目的 本研究旨在对聚丙烯/聚乙烯（PP/PE）复合湿法无纺布基膜材料进行亲水改性,探究电子束预辐射法对膜布材料的改性工艺,在保持该材料力学性能的同时,提升其在碱性电池中的电解液浸润性与离子传导性,从而开发具有高吸液性与低电阻的碱性电池隔膜。方法 使用电子加速器对PP/PE复合膜布进行预辐射处理,随后在丙烯酸与α-烯基磺酸盐混合溶液中进行接枝反应。系统考察辐射强度、反应时间对接枝率及隔膜性能的影响,并通过吸液性能、力学强度、电化学阻抗与接触角等测试对不同程度改性后的膜布进行综合表征。结果 在辐射强度为100 kGy、单体质量分数为5%、反应温度为60 ℃、反应时间为6~8 h的优化条件下,接枝率达到44%~52%,膜布的综合性能得到大幅度提高。改性后的膜布吸液倍率由115%提升至最高420%,吸液速度由超过180 s缩短至24 s,湿电阻由1.85 Ω·cm2降至0.15 Ω·cm2,纵向最大拉断力保持在65 N以上。结论 电子束预辐射接枝法可显著提升PP/PE复合湿法无纺布的亲液性、离子传导性与尺寸稳定性,综合性能优异,具备良好的工业化应用潜力。
Abstract
This study aims to develop a high-performance and safe battery separator by modifying polypropylene/ polyethylene (PP/PE) composite wet-laid nonwoven fabric via electron beam pre-irradiation grafting technology, to enhance the separator's electrolyte wettability and ionic conductivity in alkaline batteries while rigorously maintaining its inherent mechanical properties—a critical parameter often compromised in conventional hydrophilic modifications.
Firstly, the PP/PE composite fabric was subjected to pre-irradiation with an electron accelerator to generate active sites. Subsequently, a grafting reaction was carried out in a mixed aqueous solution containing acrylic acid (AA) and α-olefin sulfonate (AOS) monomers. The synergistic action of these monomers was designed to impart durable hydrophilicity and potential sulfonic acid groups for improved ion transport. The effects of key processing parameters, including irradiation dose (kGy) and reaction time (h), on the grafting ratio and the resulting separator performance were systematically investigated. A comprehensive characterization of the modified membranes was performed, including evaluations of liquid absorption capacity and kinetics, mechanical strength (tensile testing), electrochemical performance (electrochemical impedance spectroscopy for area-specific resistance), and surface properties (contact angle measurements).
Under the optimized process conditions (irradiation dose: 100 kGy, monomer concentration: 5wt.%, reaction temperature: 60 ℃, reaction time: 6-8 h), a grafting ratio of 44% to 52% was achieved. This significant grafting level led to a remarkable enhancement in the separator's overall performance. The liquid absorption ratio increased dramatically from an initial 115% to a maximum of 420%, indicating a vastly improved porosity and affinity for the electrolyte. Concurrently, the electrolyte absorption time was drastically reduced from over 180 seconds to just 24 seconds, confirming superior wettability and capillary action. Most notably, the area-specific resistance (ASR) in the wet state, a direct indicator of ionic conductivity, decreased substantially from 1.85 Ω·cm2 to 0.15 Ω·cm2. This order-of-magnitude reduction was pivotal for minimizing internal resistance in battery applications. Importantly, these enhancements were achieved without sacrificing mechanical integrity. The longitudinal maximum tensile strength was maintained above 65 N, ensuring the separator's dimensional stability and mechanical robustness during cell assembly and operation.
The electron beam pre-irradiation grafting method has been successfully demonstrated as a highly effective technique for significantly improving the hydrophilicity (or more precisely, hydrophilicity towards electrolytes) and ionic conductivity of PP/PE composite wet-laid nonwoven fabric. The modified separator exhibits an excellent balance of properties: exceptional electrolyte uptake and wicking speed, dramatically reduced ionic resistance, and preserved mechanical/dimensional stability. This unique combination of performance metrics, achieved through a controllable radical grafting process, underscores the material's strong potential for industrial application as a next-generation separator in high-power alkaline batteries, where both safety and performance are paramount. Future work may focus on long-term stability tests in full cell configurations and further optimization of the monomer blend for targeted applications.
关键词
辐射接枝 /
电子加速器 /
亲水改性 /
电池隔膜 /
吸液性能
Key words
radiation grafting /
electron accelerator /
hydrophilic modification /
battery separator /
liquid absorption performance
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] LIU H, GU J, FAN H G, et al.Thermal Conversion Performance, Kinetic Mechanism, and Products of Electric Vehicle Lithium Battery Diaphragms[J]. Energy Conversion and Management, 2023, 295: 117612.
[2] SHAMCHI S, FARAHANI B V, BULLA M, et al.Mechanical Behavior of Lithium-Ion Battery Separators under Uniaxial and Biaxial Loading Conditions[J]. Polymers, 2024, 16(8): 1174.
[3] ZHANG D, DING L, WU T.Facile preparation of a lithium-ion battery separator with thermal shutdown function based on polypropylene/polyethylene microsphere composites[J]. Industrial & Engineering Chemistry Research, 2021(50):60.
[4] ANWAR A M, HAMID F H, SUMBOJA A, et al.Alginate-Based Electrospun Nanofiber for Sustainable High Ionic Conductivity Lithium-Ion Battery Separator[J]. ACS Applied Energy Materials, 2025, 8(8): 4954-4961.
[5] WARDANI A K, ARIONO D, SUBAGJO S, et al.Fouling Tendency of PDA/PVP Surface Modified PP Membrane[J]. Surfaces and Interfaces, 2020, 19: 100464.
[6] ZHOU Y Y, ZHANG J, WANG Z X, et al.A Modified TA-APTES Coating: Endowing Porous Membranes with Uniform, Durable Superhydrophilicity and Outstanding Anti-Crude Oil-Adhesion Property via One-Step Process[J]. Journal of Membrane Science, 2021, 618: 118703.
[7] 丁鸿志, 赵光, 赵帅生, 等. SiO2-TiO2-Al2O3多相复合超亲水涂层制备技术及其耐久性研究[J]. 表面技术, 2025, 54(14): 196-204.
DING H Z, ZHAO G, ZHAO S S, et al.Fabrication and Durability of SiO2-TiO2-Al2O3 Multi-Phase Superhydrophilic Coatings[J]. Surface Technology, 2025, 54(14): 196-204.
[8] MA Y L, YANG K, ZHANG Y, et al.Mechanical Properties and Thermal Stability of High-Temperature (Cooking Temperature)-Resistant PP/HDPE/POE Composites[J]. E-Polymers, 2024, 24: 20230164.
[9] USHA Z R, BABIKER D M D, YU R, et al. Super Hydrophilic Modified Biaxially Oriented Polypropylene Microporous Membrane for Excellent Gravity-Driven Oil/Water Emulsion Separation[J]. Journal of Membrane Science, 2022, 660: 120840.
[10] 余世勤, 赵鑫鹏, 郑艳, 等. 官能化聚烯烃的进展和应用[J]. 化工进展, 2022, 41(5): 2487-2503.
YU S Q, ZHAO X P, ZHENG Y, et al.Progess and Application of Functional Polyolefin[J]. Chemical Industry and Engineering Progress, 2022, 41(5): 2487-2503.
[11] 马留可, 马小路, 陈成, 等. 动力锂离子电池用聚烯烃隔膜改性研究进展[J]. 电源技术, 2018, 42(3): 452-454.
MA L K, MA X L, CHEN C, et al.Research Progress of Modification of Polyolefin Separators for Power Lithium Ion Battery[J]. Chinese Journal of Power Sources, 2018, 42(3): 452-454.
[12] HE Q L, LUO S L, JIN T Y, et al.Grafting-to and from for Multiplexed Chemical-Warfare-Agent Responsive Polymer Brushes[J]. Chemistry of Materials, 2023, 35(4): 1674-1683.
[13] 丁蕊蕊, 潘均安, 阳范文, 等. PET薄膜的亲水改性研究[J]. 表面技术, 2023, 52(4): 374-380.
DING R R, PAN J A, YANG F W, et al.Hydrophilic Modification of PET Film[J]. Surface Technology, 2023, 52(4): 374-380.
[14] PUROHIT P, BHATT A, MITTAL R K, et al.Polymer Grafting and Its Chemical Reactions[J]. Frontiers in Bioengineering and Biotechnology, 2023, 10: 1044927.
[15] BORISOV M, ERMAKOV A, KHANKIN V, et al.Racetrack Microtron—Pushing the Limits[J]. Symmetry, 2021, 13(12): 2244.
[16] ZHANG J, LIU Z Y, ZHANG X Y, et al.Hydrophilic Modification and Application of Polyvinylidene Fluoride- Based Blend Membrane[J]. ChemistrySelect, 2025, 10(36): e03441.
[17] ZHANG Z L, DING J Y, XIA Y, et al.Hydrophilic Modification of Polyethylene Membrane for Long Life Zinc-Bromide Flow Batteries[J]. Frontiers of Chemical Science and Engineering, 2025, 19(6): 48.
[18] LIU W Q, ZHAO N N, PAN Z C, et al.Functionalized Hydroxypropyl Methylcellulose Suspension Copolymerization Vinyl Chloride towards Preparation of Long- Term Stable Hydrophilic and Antifouling Ultrafiltration Membrane[J]. Separation and Purification Technology, 2025, 364: 132468.
[19] DONG X H, CHEN Z Y, SHENG K Y, et al.Electron Beam Irradiation-Induced Co-Grafting and Degradation of Cotton Cellulose with Ionic Liquid[J]. Radiation Physics and Chemistry, 2024, 214: 111291.
[20] SUN Y N, LIU X C, LIU T T, et al.Novel High- Efficiency Poly(butyl acrylate-co-2-ethylhexyl acrylate) Grafting of Poly(methyl methacrylate) Impact Modifier: Synthesis and Application[J]. Journal of Thermoplastic Composite Materials, 2023, 36(7): 2883-2897.
[21] ZHOU H F, LIU W H, ZHANG B W, et al.Regulation of Hydrophilic Performance for Chlorinated Polyethylene Grafting Acrylic Acid via Co-Irradiation[J]. Materials Letters, 2022, 311: 131576.
[22] DUNN C B, GUNTER Z, GRIFFIN A, et al.Tuning PolyolefinHydrophilicity to Control SulfonationCross- Linking Kinetics for Carbon Synthesis[J]. ACS Applied Engineering\nMaterials, 2025, 3(6): 1736-1744.
[23] 童赟, 王亚权, 田妮妮, 等. 超亲水木质素磺酸盐/超支化聚酰胺杂化接枝聚偏氟乙烯微滤膜的制备及分离性能研究[J]. 高分子通报, 2024, 37(8): 1073-1085.
TONG Y, WANG Y Q, TIAN N N, et al.Preparation and Separation Properties of Superhydrophilic Lignin Sulfonate/Hyperbranched Polyamide Hybrid Grafted Poly(Vinylidene Fluoride) Microfiltration Membranes[J]. Polymer Bulletin, 2024, 37(8): 1073-1085.
[24] ESQUIVEL-LOZANO Y A, LÓPEZ-SAUCEDO F, BUCIO E. Zinc Oxide Enhancing Hydrophilicity to [Polytetrafluoroethylene-Graft-Poly(Methyl Methacrylate)]- Graft-Poly(2-(diethylamino)Ethyl Methacrylate) Films[J]. Radiation Physics and Chemistry, 2022, 190: 109813.
[25] 张丙旭, 侯庆喜, 刘苇, 等. 采用湿法成形工艺制备聚烯烃碱性电池隔膜的研究[J]. 中国造纸, 2017, 36(9): 17-23.
ZHANG B X, HOU Q X, LIU W, et al.Preparation of Alkaline Battery Separator with Polyolefin Fibers by Using Wet-Laid Process[J]. China Pulp & Paper, 2017, 36(9): 17-23.
[26] 谢雅雯, 冯爽, 郜杰昌, 等. 两性离子添加剂调控界面微环境实现水系锌离子电池长循环[J]. 中国科学: 材料科学, 2024, 67(9): 2898-2907.
XIE Y W, FENG S, GAO J C, et al.Bipolar Ion Additives Regulate the Interface Microenvironment to Achieve Long-Term Cycling of Aqueous Zinc Ion Batteries[J]. Chinese Science: Materials Science, 2024, 67(9): 2898-2907.
基金
河南省电子束辐射工程技术研究中心运行经费（20251015002）; 河南省辐射化学新材料重点实验室运行经费（20251015001）
PDF(2024 KB)
渝公网安备 50010702501715号 渝ICP备15012534号-3
