Abs recycled plastic particles, preparation method and application thereof

Abstract

The present application belongs to the technical field of lead-acid storage battery, and particularly relates to ABS recycled plastic particles, a preparation method and application, which comprises the following components in percentage by weight: nano-silica 0.5-2.0%, SBS 5.0-8.0%, high-gum powder ASA 5.0-9.0%, acetylene black 1.5-2.5%, maleic anhydride grafted polypropylene wax 0.3-0.5%, carbon black 0.5-1.0%, and the rest is ABS. The present application completely solves the problem that the traditional ABS plastic shell is easy to fail in the low temperature, large temperature difference and strong corrosion environment in the north, so that the lead-acid storage battery can be scaled to develop the northern market, break the geographical use limit, and improve the overall life and capacity stability of the battery.

Description

Technical Field

[0001] This invention belongs to the technical field of lead-acid batteries, specifically relating to a method for preparing recycled ABS plastic particles and their application in the plastic casing of weather-resistant lead-acid batteries. Background Technology

[0002] Lead-acid batteries, widely used in automotive, telecommunications, and power industries, typically use acrylonitrile-butadiene-styrene copolymer (ABS resin) as their casing material. ABS resin possesses excellent mechanical properties, processing performance, and surface gloss, making it the mainstream material for lead-acid battery casings. However, with increasing environmental awareness and the promotion of resource recycling policies, more and more companies are beginning to try using recycled ABS plastic to replace virgin materials in order to reduce production costs and environmental pollution.

[0003] Because recycled ABS plastic has a complex origin and has undergone multiple processing and uses, its molecular chains have degraded to some extent, leading to a significant decrease in the material's mechanical properties, weather resistance, and processing stability. Especially in northern regions, lead-acid battery casings face severe challenges from extreme climatic conditions: on the one hand, there are large diurnal temperature differences, with surface temperatures exceeding 60°C in summer and autumn and dropping below -30°C in winter. The casings are prone to thermal deformation at high temperatures and cracking or even rupture at low temperatures due to insufficient toughness. On the other hand, long-term exposure to acid mist, ultraviolet radiation, and humid environments causes the material to age, discolor, and pulverize, severely impacting battery life and safety.

[0004] To improve the toughness, weather resistance, and corrosion resistance of ABS materials, existing technologies include modifications such as adding elastomers, inorganic fillers, and compatibilizers. For example, patent document CN105542379A discloses a high-impact, cold-resistant ABS box material and its preparation method and application. This material significantly improves the impact resistance and low-temperature toughness of ABS by adding maleic anhydride-grafted POE, high-resin ABS powder, and inorganic nanoparticles. This approach primarily targets virgin ABS and does not address issues such as impurities, degradation, and processing adaptability in recycled ABS systems. Another example is patent document CN121851538A, which discloses a long glass fiber reinforced polypropylene resin composite material and its preparation method. This material improves its resistance to damp heat and mechanical stability through interface modifiers and hydrophobic nano-silica. However, its matrix is ​​polypropylene, which differs significantly from the ABS system, making the technology difficult to directly transfer to recycled ABS.

[0005] Furthermore, existing technologies for the reuse of recycled ABS mostly focus on simple blending or adding a single additive, lacking a systematic design for the synergistic effects of multiple components. For example, some technical solutions (such as the nanocomposite high-viscosity, high-stability modified asphalt and its preparation method disclosed in patent document CN121406153A) improve toughness by adding SBS or ASA, but neglect the synergistic optimization of filler dispersibility, interfacial bonding strength, and long-term weather resistance. Meanwhile, recycled ABS often contains trace amounts of inorganic impurities, which, if not effectively modified, can easily lead to stress concentration points in the molded shell during injection molding, reducing yield and reliability.

[0006] In summary, existing research on the modification of recycled ABS plastic for lead-acid battery casings still has significant shortcomings: On the one hand, existing modification schemes are mostly geared towards virgin ABS, failing to effectively address the problems of deteriorated mechanical properties, poor processing stability, and insufficient weather resistance caused by molecular chain degradation and impurity introduction in recycled ABS; on the other hand, simple blending or the addition of single additives lacks a systematic design for the synergistic effects of multiple components, making it difficult to simultaneously consider the material's comprehensive properties such as low-temperature toughness, high-temperature deformation resistance, acid mist corrosion resistance, and UV aging resistance. Especially under extreme climatic conditions in northern regions, existing recycled ABS materials cannot meet the stringent requirements for long-term safety and reliability of lead-acid battery casings. Therefore, a new technical solution is needed to address the aforementioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing recycled ABS plastic particles and their application, in order to solve the problems mentioned in the background art, such as the inherent performance defects of recycled ABS plastic and the limitations of existing modification technologies, which restrict its large-scale and high-quality application.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a type of recycled ABS plastic particles, comprising the following components by weight percentage: 0.5-2.0% nano-silica, 5.0-8.0% SBS, 5.0-9.0% high-rubber powder ASA, 1.5-2.5% acetylene black, 0.3-0.5% maleic anhydride-grafted polypropylene wax, 0.5-1.0% carbon black, with the balance being ABS. The nano-silica conforms to GB / T 20020-2017; the acetylene black conforms to GB / T 3782-2017; the maleic anhydride-grafted polypropylene wax conforms to SH / T 1827-2019; the SBS is a styrene-butadiene-styrene block copolymer conforming to GB / T 8655-2019; the high-rubber powder ASA is a core-shell structured acrylonitrile-styrene-acrylate copolymer with a rubber weight content of 60-80%, conforming to GB / T 37194-2018; the carbon black conforms to GB / T 3780-2019; the ABS is made from recycled ABS plastic.

[0009] The specific steps for preparing ABS recycled plastic particles based on the above components and formulation are as follows: S1. Add the acetylene black and maleic anhydride-grafted polypropylene wax in the formula to a horizontal ribbon mixer and stir at a speed of 15-25 Hz for 10-18 minutes to obtain a blend of acetylene black and maleic anhydride-grafted polypropylene wax. The discharge port of the horizontal ribbon mixer also needs to be equipped with a 100-mesh screen vibration device. S2. First, add the blend obtained in S1 and the formulated amount of ABS and nano silica into the batching machine and mix for 3-7 minutes. Then, add the formulated amount of SBS, high-rubber powder ASA and carbon black into the batching machine and continue to stir and mix at a speed of 15-25 Hz for 10-15 minutes. S3. The material mixed in S2 is melted, extruded, and pelletized to obtain 2-5mm ABS recycled plastic particles. The melting process is divided into three stages: the temperature of the shearing section is 190-200℃, the temperature of the melting section is 195-220℃, and the temperature of the screen changing die section is 200-235℃, with a melt pressure of 8-15MPa. During extrusion, the main machine temperature is 190-220℃, the screw speed is 70-90r / min, the extrusion speed is 75-85r / min, and the cooling water temperature is 35-60℃.

[0010] In addition to the above technical solutions, the ABS recycled plastic particles prepared above can also be used in the plastic casing of weather-resistant lead-acid batteries.

[0011] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention, through a specific ratio and combination of nano-silica, SBS, high-rubber powder ASA, acetylene black, maleic anhydride-grafted polypropylene wax, and carbon black, forms a multi-component synergistic modification system. This system effectively overcomes the inherent defects of recycled ABS plastic, such as deteriorated mechanical properties, poor processing stability, and insufficient weather resistance caused by molecular chain degradation and impurity introduction. It achieves unexpected and significant improvements in several key properties, including low-temperature toughness, corrosion resistance, heat resistance, and processing stability. The performance of recycled materials surpasses that of virgin materials, breaking through the industry's technical prejudice that "recycled materials can only be used at low quality." This completely solves the problem of traditional ABS plastic shells being prone to failure in the low-temperature, large-temperature-difference, and highly corrosive environments of northern regions. This enables lead-acid batteries to be scaled up and expand into the northern market, breaking geographical limitations and improving the overall lifespan and capacity stability of the batteries.

[0012] 2. This invention uses 100% recycled ABS as the base material. After adding necessary modifiers, the overall cost is still 8-15% lower than that of commercially available non-recycled ABS products. It achieves a balance between high performance and low cost, as well as green environmental protection, which is in line with the development direction of green manufacturing and circular economy.

[0013] 3. This invention, by adding nano-silica to the formulation components, effectively improves the tensile strength and wear resistance of plastic particles, helps disperse internal stress generated during injection molding, prevents stress concentration, and also effectively improves the wear resistance and heat insulation performance of the plastic shell, helping to isolate the effects of extreme external temperatures on the battery interior, making the battery capacity more stable. By effectively dispersing the butadiene rubber phase in the ABS matrix using SBS, the toughness of the particle material at extreme low temperatures of -30 to -40℃ can be significantly improved, effectively preventing uneven stress and cracking of the plastic shell caused by large diurnal temperature differences in northern regions. It also improves the interfacial bonding force between nano-silica, acetylene black, and the matrix, avoiding stress concentration caused by filler agglomeration. Utilizing the high rubber content of high-rubber powder ASA, it effectively compensates for the decrease in toughness caused by impurities and colorants in recycled ABS plastic, and works synergistically with SBS to further enhance impact resistance. This process effectively improves the acid and corrosion resistance of ABS and slows down the color change of the plastic shell. Acetylene black and carbon black work together to provide coloring, and acetylene black is superior to traditional carbon black in maintaining toughness and further improves weather resistance, thereby enhancing the adaptability of the finished plastic shell in the extreme environment of large diurnal temperature differences in the north. Maleic anhydride-grafted polypropylene wax is used as a dispersant to effectively promote the distribution of acetylene black and enhance the interfacial compatibility between ABS, SBS, and ASA. The above components work synergistically within the weight percentage range, making the resulting recycled ABS plastic particles significantly superior to unmodified recycled ABS materials in key indicators such as low-temperature impact resistance, heat resistance dimensional stability, and dilute sulfuric acid corrosion resistance. This successfully solves the problem that recycled ABS cannot meet the stringent performance requirements of lead-acid battery plastic shells. In particular, its optimization for extreme climatic conditions in the north provides strong technical support for lead-acid battery products to expand into the northern market.

[0014] 4. This invention employs a stepwise mixing process (first premixing acetylene black and maleic anhydride-grafted polypropylene wax, then blending with ABS and nano-silica, and finally adding SBS, ASA, and carbon black), combined with a 100-mesh vibrating screen at the outlet of a horizontal ribbon mixer, effectively preventing large particle impurities from affecting subsequent processing. Simultaneously, the temperature and melt pressure are controlled in stages during melt extrusion to prevent further degradation of recycled ABS due to repeated thermal history, ensuring particle uniformity and processing stability.

[0015] 5. This invention addresses the extreme climatic conditions in northern regions, where there are large diurnal temperature differences, surface temperatures exceeding 60°C in summer and autumn, and temperatures dropping below -30°C in winter. It optimizes the low-temperature toughness, high-temperature deformation resistance, and weather resistance of recycled ABS plastic, effectively preventing problems such as thermal deformation of the plastic shell, low-temperature brittleness, and acid mist aging. It significantly extends the service life of lead-acid batteries in harsh environments and fills the gap in existing technologies where recycled ABS materials cannot meet the needs of the northern market. Detailed Implementation

[0016] The following examples are used to further illustrate the content of the present invention and do not limit the application of the present invention (all percentages below are weight percentages). Example 1:

[0017] First, weigh out 1.14% nano-silica, 5.07% SBS, 8.85% high-rubber powder ASA, 2.04% acetylene black, 0.40% maleic anhydride-grafted polypropylene wax, 0.50% carbon black, and 82.50% ABS (acrylonitrile-butadiene-styrene copolymer). The ABS is made from recycled ABS plastic. The nano-silica conforms to GB / T 20020-2017; the acetylene black conforms to GB / T 3782-2017; the maleic anhydride-grafted polypropylene wax conforms to SH / T 1827-2019; the SBS is a styrene-butadiene-styrene block copolymer conforming to GB / T 8655-2019; the high-rubber powder ASA is a core-shell structure acrylonitrile-styrene-acrylate copolymer with a rubber weight content of 60-80%, conforming to GB / T 37194-2018; and the carbon black conforms to GB / T 3780-2019.

[0018] ABS recycled plastic particles are then prepared based on the selected ABS recycled plastic particle components. The specific method for preparing ABS recycled plastic particles is as follows: First, 2.04% acetylene black and 0.40% maleic anhydride-grafted polypropylene wax are added to a horizontal ribbon mixer and stirred at a speed of 15-25 Hz for 10-18 minutes. A 100-mesh screen vibration device is installed at the discharge port to vibrate and discharge the powder to avoid large particles affecting subsequent production, thereby obtaining a blend of acetylene black and maleic anhydride-grafted polypropylene wax. Then, the blend obtained above is added to the batching machine along with 82.50% ABS and 1.14% nano silica and mixed for 3-7 minutes. Then, 5.07% SBS, 8.85% high-rubber powder ASA and 0.50% carbon black are added to the batching machine and stirred and mixed at a speed of 15-25 Hz for 10-15 minutes. Finally, the mixed material is fed into a melt at a pressure of 8-15 MPa, and then enters the shearing section at 190-200°C, the melting section at 195-220°C, and the screen changing die section at 200-235°C for melting treatment. After melting treatment, it is fed into an extruder with a main machine temperature of 190-220°C, a screw speed of 70-90 r / min, and an extrusion speed of 75-85 r / min, and is extruded under the action of cooling water at 35-60°C. The extruded material is then pelletized to obtain 2-5 mm ABS recycled plastic particles.

[0019] The ABS recycled plastic particles obtained above are then used as a plastic shell material in weather-resistant lead-acid batteries. Example 2:

[0020] The preparation process for ABS recycled plastic particles in this embodiment is the same as that in Example 1, only the formulation amounts are different, namely: 0.52% nano silica, 7.90% SBS, 6.77% high-rubber powder ASA, 1.51% acetylene black, 0.30% maleic anhydride grafted polypropylene wax, 0.70% carbon black, and 83.00% ABS.

[0021] Similarly, the preparation method and application of ABS recycled plastic particles in this embodiment are the same as in Example 1. Example 3:

[0022] The preparation process for ABS recycled plastic particles in this embodiment is the same as in Example 1, only the formulation amounts are different, namely: 1.96% nano silica, 6.88% SBS, 5.10% high-rubber powder ASA, 2.49% acetylene black, 0.50% maleic anhydride grafted polypropylene wax, 0.95% carbon black, and 83.07% ABS.

[0023] Similarly, the preparation method and application of ABS recycled plastic particles in this embodiment are the same as in Example 1.

[0024] The recycled ABS plastic particles from Examples 1-3 above were used to prepare 20Ah battery bottom cases. Meanwhile, ABS plastic shells without formula modification were used as comparative samples. Ten samples from each of the four formulas were taken and tested according to requirements exceeding GB / T 23754-2019 standards for corrosion resistance, low-temperature impact resistance, and heat resistance. Corrosion resistance: Under conditions of (60±3)℃, the sample was completely immersed in (1.280±0.001) g / mL dilute sulfuric acid for 192 h, and the mass change rate was ≤1.0%; Low temperature impact resistance: The plastic shell sample was left to stand for 3.5 hours in an environment of (-35~-40)℃. After the plastic shell was removed, a (500±5)g iron ball was dropped freely from a height of (300±2)mm above the upper surface of the plastic shell within 1 minute. The plastic shell was undamaged and had no cracks. Heat resistance: Pour hot water at (75±2)℃ into the plastic shell single-cell tank, with the liquid level at (20±2)mm from the tank opening, and then place it in a constant temperature chamber at (75±2)℃ for 4 hours. After cooling to room temperature, keep it for 24 hours. The dimensional change is ≤1.3mm.

[0025] The specific data is shown in the table below: ; As shown in the table above, the improved plastic shell of this invention exhibits significantly enhanced corrosion resistance and weather resistance. Therefore, this invention, through its unique formula and preparation process involving the synergistic modification of recycled ABS with multiple components, effectively overcomes the inherent defects of recycled ABS plastic, such as deteriorated mechanical properties, poor processing stability, and insufficient weather resistance caused by molecular chain degradation and impurity introduction. It achieves unexpected and significant improvements in several key properties, including low-temperature toughness, corrosion resistance, heat resistance, and processing stability, enabling recycled materials to outperform virgin materials. This breaks through the industry's technical prejudice that "recycled materials can only be used at low quality," thus completely solving the problem of traditional ABS plastic shells easily failing in the low-temperature, large-temperature-difference, and highly corrosive environments of northern regions. This allows lead-acid batteries to be scaled up and expanded into the northern market, breaking geographical limitations and improving the overall battery life and capacity stability.

Claims

1. A type of recycled ABS plastic particles, characterized in that, It comprises the following components by weight percentage: nano silica 0.5–2.0%, SBS 5.0–8.0%, high-resin powder ASA 5.0–9.0%, acetylene black 1.5–2.5%, maleic anhydride grafted polypropylene wax 0.3–0.5%, carbon black 0.5–1.0%, and the balance being ABS, wherein the ABS is made from recycled ABS plastic.

2. The ABS recycled plastic particles according to claim 1, characterized in that, The acetylene black conforms to GB / T3782-2017; the maleic anhydride-grafted polypropylene wax conforms to SH / T 1827-2019.

3. The ABS recycled plastic particles according to claim 1, characterized in that, The nano-silica conforms to GB / T 20020-2017.

4. The ABS recycled plastic particles according to claim 1, characterized in that, The SBS is a styrene-butadiene-styrene block copolymer, conforming to GB / T 8655-2019; the high-rubber powder ASA is a core-shell structured acrylonitrile-styrene-acrylate copolymer with a rubber weight content of 60-80%, conforming to GB / T 37194-2018; the carbon black conforms to GB / T3780-2019.

5. A method for preparing ABS recycled plastic particles according to any one of claims 1-4, characterized in that, The specific steps include the following: S1. The acetylene black and maleic anhydride-grafted polypropylene wax of the formula amount are put into a horizontal ribbon mixer and premixed to obtain a blend of acetylene black and maleic anhydride-grafted polypropylene wax. S2. First, add the blend obtained in S1 and the formula amount of ABS and nano silica into the batching machine and mix for 3-7 minutes. Then, add the formula amount of SBS, high-rubber powder ASA and carbon black into the batching machine for further stirring and mixing. S3. The material mixed in S2 is melted, extruded, and pelletized to obtain 2-5mm ABS recycled plastic particles.

6. The method for preparing recycled ABS plastic particles according to claim 5, characterized in that, In S1, the stirring speed is 15-25Hz and the stirring time is 10-18min. The discharge port of the horizontal ribbon mixer also needs to be equipped with a 100-mesh screen vibration device.

7. The method for preparing recycled ABS plastic particles according to claim 5, characterized in that, In S2, the stirring speed is 15-25 Hz and the stirring time is 10-15 min.

8. The method for preparing recycled ABS plastic particles according to claim 5, characterized in that, In S3, melting is divided into three stages: the temperature of the shearing section is 190-200℃, the temperature of the melting section is 195-220℃, the temperature of the screen changing mold section is 200-235℃, and the melt pressure is 8-15MPa.

9. The method for preparing recycled ABS plastic particles according to claim 5, characterized in that, In S3, the main extrusion temperature is 190–220℃, the screw speed is 70–90 r / min, the extrusion speed is 75–85 r / min, and the cooling water temperature is 35–60℃.

10. The application of ABS recycled plastic particles as described in any one of claims 1-4 in the plastic casing of a weather-resistant lead-acid battery.