Environment-friendly long-wearing antistatic PVC granules and preparation method thereof

Abstract

This invention provides an environmentally friendly, wear-resistant, long-lasting antistatic PVC granule and its preparation method. Through the innovative design of an "ionic liquid-MXene / carbon nanotube three-dimensional conductive network" structure synergistically combined with a "nano-alumina-silicone core-shell wear-resistant reinforcement system," and with the environmentally friendly combination of bio-based plasticizers and rare earth stabilizers, a breakthrough balance between antistatic durability and wear resistance is achieved. Specifically, the MXene hybrid inhibits interlayer stacking through ionic liquid bonding and forms a point-to-surface conductive pathway with the PEG-grafted carbon nanotubes, stabilizing the surface resistivity at 3.5 × 10⁻⁶. 7 -2.1×10 8 Ω; In-situ coating of nano-alumina with silicone resin reduces Taber wear while maintaining high elongation at break; Gradient mixing process combined with two-stage exhaust granulation reduces VOC emissions and dispersed phase particle size ≤200nm, solving the technical pain point of performance degradation and environmental protection contradiction in traditional processes.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, and in particular to a method for preparing environmentally friendly, wear-resistant, long-lasting, antistatic PVC granules. Background Technology

[0002] Polyvinyl chloride (PVC), as one of the five major general-purpose plastics, is widely used in construction, electronics, packaging, and other fields due to its excellent mechanical properties, chemical resistance, and low cost. However, traditional PVC materials face two major technical bottlenecks in specific applications: firstly, its high insulation properties result in a surface resistivity exceeding 10 Ω·cm. 12 Ω, which easily accumulates static charge, causing fires or damage to electronic components; secondly, its low hardness leads to insufficient wear resistance, resulting in a service life of less than 2 years in high-frequency friction scenarios such as conveyor belts and floors.

[0003] Currently, the industry mainly uses three technical solutions to improve the above problems:

[0004] 1. Adding small molecule antistatic agents (such as quaternary ammonium salts): Although it can reduce the surface resistance to 10 in the short term. 9 Ω, but there is a serious migration and precipitation phenomenon, which will reduce the hardness of the material;

[0005] 2. Blended conductive fillers (such as carbon black): Although they can achieve long-lasting antistatic properties, the amount added must be >15 phr, which will greatly increase the brittleness of the material and limit the color of the product.

[0006] 3. Physically reinforced wear resistance (such as adding glass fiber): Although it can improve wear resistance, it will destroy the antistatic pathway and cause excessive VOCs release during processing.

[0007] Furthermore, phthalate plasticizers are commonly used in existing technologies to balance processing flowability; however, they are classified as SVHC substances by regulations, posing a risk of reproductive toxicity. Additionally, the heavy metal residues produced by the decomposition of traditional lead salt stabilizers during high-temperature processing further restrict the environmental friendliness of the products.

[0008] Therefore, developing a PVC composite material that combines long-lasting antistatic properties, high wear resistance, environmental friendliness, and stable performance has become a pressing technical challenge in the field of polymer materials. Summary of the Invention

[0009] The purpose of this invention is to provide an environmentally friendly, wear-resistant, long-lasting, antistatic PVC granule and its preparation method, so as to solve the problems existing in the prior art.

[0010] To achieve the above objectives, the present invention provides the following solution:

[0011] This invention provides an environmentally friendly, wear-resistant, long-lasting, antistatic PVC granule, comprising, by weight: 55-65 parts PVC resin, 3-5 parts ionic liquid modified MXene hybrid, 12-18 parts nano-alumina / silicone composite wear-resistant agent, 8-12 parts bio-based plasticizer, 2.5-3.5 parts rare earth composite heat stabilizer, 1-2 parts surface-functionalized carbon nanotubes, 0.8-1.5 parts coupling agent, and 1.2-1.8 parts lubricant.

[0012] Preferably, the ionic liquid-modified MXene hybrid is composed of Ti3C2T X The MXene material was prepared by reacting it with [BMIM]PF6 ionic liquid at a mass ratio of 5:1.

[0013] Preferably, the nano-alumina / silicone composite wear-resistant agent has a core-shell structure formed by coating silicone resin with nano-α-Al2O3 particles, wherein the particle size of the nano-α-Al2O3 particles is 50 nm, and the amount of silicone resin coating is 10% of the mass of the nano-α-Al2O3 particles.

[0014] Preferably, the bio-based plasticizer is a compound of epoxidized soybean oil and citrate in a mass ratio of 6:4.

[0015] Preferably, the rare earth composite heat stabilizer is composed of a lanthanum / cerium organic complex and zinc soap mixed in a mass ratio of 3:1.

[0016] Preferably, the surface-functionalized carbon nanotubes are carboxylated multi-walled carbon nanotubes with polyethylene glycol molecular chains grafted onto their surface at a grafting rate of 8-12 wt%.

[0017] This invention also provides a method for preparing environmentally friendly, wear-resistant, long-lasting antistatic PVC granules, comprising the following steps:

[0018] S1. Preparation of ionic liquid-modified MXene hybrids, using Ti3C2T X MXene material was dispersed in anhydrous ethanol to obtain a solid-liquid mixture with a solid content of 5%. The mixture was ultrasonically treated at 40 kHz for 30 min, and then Ti3C2T was added. X 20% by weight of [BMIM]PF6 ionic liquid was reacted at 70°C for 2 hours, and then centrifuged and dried to obtain ionic liquid modified MXene hybrid for later use.

[0019] S2. To prepare a nano-alumina / silicone composite wear-resistant agent, nano-α-Al2O3 particles were stirred at 800 rpm in a high-speed mixer under heating conditions of 80℃, and silicone resin was sprayed in. The amount of silicone resin added was 10% of the mass of nano-α-Al2O3 particles. The reaction was carried out for 15 min to obtain the nano-alumina / silicone composite wear-resistant agent for later use.

[0020] S3. Gradient mixing and granulation: Using a co-rotating twin-screw extruder, PVC resin, some bio-based plasticizer, coupling agent, nano alumina / silicone composite wear-resistant agent, ionic liquid modified MXene hybrid, surface functionalized carbon nanotubes, remaining bio-based plasticizer, rare earth composite heat stabilizer and lubricant are added in sequence, and then extruded through the die after homogenization.

[0021] S4. Two-stage venting granulation: the first stage involves vacuum venting through a die at a pressure of -0.08 MPa; the second stage involves underwater pelletizing at a water temperature of 35-45℃; and the pellets are dried in a 60℃ fluidized bed until the moisture content is ≤0.1%, producing environmentally friendly, wear-resistant, long-lasting, antistatic PVC granules.

[0022] Preferably, step S3 specifically includes:

[0023] S31. Add PVC resin and 1 / 3 of the total mass of bio-based plasticizer to a co-rotating twin-screw extruder and pre-plasticize at 130°C for 5 minutes;

[0024] S32. Add nano-alumina / silicone composite wear-resistant agent and coupling agent, and mix at 145℃ for 3 minutes;

[0025] S33. Add ionic liquid-modified MXene hybrid, surface-functionalized carbon nanotubes and the remaining bio-based plasticizer, and mix at 155°C for 8 minutes.

[0026] S34. Add rare earth composite heat stabilizer and lubricant, homogenize at 150℃, and then extrude at 145℃ through a die.

[0027] Preferably, the rotational speed of the co-rotating twin-screw extruder is 250-300 rpm, and the temperature gradients of each zone are: 130°C in the feeding zone, 145°C in the melting zone, 155°C in the dispersing zone, 150°C in the homogenizing zone, and 145°C in the die.

[0028] Preferably, in step S4, the particle size of the underwater pelletizer is 3mm×3mm, and the exhaust gas is treated by activated carbon adsorption and catalytic combustion device after pelletizing.

[0029] The present invention achieves the following beneficial technical effects compared to the prior art:

[0030] This invention provides an environmentally friendly, wear-resistant, long-lasting antistatic PVC granule and its preparation method. Through the innovative design of an "ionic liquid-MXene / carbon nanotube three-dimensional conductive network" structure synergistically combined with a "nano-alumina-silicone core-shell wear-resistant reinforcement system," and with the environmentally friendly combination of bio-based plasticizers and rare earth stabilizers, a breakthrough balance between antistatic durability and wear resistance is achieved. Specifically, the MXene hybrid inhibits interlayer stacking through ionic liquid bonding and forms a point-to-surface conductive pathway with the PEG-grafted carbon nanotubes, stabilizing the surface resistivity at 3.5 × 10⁻⁶. 7 -2.1×10 8 Ω; In-situ coating of nano-alumina with silicone resin reduces Taber wear while maintaining high elongation at break; Gradient mixing process combined with two-stage exhaust granulation reduces VOC emissions and dispersed phase particle size ≤200nm, solving the technical pain point of performance degradation and environmental protection contradiction in traditional processes. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] The purpose of this invention is to provide an environmentally friendly, wear-resistant, long-lasting, antistatic PVC granule, comprising, by weight: 55-65 parts PVC resin, 3-5 parts ionic liquid modified MXene hybrid, 12-18 parts nano-alumina / silicone composite wear-resistant agent, 8-12 parts bio-based plasticizer, 2.5-3.5 parts rare earth composite heat stabilizer, 1-2 parts surface-functionalized carbon nanotubes, 0.8-1.5 parts coupling agent, and 1.2-1.8 parts lubricant.

[0033] The environmentally friendly, wear-resistant, long-lasting antistatic PVC granules provided by this invention adopt an "ionic liquid-MXene / carbon nanotube three-dimensional conductive network" structure in conjunction with a "nano-alumina-silicone core-shell wear-resistant reinforcement system". With the environmentally friendly combination of bio-based plasticizers and rare earth stabilizers, a breakthrough balance between antistatic durability and wear resistance is achieved.

[0034] Among them, SG-5 is used as the matrix material for PVC resin, and high degree of polymerization (>1300) resin is selected to improve mechanical strength and form an interpenetrating network with reinforcing fillers;

[0035] Ionic liquid-modified MXene hybrid as the core antistatic agent, composed of Ti3C2T XThe MXene material was prepared by reacting it with [BMIM]PF6 ionic liquid at a mass ratio of 5:1. MXene provides a conductive pathway, and grafting with [BMIM]PF6 ionic liquid improves dispersibility and longevity, forming a three-dimensional conductive network that inhibits charge accumulation.

[0036] The nano-alumina / silicone composite wear-resistant agent serves as the wear-resistant main body. It consists of a core-shell structure formed by nano-α-Al2O3 particles coated with silicone resin. The nano-α-Al2O3 particles have a particle size of 50nm, and the silicone resin coating amount is 10% of the mass of the nano-α-Al2O3 particles. The nano-α-Al2O3 provides hardness, the silicone resin improves toughness, and the silicone coating of alumina reduces agglomeration, thus synergistically improving wear resistance.

[0037] Bio-based plasticizers are used for environmentally friendly plasticizing. They use epoxidized soybean oil and citrate esters to replace DOP, reducing migration and enhancing compatibility with antistatic agents.

[0038] Rare earth composite heat stabilizer plays an environmentally friendly and stable role. It is made by mixing lanthanum / cerium organic complex and zinc soap in a mass ratio of 3:1. It is lead-free and cadmium-free. Rare earth ions promote PVC cross-linking and improve wear resistance.

[0039] Surface-functionalized carbon nanotubes assist in conductivity and provide wear resistance. Carboxylated multi-walled carbon nanotubes are used, and polyethylene glycol molecular chains are grafted onto their surface at a grafting rate of 8-12 wt%, which enhances conductivity. Grafting polyethylene glycol improves dispersibility and forms a "point-to-surface" synergistic conductivity with MXene.

[0040] KH-550 coupling agent is used for surface treatment, and aminopropyltriethoxysilane is used to improve the inorganic / organic interface bonding and enhance the filler-PVC interface strength.

[0041] The lubricant uses oxidized polyethylene wax and pentaerythritol stearate to reduce processing energy consumption and prevent thermal degradation.

[0042] This invention also provides a method for preparing environmentally friendly, wear-resistant, long-lasting antistatic PVC granules, comprising the following steps:

[0043] S1. Preparation of ionic liquid-modified MXene hybrids, using Ti3C2T X MXene material was dispersed in anhydrous ethanol to obtain a solid-liquid mixture with a solid content of 5%. The mixture was ultrasonically treated at 40 kHz for 30 min, and then Ti3C2T was added. X 20% by weight of [BMIM]PF6 ionic liquid was reacted at 70°C for 2 hours, and then centrifuged and dried to obtain ionic liquid modified MXene hybrid for later use.

[0044] S2. To prepare a nano-alumina / silicone composite wear-resistant agent, nano-α-Al2O3 particles were stirred at 800 rpm in a high-speed mixer under heating conditions of 80℃, and silicone resin was sprayed in. The amount of silicone resin added was 10% of the mass of nano-α-Al2O3 particles. The reaction was carried out for 15 min to obtain the nano-alumina / silicone composite wear-resistant agent for later use.

[0045] S3. Gradient mixing and granulation, using a co-rotating twin-screw extruder with a speed of 250-300 rpm. The temperature gradients for each zone are: feeding zone 130℃, melting zone 145℃, dispersion zone 155℃, homogenization zone 150℃, and die 145℃. PVC resin, a portion of bio-based plasticizer, coupling agent, nano-alumina / silicone composite wear-resistant agent, ionic liquid-modified MXene hybrid, surface-functionalized carbon nanotubes, the remaining bio-based plasticizer, rare earth composite heat stabilizer, and lubricant are added sequentially. After homogenization, the mixture is extruded through the die. Specifically, this includes:

[0046] S31. Add PVC resin and 1 / 3 of the total mass of bio-based plasticizer to a co-rotating twin-screw extruder and pre-plasticize at 130°C for 5 minutes;

[0047] S32. Add nano-alumina / silicone composite wear-resistant agent and coupling agent, and mix at 145℃ for 3 minutes;

[0048] S33. Add ionic liquid-modified MXene hybrid, surface-functionalized carbon nanotubes and the remaining bio-based plasticizer, and mix at 155°C for 8 minutes.

[0049] S34. Add rare earth composite heat stabilizer and lubricant, homogenize at 150℃, and then extrude at 145℃ through a die.

[0050] S4. Two-stage exhaust granulation: the first stage involves vacuum exhaust from the die head at a pressure of -0.08MPa; the second stage involves underwater pelletizing at a water temperature of 35-45℃, with a pellet size of 3mm×3mm. After pelletizing, the exhaust gas is treated with activated carbon adsorption and catalytic combustion devices, and then dried in a 60℃ fluidized bed until the moisture content is ≤0.1%, thus producing environmentally friendly, wear-resistant, long-lasting, and antistatic PVC pellets.

[0051] The present invention will now be described in detail with reference to specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art, and the raw materials used are all commercially available industrial-grade products with a purity ≥99%.

[0052] Example 1:

[0053] This embodiment provides an environmentally friendly, wear-resistant, long-lasting, antistatic PVC granule, which, by weight, consists of the following components: 60 parts of PVC resin (SG-5, average degree of polymerization 1000), 4 parts of ionic liquid modified MXene hybrid, 15 parts of nano-alumina / silicone composite wear-resistant agent, 10 parts of bio-based plasticizer, 3 parts of rare earth composite heat stabilizer, 1.5 parts of surface-functionalized carbon nanotubes, 1.2 parts of coupling agent (γ-glycidyl etheroxypropyltrimethoxysilane, KH-560), and 1.5 parts of lubricant (pentaerythritol stearate, PETS).

[0054] Preparation method:

[0055] S1. Ionic liquid modified MXene hybrid: Ti3C2T x Disperse in anhydrous ethanol (5% solids), sonicate at 40 kHz for 30 min, add 20 wt% [BMIM]PF6, react at 70 ℃ for 2 h, centrifuge, vacuum dry at 80 ℃ for 12 h, and set aside for later use.

[0056] S2. Nano-alumina / silicone composite wear-resistant agent: In a high-speed mixer at 80℃ (800rpm), preheat 50nm α-Al2O3 for 3min, uniformly spray silicone resin (10% of the mass of α-Al2O3), continue stirring for 15min, cool and pulverize, and set aside.

[0057] S3. Gradient mixing and granulation: using a co-rotating twin-screw extruder (length-to-diameter ratio 40:1). The rotation speed is 280 rpm, and the temperature gradient is as follows: feeding zone 130℃, melting zone 145℃, dispersing zone 155℃, homogenizing zone 150℃, and die head 145℃. Feed materials in the following order:

[0058] S31. PVC resin and 1 / 3 bio-based plasticizer, pre-plasticized for 5 minutes;

[0059] S32. Add nano-alumina / silicone composite wear-resistant agent and KH-560, and mix for 3 minutes;

[0060] S33. Add ionic liquid-modified MXene hybrid, carbon nanotubes and remaining plasticizer, and mix for 8 minutes;

[0061] S34. Add rare earth composite heat stabilizer and PETS, homogenize for 2 minutes, and then extrude through the die.

[0062] S4. Two-stage exhaust granulation: First-stage die vacuum degree -0.08MPa; second-stage underwater pelletizing (3mm×3mm, water temperature 40℃), 60℃ fluidized bed drying to moisture content ≤0.1%, exhaust gas is treated by activated carbon adsorption + catalytic combustion to obtain the final granules.

[0063] Example 2:

[0064] The difference between this embodiment and Example 1 is as follows: 65 parts PVC resin, 5 parts ionic liquid modified MXene hybrid, 18 parts nano-alumina / silicone composite wear-resistant agent, 12 parts bio-based plasticizer, 3.5 parts rare earth composite heat stabilizer, 2 parts surface-functionalized carbon nanotubes, 1.5 parts coupling agent, and 1.8 parts lubricant. The extruder process parameters remain unchanged, except that the dispersion zone temperature is increased to 158°C to accommodate higher filler content.

[0065] Example 3:

[0066] The difference between this embodiment and Example 1 is as follows: 55 parts PVC resin, 3 parts ionic liquid modified MXene hybrid, 12 parts nano-alumina / silicone composite wear-resistant agent, 8 parts bio-based plasticizer, 2.5 parts rare earth composite heat stabilizer, 1 part surface-functionalized carbon nanotubes, 0.8 parts coupling agent, and 1.2 parts lubricant. To reduce viscosity, the homogenization temperature was lowered to 148°C; otherwise, it was the same as in Example 1.

[0067] Example 4:

[0068] The difference between this embodiment and Example 1 is that: in the preparation process of the ionic liquid modified MXene hybrid, the ultrasonic time was extended to 45 min and the reaction temperature was increased to 75 °C to improve the interlayer intercalation rate of MXene; the interlayer spacing of the resulting hybrid increased from 1.2 nm to 1.6 nm, and the surface resistivity of the particles increased from 5 × 10⁻⁶. 6 Ω decreased to 3×10 6 Ω, volumetric wear rate reduced by 12%.

[0069] Example 5:

[0070] The difference between this embodiment and Embodiment 1 is that in the nano-alumina / silicone composite wear-resistant agent, the silicone resin coating amount is changed to 8wt%, the particle hardness (Shore D) is reduced from 78 to 75, but the wear amount (Taber H-18, 1000 cycles) is reduced from 0.015g to 0.012g, showing better scratch resistance.

[0071] Example 6:

[0072] The difference between this embodiment and Embodiment 1 is that the bio-based plasticizer is replaced by a mixture of epoxidized linseed oil and triethyl citrate in a 7:3 ratio, and the low-temperature embrittlement temperature of the granules is reduced from -25°C to -32°C, meeting the application requirements in cold regions.

[0073] Example 7:

[0074] The difference between this embodiment and Example 1 is that the ratio of La / Ce organic complex to zinc stearate in the rare earth composite heat stabilizer is changed to 2:1, the heat stabilization time at 180℃ is extended from 52 min to 58 min, and the initial colorability ΔE is reduced from 0.8 to 0.5.

[0075] Example 8:

[0076] The difference between this embodiment and Embodiment 1 is that the grafting rate of surface-functionalized carbon nanotubes is increased to 12 wt%, and the volume resistivity of the particles is increased from 1.2 × 10⁻⁶. 7 Ω·cm decreased to 8×10 6 The surface resistivity uniformity CV value decreased from 8% to 5% in Ω·cm.

[0077] Comparative Example 1:

[0078] Using commercially available ordinary antistatic PVC granules (containing fatty acid amide antistatic agents), under the same test conditions: surface resistivity 1×10⁻⁶ 11 The wear rate was 0.045 g, and the thermal stability time at 180°C was 28 min. Compared with Examples 1-8, the performance difference was significant.

[0079] Comparative Example 2:

[0080] Compared to Example 1, without the addition of ionic liquid-modified MXene hybrids, and using only carbon nanotubes as conductive fillers, the surface resistivity of the particles increased to 2 × 10⁻⁶. 8 The resistance was measured in Ω·cm, and the resistance increased by two orders of magnitude after being placed at 80℃ for 7 days, indicating that the MXene hybrid is crucial for long-term antistatic performance.

[0081] Performance testing

[0082] Volume resistivity was measured according to GB / T 1410-2006, wear loss was measured according to GB / T 3960-2016, and thermal stability time was measured according to GB / T2917.1-2002. The results of Examples 1-8 and comparative examples are shown in Table 1.

[0083] Table 1 Performance Test Results

[0084]

[0085]

[0086] As shown in Table 1, Examples 1-8 are superior to the comparative examples in terms of antistatic properties, wear resistance, thermal stability, and low-temperature toughness. Among them, Examples 4-8 achieved further improvement in comprehensive performance by optimizing process parameters and component ratios.

[0087] This invention has illustrated its principles and implementation methods using specific examples. The descriptions of these embodiments are merely illustrative of the method and its core ideas; furthermore, those skilled in the art will recognize that modifications may be made to the specific implementation methods and application scope based on the principles of this invention. Therefore, the content of this specification should not be construed as limiting the invention.

Claims

1. An environmentally friendly, wear-resistant, long-lasting, antistatic PVC granule, characterized in that: By mass fraction, it comprises: PVC resin 55-65 parts, ionic liquid modified MXene hybrid 3-5 parts, nano alumina / silicone composite wear-resistant agent 12-18 parts, bio-based plasticizer 8-12 parts, rare earth composite heat stabilizer 2.5-3.5 parts, surface functionalized carbon nanotube 1-2 parts, coupling agent 0.8-1.5 parts, lubricant 1.2-1.8 parts; The ionic liquid modified MXene hybrid is prepared by reacting Ti3C2TX type MXene material with [BMIM]PF6 ionic liquid at a mass ratio of 5:1; The nano alumina / silicone composite wear-resistant agent has a core-shell structure formed by coating silicone resin on nano α-Al2O3 particles, wherein the particle size of the nano α-Al2O3 particles is 50 nm, and the coating amount of the silicone resin is 10% of the mass of the nano α-Al2O3 particles; The surface functionalized carbon nanotube is a carboxylated multi-walled carbon nanotube, and a polyethylene glycol molecular chain is grafted on the surface thereof, and the grafting rate is 8-12wt%.

2. The environment-friendly long-wear anti-static PVC granules with wear resistance according to claim 1, characterized in that: The bio-based plasticizer is prepared by compounding epoxidized soybean oil and citric acid ester at a mass ratio of 6:

4. 3.The environment-friendly long-wearing and antistatic PVC granules according to claim 1, characterized in that: The rare earth composite heat stabilizer is prepared by mixing lanthanum / cerium organic complex and zinc soap at a mass ratio of 3:

1.

4. A method for preparing the environment-friendly long-wearing antistatic PVC granules according to any one of claims 1-3, characterized in that: The method comprises the following steps: S1. Preparation of ionic liquid modified MXene hybrid, disperse Ti3C2TX type MXene material in anhydrous ethanol to obtain a solid-liquid mixture, the solid content in the solid-liquid mixture is 5%, treat with 40 kHz ultrasonic for 30 min, add [BMIM]PF6 ionic liquid with a mass of 20% of the Ti3C2TX type MXene material, react at 70°C for 2 h, centrifugal dry to obtain ionic liquid modified MXene hybrid for standby; S2. Preparation of nano alumina / silicone composite wear-resistant agent, stir nano α-Al2O3 particles in a high-speed mixer at 80°C under heating condition at a speed of 800 rpm, spray silicone resin, the amount of silicone resin added is 10% of the mass of nano α-Al2O3 particles, react for 15 min to obtain nano alumina / silicone composite wear-resistant agent for standby; S3. Gradient mixing and granulation, use a co-rotating twin-screw extruder, add PVC resin, part of bio-based plasticizer, coupling agent, nano alumina / silicone composite wear-resistant agent, ionic liquid modified MXene hybrid, surface functionalized carbon nanotube, remaining bio-based plasticizer, rare earth composite heat stabilizer and lubricant in sequence, and then extrude through a die after homogenization; S4. Two-stage exhaust granulation, first-stage die vacuum exhaust, vacuum pressure is-0.08 MPa, second-stage underwater cutting, water temperature is 35-45°C, and then dry in a 60°C boiling bed until the moisture content is less than or equal to 0.1%, to obtain the environmentally friendly wear-resistant long-acting antistatic PVC granules.

5. The preparation method of the environment-friendly long-wearing and antistatic PVC granules according to claim 4, characterized in that: Step S3 specifically comprises: S31. Add PVC resin and bio-based plasticizer with a total mass of 1 / 3 to the co-rotating twin-screw extruder, and pre-plasticize at 130°C for 5 min; S32. Add nano alumina / silicone composite wear-resistant agent and coupling agent, and mix at 145°C for 3 min; S33. Add the ionic liquid modified MXene hybrid, surface functionalized carbon nanotubes and the remaining bio-based plasticizer, and mix at 155°C for 8 minutes; S34. Add the rare earth composite heat stabilizer and lubricant, homogenize at 150°C, and then extrude at 145°C.

6. The preparation method of the environment-friendly wear-resistant long-acting antistatic PVC granules according to claim 5, characterized in that: The rotational speed of the co-rotating twin-screw extruder was 250-300 rpm, and the temperature gradient of each zone was: 130°C for the feeding zone, 145°C for the melting zone, 155°C for the dispersion zone, 150°C for the homogenization zone, and 145°C for the die.

7. The preparation method of the environment-friendly wear-resistant long-acting antistatic PVC granules according to claim 4, characterized in that: In step S4, the particle size of underwater pelletizing was 3mm×3mm, and the tail gas was treated by activated carbon adsorption and catalytic combustion device after pelletizing.

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