Anti-aging tpe composite material and preparation method thereof

Abstract

The application belongs to the technical field of polymer materials, and particularly relates to an anti-aging TPE composite material and a preparation method thereof. The application uses alpha-olefin block copolymer I as a carrier of an anti-aging agent, forms an "anti-aging agent-compatibility agent alpha-olefin block copolymer" pre-dispersed composite through synergistic action of the compatibility agent, avoids volatilization or degradation of the anti-aging agent under high temperature in a processing process, improves effective utilization of raw materials, and can significantly reduce agglomeration of the anti-aging agent, so that the anti-aging agent is more uniformly dispersed in a matrix, thereby more effectively capturing free radicals, absorbing ultraviolet rays or inhibiting oxidation reaction, and improving long-term anti-aging performance of the material. PBS and EVOH are premixed to form a polar phase water suspension, and then melt blending is performed, so that the interface compatibility of polar and non-polar components is effectively improved, phase separation is reduced, and overall mechanical properties (such as tensile strength and toughness), anti-aging performance and processing stability of the material are improved.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to an anti-aging TPE composite material and its preparation method. Background Technology

[0002] Thermoplastic elastomers (TPEs), as materials combining the properties of rubber and plastics, are widely used in many fields. However, existing TPE materials are susceptible to aging due to environmental factors such as light, oxygen, and high temperatures during long-term use, leading to a decline in material properties, such as increased hardness, reduced elasticity, and surface cracking, thus limiting their service life and application range. Therefore, developing a TPE composite material with excellent anti-aging properties is of significant practical importance.

[0003] Currently, the preparation methods for commonly used anti-aging TPE materials on the market often have some shortcomings. For example, some methods improve the anti-aging performance of materials by adding a large amount of anti-aging agents, but this not only increases costs but may also affect other properties of the materials; other methods, although improving anti-aging performance to some extent, have complex preparation processes that are not conducive to large-scale production. Summary of the Invention

[0004] The purpose of this invention is to address existing problems by providing an anti-aging TPE composite material and its preparation method.

[0005] This invention is achieved through the following technical solution:

[0006] An anti-aging TPE composite material comprises the following components in parts by weight: 60-90 parts of α-olefin block copolymer, 30-45 parts of polybutylene succinate (PBS), 8-15 parts of ethylene-vinyl alcohol copolymer (EVOH), 5-8 parts of hyperbranched polyethylene, 4-8 parts of anti-aging agent, 1-2 parts of dicumyl peroxide (DCP), and 3-5 parts of maleic anhydride graft.

[0007] Furthermore, the method for preparing the anti-aging agent is as follows: modified lignin and modified nano zinc oxide are added to a high-speed mixer at a mass ratio of 1:0.6~1 and mixed at a speed of 800~1000r / min for 10~20min. Then, light stabilizer 770 and antioxidant 1010 are added and mixed evenly to obtain the anti-aging agent.

[0008] Furthermore, the light stabilizer 770 and antioxidant 1010 account for 1-3% of the total mass of the modified lignin and modified nano zinc oxide, respectively.

[0009] Further, the preparation method of the modified lignin is as follows: lignin is added to a NaOH solution with a mass fraction of 5-10%, and stirred at 50-60℃ to form a lignin solution. Then, an acrylate monomer containing a hindered phenolic structure is added to the lignin solution, stirred and mixed, and potassium persulfate is added. The temperature is raised to 70-80℃ and reacted for 4-5 hours. After the reaction is completed, the mixture is cooled to room temperature, the pH is adjusted to neutral with hydrochloric acid, ethanol is added to precipitate the product, filtered, washed with ethanol, and dried at 60-70℃ to constant weight to obtain the modified lignin.

[0010] Furthermore, the mass ratio of the hindered phenolic acrylate monomer to lignin is 1:2~5;

[0011] The mass ratio of potassium persulfate to hindered phenolic acrylate monomers is 1:40~60.

[0012] Furthermore, the preparation of the modified nano zinc oxide includes the following steps:

[0013] 1) Nano zinc oxide (purity ≥99.5%, particle size 30~50nm) and hexadecyltrimethylammonium bromide were ultrasonically dispersed in deionized water at a mass ratio of 1:3~5. After uniform dispersion, the temperature was raised to 120~130℃ and reacted at a constant temperature for 4~5h. After centrifugation, the mixture was washed with ethanol and deionized water in sequence, and then vacuum dried at 60~70℃ for 10~12h. After ultrasonic dispersion in 1M hydrochloric acid solution, the mixture was ultrasonically treated for 1~2h and then centrifuged. The precipitate was collected and calcined at 400~500℃ for 2~3h to obtain mesoporous zinc oxide.

[0014] 2) Dissolve cerium nitrate in deionized water to form a cerium nitrate solution, adjust the pH to 6, then add mesoporous zinc oxide to the cerium nitrate solution, ultrasonically disperse it evenly, stir at 200~300 r / min for 2~3 h, add sodium hydroxide solution dropwise, adjust the pH to 9~10, continue stirring at room temperature for 3~4 h, filter, wash with deionized water, and freeze dry to obtain cerium-doped zinc oxide for later use.

[0015] 3) Disperse cerium-doped zinc oxide into a glucose solution using ultrasound. After uniform dispersion, place it under ultraviolet light at 365 nm for 5-6 hours, stirring at 100-200 r / min during illumination. After centrifugation, wash with ethanol, and vacuum dry at 50-60℃ for 6-8 hours. Then calcine at 400-500℃ under a nitrogen atmosphere for 1-2 hours. Next, introduce air at a rate of 400-500 mL / min and raise the temperature to 500-600℃ for another 0.5-1 hour.

[0016] Further, the mass ratio of cerium nitrate to mesoporous zinc oxide in step 2) is 1:10~30;

[0017] The mass fraction of sodium hydroxide is 10-20%.

[0018] A method for preparing an anti-aging TPE composite material includes the following steps:

[0019] S1. Weigh out the following components by weight: 60-90 parts of α-olefin block copolymer, 30-45 parts of PBS, 8-15 parts of EVOH, 5-8 parts of hyperbranched polyethylene, 4-8 parts of anti-aging agent, 1-2 parts of DCP, and 3-5 parts of maleic anhydride graft.

[0020] S2. The weighed α-olefin block copolymers are divided into α-olefin block copolymer I and α-olefin block copolymer II in a ratio of 2:8. α-olefin block copolymer I, anti-aging agent, and maleic anhydride graft are added sequentially to a high-speed mixer and stirred at 70~80℃ and 500~600r / min for 10~20min. Then, it is added to a ball mill, and anhydrous ethanol is added. The mixture is ground at 300~400r / min for 2~3h to obtain an anti-aging agent dispersion for later use.

[0021] S3. Mix PBS and EVOH and add them to deionized water at 80~90℃. Disperse the mixture by sonication for 30~40 min to form an aqueous suspension. Then add Span-80 and stir at 100~200 r / min for 20~30 min to obtain a polar phase aqueous suspension for later use.

[0022] S4. Add α-olefin block copolymer II, hyperbranched polyethylene, polar phase aqueous suspension, anti-aging agent dispersion, and DCP sequentially into a twin-screw extruder for extrusion granulation.

[0023] Furthermore, in step S2, the solid-liquid ratio is controlled to be 1:2~3 when anhydrous ethanol is added.

[0024] Furthermore, the amount of deionized water added in step S3 is 6 to 10 times the total mass of PBS and EVOH, and the amount of Span-80 added is 0.6 to 1% of the volume of the aqueous suspension.

[0025] The present invention has the following advantages over the prior art:

[0026] 1. Traditional TPE blending often employs direct melt blending, which leads to the tendency of PBS / EVOH to agglomerate and uneven dispersion of the anti-aging agent. This invention utilizes α-olefin block copolymer I as a carrier for the anti-aging agent. Through the synergistic effect of a compatibilizer, a pre-dispersed composite of "anti-aging agent-compatibility α-olefin block copolymer" is formed. This avoids the high-temperature volatilization or degradation of the anti-aging agent silver during processing, improves the effective utilization rate of raw materials, and significantly reduces the agglomeration of the anti-aging agent, resulting in more uniform dispersion in the matrix. This allows for more effective capture of free radicals, absorption of ultraviolet light, or inhibition of oxidation reactions, thereby improving the long-term anti-aging performance of the material. Premixing PBS and EVOH to form a polar aqueous suspension before melt blending effectively improves the interfacial compatibility between polar and non-polar components, reduces phase separation, and enhances the overall mechanical properties (such as tensile strength and toughness), anti-aging performance, and processing stability of the material.

[0027] 2. In the preparation of the modified lignin of this invention, under alkaline conditions, the hydroxyl groups of lignin are grafted onto monomers via a polymerization reaction initiated by potassium persulfate. The grafted lignin not only retains its own antioxidant properties but also introduces new anti-aging groups, improving its ability to capture free radicals and absorb ultraviolet light. Nano-zinc oxide is hydrothermally reacted with CTAB at 120-130°C to form a mesoporous structure, increasing the specific surface area. Then, gradient deposition is achieved by adjusting the pH value in stages. Initially, at pH=6, Ce... 3+ Preferential adsorption occurs at ZnO defect sites. After heating, the pH is adjusted to 9-10, and Ce... 4+ For outer layer deposition, glucose solution is added simultaneously during ultrasonic dispersion. CQDs are deposited on the CeO2 surface using 365nm ultraviolet light irradiation. Oxygen vacancies are generated during calcination in a nitrogen atmosphere at 400℃, followed by rapid calcination in air at 550℃ to stabilize the crystals. Cerium-doped nano-zinc oxide is prepared by mixing nano-zinc oxide with cerium nitrate solution. Cerium doping alters the band structure of nano-zinc oxide, enhancing its absorption and conversion capabilities for ultraviolet light, while also improving its catalytic activity and promoting free radical decomposition, thus enhancing its anti-aging effect. Modified lignin can capture free radicals and inhibit thermal oxidation reactions, while modified nano-zinc oxide can shield and scatter ultraviolet light, reducing UV damage to the material. The combination of these two may produce a synergistic effect, further improving anti-aging performance. Adding a small amount of hindered amine light stabilizer synergistically enhances the UV protection capability of the compound; adding phenolic antioxidants synergistically enhances the resistance to thermal oxidation. Detailed Implementation

[0028] To further explain the present invention, the following specific embodiments are described.

[0029] Example 1

[0030] A method for preparing an anti-aging TPE composite material includes the following steps:

[0031] S1. Weigh out the corresponding weight parts of 60 parts of α-olefin block copolymer, 30 parts of PBS, 8 parts of EVOH, 5 parts of hyperbranched polyethylene, 4 parts of anti-aging agent, 1 part of DCP, and 3 parts of maleic anhydride graft for later use.

[0032] The preparation of the anti-aging agent includes the following steps:

[0033] (1) Add lignin to a 5% NaOH solution and stir at 50°C to form a lignin solution. Then add acrylate monomers containing hindered phenolic structures to the lignin solution. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:2. After stirring and mixing, add potassium persulfate. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:2. Heat to 70°C and react for 4 hours. After the reaction is complete, cool to room temperature, adjust the pH to neutral with hydrochloric acid, add ethanol to precipitate the product, filter, wash with ethanol, and dry at 60°C to constant weight to obtain modified lignin.

[0034] (2) Preparation of modified nano zinc oxide:

[0035] 1) Nano zinc oxide and hexadecyltrimethylammonium bromide were ultrasonically dispersed in deionized water at a mass ratio of 1:3. After uniform dispersion, the mixture was heated to 120℃ and reacted at a constant temperature for 4 hours. After centrifugation, the mixture was washed with ethanol and deionized water in sequence, dried under vacuum at 60℃ for 10-12 hours, ultrasonically dispersed in 1M hydrochloric acid solution, ultrasonically treated for 1 hour, centrifuged, and the precipitate was collected and calcined at 400℃ for 2 hours to obtain mesoporous zinc oxide.

[0036] 2) Dissolve cerium nitrate in deionized water to form a cerium nitrate solution, adjust the pH to 6, and then add mesoporous zinc oxide to the cerium nitrate solution. The mass ratio of cerium nitrate to mesoporous zinc oxide is 1:10. After ultrasonic dispersion, stir at 200 r / min for 2 h, then add 10% sodium hydroxide solution dropwise to adjust the pH to 9. Continue stirring at room temperature for 3 h, filter, wash with deionized water, and freeze dry to obtain cerium-doped zinc oxide for later use.

[0037] 3) Cerium-doped zinc oxide was ultrasonically dispersed in a glucose solution. After uniform dispersion, it was placed under ultraviolet light at 365 nm for 5 hours. During the illumination, the mixture was stirred at 100 r / min. After centrifugation, the mixture was washed with ethanol and vacuum dried at 50°C for 6 hours. Then, it was calcined at 400°C under a nitrogen atmosphere for 1 hour. After that, air was introduced at a rate of 400 mL / min, and the temperature was raised to 500°C for 0.5 hours.

[0038] (3) Add modified lignin and modified nano zinc oxide to a high-speed mixer at a mass ratio of 1:0.6 and mix at 800 r / min for 10 min. Then add 1% stabilizer 770 and 1% antioxidant 1010 and mix evenly to obtain the anti-aging agent.

[0039] S2. The weighed α-olefin block copolymers were divided into α-olefin block copolymer I and α-olefin block copolymer II in a ratio of 2:8. α-olefin block copolymer I, the anti-aging agent, and the maleic anhydride graft were added to a high-speed mixer in sequence and stirred at 70°C and 500 r / min for 10 min. Then, the mixture was added to a ball mill, and anhydrous ethanol (solid-liquid ratio 1:2) was added. The mixture was then ground at 300 r / min for 2 h to obtain an anti-aging agent dispersion for later use.

[0040] S3. Mix PBS and EVOH and add them to deionized water at 80℃. Disperse by sonication for 30 min to form an aqueous suspension. Then add Span-80 and stir at 100 r / min for 20 min to obtain a polar phase aqueous suspension for later use.

[0041] The amount of deionized water added is 6 times the total mass of PBS and EVOH, and the amount of Span-80 added is 0.6% of the volume of the aqueous suspension.

[0042] S4. Add α-olefin block copolymer II, hyperbranched polyethylene, polar phase aqueous suspension, anti-aging agent dispersion, and DCP sequentially into a twin-screw extruder for extrusion granulation.

[0043] Example 2

[0044] A method for preparing an anti-aging TPE composite material includes the following steps:

[0045] S1. Weigh out the corresponding weight parts of 75 parts of α-olefin block copolymer, 40 parts of PBS, 12 parts of EVOH, 6 parts of hyperbranched polyethylene, 6 parts of anti-aging agent, 1.5 parts of DCP, and 4 parts of maleic anhydride graft for later use.

[0046] The preparation of the anti-aging agent includes the following steps:

[0047] (1) Add lignin to a 7% NaOH solution and stir at 55°C to form a lignin solution. Then add acrylate monomers containing hindered phenolic structures to the lignin solution. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:3.5. After stirring and mixing, add potassium persulfate. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:3.5. Heat to 75°C and react for 4.5 hours. After the reaction is complete, cool to room temperature, adjust the pH to neutral with hydrochloric acid, add ethanol to precipitate the product, filter, wash with ethanol, and dry at 65°C to constant weight to obtain modified lignin.

[0048] (2) Preparation of modified nano zinc oxide:

[0049] 1) Nano zinc oxide and hexadecyltrimethylammonium bromide were ultrasonically dispersed in deionized water at a mass ratio of 1:4. After uniform dispersion, the mixture was heated to 125℃ and reacted at a constant temperature for 4.5 h. After centrifugation, the mixture was washed successively with ethanol and deionized water, dried under vacuum at 65℃ for 11 h, and then ultrasonically dispersed in 1M hydrochloric acid solution. After ultrasonic treatment for 1.5 h, the mixture was centrifuged, and the precipitate was collected and calcined at 450℃ for 2.5 h to obtain mesoporous zinc oxide.

[0050] 2) Dissolve cerium nitrate in deionized water to form a cerium nitrate solution, adjust the pH to 6, and then add mesoporous zinc oxide to the cerium nitrate solution. The mass ratio of cerium nitrate to mesoporous zinc oxide is 1:20. After ultrasonic dispersion, stir at 250 r / min for 2.5 h, then add 15% sodium hydroxide solution dropwise to adjust the pH to 9. Continue stirring at room temperature for 3.5 h, filter, wash with deionized water, and freeze-dry to obtain cerium-doped zinc oxide for later use.

[0051] 3) Cerium-doped zinc oxide was ultrasonically dispersed in a glucose solution. After uniform dispersion, it was placed under ultraviolet light at 365 nm for 5.5 h. During the illumination, the mixture was stirred at 150 r / min. After centrifugation, the mixture was washed with ethanol and vacuum dried at 55 °C for 7 h. Then, it was calcined at 450 °C under a nitrogen atmosphere for 1.5 h. After that, air was introduced at a rate of 450 mL / min, and the temperature was raised to 550 °C for calcination for another 0.7 h.

[0052] (3) Add modified lignin and modified nano zinc oxide to a high-speed mixer at a mass ratio of 1:0.8 and mix at a speed of 900 r / min for 15 min. Then add 2% stabilizer 770 and 2% antioxidant 1010 and mix evenly to obtain the anti-aging agent.

[0053] S2. The weighed α-olefin block copolymers were divided into α-olefin block copolymer I and α-olefin block copolymer II in a ratio of 2:8. α-olefin block copolymer I, the anti-aging agent, and the maleic anhydride graft were added sequentially to a high-speed mixer and stirred at 75°C and 550 r / min for 15 min. Then, the mixture was added to a ball mill, and anhydrous ethanol (solid-liquid ratio 1:2.5) was added. The mixture was then ground at 350 r / min for 2.5 h to obtain an anti-aging agent dispersion for later use.

[0054] S3. Mix PBS and EVOH and add them to deionized water at 85℃. Disperse by sonication for 35 minutes to form an aqueous suspension. Then add Span-80 and stir at 150 r / min for 25 minutes to obtain a polar phase aqueous suspension for later use.

[0055] The amount of deionized water added is 8 times the total mass of PBS and EVOH, and the amount of Span-80 added is 0.8% of the volume of the aqueous suspension.

[0056] S4. Add α-olefin block copolymer II, hyperbranched polyethylene, polar phase aqueous suspension, anti-aging agent dispersion, and DCP sequentially into a twin-screw extruder for extrusion granulation.

[0057] Example 3

[0058] A method for preparing an anti-aging TPE composite material includes the following steps:

[0059] S1. Weigh out the corresponding weight parts of 90 parts of α-olefin block copolymer, 45 parts of PBS, 15 parts of EVOH, 8 parts of hyperbranched polyethylene, 8 parts of anti-aging agent, 2 parts of DCP, and 5 parts of maleic anhydride graft for later use.

[0060] The preparation of the anti-aging agent includes the following steps:

[0061] (1) Add lignin to a 10% NaOH solution and stir at 60°C to form a lignin solution. Then add acrylate monomers containing hindered phenolic structures to the lignin solution. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:5. After stirring and mixing, add potassium persulfate. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:5. Heat to 80°C and react for 5 hours. After the reaction is complete, cool to room temperature, adjust the pH to neutral with hydrochloric acid, add ethanol to precipitate the product, filter, wash with ethanol, and dry at 70°C to constant weight to obtain modified lignin.

[0062] (2) Preparation of modified nano zinc oxide:

[0063] 1) Nano zinc oxide and hexadecyltrimethylammonium bromide were ultrasonically dispersed in deionized water at a mass ratio of 1:5. After uniform dispersion, the mixture was heated to 130℃ and reacted at a constant temperature for 5 hours. After centrifugation, the mixture was washed with ethanol and deionized water in sequence, dried under vacuum at 70℃ for 12 hours, and then ultrasonically dispersed in 1M hydrochloric acid solution. After ultrasonic treatment for 2 hours, the mixture was centrifuged, and the precipitate was collected and calcined at 500℃ for 3 hours to obtain mesoporous zinc oxide.

[0064] 2) Dissolve cerium nitrate in deionized water to form a cerium nitrate solution, adjust the pH to 6, and then add mesoporous zinc oxide to the cerium nitrate solution. The mass ratio of cerium nitrate to mesoporous zinc oxide is 1:30. After ultrasonic dispersion, stir at 300 r / min for 3 h, then add 20% sodium hydroxide solution dropwise to adjust the pH to 10. Continue stirring at room temperature for 4 h, then filter, wash with deionized water, and freeze-dry to obtain cerium-doped zinc oxide for later use.

[0065] 3) Cerium-doped zinc oxide was ultrasonically dispersed in glucose solution. After uniform dispersion, it was placed under ultraviolet light at 365 nm for 6 hours. During the illumination, it was stirred at a speed of 200 r / min. After completion, it was centrifuged, washed with ethanol, and vacuum dried at 60℃ for 8 hours. Then, it was calcined at 500℃ under nitrogen atmosphere for 2 hours. After that, air was introduced at a rate of 500 mL / min, and the temperature was raised to 600℃ for 1 hour.

[0066] (3) Add modified lignin and modified nano zinc oxide to a high-speed mixer at a mass ratio of 1:1 and mix at a speed of 1000 r / min for 20 min. Then add 3% stabilizer 770 and 3% antioxidant 1010 and mix evenly to obtain the anti-aging agent.

[0067] S2. The weighed α-olefin block copolymers were divided into α-olefin block copolymer I and α-olefin block copolymer II in a ratio of 2:8. α-olefin block copolymer I, the anti-aging agent, and the maleic anhydride graft were added sequentially to a high-speed mixer and stirred at 80°C and 600 r / min for 20 min. Then, the mixture was added to a ball mill, and anhydrous ethanol (solid-liquid ratio 1:3) was added. The mixture was then ground at 400 r / min for 3 h to obtain an anti-aging agent dispersion for later use.

[0068] S3. Mix PBS and EVOH and add them to deionized water at 90℃. Disperse by sonication for 40 min to form an aqueous suspension. Then add Span-80 and stir at 200 r / min for 30 min to obtain a polar phase aqueous suspension for later use.

[0069] The amount of deionized water added is 10 times the total mass of PBS and EVOH, and the amount of Span-80 added is 1% of the volume of the aqueous suspension.

[0070] S4. Add α-olefin block copolymer II, hyperbranched polyethylene, polar phase aqueous suspension, anti-aging agent dispersion, and DCP sequentially into a twin-screw extruder for extrusion granulation.

[0071] Comparative Example 1

[0072] Based on Example 2, in the preparation of the anti-aging agent, the modified lignin was replaced with untreated lignin, and the rest of the technical solutions were the same as in Example 2.

[0073] Comparative Example 2

[0074] Based on Example 2, in the preparation of the anti-aging agent, the modified nano zinc oxide was replaced with unmodified nano zinc oxide, and the rest of the technical solutions were the same as in Example 2.

[0075] Comparative Example 3

[0076] Based on Example 3, no modified nano zinc oxide was added in the preparation of the anti-aging agent, and the rest of the technical solutions were the same as in Example 2.

[0077] Comparative Example 4

[0078] A method for preparing an anti-aging TPE composite material includes the following steps:

[0079] S1. Weigh out the corresponding weight parts of 75 parts of α-olefin block copolymer, 40 parts of PBS, 12 parts of EVOH, 6 parts of hyperbranched polyethylene, 6 parts of anti-aging agent, 1.5 parts of DCP, and 4 parts of maleic anhydride graft for later use.

[0080] The preparation of the anti-aging agent includes the following steps:

[0081] (1) Add lignin to a 7% NaOH solution and stir at 55°C to form a lignin solution. Then add acrylate monomers containing hindered phenolic structures to the lignin solution. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:3.5. After stirring and mixing, add potassium persulfate. The mass ratio of the hindered phenolic acrylate monomers to lignin is 1:3.5. Heat to 75°C and react for 4.5 hours. After the reaction is complete, cool to room temperature, adjust the pH to neutral with hydrochloric acid, add ethanol to precipitate the product, filter, wash with ethanol, and dry at 65°C to constant weight to obtain modified lignin.

[0082] (2) Preparation of modified nano zinc oxide:

[0083] 1) Nano zinc oxide and hexadecyltrimethylammonium bromide were ultrasonically dispersed in deionized water at a mass ratio of 1:4. After uniform dispersion, the mixture was heated to 125℃ and reacted at a constant temperature for 4.5 h. After centrifugation, the mixture was washed successively with ethanol and deionized water, dried under vacuum at 65℃ for 11 h, and then ultrasonically dispersed in 1M hydrochloric acid solution. After ultrasonic treatment for 1.5 h, the mixture was centrifuged, and the precipitate was collected and calcined at 450℃ for 2.5 h to obtain mesoporous zinc oxide.

[0084] 2) Dissolve cerium nitrate in deionized water to form a cerium nitrate solution, adjust the pH to 6, and then add mesoporous zinc oxide to the cerium nitrate solution. The mass ratio of cerium nitrate to mesoporous zinc oxide is 1:20. After ultrasonic dispersion, stir at 250 r / min for 2.5 h, then add 15% sodium hydroxide solution dropwise to adjust the pH to 9. Continue stirring at room temperature for 3.5 h, filter, wash with deionized water, and freeze-dry to obtain cerium-doped zinc oxide for later use.

[0085] 3) Cerium-doped zinc oxide was ultrasonically dispersed in a glucose solution. After uniform dispersion, it was placed under ultraviolet light at 365 nm for 5.5 h. During the illumination, the mixture was stirred at 150 r / min. After centrifugation, the mixture was washed with ethanol and vacuum dried at 55 °C for 7 h. Then, it was calcined at 450 °C under a nitrogen atmosphere for 1.5 h. After that, air was introduced at a rate of 450 mL / min, and the temperature was raised to 550 °C for calcination for another 0.7 h.

[0086] (3) Add modified lignin and modified nano zinc oxide to a high-speed mixer at a mass ratio of 1:0.8 and mix at a speed of 900 r / min for 15 min. Then add 2% stabilizer 770 and 2% antioxidant 1010 and mix evenly to obtain the anti-aging agent.

[0087] S2. Weigh out the corresponding weight parts of α-olefin block copolymer, PBS, EVOH, hyperbranched polyethylene, anti-aging agent, DCP, and maleic anhydride graft and add them sequentially into a twin-screw extruder for extrusion granulation.

[0088] Performance testing

[0089] The thermoplastic elastomers obtained in the above embodiments and comparative examples were thermoplastically molded into 50mm×50mm samples with a thickness of 0.5mm, and then their performance was tested.

[0090] The tensile properties of the specimens were tested according to the method of GB / T 528-2009.

[0091] The test results are shown in Table 1 below.

[0092] Table 1. Tensile strength and elongation at break of the anti-aging TPE composite materials of each example and comparative example before aging treatment.

[0093]

[0094] As can be seen from Table 1 above, compared with the comparative example, the material prepared by the method of the present invention has high tensile strength and elongation at break, and excellent mechanical properties.

[0095] The above samples were placed in a thermal aging chamber and kept at 120°C for 120 hours. The tensile properties and hardness were tested again, and the retention rate was calculated. The results are shown in Table 2 below.

[0096] Table 2. Retention rate of tensile strength and elongation at break of anti-aging TPE composite materials after thermal aging in Example 2 and each comparative example.

[0097]

[0098] To further test the anti-aging properties of the anti-aging TPE composite material prepared by the method of this invention, the samples of each group were placed in an accelerated UV aging tester for 240 hours of UV aging. The UV lamp wavelength was 340 nm, the radiation intensity was 0.74 W / m², the relative humidity was 40%, and the test chamber temperature was 60 °C. Then, the tensile properties were tested. The test results are shown in Table 3 below.

[0099] Table 3. Retention rate of tensile strength and elongation at break of anti-aging TPE composite materials after UV aging in Example 2 and each comparative example.

[0100]

[0101] As can be seen from Tables 2 and 3 above, compared with Comparative Examples 1 to 4, the elastomer material of the sample in Example 2 still has high tensile strength and elongation at break after heat aging or UV aging treatment, and excellent anti-aging performance. Moreover, its performance is significantly better than that of the comparative examples, indicating that the preparation method provided by the present invention can significantly improve the anti-aging performance of TPE composite materials.

[0102] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An anti-aging TPE composite material, characterized in that, The composition comprises the following components in parts by weight: 60-90 parts of alpha-olefin block copolymer, 30-45 parts of polybutylene succinate, 8-15 parts of ethylene-vinyl alcohol copolymer, 5-8 parts of hyperbranched polyethylene, 4-8 parts of anti-aging agent, 1-2 parts of dicumyl peroxide, and 3-5 parts of maleic anhydride grafting product; The preparation method of the anti-aging agent is as follows: modified lignin and modified nano zinc oxide are added into a high-speed mixer at a mass ratio of 1:0.6-1, mixed at a rotating speed of 800-1000 r / min for 10-20 min, then light stabilizer 770 and antioxidant 1010 are added and uniformly mixed to obtain the anti-aging agent; The preparation method of the modified lignin is as follows: lignin is added into a NaOH solution with a mass fraction of 5-10%, stirred at 50-60°C to form a lignin solution, then an acrylic ester monomer containing a hindered phenol structure is added into the lignin solution, stirred and uniformly mixed, then potassium persulfate is added, the temperature is raised to 70-80°C, and reaction is carried out for 4-5 h, after the reaction is completed, the temperature is cooled to room temperature, the pH is adjusted to neutral with hydrochloric acid, then ethanol is added to precipitate the product, the product is filtered, washed with ethanol, and dried at a temperature of 60-70°C until the weight is constant to obtain the modified lignin; The preparation of the modified nano zinc oxide comprises the following steps: 1) nano zinc oxide and cetyltrimethylammonium bromide are ultrasonically dispersed into deionized water at a mass ratio of 1:3-5, uniformly dispersed, heated to 120-130°C, and reacted at constant temperature for 4-5 h, then centrifuged, washed with ethanol and deionized water in sequence, vacuum dried at 60-70°C for 10-12 h, ultrasonically dispersed into a 1M hydrochloric acid solution, ultrasonically treated for 1-2 h, centrifuged, the precipitate is collected, calcined at 400-500°C for 2-3 h to obtain mesoporous zinc oxide; 2) cerium nitrate is dissolved into deionized water to form a cerium nitrate solution, the pH is adjusted to 6, then the mesoporous zinc oxide is added into the cerium nitrate solution, ultrasonically dispersed, stirred at a rotating speed of 200-300 r / min for 2-3 h, then a sodium hydroxide solution is added to adjust the pH to 9-10, the stirring is continued at room temperature for 3-4 h, then filtered, washed with deionized water, and freeze-dried to obtain cerium-doped zinc oxide for standby use; 3) the cerium-doped zinc oxide is ultrasonically dispersed into a glucose solution, uniformly dispersed, placed under ultraviolet light at 365 nm, and irradiated for 5-6 h, while stirring at a rotating speed of 100-200 r / min, then centrifuged, washed with ethanol, vacuum dried at 50-60°C for 6-8 h, then calcined at 400-500°C in a nitrogen atmosphere for 1-2 h, then air is passed in at a speed of 400-500 mL / min, the temperature is raised to 500-600°C, and the calcination is continued for 0.5-1 h.

2. The anti-aging TPE composite material according to claim 1, characterized in that, The light stabilizer 770 and the antioxidant 1010 respectively account for 1-3% of the total mass of the modified lignin and the modified nano zinc oxide.

3. The anti-aging TPE composite material according to claim 2, characterized in that, The mass ratio of the acrylic ester monomer with a hindered phenol structure to the lignin is 1:2-5; The mass ratio of potassium persulfate to the acrylic ester monomer with a hindered phenol structure is 1:40-60.

4. The anti-aging TPE composite material according to claim 3, characterized in that, The mass ratio of cerium nitrate to mesoporous zinc oxide in step 2) is 1:10-30; The mass fraction of sodium hydroxide is 10-20%.

5. A method for the production of an anti-aging TPE composite according to any one of claims 1 to 4, characterized in that The method comprises the following steps: S1, weigh the corresponding weight parts of α-olefin block copolymer 60-90 parts, polybutylene succinate 30-45 parts, ethylene-vinyl alcohol copolymer 8-15 parts, hyperbranched polyethylene 5-8 parts, anti-aging agent 4-8 parts, dicumyl peroxide 1-2 parts, maleic anhydride grafting 3-5 parts for standby; S2, the weighed α-olefin block copolymer is divided into α-olefin block copolymer I and α-olefin block copolymer II according to the ratio of 2:8, and the α-olefin block copolymer I and the anti-aging agent, maleic anhydride grafting are added into the high-speed mixer in turn, and stirred and treated at 70-80℃ and 500-600r / min for 10-20min, then added into the ball mill, and then added with anhydrous ethanol, and ground at 300-400r / min for 2-3h to obtain an anti-aging agent dispersion liquid for standby; S3, the polybutylene succinate and ethylene-vinyl alcohol copolymer are mixed and then added into deionized water at 80-90℃, ultrasonic dispersion is performed for 30-40min to form a water suspension, then Span-80 is added, and stirring treatment is performed at 100-200r / min for 20-30min to obtain a polar phase water suspension for standby; S4, the α-olefin block copolymer II, hyperbranched polyethylene, polar phase water suspension, anti-aging agent dispersion liquid and dicumyl peroxide are added into a double-screw extruder in turn, and extrusion granulation is performed.

6. The method for preparing an anti-aging TPE composite material according to claim 5, characterized in that, The anhydrous ethanol in step S2 is added with a solid-liquid ratio of 1:2-3.

7. The method for preparing an anti-aging TPE composite material according to claim 6, characterized in that, The amount of deionized water added in step S3 is 6-10 times the total mass of polybutylene succinate and ethylene-vinyl alcohol copolymer, and the amount of Span-80 added is 0.6-1% of the volume of the water suspension.

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