An anti-aging polyolefin masterbatch and a method for preparing the same

Abstract

This invention discloses an anti-aging polyolefin masterbatch and its preparation method, comprising the following raw materials in parts by weight: 50-68 parts of acrylic resin, 10-20 parts of α-olefin ethylene copolymer, 4-9 parts of antioxidant, 3-8 parts of ultraviolet absorber, 2-6 parts of light stabilizer, 6-10 parts of modified montmorillonite powder, 8-12 parts of modified sericite powder, 4-8 parts of modified wollastonite powder, 3-8 parts of dispersant, and 2-5 parts of compatibilizer; the antioxidant includes at least hindered phenolic antioxidants. This anti-aging polyolefin masterbatch can improve the antioxidant properties, photothermal stability, and long-term storage stability of polyolefin masterbatches and plastic products, effectively inhibit yellowing, exhibit long-term stable anti-aging effects, and maintain the durability of the mechanical properties of polyolefin masterbatches and their plastic products.

Description

Technical Field

[0001] This invention relates to an anti-aging polyolefin masterbatch and its preparation method, belonging to the field of polyolefin material technology. Background Technology

[0002] Polyolefin masterbatches are high-concentration functional composite particles made by uniformly dispersing high-concentration functional additives in polyolefin resins such as polyethylene (PE) and polypropylene (PP) through a melt blending process. They are used in various fields including plastic products, automotive parts, electronics, and packaging materials. However, a major challenge faced by polyolefin materials in practical applications is aging. Aging leads to performance degradation, such as yellowing, brittleness, cracking, and decreased mechanical properties. This not only shortens the lifespan of polyolefin products but may also pose safety hazards, limiting their application in high-end fields. To address these issues, the development of polyolefin masterbatches incorporates various anti-aging technologies to maintain material stability. However, this requires considering problems such as uneven dispersion of anti-aging functional additives in the polyolefin masterbatch and poor compatibility between high-concentration anti-aging functional additives and the polyolefin matrix resin. Therefore, there is an urgent need to develop an anti-aging polyolefin masterbatch and its preparation method to improve the long-term stability of polyolefin masterbatches in terms of anti-aging properties. Summary of the Invention

[0003] To address at least one problem existing in the prior art, the present invention provides an anti-aging polyolefin masterbatch and its preparation method, which can improve the antioxidant properties, photothermal stability and long-term storage stability of the masterbatch and plastic products, effectively inhibit yellowing, have a long-term stable anti-aging effect, and maintain the durability of the mechanical properties of the polyolefin masterbatch and its plastic products.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an anti-aging polyolefin masterbatch, comprising the following raw materials in parts by weight: 50-68 parts of propylene resin, 10-20 parts of α-olefin ethylene copolymer, 4-9 parts of antioxidant, 3-8 parts of ultraviolet absorber, 2-6 parts of light stabilizer, 6-10 parts of modified montmorillonite powder, 8-12 parts of modified sericite powder, 4-8 parts of modified wollastonite powder, 3-8 parts of dispersant, and 2-5 parts of compatibilizer; The antioxidants include at least hindered phenolic antioxidants.

[0005] Preferably, the modified montmorillonite powder is obtained by first activating and pretreating nano-montmorillonite, and then adding quaternary ammonium salt organic modifiers and modifying it through intercalation treatment.

[0006] Preferably, the quaternary ammonium salt organic modifier is one of Gemini quaternary ammonium salt surfactant, octadecyltrimethylammonium bromide, or hexadecyltrimethylammonium bromide, with Gemini quaternary ammonium salt surfactant being the most preferred.

[0007] Preferably, the sericite powder is obtained by first expanding sericite with a particle size of 5~25μm, then adding a pyridine derivative intercalating agent for intercalation treatment, and then adding acrylate and azobisisobutyronitrile for in-situ polymerization modification.

[0008] Preferably, in sericite with a particle size of 5-25 μm, the weight of sericite with a particle size of 5-10 μm accounts for 35-45% of the weight of sericite with a particle size of 5-20 μm, and the weight of sericite with a particle size of 20-250 μm accounts for 15-20% of the weight of sericite with a particle size of 5-20 μm.

[0009] Preferably, the pyridine derivative intercalating agent is one of 4-vinylpyridine, dodecylpyridine chloride, hexadecylpyridine chloride, or hexadecylpyridine bromide, with 4-vinylpyridine being the most preferred.

[0010] Preferably, the modified wollastonite powder is obtained by modifying wollastonite with a particle size of 1~3μm with a silane coupling agent.

[0011] Preferably, the silane coupling agent is one of silane coupling agent KH-55 or silane coupling agent KH-560.

[0012] Preferably, the hindered phenolic antioxidant is a complex of antioxidant 1010, antioxidant 1076 or antioxidant 3324, etc., combined with antioxidant 264.

[0013] Preferably, in the hindered phenolic antioxidant, the mass ratio of one of the antioxidants 1010, 1076, or 3324 to antioxidant 264 is 2 to 3:1.

[0014] Preferably, the antioxidant further includes one or both of phosphite antioxidants and thioester antioxidants.

[0015] Preferably, the mass ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 4-5:1.

[0016] Preferably, the mass ratio of the hindered phenolic antioxidant to the thioester antioxidant is 3-4:1.

[0017] Preferably, the mass ratio of the hindered phenolic antioxidant to the phosphite antioxidant and the thioester antioxidant is 6~7:1.5:1.

[0018] Preferably, the phosphite antioxidant is antioxidant 168.

[0019] Preferably, the thioester antioxidant is the antioxidant DLTP.

[0020] Preferably, the dispersant comprises polyethylene wax and nano-silica.

[0021] Preferably, in the dispersant, the mass ratio of the polyethylene wax to nano-silica is 7~8:1.

[0022] Preferably, the compatibilizer comprises maleic anhydride-grafted polypropylene and ethylene-acrylate copolymer.

[0023] Preferably, in the compatibilizer, the mass ratio of the maleic anhydride-grafted polypropylene to the ethylene-acrylate copolymer is 1 to 2:1.

[0024] Preferably, the light stabilizer is one of light stabilizer HPT, light stabilizer GW-540, light stabilizer BW-10LD, light stabilizer 944, light stabilizer 791, etc.

[0025] Preferably, the ultraviolet absorber is one of ultraviolet absorber UV-531, ultraviolet absorber UVP-327, ultraviolet absorber UVP-326, ultraviolet absorber UV-360, etc.

[0026] This invention also provides a method for preparing anti-aging polyolefin masterbatch, comprising the following steps: Step 1: Add parts by weight of polypropylene, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, hindered amine light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer into a mixer and mix until uniform. Discharge to obtain the mixture. Step 2: The mixture is fed into a twin-screw extruder for mixing, extrusion, and granulation to obtain anti-aging polyolefin masterbatch.

[0027] Preferably, the temperature of the twin-screw extruder is 155~165℃ in zone one, 165~180℃ in zone two, 180~200℃ in zone three, 200~220℃ in zone four, and 170~190℃ in zone five.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The anti-aging polyolefin masterbatch provided by the present invention, through the synergistic effect of α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer, can significantly improve its antioxidant properties, photothermal stability and long-term storage stability, effectively inhibit yellowing, enable high-performance polypropylene materials to have long-term stable anti-aging effects, and maintain the durability of the mechanical properties of polyolefin masterbatch and its plastic products.

[0029] 2. This invention uses modified montmorillonite powder, modified sericite powder, and modified wollastonite powder to ensure good compatibility and uniform dispersion with polypropylene resin, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, and light stabilizer. Furthermore, these three components work synergistically with the antioxidant, ultraviolet absorber, and light stabilizer to improve the anti-aging properties of the polyolefin masterbatch, resulting in plastic products made from the polyolefin masterbatch material having a longer service life.

[0030] 3. The modified montmorillonite powder used in this invention can also avoid the accumulation of static electricity in polyolefin masterbatch during use, thereby improving the quality of polyolefin masterbatch and its plastic products. Detailed Implementation

[0031] The following is a clear and complete description of the technical solutions in the implementation of this invention. The described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents, instruments, or components used that do not specify the manufacturer are all conventional products that can be purchased commercially.

[0032] Preparation Example 1: Preparation of a Modified Montmorillonite Powder The preparation process of modified montmorillonite is as follows: First, nano-montmorillonite with a particle size of 100~200nm is soaked in 12% hydrochloric acid for activation. The amount of 12% hydrochloric acid is 1.8 times the weight of the nano-montmorillonite. The mixture is heated to 55~60℃ and activated for 1.5h. The liquid is removed by centrifugation and washed with water until neutral. Then, the activated nano-montmorillonite is added to water and sodium silicate and stirred to disperse evenly, forming a nano-montmorillonite slurry with a mass fraction of 5% and a sodium silicate content of 0.1% of the nano-montmorillonite weight. The montmorillonite slurry is heated to 45~50℃ and stirred. Quaternary ammonium salt organic modifier is added, with the amount of quaternary ammonium salt organic modifier being 50% of the weight of the nano-montmorillonite. The mixture is stirred for 60min to allow the quaternary ammonium salt organic modifier to fully react with the montmorillonite. The liquid is removed by centrifugation, washed with water, and dried to obtain modified montmorillonite powder.

[0033] The quaternary ammonium salt organic modifier used in this preparation example is Gemini quaternary ammonium salt surfactant. The quaternary ammonium salt organic modifier can also be one of octadecyltrimethylammonium bromide or hexadecyltrimethylammonium bromide.

[0034] Preparation Example 2: Preparation of a Modified Sericite Powder The preparation process of modified sericite powder is as follows: sericite particles with a diameter of 5-25 μm are soaked in 30% hydrogen peroxide solution at pH 5 for expansion. The amount of 30% hydrogen peroxide is twice the amount of sericite. The mixture is stirred and heated to 75-80℃ for 75 minutes. The weight of sericite particles with a diameter of 5-10 μm accounts for 40% of the total weight of sericite particles with a diameter of 5-20 μm, and the weight of sericite particles with a diameter of 20-250 μm accounts for 18% of the total weight of sericite particles with a diameter of 5-20 μm. The mixture is then filtered and washed with water. Then, the expanded sericite is mixed with a 25% ethanol aqueous solution and heated to 35-40°C. A pyridine derivative intercalating agent is added and stirred for 50 minutes. The amount of the pyridine derivative intercalating agent is 10% of the weight of the sericite. Then, acrylate and azobisisobutyronitrile are added and heated to 65-70°C. The in-situ polymerization reaction is stirred for 2.5 hours. The amount of acrylate is 12% of the weight of the sericite and the amount of azobisisobutyronitrile is 2.5% of the weight of the acrylate. The mixture is filtered, washed with water, and dried to obtain modified sericite powder.

[0035] The pyridine derivative intercalating agent in this preparation example is 4-vinylpyridine; the pyridine derivative intercalating agent can also be selected from one of dodecylpyridine chloride, hexadecylpyridine chloride, or hexadecylpyridine bromide.

[0036] Preparation Example 3: Preparation of a Modified Wollastonite Powder The preparation process of modified wollastonite powder is as follows: Wollastonite with a particle size of 1~3μm is mixed with water and ultrasonically dispersed to form a wollastonite slurry with a mass fraction of 38%. A silane coupling agent is mixed with a 25% ethanol aqueous solution to form a silane coupling agent solution with a mass fraction of 8%. Under stirring conditions, the silane coupling agent solution is added to the wollastonite slurry, heated to 65~70℃, and reacted for 25~30min. The amount of silane coupling agent used is 0.8% of the weight of wollastonite. The mixture is filtered, washed with water, and dried to obtain modified wollastonite powder.

[0037] The silane coupling agent used in this preparation example is silane coupling agent KH-550; silane coupling agent KH-560 can also be selected.

[0038] Example 1 An anti-aging polyolefin masterbatch comprises the following raw materials in parts by weight: 50 parts of acrylic resin, 10 parts of α-olefin ethylene copolymer, 4 parts of antioxidant, 3 parts of ultraviolet absorber UV-327, 2 parts of light stabilizer HPT, 6 parts of modified montmorillonite powder of Preparation Example 1, 8 parts of modified sericite powder of Preparation Example 2, 4 parts of modified wollastonite powder of Preparation Example 3, 3 parts of dispersant, and 2 parts of compatibilizer.

[0039] The antioxidant is a hindered phenolic antioxidant, which is a complex of antioxidant 1010 and antioxidant 264, with a mass ratio of antioxidant 1010 to antioxidant 264 of 2.5:1; the dispersant is composed of polyethylene wax and nano silica, with a mass ratio of polyethylene wax to nano silica of 7:1; the compatibilizer is composed of maleic anhydride-grafted polypropylene and ethylene-acrylate copolymer, with a mass ratio of maleic anhydride-grafted polypropylene to ethylene-acrylate copolymer of 1:1. The preparation process of the anti-aging polyolefin masterbatch is as follows: Step 1: Add the above-mentioned parts by weight of polypropylene, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, hindered amine light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer into a mixer and mix. Stir at 1200 rpm for 3.5 hours, and discharge to obtain the mixture. Step 2: The mixture is fed into a twin-screw extruder for mixing, extrusion, and granulation. The temperature of the twin-screw extruder is 155℃ in zone 1, 165℃ in zone 2, 180℃ in zone 3, 200℃ in zone 4, and 170℃ in zone 5 to obtain anti-aging polyolefin masterbatch.

[0040] Example 2 An anti-aging polyolefin masterbatch comprises the following raw materials in parts by weight: 58 parts of acrylic resin, 14 parts of α-olefin ethylene copolymer, 6 parts of antioxidant, 5 parts of ultraviolet absorber UV-531, 4.5 parts of light stabilizer GW-540, 8 parts of modified montmorillonite powder of Preparation Example 1, 10 parts of modified sericite powder of Preparation Example 2, 6 parts of modified wollastonite powder of Preparation Example 3, 5 parts of dispersant, and 3.5 parts of compatibilizer; The antioxidant is a complex of antioxidant 3324 and antioxidant 264, with a mass ratio of 2:1. The dispersant is composed of polyethylene wax and nano-silica, with a mass ratio of 8:1. The compatibilizer is composed of maleic anhydride-grafted polypropylene and ethylene-acrylate copolymer, with a mass ratio of 1.5:1. The preparation process of the anti-aging polyolefin masterbatch is as follows: Step 1: Add the above-mentioned parts by weight of polypropylene, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, hindered amine light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer into a mixer and mix. Stir at 1100 rpm for 3 hours, and discharge to obtain the mixture. Step 2: The mixture is fed into a twin-screw extruder for mixing, extrusion, and granulation. The temperature of the twin-screw extruder is 160℃ in zone 1, 178℃ in zone 2, 190℃ in zone 3, 210℃ in zone 4, and 180℃ in zone 5 to obtain anti-aging polyolefin masterbatch.

[0041] Example 3 An anti-aging polyolefin masterbatch comprises the following raw materials in parts by weight: 68 parts of acrylic resin, 20 parts of α-olefin ethylene copolymer, 9 parts of antioxidant, 8 parts of ultraviolet absorber UV-360, 6 parts of light stabilizer 791, 10 parts of modified montmorillonite powder of Preparation Example 1, 12 parts of modified sericite powder of Preparation Example 2, 8 parts of modified wollastonite powder of Preparation Example 3, 8 parts of dispersant, and 5 parts of compatibilizer; The antioxidant is a complex of antioxidant 1076 and antioxidant 264, with a mass ratio of 3:1; the dispersant is a composite of polyethylene wax and nano-silica, with a mass ratio of 7.5:1; the compatibilizer is a composite of maleic anhydride-grafted polypropylene and ethylene-acrylate copolymer, with a mass ratio of 2:1. The preparation process of the anti-aging polyolefin masterbatch is as follows: Step 1: Add the above-mentioned parts by weight of polypropylene, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, hindered amine light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer into a mixer and mix. Stir at 1000 rpm for 4 hours, and discharge to obtain the mixture. Step 2: The mixture is fed into a twin-screw extruder for mixing, extrusion, and granulation. The temperature of the twin-screw extruder is 165℃ in zone 1, 180℃ in zone 2, 200℃ in zone 3, 220℃ in zone 4, and 190℃ in zone 5 to obtain anti-aging polyolefin masterbatch.

[0042] Example 4 An anti-aging polyolefin masterbatch differs from Example 1 in that: the ultraviolet absorber is 3 parts of ultraviolet absorber UV-531 and the light stabilizer is 2 parts of light stabilizer HPT.

[0043] Example 5 An anti-aging polyolefin masterbatch differs from Example 3 in that: the antioxidant includes hindered phenolic antioxidant and antioxidant 168, with a mass ratio of hindered phenolic antioxidant to antioxidant 168 of 5:1; the hindered phenolic antioxidant is a complex of antioxidant 3324 and antioxidant 264, with a mass ratio of antioxidant 3324 to antioxidant 264 of 2:1.

[0044] Example 6 An anti-aging polyolefin masterbatch differs from Example 3 in that: the antioxidant includes hindered phenolic antioxidant and antioxidant DLTP, with a mass ratio of hindered phenolic antioxidant to antioxidant DLTP of 4:1; the hindered phenolic antioxidant is a complex of antioxidant 3324 and antioxidant 264, with a mass ratio of antioxidant 3324 to antioxidant 264 of 2:1.

[0045] Example 7 An anti-aging polyolefin masterbatch differs from Example 3 in that: the antioxidants include hindered phenolic antioxidants, antioxidant 168, and antioxidant DLTP, with the mass ratio of hindered phenolic antioxidants to antioxidant 168 and antioxidant DLTP being 6.5:1.5:1; the hindered phenolic antioxidant is a complex of antioxidant 3324 and antioxidant 264, with the mass ratio of antioxidant 3324 to antioxidant 264 being 2:1.

[0046] Example 8 An anti-aging polyolefin masterbatch differs from Example 2 in that: in the modified sericite powder, the weight of sericite with a particle size of 5-25 μm accounts for 35% of the weight of sericite with a particle size of 5-10 μm, and the weight of sericite with a particle size of 20-250 μm accounts for 15% of the weight of sericite with a particle size of 5-20 μm.

[0047] Example 9 An anti-aging polyolefin masterbatch differs from Example 2 in that: in the modified sericite powder, the sericite with a particle size of 5-25 μm accounts for 45% of the weight of the sericite with a particle size of 5-10 μm, and the sericite with a particle size of 20-250 μm accounts for 20% of the weight of the sericite with a particle size of 5-20 μm.

[0048] Example 10 An anti-aging polyolefin masterbatch differs from Example 2 in that: in the modified sericite powder, the sericite with a particle size of 5-25 μm accounts for 60% of the weight of the sericite with a particle size of 5-10 μm, and the sericite with a particle size of 20-250 μm accounts for 10% of the weight of the sericite with a particle size of 5-20 μm.

[0049] Example 11 An anti-aging polyolefin masterbatch differs from Example 2 in that: in the modified sericite powder, the weight of sericite with a particle size of 5-25 μm accounts for 25% of the weight of sericite with a particle size of 5-10 μm, and the weight of sericite with a particle size of 20-250 μm accounts for 35% of the weight of sericite with a particle size of 5-20 μm.

[0050] Example 12 An anti-aging polyolefin masterbatch differs from Example 2 in that the modified sericite powder is obtained by modifying sericite with a particle size of 5-25 μm using silane coupling agent KH-550 according to the preparation steps of Preparation 3; wherein, the weight of sericite with a particle size of 5-10 μm accounts for 40% of the weight of sericite with a particle size of 5-20 μm, and the weight of sericite with a particle size of 20-250 μm accounts for 18% of the weight of sericite with a particle size of 5-20 μm.

[0051] Example 13 An anti-aging polyolefin masterbatch differs from Example 2 in that the modified montmorillonite powder is obtained by modifying nano-montmorillonite with a particle size of 100~200nm with silane coupling agent KH-550 according to the preparation steps of Preparation 3.

[0052] Example 14 An anti-aging polyolefin masterbatch, which differs from Example 2 in that maleic anhydride-grafted polypropylene is omitted.

[0053] Example 15 An anti-aging polyolefin masterbatch, which differs from Example 2 in that the ethylene-acrylate copolymer is omitted.

[0054] Example 16 An anti-aging polyolefin masterbatch, which differs from Example 2 in that nano-silica is omitted.

[0055] Example 17 An anti-aging polyolefin masterbatch, which differs from Example 2 in that calcium stearate is used instead of polyethylene wax.

[0056] Comparative Example 1 An anti-aging polyolefin masterbatch differs from Example 2 in that nano-montmorillonite with a particle size of 100~200nm replaces modified montmorillonite powder.

[0057] Comparative Example 2 An anti-aging polyolefin masterbatch differs from Example 2 in that: sericite with a particle size of 5-25 μm replaces modified sericite powder; wherein, the weight of sericite with a particle size of 5-10 μm accounts for 40% of the weight of sericite with a particle size of 5-20 μm, and the weight of sericite with a particle size of 20-250 μm accounts for 18% of the weight of sericite with a particle size of 5-20 μm.

[0058] Comparative Example 3 An anti-aging polyolefin masterbatch differs from Example 2 in that wollastonite with a particle size of 1~3μm is used instead of modified wollastonite powder.

[0059] Comparative Example 4 An anti-aging polyolefin masterbatch, which differs from Example 2 in that: the modified montmorillonite powder is 0 parts.

[0060] Comparative Example 5 An anti-aging polyolefin masterbatch, which differs from Example 2 in that: the modified sericite powder is 0 parts.

[0061] Comparative Example 6 An anti-aging polyolefin masterbatch differs from Example 2 in that the modified wollastonite powder is 0 parts.

[0062] Comparative Example 7 An anti-aging polyolefin masterbatch, which differs from Example 2 in that it contains only antioxidant 3324.

[0063] Comparative Example 8 An anti-aging polyolefin masterbatch differs from Example 2 in that the antioxidants are antioxidant 246 and antioxidant 168, and the mass ratio of antioxidant 246 to antioxidant 168 is 2:1.

[0064] Comparative Example 9 An anti-aging polyolefin masterbatch, which differs from Example 2 in that the antioxidant is antioxidant 168.

[0065] Comparative Example 10 An anti-aging polyolefin masterbatch, which differs from Example 2 in that the antioxidant is DLTP.

[0066] Comparative Example 11 An anti-aging polyolefin masterbatch differs from Example 2 in that: the ultraviolet absorber is 0 parts; and the light stabilizer is light stabilizer GW-540.

[0067] Comparative Example 12 An anti-aging polyolefin masterbatch, which differs from Example 2 in that: the ultraviolet absorber is ultraviolet absorber UVP-327; and there are 0 parts of light stabilizer.

[0068] Comparative Example 13 An anti-aging polyolefin masterbatch differs from Example 2 in that modified silicon nitride whiskers replace modified sericite powder; the modified silicon nitride whiskers are obtained by modifying silicon nitride whiskers with silane coupling agent KH-550 according to the preparation steps of preparation 3.

[0069] Comparative Example 14 An anti-aging polyolefin masterbatch differs from Example 2 in that modified silicon nitride whiskers replace modified montmorillonite powder; the modified silicon nitride whiskers are obtained by modifying silicon nitride whiskers with silane coupling agent KH-550 according to the preparation steps of preparation 3.

[0070] Comparative Example 15 An anti-aging polyolefin masterbatch differs from Example 2 in that modified talc powder replaces modified sericite powder; the modified talc powder is obtained by modifying silicon nitride whiskers with silane coupling agent KH-550 according to the preparation steps of preparation 3.

[0071] Example 1: Thermal aging test Tensile strength and elongation at break retention rate (%), yellowing index change (ΔYI), and appearance (cracking, powdering, etc.) after air aging: The anti-aging polyolefin masterbatches prepared in Examples 1-17 and Comparative Examples 1-15 were added to polypropylene resin at a mass fraction of 5%. After uniform mixing and dispersion, the samples were pressed into thin sheets of about 1 mm using a two-roll mill. The samples were tested using an air heat aging test chamber at 100℃ / 1200h, according to GB / T 7141-2008. The changes in tensile strength, elongation at break, yellowing index, and appearance (cracking, powdering, etc.) before and after aging were compared, and the results are shown in Table 1.

[0072] Table 1. Resistance to thermal aging

[0073] Example 2: Photoaging Test Tensile strength and elongation at break retention rate (%), yellowing index change (ΔYI), and appearance (cracking, powdering, etc.) after photoaging: The anti-aging polyolefin masterbatches prepared in Examples 1-17 and Comparative Examples 1-15 were added to polypropylene resin at a mass fraction of 5%. After uniform mixing and dispersion, the samples were pressed into thin sheets of approximately 1 mm using a two-roll mill. The samples were subjected to UVA-340 ultraviolet lamp irradiance of 0.76 W / m at 340 nm. 2 The sample was aged for 2500 hours at 50℃ and nm using the test method GB / T 14522-2008. The changes in tensile strength, elongation at break, yellowing index, and appearance (cracking, powdering, etc.) before and after aging were compared, and the results are shown in Table 2.

[0074] Table 2 Photothermal aging effect

[0075] As shown in Tables 1 and 2 above, the anti-aging polypropylene masterbatch of the present invention, using modified montmorillonite powder, modified sericite powder, and modified wollastonite powder, forms a synergistic effect with antioxidants, ultraviolet absorbers, and light stabilizers. It exhibits good compatibility and uniform dispersion in the base resin. By controlling the type of antioxidant used, it can significantly improve the antioxidant properties and photothermal stability of its plastic products, providing excellent anti-aging effects, effectively inhibiting yellowing, and maintaining the durability of the mechanical properties of plastic products prepared from polyolefin masterbatch. In Comparative Examples 1-16, changes in any component of the modified montmorillonite powder, modified sericite powder, modified wollastonite powder, antioxidant, ultraviolet absorber, and light stabilizer resulted in a decrease in the anti-aging effect of the plastic products prepared from the anti-aging polypropylene masterbatch, a significant increase in the yellowing index, and a weaker ability to inhibit yellowing.

[0076] Example 3: Antistatic Test Antistatic test: The anti-aging polyolefin masterbatches prepared in Examples 2 and 13 and Comparative Examples 1, 4-6 and 13-15 were added to polypropylene resin at a mass fraction of 5%. After uniform mixing and dispersion, the samples were pressed into thin sheets of about 1 mm using a two-roll mill. The surface resistance of the samples was tested according to GB / T1410-2006, and the results are shown in Table 3.

[0077] Table 3 Antistatic effect

[0078] As shown in Table 3 above, the anti-aging polypropylene masterbatch of the present invention has a good antistatic effect. Compared with Comparative Example 4, the addition of modified montmorillonite powder significantly avoids the accumulation of static electricity in the polyolefin masterbatch during use, significantly improves the antistatic effect of plastic products prepared using polyolefin masterbatch, and is beneficial to the processing of polyolefin masterbatch and its plastic products, thereby improving the quality of polyolefin masterbatch and its plastic products.

[0079] In summary, the anti-aging polypropylene masterbatch of this invention improves its antioxidant properties, photothermal stability, and long-term storage stability, effectively inhibits yellowing, and is applied to the preparation of high-performance polypropylene materials, giving high-performance polypropylene materials long-term stable anti-aging effects, and maintaining the durability of the mechanical properties of polyolefin masterbatches and their plastic products.

[0080] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit and essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0081] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An anti-aging polyolefin masterbatch, characterized in that, The raw materials include the following parts by weight: 50-68 parts of acrylic resin, 10-20 parts of α-olefin ethylene copolymer, 4-9 parts of antioxidant, 3-8 parts of ultraviolet absorber, 2-6 parts of light stabilizer, 6-10 parts of modified montmorillonite powder, 8-12 parts of modified sericite powder, 4-8 parts of modified wollastonite powder, 3-8 parts of dispersant, and 2-5 parts of compatibilizer; The antioxidants include at least hindered phenolic antioxidants.

2. The anti-aging polyolefin masterbatch according to claim 1, characterized in that, The hindered phenolic antioxidant is a complex of antioxidant 1010, antioxidant 1076 or antioxidant 3324 combined with antioxidant 264.

3. The anti-aging polyolefin masterbatch according to claim 1, characterized in that, The modified montmorillonite powder is obtained by first activating and pretreating nano-montmorillonite, and then adding quaternary ammonium salt organic modifiers and modifying it through intercalation treatment; The quaternary ammonium salt organic modifier is one of Gemini quaternary ammonium salt surfactant, octadecyltrimethylammonium bromide, or hexadecyltrimethylammonium bromide.

4. The anti-aging polyolefin masterbatch according to claim 1, characterized in that, The sericite powder is obtained by first expanding sericite with a particle size of 5~25μm, then adding pyridine derivative intercalating agent for intercalation treatment, and then adding acrylate and azobisisobutyronitrile for in-situ polymerization modification. The pyridine derivative intercalating agent is one of 4-vinylpyridine, dodecylpyridine chloride, hexadecylpyridine chloride, or hexadecylpyridine bromide.

5. The anti-aging polyolefin masterbatch according to claim 4, characterized in that, In the sericite with a particle size of 5-25 μm, the sericite with a particle size of 5-10 μm accounts for 35-45% of the total weight of the sericite with a particle size of 5-20 μm, and the sericite with a particle size of 20-250 μm accounts for 15-20% of the total weight of the sericite with a particle size of 5-20 μm.

6. The anti-aging polyolefin masterbatch according to claim 1, characterized in that, The modified wollastonite powder is obtained by modifying wollastonite with a particle size of 1~3μm with a silane coupling agent; The silane coupling agent is either silane coupling agent KH-55 or silane coupling agent KH-560.

7. The anti-aging polyolefin masterbatch according to claim 1 or 2, characterized in that, The antioxidants also include one or both of phosphite antioxidants and thioester antioxidants.

8. The anti-aging polyolefin masterbatch according to claim 1, characterized in that... The dispersant comprises polyethylene wax and nano-silica; The compatibilizer comprises maleic anhydride-grafted polypropylene and ethylene-acrylate copolymer.

9. The anti-aging polyolefin masterbatch according to claim 1, characterized in that, The light stabilizer is one of the following: light stabilizer HPT, light stabilizer GW-540, light stabilizer BW-10LD, light stabilizer 944, or light stabilizer 791. The ultraviolet absorber is one of ultraviolet absorber UV-531, ultraviolet absorber UVP-327, ultraviolet absorber UVP-326, and ultraviolet absorber UV-360.

10. A method for preparing an anti-aging polyolefin masterbatch as described in claim 1, characterized in that, Includes the following steps: Step 1: Add parts by weight of polypropylene, α-olefin ethylene copolymer, antioxidant, ultraviolet absorber, hindered amine light stabilizer, modified montmorillonite powder, modified sericite powder, modified wollastonite powder, dispersant and compatibilizer into a mixer and mix until uniform. Discharge to obtain the mixture. Step 2: The mixture is fed into a twin-screw extruder for mixing, extrusion, and granulation to obtain anti-aging polyolefin masterbatch.

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