Polyethylene composite material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of composite materials, in particular to a polyethylene composite material and a preparation method and application thereof. According to the invention, graphene oxide is compounded with cerium dioxide and titanium dioxide to construct an embedded carbon nanostructure, the obtained embedded carbon material not only can effectively avoid the problem that graphene oxide is easy to agglomerate, but also can enable cerium dioxide, titanium dioxide and graphene oxide to generate a synergistic effect in performance, so that each component fully plays a role, and the performance of the material is improved. The mechanical property and the high temperature resistance of the polyethylene composite material can be effectively improved. On the basis, a composite cross-linking agent is adopted, and polyethylene is efficiently cross-linked, so that on one hand, stable distribution of the embedded carbon material in the polyethylene composite material is ensured, and on the other hand, the compatibility and connectivity of the polyethylene and the embedded carbon material are improved; therefore, the polyethylene composite material provided by the invention has better compression resistance and integrity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite materials, and particularly relates to a polyethylene composite material and a preparation method and application thereof. BACKGROUND

[0002] The polyethylene pipe material is a pipe material made of polyethylene (PE) as raw material, which has excellent electrical insulation performance, chemical resistance and waterproof performance, and is widely used in fields such as gas, water supply and drainage and industrial pipelines.

[0003] With the continuous development of manufacturing, construction and engineering fields, the service conditions of PE pipe materials also face significant changes. For example, how to ensure the good service state of PE pipe materials in high temperature environment, whether the integrity and reliability of PE pipe materials can be ensured under high pressure conditions, and whether the shape and shape recovery ability of PE pipe materials can be maintained under the action of large external force. Therefore, it is required that the PE pipe material has good mechanical properties, and at the same time has excellent high temperature resistance and pressure resistance.

[0004] In summary, it is of great significance to develop a PE pipe material with good mechanical properties, high temperature resistance and pressure resistance. SUMMARY

[0005] Therefore, the present application provides a polyethylene composite material and a preparation method and application thereof. The polyethylene composite material provided by the present application has excellent mechanical properties, high temperature resistance and pressure resistance.

[0006] The present application provides a polyethylene composite material, which comprises the following components in mass fraction: 100 parts of polyethylene, 23-29 parts of embedded carbon material, 1-4 parts of composite crosslinking agent, 0.3-0.7 parts of antioxidant, 3-8 parts of flame retardant, 1-3 parts of plasticizer and 2-5 parts of lubricant; the embedded carbon material comprises graphene oxide and rare earth oxide coated on the surface of the graphene oxide; the rare earth oxide comprises cerium dioxide and titanium dioxide; the composite crosslinking agent comprises vinyl triethoxysilane and diethylene triamine.

[0007] Preferably, the number average molecular weight of the polyethylene is 10000-50000.

[0008] Preferably, in the embedded carbon material, the mass ratio of graphene oxide to rare earth oxide is 100:95-130.

[0009] Preferably, in the rare earth oxide, the molar ratio of cerium dioxide to titanium dioxide is 10:3-6.

[0010] Preferably, the mass ratio of vinyl triethoxysilane to diethylene triamine is 1-3:1.

[0011] The application further provides a preparation method of the polyethylene composite material. (1) mixing graphene oxide, water, cerium trichloride and titanium trichloride to carry out precipitation and heat treatment, to obtain an intercalated carbon material; (2) mixing the intercalated carbon material with polyethylene, a composite crosslinking agent dispersion liquid, an antioxidant, a flame retardant, a plasticizer and a lubricant, and sequentially carrying out melt extrusion and granulation, to obtain the polyethylene composite material.

[0012] Preferably, the flake diameter of the graphene oxide is 1-5 microns.

[0013] Preferably, the melt extrusion equipment comprises a double screw extruder; and the melt extrusion conditions comprise: a feeding zone of 100-130 DEG C, a melting zone of 170-200 DEG C, a mixing zone of 190-220 DEG C, a venting zone of 195-215 DEG C, and a die head zone of 180-190 DEG C; and the screw rotation speed is 30-50 rpm.

[0014] The application further provides an application of the polyethylene composite material or the polyethylene composite material prepared by the preparation method in the field of engineering pipes.

[0015] The application further provides a polyethylene pipe, wherein the raw material of the polyethylene pipe comprises the polyethylene composite material or the polyethylene composite material prepared by the preparation method.

[0016] The application provides a polyethylene composite material. The application composites graphene oxide with cerium dioxide and titanium dioxide to construct an intercalated carbon nano structure, so that the obtained intercalated carbon material can not only effectively avoid the problem of easy agglomeration of graphene oxide, but also can produce a synergistic effect between cerium dioxide, titanium dioxide and graphene oxide in performance, so that each component can fully play a role, and the mechanical property and high temperature resistance of the polyethylene composite material can be effectively improved. On this basis, the application further adopts a composite crosslinking agent to effectively crosslink the polyethylene, which can on the one hand ensure the stable distribution of the intercalated carbon material in the polyethylene composite material, and on the other hand improve the compatibility and connectivity of the polyethylene and the intercalated carbon material, so that the compression resistance and integrity of the polyethylene composite material provided by the application are better. Therefore, the polyethylene composite material provided by the application has excellent mechanical property, high temperature resistance and compression resistance, and can better meet the higher performance requirements in various fields.

[0017] The application further provides a preparation method of the polyethylene composite material. The preparation method provided by the application has simple steps, convenient operation, good safety, stable process and potential for large-scale industrial production.

[0018] The application further provides application of the polyethylene composite material in the field of engineering pipes.

[0019] The application further provides a polyethylene pipe. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the application, the drawings used in the embodiments of the application and the prior art are briefly introduced as follows. For those skilled in the art, other drawings can be obtained without creative effort on the basis of the following drawings, and all the drawings are within the protection scope of the application.

[0021] Figure 1 The bending strength results of the polyethylene composite materials of Examples 1-7 and Comparative Examples 1-5. DETAILED DESCRIPTION

[0022] The application provides a polyethylene composite material, which comprises the following components in parts by mass: 100 parts of polyethylene, 23-29 parts of inlaid carbon material, 1-4 parts of composite crosslinking agent, 0.3-0.7 parts of antioxidant, 3-8 parts of flame retardant, 1-3 parts of plasticizer and 2-5 parts of lubricant; the inlaid carbon material comprises graphene oxide and rare earth oxide coated on the surface of the graphene oxide; the rare earth oxide comprises cerium dioxide and titanium dioxide; and the composite crosslinking agent comprises vinyltriethoxysilane and diethylenetriamine.

[0023] According to parts by mass, the polyethylene composite material provided by the application comprises 100 parts of polyethylene; the number average molecular weight of the polyethylene is preferably 10000-50000, more preferably 20000-40000, and further preferably 30000.

[0024] According to parts by mass of the polyethylene, the polyethylene composite material provided by the application comprises 23-29 parts of inlaid carbon material, preferably 24.5-27.5 parts, more preferably 25-26.5 parts, and further preferably 26 parts.

[0025] In the application, the mass ratio of graphene oxide to rare earth oxide in the inlaid carbon material is preferably 100:95-130, more preferably 100:100-120, and further preferably 100:105-110.

[0026] In the present application, the molar ratio of cerium dioxide and titanium dioxide in the rare earth oxide is preferably 10:3~6, more preferably 10:3.5~5.5, and further preferably 10:4~5.

[0027] The polyethylene composite material provided by the present application comprises 1~4 parts of the composite crosslinking agent, preferably 1.7~3.4 parts, more preferably 2.4~3 parts, and further preferably 2.8 parts, based on the mass fraction of the polyethylene.

[0028] In the present application, the vinyl triethoxysilane in the composite crosslinking agent is preferably vinyl triethoxysilane A151.

[0029] In the present application, the mass ratio of the vinyl triethoxysilane and diethylenetriamine is preferably 1~3:1, and more preferably 2:1.

[0030] The polyethylene composite material provided by the present application comprises 0.3~0.7 parts of the antioxidant, preferably 0.4~0.6 parts, and more preferably 0.4~0.5 parts, based on the mass fraction of the polyethylene.

[0031] In the present application, the antioxidant preferably comprises one or more of antioxidant 1010, antioxidant 1076, and dilaurylthiodipropionate.

[0032] The polyethylene composite material provided by the present application comprises 3~8 parts of the flame retardant, preferably 4~7 parts, and more preferably 5~6 parts, based on the mass fraction of the polyethylene.

[0033] In the present application, the flame retardant preferably comprises decabromobiphenyl ether.

[0034] The polyethylene composite material provided by the present application comprises 1~3 parts of the plasticizer, preferably 1~2 parts, and more preferably 1.5 parts, based on the mass fraction of the polyethylene.

[0035] In the present application, the plasticizer preferably comprises dioctyl terephthalate.

[0036] The polyethylene composite material provided by the present application comprises 2~5 parts of the lubricant, preferably 3~5 parts, and more preferably 3~4 parts, based on the mass fraction of the polyethylene.

[0037] In the present application, the lubricant preferably comprises one or more of calcium stearate and paraffin wax.

[0038] The present application also provides a preparation method of the polyethylene composite material described in the above scheme, comprising the following steps: (1) mixing graphene oxide, water, cerium chloride, and titanium chloride, precipitating, and then heat treating to obtain an intercalated carbon material; (2) The carbon intercalation material is mixed with polyethylene, a composite crosslinking agent dispersion liquid, an antioxidant, a flame retardant, a plasticizer and a lubricant, and sequentially melt-extruded and granulated to obtain the polyethylene composite material.

[0039] The present application mixes graphene oxide, water, cerium trichloride and titanium trichloride (denoted as first mixing), performs heat treatment after precipitation, and obtains a carbon intercalation material. In the present application, the flake diameter of the graphene oxide is preferably 1-5 microns, and more preferably 2-4 microns.

[0040] In the present application, the water is preferably deionized water.

[0041] In the present application, the mass ratio of the graphene oxide and water is preferably 0.1-1:1000, more preferably 0.3-0.8:1000, and further preferably 0.5-0.6:1000.

[0042] In the present application, the cerium trichloride is preferably cerium chloride heptahydrate (CeCl3·7H2O).

[0043] In the present application, the mass ratio of the graphene oxide and cerium trichloride is preferably 100:50-90, more preferably 100:60-80, and further preferably 100:70.

[0044] In the present application, the molar ratio of the cerium trichloride and titanium trichloride is preferably 10:2-8, more preferably 10:3-7, and further preferably 10:4-6.

[0045] In the present application, the first mixing preferably includes the following steps: ultrasonic dispersion of graphene oxide and water to obtain a graphene oxide dispersion liquid, and then stirring and mixing the graphene oxide dispersion liquid with cerium trichloride and titanium trichloride.

[0046] In the present application, the frequency of the ultrasonic dispersion is preferably 40-60 KHz, and more preferably 50 KHz, the power is preferably 400-700 W, and more preferably 500-600 W, and the ultrasonic dispersion time is preferably 10-20 minutes, and more preferably 15 minutes.

[0047] In the present application, the stirring and mixing speed is preferably 300-500 rpm, and more preferably 400 rpm, and the stirring and mixing time is preferably 20-30 minutes, and more preferably 25 minutes.

[0048] In the present application, the precipitation temperature is preferably 40-50 degrees Celsius, and more preferably 45 degrees Celsius, and the incubation time is preferably 60-90 minutes, and more preferably 70-80 minutes; the precipitation is preferably performed under stirring conditions; the stirring speed is preferably 200-300 rpm; and the pH value of the precipitation is preferably 5-6.5, and more preferably 5.5.

[0049] In this invention, the precipitation process preferably further includes centrifuging, washing, and drying the resulting product in sequence; the washing agent is preferably water; the drying temperature is preferably 70-80 degrees Celsius, and the holding time is preferably 50-80 minutes, more preferably 60-70 minutes.

[0050] In this invention, the heat treatment temperature is preferably 560-620 degrees Celsius, more preferably 580-600 degrees Celsius, and the holding time is preferably 2-5 hours, more preferably 3-4 hours; the heat treatment atmosphere is preferably air.

[0051] After obtaining the embedded carbon material, the present invention mixes the embedded carbon material with polyethylene, a composite crosslinking agent dispersion, an antioxidant, a flame retardant, a plasticizer, and a lubricant, and then sequentially performs melt extrusion and granulation to obtain the polyethylene composite material. In the present invention, the composite crosslinking agent dispersion preferably includes a composite crosslinking agent and ethanol; the concentration of the composite crosslinking agent dispersion is preferably 1~5wt%, more preferably 2~4wt%.

[0052] In this invention, the amount of the composite crosslinking agent dispersion added is based on the mass fraction of the composite crosslinking agent in the polyethylene composite material described above.

[0053] In this invention, the equipment for melt extrusion preferably includes a twin-screw extruder; the conditions for melt extrusion preferably include: 100~130℃ in the feeding zone, 170~200℃ in the melting zone, 190~220℃ in the mixing zone, 195~215℃ in the venting zone, and 180~190℃ in the die head zone; and a screw speed of 30~50 rpm.

[0054] In this invention, the granulation is preferably performed using cold water granulation.

[0055] The present invention also provides the application of the polyethylene composite material described in the above-described scheme or the polyethylene composite material obtained by the preparation method described in the above-described scheme in the field of engineering pipes.

[0056] The present invention also provides a polyethylene pipe, wherein the raw material of the polyethylene pipe includes the polyethylene composite material described in the above scheme or the polyethylene composite material obtained by the preparation method described in the above scheme.

[0057] To further illustrate the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and embodiments.

[0058] Example 1: This embodiment provides a polyethylene composite material with the following specific components: 100 grams of polyethylene with a number-average molecular weight of 10,000 to 20,000. The intercalated carbon material 23 grams, the intercalated carbon material is graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide, wherein the molar ratio of cerium dioxide and titanium dioxide is 10:3, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:95; The composite crosslinking agent 1.7 grams, the mass ratio of vinyl triethoxysilane A151 and diethylenetriamine is 2:1; Dilaurylthiopropionate 0.5 grams; Decabromodiphenyl ether flame retardant 8 grams; Dioctyl terephthalate plasticizer 1.5 grams; Calcium stearate 4 grams.

[0059] This embodiment prepares a polyethylene composite material, and the specific steps are as follows: (1) The graphene oxide 1 gram with a flake diameter of 2-5 microns and deionized water 1000 grams are ultrasonically dispersed for 10 minutes at a frequency of 60 KHz and a power of 600 W to obtain a graphene oxide dispersion liquid, then the obtained graphene oxide dispersion liquid is mixed with cerium chloride heptahydrate 0.65 grams and titanium trichloride at a stirring speed of 400 rpm for 25 minutes, the molar ratio of cerium chloride heptahydrate and titanium trichloride is controlled to be 10:3.5, then the system is precipitated at 200 rpm for 60 minutes at 50 degrees Celsius, the pH value of the system is controlled to be in the range of 5-6.5, after the precipitation is completed, the product is centrifuged, washed with water, and dried at 70 degrees Celsius for 80 minutes, and then heat treated at 600 degrees Celsius for 4 hours to obtain an intercalated carbon material.

[0060] (2) The prepared intercalated carbon material is mixed with polyethylene, a composite crosslinking agent ethanol dispersion liquid with a concentration of 5wt%, an antioxidant, a flame retardant, a plasticizer, and a lubricant, and then melt extruded by using a double screw extruder, the feeding zone is at 120 degrees Celsius, the melting zone is at 190 degrees Celsius, the mixing zone is at 210 degrees Celsius, the exhaust zone is at 205 degrees Celsius, the die head zone is at 190 degrees Celsius, and the screw rotation speed is 40 rpm, and then the extruded product is granulated in cold water to obtain a polyethylene composite material.

[0061] Example 2: This embodiment provides a polyethylene composite material, and the specific components are as follows: polyethylene 100 grams, and the number average molecular weight is 10000-20000; The intercalated carbon material 26 grams, the intercalated carbon material is graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide, wherein the molar ratio of cerium dioxide and titanium dioxide is 10:4, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:100; The composite crosslinking agent 3.4 grams, the mass ratio of vinyl triethoxysilane A151 and diethylenetriamine is 2:1; Dilaurylthiopropionate 0.6 grams; Decabromodiphenyl ether flame retardant 7 grams; Dioctyl terephthalate plasticizer 1.5 grams; Calcium stearate 3 grams.

[0062] This example prepared a polyethylene composite material, the specific steps as follows: (1) graphene oxide 1 gram and deionized water 1000 grams of 1~4 micron in diameter were ultrasonically dispersed for 20 minutes, frequency 40 KHz, power 400 W, to obtain graphene oxide dispersion, then the obtained graphene oxide dispersion was mixed with cerium chloride 0.7 grams and titanium trichloride at a stirring speed of 400 rpm for 30 minutes, the molar ratio of cerium chloride and titanium trichloride was controlled to be 10:4.5, then under the condition of 200 rpm stirring, 40 degrees Celsius, precipitated for 80 minutes, the pH value of the system was controlled within the range of 5~6.5, after the completion of the precipitation, the product was centrifuged, washed with water, dried at 80 degrees Celsius for 50 minutes, and then heat treated at 600 degrees Celsius for 3 hours to obtain an intercalated carbon material.

[0063] (2) the prepared intercalated carbon material was mixed with polyethylene, a composite crosslinking agent ethanol dispersion solution with a concentration of 5wt%, an antioxidant, a flame retardant, a plasticizer and a lubricant, and then melt extruded by using a double screw extruder, the feeding zone was 100℃, the melting zone was 170℃, the mixing zone was 190℃, the exhaust zone was 195℃, the head zone was 180℃, and the screw rotation speed was 30 rpm, after extrusion, the product was granulated in cold water to obtain a polyethylene composite material.

[0064] Example 3: This example provides a polyethylene composite material, the specific components are as follows: polyethylene 100 grams, number average molecular weight 10000~20000; Intercalated carbon material 27.5 grams, the intercalated carbon material is composed of graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide, the molar ratio of cerium dioxide and titanium dioxide is 10:5, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:105; Composite crosslinking agent 2.8 grams, the mass ratio of vinyl triethoxy silane A151 and diethylene triamine is 1:1; Dilaurylthiopropionate 0.5 grams; Decabromodiphenyl ether flame retardant 3 grams; Dioctyl terephthalate plasticizer 1.5 grams; Calcium stearate 4 grams.

[0065] This example prepared a polyethylene composite material, the specific steps as follows: (1) 1 gram of graphene oxide with a sheet diameter of 1-4 micrometers and 1000 grams of deionized water were ultrasonically dispersed for 15 minutes at a frequency of 50 kHz and a power of 500 W to obtain a graphene oxide dispersion. Then, the obtained graphene oxide dispersion was mixed with 0.74 grams of cerium chloride heptahydrate and titanium trichloride at a speed of 400 rpm for 25 minutes, and the molar ratio of cerium trichloride and titanium trichloride was controlled to be 10:5.5. Then, the mixture was precipitated at 50 degrees Celsius for 80 minutes under stirring conditions of 300 rpm, and the pH value of the system was controlled within the range of 5-6.5. After precipitation, the product was centrifuged, washed with water, dried at 75 degrees Celsius for 60 minutes, and then heat-treated at 600 degrees Celsius for 4 hours to obtain the embedded carbon material.

[0066] (2) The prepared embedded carbon material is mixed with polyethylene, 3wt% composite crosslinking agent ethanol dispersion, antioxidant, flame retardant, plasticizer and lubricant, and melt extruded using a twin-screw extruder with the following temperatures: feed zone 130℃, melt zone 200℃, mixing zone 220℃, exhaust zone 215℃, die head zone 190℃, screw speed 40rpm. After extrusion, the material is granulated with cold water to obtain polyethylene composite material.

[0067] Example 4: This embodiment provides a polyethylene composite material with the following specific components: 100 grams of polyethylene with a number-average molecular weight of 40,000 to 50,000. The embedded carbon material weighs 25 grams and consists of graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide. The molar ratio of cerium dioxide to titanium dioxide is 10:6, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:110. 3 grams of composite crosslinking agent, with a mass ratio of vinyltriethoxysilane A151 to diethylenetriamine of 3:1; 0.6 g of dilauryl thiodipropionate; 5 grams of decabromodiphenyl ether flame retardant; 1.5 grams of dioctyl terephthalate plasticizer; 4 grams of calcium stearate.

[0068] This embodiment prepares a polyethylene composite material, and the specific steps are as follows: (1) 1 gram of graphene oxide with a sheet diameter of 2-5 micrometers and 1000 grams of deionized water were ultrasonically dispersed for 20 minutes at a frequency of 40 kHz and a power of 400 W to obtain a graphene oxide dispersion. Then, the obtained graphene oxide dispersion was mixed with 0.8 grams of cerium chloride heptahydrate and titanium trichloride at a speed of 300 rpm for 20 minutes, and the molar ratio of cerium trichloride and titanium trichloride was controlled to be 10:6.5. Then, the mixture was precipitated at 40 degrees Celsius for 90 minutes under stirring conditions of 200 rpm, and the pH value of the system was controlled at 5-6.5. After precipitation, the product was centrifuged, washed with water, dried at 70 degrees Celsius for 80 minutes, and then heat-treated at 600 degrees Celsius for 3 hours to obtain the embedded carbon material.

[0069] (2) The prepared embedded carbon material is mixed with polyethylene, 3wt% composite crosslinking agent ethanol dispersion, antioxidant, flame retardant, plasticizer and lubricant, and melt extruded using a twin-screw extruder with the following temperatures: feed zone 130℃, melt zone 200℃, mixing zone 220℃, exhaust zone 215℃, die head zone 190℃, screw speed 45rpm. After extrusion, the material is granulated with cold water to obtain polyethylene composite material.

[0070] Example 5: This embodiment provides a polyethylene composite material with the following specific components: 100 grams of polyethylene with a number-average molecular weight of 40,000 to 50,000. The embedded carbon material weighs 29 grams and consists of graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide. The molar ratio of cerium dioxide to titanium dioxide is 10:5.5, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:120. 4 grams of composite crosslinking agent, with a mass ratio of vinyltriethoxysilane A151 and diethylenetriamine of 1:1; 0.6 g of dilauryl thiodipropionate; 6 grams of decabromodiphenyl ether flame retardant; 1.5 grams of dioctyl terephthalate plasticizer; 4 grams of calcium stearate.

[0071] This embodiment prepares a polyethylene composite material, and the specific steps are as follows: (1) 0.8 g of graphene oxide with a sheet diameter of 1-4 micrometers and 1000 g of deionized water were ultrasonically dispersed for 20 minutes at a frequency of 60 kHz and a power of 400 W to obtain a graphene oxide dispersion. Then, the obtained graphene oxide dispersion was mixed with 0.9 g of cerium chloride heptahydrate and titanium trichloride at a speed of 300 rpm for 30 minutes, and the molar ratio of cerium trichloride and titanium trichloride was controlled to be 10:6. Then, the mixture was precipitated at 50 degrees Celsius for 60 minutes under stirring conditions of 200 rpm. The pH value of the system was controlled within the range of 5-6.5. After precipitation, the product was centrifuged, washed with water, dried at 80 degrees Celsius for 50 minutes, and then heat-treated at 620 degrees Celsius for 4 hours to obtain the embedded carbon material.

[0072] (2) The prepared embedded carbon material is mixed with polyethylene, 5 wt% composite crosslinking agent ethanol dispersion, antioxidant, flame retardant, plasticizer and lubricant, and melt extruded using a twin-screw extruder with the following temperatures: feed zone 100°C, melt zone 170°C, mixing zone 190°C, exhaust zone 200°C, die head zone 180°C, screw speed 35 rpm. After extrusion, the material is granulated with cold water to obtain polyethylene composite material.

[0073] Example 6: This embodiment provides a polyethylene composite material with the following specific components: 100 grams of polyethylene with a number-average molecular weight of 40,000 to 50,000. The embedded carbon material weighs 27.5 grams and consists of graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide. The molar ratio of cerium dioxide to titanium dioxide is 10:6, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:100. 2.4 g of composite crosslinking agent, with a mass ratio of vinyltriethoxysilane A151 to diethylenetriamine of 2:1; Antioxidant 1010 0.4 g; 6 grams of decabromodiphenyl ether flame retardant; 1.5 grams of dioctyl terephthalate plasticizer; 4 grams of calcium stearate.

[0074] This embodiment prepares a polyethylene composite material, and the specific steps are as follows: (1) 1 gram of graphene oxide with a sheet diameter of 1-4 micrometers and 1000 grams of deionized water were ultrasonically dispersed for 10 minutes at a frequency of 40 kHz and a power of 400 W to obtain a graphene oxide dispersion. Then, the obtained graphene oxide dispersion was mixed with 0.68 grams of cerium chloride heptahydrate and titanium trichloride at a speed of 400 rpm for 30 minutes, and the molar ratio of cerium trichloride and titanium trichloride was controlled to be 10:6.5. Then, the mixture was precipitated at 50 degrees Celsius for 90 minutes under stirring conditions of 200 rpm, and the pH value of the system was controlled in the range of 5-6.5. After precipitation, the product was centrifuged, washed with water, dried at 80 degrees Celsius for 80 minutes, and then heat-treated at 620 degrees Celsius for 2 hours to obtain the embedded carbon material.

[0075] (2) The prepared embedded carbon material is mixed with polyethylene, 5 wt% composite crosslinking agent ethanol dispersion, antioxidant, flame retardant, plasticizer and lubricant, and melt extruded using a twin-screw extruder with the following temperatures: feed zone 110°C, melt zone 180°C, mixing zone 200°C, exhaust zone 205°C, die head zone 185°C, screw speed 35 rpm. After extrusion, the material is granulated with cold water to obtain polyethylene composite material.

[0076] Example 7: This embodiment provides a polyethylene composite material with the following specific components: 100 grams of polyethylene with a number-average molecular weight of 10,000 to 20,000. The embedded carbon material weighs 26.5 grams and consists of graphene oxide and cerium dioxide and titanium dioxide coated on the surface of graphene oxide. The molar ratio of cerium dioxide to titanium dioxide is 10:3, and the mass ratio of graphene oxide to the total mass of cerium dioxide and titanium dioxide is 100:130. 3 grams of composite crosslinking agent, wherein the mass ratio of vinyltriethoxysilane A151 to diethylenetriamine is 3:1; Antioxidant 1010 0.3 g; 8 grams of decabromodiphenyl ether flame retardant; 1.5 grams of dioctyl terephthalate plasticizer; 3 grams of calcium stearate.

[0077] This embodiment prepares a polyethylene composite material, and the specific steps are as follows: (1) 0.2 g of graphene oxide with a sheet diameter of 1-4 micrometers and 1000 g of deionized water were ultrasonically dispersed for 20 minutes at a frequency of 40 kHz and a power of 400 W to obtain a graphene oxide dispersion. Then, the obtained graphene oxide dispersion was mixed with 0.55 g of cerium chloride heptahydrate and titanium trichloride at a speed of 400 rpm for 25 minutes, and the molar ratio of cerium trichloride and titanium trichloride was controlled to be 100:3.5. Then, the mixture was precipitated at 50 degrees Celsius for 90 minutes under stirring conditions of 300 rpm. The pH value of the system was controlled within the range of 5-6.5. After precipitation, the product was centrifuged, washed with water, dried at 80 degrees Celsius for 70 minutes, and then heat-treated at 560 degrees Celsius for 5 hours to obtain the embedded carbon material.

[0078] (2) The prepared embedded carbon material is mixed with polyethylene, 5 wt% composite crosslinking agent ethanol dispersion, antioxidant, flame retardant, plasticizer and lubricant, and melt extruded using a twin-screw extruder. The feed zone is controlled at 100°C, the melt zone at 170°C, the mixing zone at 190°C, the exhaust zone at 195°C, the die head zone at 180°C, and the screw speed at 30 rpm. After extrusion, the material is granulated with cold water to obtain a polyethylene composite material.

[0079] Comparative Example 1: The preparation method of this comparative example is the same as that of Example 1, except that the embedded carbon material is replaced with graphene oxide sheets, cerium dioxide powder and titanium dioxide powder of equal total mass and in the same proportion.

[0080] Comparative Example 2: The preparation method of this comparative example is the same as that of Example 1, except that the cerium dioxide powder in the embedded carbon material is replaced with an equal mass of titanium dioxide powder.

[0081] Comparative Example 3: The preparation method of this comparative example is the same as that of Example 1, except that the titanium dioxide powder in the embedded carbon material is replaced with an equal mass of cerium dioxide powder.

[0082] Comparative Example 4: The preparation method of this comparative example is the same as that of Example 1, except that diethylenetriamine is replaced with an equal mass of vinyltriethoxysilane A151.

[0083] Comparative Example 5: The preparation method of this comparative example is the same as that of Example 1, except that vinyltriethoxysilane A151 is replaced with an equal mass of diethylenetriamine.

[0084] Test Example 1: Mechanical properties of the polyethylene composites prepared in Examples 1-7 and Comparative Examples 1-5 were tested. The testing method was as follows: using a single-screw extruder and a multi-stage vacuum sizing chamber, the above polyethylene composites were respectively prepared into PE pipes with a diameter of 50 mm and a wall thickness of 3.7 mm. Then, according to GB / T 13663, samples of the prepared PE pipes were taken for testing of bending strength and elongation at break. The test results are shown in Table 1 and 2. Figure 1 As shown.

[0085] Table 1. Mechanical property test results of Examples 1-7 and Comparative Examples 1-5:

[0086] According to Table 1 and Figure 1 It can be seen that the polyethylene composite material provided by this invention has significantly better mechanical properties than the comparative example, meeting the mechanical performance requirements for pipe materials in the water supply and drainage field, and exhibiting balanced and excellent overall mechanical properties. This is because the structure of the embedded carbon material helps rare earth oxides and graphene oxide to fully exert their respective roles and produce a good synergistic effect, which provides a new approach to the modification of polyethylene materials.

[0087] Test Example 2: The compressive strength and high temperature resistance of the polyethylene composite materials prepared in Examples 1-7 and Comparative Examples 1-5 were tested. The sample prepared in Test Example 1 was subjected to a hydraulic test for 165 hours at 80 degrees Celsius and 5.4 MPa, in accordance with GB / T 13663. The results are shown in Table 2.

[0088] Table 2. Results of compressive strength and high temperature resistance tests for Examples 1-7 and Comparative Examples 1-5:

[0089] As shown in Table 2, the polyethylene composite material provided by this invention can meet the compressive strength requirements of PE pipes and is far superior to the comparative example. It can also be seen that the polyethylene composite material provided by this invention has excellent high-temperature resistance (80 degrees Celsius). This further proves that the polyethylene composite material provided by this invention, by utilizing embedded carbon materials and composite crosslinking agents, achieves a simultaneous and significant improvement in both compressive strength and high-temperature resistance.

[0090] The embodiments of the present invention have been described above; however, these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. All other embodiments obtained by those skilled in the art based on the above embodiments of the present invention without inventive effort are within the protection scope of the present invention.

Claims

1. A polyethylene composite material, characterized in that, It comprises the following components in parts by weight: 100 parts polyethylene, 23-29 parts embedded carbon material, 1-4 parts composite crosslinking agent, 0.3-0.7 parts antioxidant, 3-8 parts flame retardant, 1-3 parts plasticizer, and 2-5 parts lubricant; The embedded carbon material includes graphene oxide and rare earth oxides coated on the surface of the graphene oxide. The rare earth oxides include cerium dioxide and titanium dioxide; The composite crosslinking agent includes vinyltriethoxysilane and diethylenetriamine.

2. The polyethylene composite material according to claim 1, characterized in that, The number average molecular weight of the polyethylene is 10,000 to 50,000.

3. The polyethylene composite material according to claim 1, characterized in that, In the embedded carbon material, the mass ratio of graphene oxide to rare earth oxide is 100:95~130.

4. The polyethylene composite material according to claim 1 or 3, characterized in that, In the rare earth oxide, the molar ratio of cerium dioxide to titanium dioxide is 10:3~6.

5. The polyethylene composite material according to claim 1, characterized in that, The mass ratio of vinyltriethoxysilane to diethylenetriamine is 1~3:

1.

6. A method for preparing the polyethylene composite material according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Graphene oxide, water, cerium trichloride and titanium trichloride were mixed, precipitated and then heat-treated to obtain carbon-embedded materials; (2) The embedded carbon material is mixed with polyethylene, composite crosslinking agent dispersion, antioxidant, flame retardant, plasticizer and lubricant and then melt-extruded and granulated in sequence to obtain the polyethylene composite material.

7. The preparation method according to claim 6, characterized in that, The graphene oxide sheets have a diameter of 1 to 5 micrometers.

8. The preparation method according to claim 6, characterized in that, The equipment for melt extrusion includes a twin-screw extruder; the conditions for melt extrusion include: feed zone 100~130℃, melting zone 170~200℃, mixing zone 190~220℃, venting zone 195~215℃, die head zone 180~190℃; screw speed 30~50rpm.

9. The application of the polyethylene composite material according to any one of claims 1 to 5 or the polyethylene composite material obtained by the preparation method according to any one of claims 7 to 8 in the field of engineering pipes.

10. A polyethylene pipe, characterized in that, The raw materials for the polyethylene pipe include the polyethylene composite material according to any one of claims 1 to 5 or the polyethylene composite material obtained by the preparation method according to any one of claims 7 to 8.

Images