediamine as an amino modifier, and completes the modification of the amino group based on the action of the C-Cl bond and the amino group, and finally adds glycidyl methacrylate to perform ring-opening bonding of the epoxy group to form a compound containing a terminal double bond, thereby preparing an aging-resistant crosslinking agent, which is then mixed with a polyethylene resin and a lubricant, extruded into a tube, and irradiated to obtain a radiation-crosslinked polyethylene pipe, which not only has high strength but also has excellent aging resistance and has a very good market application prospect.

[0025] (2) The present invention creatively prepares an anti-aging crosslinking agent from 2,4-dihydroxybenzophenone ultraviolet absorber, which gives the radiation cross-linked polyethylene pipe obtained better strength and anti-aging performance. On the one hand, the anti-aging crosslinking agent still retains the ultraviolet absorption functional group (hydroxyl group at position 2) in 2,4-dihydroxybenzophenone, so that it can play a role in delaying aging. On the other hand, because the anti-aging crosslinking agent also contains a certain amount of terminal double bonds and has high activity, it can participate in the crosslinking of polyethylene in the subsequent irradiation process and play a "bridging" and "positioning" effect, which not only greatly promotes the crosslinking degree and correspondingly obtains higher strength, but also solves the problems of migration and precipitation.

[0026] (3) The present invention creatively uses 2,4-dihydroxybenzophenone ultraviolet absorber as the modification basis, and gradually modifies it to prepare an anti-aging crosslinking agent. The hydroxyl group at position 2 in the molecular structure of 2,4-dihydroxybenzophenone is a UV absorbing functional group. Since it forms an intramolecular hydrogen bond with the ketone carbonyl group, the reaction activity is reduced, while the activity of the hydroxyl group at position 4 is relatively high, so it can provide a basis for modification. At the same time, during the modification process, the amount of glycidyl methacrylate has a great influence on the performance of the radiation cross-linked polyethylene pipe finally obtained. When the amount is too little, the migration and precipitation problems cannot be solved well. When the amount is too much, the terminal double bond content is high, resulting in "excess", which cannot form an effective network structure with the polyethylene matrix, resulting in a certain decrease in strength. DETAILED DESCRIPTION

[0027] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0028] The high density polyethylene in all the embodiments and comparative examples of the present invention was measured, and the MFR 190℃ / 2.16kg 0.5g / 10min; Linear low density polyethylene is measured, MFR190℃ / 2.16kg 1g / 10min; stearate lubricants are all magnesium stearate.

[0029] Example 1

[0030] A high-strength aging-resistant radiation cross-linked polyethylene pipe is prepared from polyethylene resin, lubricant and aging-resistant cross-linking agent.

[0031] The mass ratio of the polyethylene resin, the lubricant and the anti-aging cross-linking agent is 98:0.8:2.

[0032] The polyethylene resin comprises the following components in weight percentage: 70 wt % of high-density polyethylene and 30 wt % of linear low-density polyethylene.

[0033] The lubricant is a stearate lubricant.

[0034] The anti-aging crosslinking agent is prepared by the following steps:

[0035] Step A: adding 25 parts by weight of chloroacetyl chloride to 150 parts by weight of dichloromethane, and then dropping 100 parts by weight of 2,4-dihydroxybenzophenone solution while stirring in an ice bath, and after the dropwise addition is completed, stirring and mixing at room temperature for 4 hours, purifying, and obtaining component A; the 2,4-dihydroxybenzophenone solution refers to a mixture of 2,4-dihydroxybenzophenone, triethylamine and dichloromethane in a mass ratio of 3:2.5:10, stirred at room temperature for 15 minutes;

[0036] Step B: Add 10 parts by weight of component A and 6 parts by weight of triethylamine to 100 parts by weight of dichloromethane, then dropwise add 18 parts by weight of ethylenediamine at room temperature while stirring, continue stirring for 2 hours after the addition is complete, and purify to obtain component B;

[0037] Step C: Add 6 parts by weight of component B and 0.5 parts by weight of glycidyl methacrylate to 100 parts by weight of dichloromethane, and then stir and mix for 10 hours at room temperature in the dark, and purify to complete the preparation.

[0038] The rate of dripping in step A is controlled at 1 drop / s.

[0039] The purification in step A refers to adding 300 parts by weight of deionized water, shaking, standing for 5 minutes to separate the layers, removing the lower layer, and then distilling and concentrating to 8% of the original volume at 45°C to obtain a first component, adding methanol of an equal volume to the first component, stirring for 5 minutes to mix, then distilling and concentrating to 45% of the original volume at 45°C, naturally cooling to room temperature, standing for 5 minutes, filtering, removing the filtrate, re-adding 30 parts by weight of dichloromethane and 400 parts by weight of petroleum ether, stirring for 20 minutes to mix, filtering, taking the filter residue, and finally vacuum drying at 40°C until constant weight.

[0040] The dripping rate in step B is controlled at 1 drop / s.

[0041] The purification in step B refers to adding 200 parts by weight of deionized water, shaking, standing for 5 minutes to separate the layers, taking the lower layer, and then distilling at 45° C. until the volatiles are completely removed.

[0042] The purification in step C refers to distillation at 40° C. until the volatiles are completely removed.

[0043] A method for preparing a high-strength, aging-resistant, radiation-cross-linked polyethylene pipe, the method comprising the following steps:

[0044] The polyethylene resin, lubricant and anti-aging cross-linking agent are added into a mixer for mixing, and then extruded into a tube by a tube extruder, and finally irradiated by an electron accelerator to complete the preparation.

[0045] The working parameters of the mixer are as follows: the stirring speed is controlled at 750 r / min, the stirring time is controlled at 5 min, and the temperature is controlled at 20°C.

[0046] The working parameters of the tube extruder are as follows: the temperature is controlled at 160° C. and the extrusion speed is controlled at 15 m / min.

[0047] The irradiation dose of the irradiation is 100 KGy.

[0048] Example 2

[0049] A high-strength aging-resistant radiation cross-linked polyethylene pipe is prepared from polyethylene resin, lubricant and aging-resistant cross-linking agent.

[0050] The mass ratio of the polyethylene resin, the lubricant and the anti-aging cross-linking agent is 98:1:3.

[0051] The polyethylene resin comprises the following components in weight percentage: 90 wt % of high-density polyethylene and 10 wt % of linear low-density polyethylene.

[0052] The lubricant is a stearate lubricant.

[0053] The anti-aging crosslinking agent is prepared by the following steps:

[0054] Step A: adding 30 parts by weight of chloroacetyl chloride to 150 parts by weight of dichloromethane, and then dropping 120 parts by weight of 2,4-dihydroxybenzophenone solution while stirring in an ice bath, and continuing to stir and mix at room temperature for 6 hours after the dropwise addition is completed, and purifying to obtain component A; the 2,4-dihydroxybenzophenone solution refers to a mixture of 2,4-dihydroxybenzophenone, triethylamine and dichloromethane in a mass ratio of 3:2.5:12 at room temperature after stirring for 30 minutes;

[0055] Step B: Add 10 parts by weight of component A and 8 parts by weight of triethylamine to 100 parts by weight of dichloromethane, then dropwise add 20 parts by weight of ethylenediamine at room temperature while stirring, continue stirring for 4 hours after the addition is complete, and purify to obtain component B;

[0056] Step C: Add 6 parts by weight of component B and 1 part by weight of glycidyl methacrylate to 100 parts by weight of dichloromethane, and then stir and mix for 12 hours at room temperature in the dark, and purify to complete the preparation.

[0057] The dripping rate in step A is controlled at 2 drops / s.

[0058] The purification in step A refers to adding 300 parts by weight of deionized water, shaking, standing for 10 minutes to separate layers, removing the lower layer, and then distilling and concentrating to 10% of the original volume at 50°C to obtain a first component, adding methanol of an equal volume to the first component, stirring for 10 minutes to mix, then distilling and concentrating to 50% of the original volume at 50°C, naturally cooling to room temperature, standing for 10 minutes, filtering, removing the filtrate, re-adding 30 parts by weight of dichloromethane and 500 parts by weight of petroleum ether, stirring for 30 minutes to mix, filtering, taking the filter residue, and finally vacuum drying at 60°C until constant weight.

[0059] The dropping rate in step B is controlled at 2 drops / s.

[0060] The purification in step B refers to adding 200 parts by weight of deionized water, shaking, standing for 10 minutes to separate the layers, taking the lower layer, and then distilling at 50° C. until the volatiles are completely removed.

[0061] The purification in step C refers to distillation at 40° C. until the volatiles are completely removed.

[0062] A method for preparing a high-strength, aging-resistant, radiation-cross-linked polyethylene pipe, the method comprising the following steps:

[0063] The polyethylene resin, lubricant and anti-aging cross-linking agent are added into a mixer for mixing, and then extruded into a tube by a tube extruder, and finally irradiated by an electron accelerator to complete the preparation.

[0064] The working parameters of the mixer are as follows: the stirring speed is controlled at 1500 r / min, the time is controlled at 10 min, and the temperature is controlled at 40°C.

[0065] The working parameters of the tube extruder are as follows: the temperature is controlled at 165° C. and the extrusion speed is controlled at 30 m / min.

[0066] The irradiation dose of the irradiation is 125 KGy.

[0067] Example 3

[0068] A high-strength aging-resistant radiation cross-linked polyethylene pipe is prepared from polyethylene resin, lubricant and aging-resistant cross-linking agent.

[0069] The mass ratio of the polyethylene resin, the lubricant and the anti-aging cross-linking agent is 98:0.9:2.5.

[0070] The polyethylene resin comprises the following components in weight percentage: 80 wt % of high-density polyethylene and 20 wt % of linear low-density polyethylene.

[0071] The lubricant is a stearate lubricant.

[0072] The anti-aging crosslinking agent is prepared by the following steps:

[0073] Step A: adding 28 parts by weight of chloroacetyl chloride to 150 parts by weight of dichloromethane, and then dropping 110 parts by weight of 2,4-dihydroxybenzophenone solution while stirring in an ice bath, and continuing to stir and mix at room temperature for 5 hours after the dropwise addition is completed, and purifying to obtain component A; the 2,4-dihydroxybenzophenone solution refers to a mixture of 2,4-dihydroxybenzophenone, triethylamine and dichloromethane in a mass ratio of 3:2.5:11 at room temperature after stirring for 20 minutes;

[0074] Step B: Add 10 parts by weight of component A and 7 parts by weight of triethylamine to 100 parts by weight of dichloromethane, then dropwise add 19 parts by weight of ethylenediamine at room temperature while stirring, continue stirring for 3 hours after the addition is complete, and purify to obtain component B;

[0075] Step C: Add 6 parts by weight of component B and 0.8 parts by weight of glycidyl methacrylate to 100 parts by weight of dichloromethane, and then stir and mix for 11 hours at room temperature in the dark, and purify to complete the preparation.

[0076] The rate of the dripping in step A is controlled at 1.5 drops / s.

[0077] The purification in step A refers to adding 300 parts by weight of deionized water, shaking, standing for 8 minutes to separate the layers, removing the lower layer, and then distilling and concentrating at 48°C to 9% of the original volume to obtain a first component, adding an equal volume of methanol to the first component, stirring for 8 minutes to mix, then distilling and concentrating at 48°C to 47% of the original volume, naturally cooling to room temperature, standing for 8 minutes, filtering, removing the filtrate, re-adding 30 parts by weight of dichloromethane and 450 parts by weight of petroleum ether, stirring for 25 minutes to mix, filtering, taking the filter residue, and finally vacuum drying at 50°C until constant weight.

[0078] The dropping rate in step B is controlled at 1.5 drops / s.

[0079] The purification in step B refers to adding 200 parts by weight of deionized water, shaking, standing for 8 minutes to separate the layers, taking the lower layer, and then distilling at 49° C. until the volatiles are completely removed.

[0080] The purification in step C refers to distillation at 40° C. until the volatiles are completely removed.

[0081] A method for preparing a high-strength, aging-resistant radiation-cross-linked polyethylene pipe, the method comprising the following steps:

[0082] The polyethylene resin, lubricant and anti-aging cross-linking agent are added into a mixer for mixing, and then extruded into a tube by a tube extruder, and finally irradiated by an electron accelerator to complete the preparation.

[0083] The working parameters of the mixer are as follows: the stirring speed is controlled at 1000 r / min, the time is controlled at 8 min, and the temperature is controlled at 30°C.

[0084] The working parameters of the tube extruder are as follows: the temperature is controlled at 163° C. and the extrusion speed is controlled at 20 m / min.

[0085] The irradiation dose of the irradiation is 110 KGy.

[0086] Comparative Example 1

[0087] On the basis of Example 3, the aging-resistant crosslinking agent was changed to 2,4-dihydroxybenzophenone in an equal weight, and the rest remained unchanged.

[0088] Comparative Example 2

[0089] On the basis of Example 3, 0.8 parts by weight of glycidyl methacrylate in step C was changed to 0.4 parts by weight of glycidyl methacrylate, and the rest remained unchanged.

[0090] Comparative Example 3

[0091] On the basis of Example 3, 0.8 parts by weight of glycidyl methacrylate in step C was changed to 1.2 parts by weight of glycidyl methacrylate, and the rest remained unchanged.

[0092] Test Example 1

[0093] Performance Testing:

[0094] Mechanical properties test: The high-strength aging-resistant radiation cross-linked polyethylene pipes prepared in Example 3 and Comparative Examples 1-3 were subjected to a hydrostatic pressure resistance test (test parameters: hydrostatic pressure stress 4.4 MPa, temperature 95°C, time 1200 h) with reference to standards GB / T 18992.2-2003 and GB / T 6111-2003 to determine whether they met the requirements of no leakage and no rupture, thereby illustrating the strength.

[0095] Aging resistance test: The high-strength aging-resistant radiation cross-linked polyethylene pipes prepared in Example 3 and Comparative Examples 1-3 were irradiated with an ultraviolet lamp (365 nm) for 500 h, and then the above mechanical property test was repeated.

[0096] Anti-migration and precipitation test: The high-strength aging-resistant radiation cross-linked polyethylene pipes prepared in Example 3 and Comparative Examples 1-3 were first heat-treated at 50°C for 14 days, then washed with deionized water, naturally dried to constant weight, and then irradiated with an ultraviolet lamp (365nm) for 500h, and finally the above-mentioned mechanical properties test was repeated.

[0097] Table 1. Performance test results

[0098]

[0099]

[0100] From the comparison between Example 3 and Comparative Examples 1-3 in Test Example 1, it can be seen that the radiation cross-linked polyethylene pipe prepared by the present invention not only has high strength but also has excellent aging resistance, and effectively solves the problems of migration and precipitation.

[0101] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-strength, aging-resistant, radiation-cross-linked polyethylene pipe, characterized in that: The high-strength aging-resistant radiation cross-linked polyethylene pipe is prepared from polyethylene resin, lubricant and aging-resistant cross-linking agent.

2. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 1, characterized in that: The mass ratio of the polyethylene resin, the lubricant and the anti-aging cross-linking agent is 98:0.8-1:2-3.

3. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 1, characterized in that: The polyethylene resin comprises the following components in weight percentage: 70-100 wt % of high-density polyethylene and 0-30 wt % of linear low-density polyethylene.

4. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 1, characterized in that: The lubricant is a stearate lubricant.

5. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 1, characterized in that: The anti-aging crosslinking agent is prepared by the following steps: Step A: adding 25-30 parts by weight of chloroacetyl chloride to 150 parts by weight of dichloromethane, and then dropping 100-120 parts by weight of 2,4-dihydroxybenzophenone solution while stirring in an ice bath, and continuing to stir for 4-6 hours at room temperature after the dropwise addition, and purifying to obtain component A; the 2,4-dihydroxybenzophenone solution refers to a mixture of 2,4-dihydroxybenzophenone, triethylamine and dichloromethane in a mass ratio of 3:2.5:10-12, stirred at room temperature for 15-30 minutes to obtain a mixture; Step B: Add 10 parts by weight of component A and 6-8 parts by weight of triethylamine to 100 parts by weight of dichloromethane, then dropwise add 18-20 parts by weight of ethylenediamine at room temperature while stirring, continue stirring for 2-4 hours after the addition is complete, and purify to obtain component B; Step C: Add 6 parts by weight of component B and 0.5-1 parts by weight of glycidyl methacrylate to 100 parts by weight of dichloromethane, then stir and mix for 10-12 hours at room temperature in the dark, and purify to complete the preparation.

6. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 5, characterized in that: The purification in step A refers to adding 300 parts by weight of deionized water, shaking, standing for 5-10 minutes to separate layers, removing the lower layer, and then distilling and concentrating at 45-50° C. to 8-10% of the original volume to obtain a first component, adding methanol of an equal volume to the first component, stirring for 5-10 minutes to mix, then distilling and concentrating at 45-50° C. to 45-50% of the original volume, naturally cooling to room temperature, standing for 5-10 minutes, filtering, removing the filtrate, re-adding 30 parts by weight of dichloromethane and 400-500 parts by weight of petroleum ether, stirring for 20-30 minutes to mix, filtering, taking the filter residue, and finally vacuum drying at 40-60° C. until constant weight.

7. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 5, characterized in that: The purification in step B refers to adding 200 parts by weight of deionized water, shaking, standing for 5-10 minutes to separate the layers, taking the lower layer, and then distilling at 45-50° C. until the volatiles are completely removed.

8. The high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 5, characterized in that: The purification in step C refers to distillation at 40° C. until the volatiles are completely removed.

9. A method for preparing a high-strength, aging-resistant, radiation-cross-linked polyethylene pipe according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: The polyethylene resin, lubricant and anti-aging cross-linking agent are added into a mixer for mixing, and then extruded into a tube by a tube extruder, and finally irradiated by an electron accelerator to complete the preparation.

10. The method for preparing a high-strength aging-resistant radiation cross-linked polyethylene pipe according to claim 9, characterized in that: The irradiation dose of the irradiation is 100-125KGy.

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