摘要
聚酰亚胺纤维是典型人工合成材料,其分子链中苯环与酰亚胺环交替连接,由于旋转能低且分子链呈现相对刚性,从而赋予材料高强度、高模量、耐高温、耐辐射、耐化学性及优异阻燃性,使其在高温气体过滤与分离领域具有良好的应用潜力。本文综述了以聚酰亚胺纤维为基体的纸基材料、膜材料及泡沫材料的制备技术,探讨了聚酰亚胺纤维基气体过滤与分离材料的最新研究进展,并对聚酰亚胺基气体过滤与分离材料的未来进行了展望。
冶金、钢铁、水泥、电力等工业大量排放的细微粉尘颗粒污染物(PM),在大气中与有毒物质结合易形成毒性雾
空气过滤技术旨在从气流中去除颗粒物,理想的过滤器应能高效捕捉杂质粒子且不妨碍空气流通。工业生产中广泛使用的空气净化器(如旋风分离器、洗涤塔、沉淀池)可用于去除大颗粒,但对于粒径<10 μm的颗粒去除效果有限。当从气流中高效去除粒径1 μm或更小的颗粒时,纤维过滤器通常具有更大的优
聚酰亚胺(PI)纤维属于典型有机纤维滤料,其分子主链上含有五元酰亚胺环和高密度苯环,由于苯环间具有显著共轭效应,主分子链键能高、分子间作用强,PI纤维展现出优异的机械强度和化学稳定
纤维过滤机制与效率机理图如

图1 纤维过滤机制与效率机理
Fig. 1 Analytical diagram of fiber filtration mechanism and efficienc
1)截留:由于纤维过滤材料中纤维的不规则排列,气流中微细颗粒的流向难以保持直线,因而粒径0.1~1 μm的小颗粒主要通过截留机制被捕集,且截留的捕集量随着粒径的增大而增
2)惯性撞击:由于空气过滤材料中纤维的复杂排列,当气流转向时,细小微粒在惯性作用下偏离并撞击沉积在纤维上,对于粒径0.3~1 μm的较大颗粒,惯性撞击成为主要的捕集机
3)布朗扩散:粒径≤1 μm的颗粒常表现出明显的布朗运动,且粒径越小,颗粒的布朗运动越显著;而布朗运动导致气溶胶粒子偏离其流
4)静电吸附:若粒子和纤维中有1个带电或2个均带电,则二者之间产生的静电相互作用会改变粒子的运动轨
5)重力效应:对大多数颗粒,重力效应对其捕集的影响较小,当粒径<0.5 μm时,则可忽略不
作为纤维过滤器的核心元件,滤料的选择极大影响着过滤器的使用寿命及过滤效

图2 PI制备原理及应用
Fig. 2 Preparation principle and application of PI
1908年,Bogert
我国的PI研发历程可追溯至20世纪60年代,上海合成纤维研究所作为先驱,率先采用干法纺丝工艺实现了PI纤维的小批量生
非织造法生产过滤材料不仅高效,且产品具有容尘量大、强度高、孔隙分布均匀的特
湿法造纸成形工艺制备过程简单、自动化程度高,制备得到的纸基过滤材料具有独特的三维网络结构且孔隙分布均

图3 PI@PDA@MOF纸基过滤材料过滤机理及过滤性能分
Fig. 3 Filtration mechanism and analysis of filtration performance of PI@PDA@MOF paper-based filter material
注 PDA为对苯二胺。
静电纺丝技术不仅制造装置简单、工艺可控、成本低廉,且生产出的纳米级纤维具有直径小、比表面积大、孔隙率高、孔径可调控等特性,是制备高效低阻过滤材料的理想工

图4 静电纺丝法制备PI纤维垫流程图及其过滤机理、过滤性能表
Fig. 4 Flow chart of PI fiber pad fabricated by electrostatic spinning and characterization of filtration mechanism and filtration performanc
冷冻干燥是制备有序多孔材料的常用方

图5 冷冻干燥制备PI气凝胶流程图及其过滤机理、过滤性能表
Fig. 5 Flow chart of freeze-drying preparation of PI aerogel and characterization of filtration mechanism and filtration performanc
袋式除尘技术是一种高效空气净化手段,其核心在于通过真空泵的强力作用将高温含尘烟气引至由高性能纤维制成的滤袋表面,依据滤料的物理过滤和滤料表面粉尘层形成的过滤层共同实现对空气中特定尺寸颗粒物的有效捕捉与拦截,从而实现烟气的过滤与清洁处理(

图6 袋式除尘器内部结构及PI除尘
Fig. 6 Internal structure of bag filter and PI dust ba
除机械性能好、热稳定性和耐化学性强、低介电性能以及耐辐射性等优异特性外,PI纤维的三叶形截面形态使其拥有相较圆形或豆形截面纤维更大的比表面积,可以极大提高其捕集粉尘的能力,即使烟气中含有超细粉尘,PI纤维也可有效捕集粉尘,且捕集到的粉尘均可集中于滤料表面,不易渗透至滤料内部堵塞纤维孔隙,不仅能有效降低运行阻力,还能有效清除粉尘。以上特性使PI纤维相较其余耐高温过滤材料,竞争优势更加明
PI纸基过滤材料是以PI纤维为原料,通过现代湿法造纸技术制备成形后,再对其进行酰亚胺化处理得到的。但由于PI纤维表面光滑钝化,缺少化学活性基团,传统打浆处理不会使其分丝帚
此外,Xie

图7 PI纤维基复合纸的制备及其过滤性能分
Fig. 7 Preparation of PI fiber-based composite paper and analysis of filtration performanc
注 以上均为质量比。
传统PI滤料由于过滤效率低、过滤压力大,难以满足应用需求。因此,科研工作者们将研究重点转向了具有更高比表面积和孔隙率的纳米纤维膜材料,纳米纤维膜的孔隙结构更加均匀细密,能显著降低尘埃颗粒堵塞的风险。此外,纳米纤维膜还具有良好的自清洁能力,有助于保证其使用寿命和过滤效果。Yi
王亚

图8 PI纳米纤维薄膜过滤机制示意图及其过滤性能分
Fig. 8 Schematic diagram of filtration mechanism and analysis of filtration performance of PI nanofiber membran
气凝胶是一种三维多孔材料,由于其孔隙体积可达总体积的99%,使其具有大比表面积、高孔隙率、高温稳定性和低导热系数等特
Qian

图9 PI/PVDF复合气凝胶的制备流程图及其过滤性能分
Fig. 9 Preparation flow chart and filtration analysis of PI/PVDF composite aerogel
注 PIFF-25/35为含有质量分数25%/35%PVDF的PI/PVDF复合气凝胶。
Wang
聚酰亚胺(PI)纤维基复合材料由于其优异的稳定性,在耐高温气体过滤与分离领域具有广阔的应用前景,但在应用中仍存在一定问题,如单一形态结构的PI过滤器的过滤效率和压降之间难以平衡。因此,新型PI纤维基空气过滤与分离材料的开发仍在向前推进,可能的解决策略和发展方向如下。
1)纤维表面处理:采用物理或化学方法对PI纤维表面进行处理,如等离子体处理、表面接枝改性、涂层技术等,以增强纤维表面的活性和亲水性,从而改善纤维在浆料中的分散性和纤维间的结合力,降低纤维表面的惰性,促进纤维之间的相互作用,提高稳定性和均匀性。
2)复合纤维技术:将PI纤维与其他类型的纤维(如天然纤维、合成纤维或纳米纤维)进行复合,形成复合纤维体系。通过综合不同纤维的优势性能,如改善浆料的流动性、提高纸张的柔韧性和强度,同时保持PI纤维的高温稳定性和耐腐蚀性。复合纤维技术还可以通过调整纤维配比和排列方式,进一步优化材料的整体性能。
3)纳米材料增强:将纳米粒子(如碳纳米管、石墨烯、纳米氧化物等)引入PI纤维中或涂覆在纤维表面,形成纳米复合材料。纳米材料的小尺寸效应和表面效应等特性可显著增强纳米复合材料的强度、模量和热稳定性。同时,纳米材料还能增强PI纤维与基体之间的界面结合力,提高材料的整体稳定性和耐久性。
参 考 文 献
RUBIN R. Profile: Institute for Health Metrics and Evaluation, WA, USA[J]. The Lancet, DOI: 10.1016/S0140-6736(17)30263-5. [百度学术]
GAUDERMAN W J, AVOL E, GILLILAND F, et al. The effect of air pollution on lung development from 10 to 18 years of age[J]. New England Journal of Medicine, 2004, 351(11): 1057-1067. [百度学术]
MATTI M M. Chemical characterization of particulate emissions from diesel engines: A review[J]. Journal of Aerosol Science, 2007, 38(11): 1079-1118. [百度学术]
NEL A. Air Pollution-related Illness: Effects of Particles[J]. Science, 2005, 308(5723): 804-806. [百度学术]
SUN Y L, WANG Z F, FU P Q, et al. Aerosol composition, sources and processes during wintertime in Beijing, China[J]. Atmospheric Chemistry and Physics, 2013, 13(9): 4577-4592. [百度学术]
LI P, WANG C Y, ZHANG Y Y, et al. Air Filtration in the Free Molecular Flow Regime: A Review of High-efficiency Particulate Air Filters Based on Carbon Nanotubes[J]. Small, 2014, 10(22): 4543-4561. [百度学术]
陈昌江, 陆振乾, 杨加左. 耐高温除尘滤料的研究进展[J]. 纺织科技进展, 2019(1): 1-3. [百度学术]
CHEN C J, LU Z Q, YANG J Z. Research progress of high temperature resistant dust filter media[J]. Advances in Textile Science and Technology, 2019(1): 1-3. [百度学术]
贾峰峰, 闫 宁, 李娇阳, 等. 聚酰亚胺纤维及其纸基功能材料研究进展[J]. 中国造纸学报, 2022, 37(3): 126-134. [百度学术]
JIA F F, YAN N, LI J Y, et al. Research Progress in Polyimide Fiber and Its’ Paper-based Functional Materials[J]. Transactions of China Pulp and Paper, 2022, 37(3): 126-134. [百度学术]
毛伟如, 周为民, 张培杰, 等. 三叶形截面的聚酰亚胺纤维: CN202865402U[P]. 2013-04-10. [百度学术]
MAO W R, ZHOU W M, ZHANG P J, et al. Polyimide fibers with trefoil cross section: CN202865402U[P]. 2013-04-10. [百度学术]
卢俊典. 聚酰亚胺纤维发展分析[J]. 化学工业, 2020, 38(3): 34-36. [百度学术]
LU J D. Polyimide fibers development and analysis[J]. Chemical Industry, 2020, 38(3): 34-36. [百度学术]
JUNG S, KIM J. Advanced Design of Fiber-based Particulate Filters: Materials, Morphology, and Construction of Fibrous Assembly[J]. Polymers, DOI:10.3390/polym12081714. [百度学术]
BARHATE R S, RAMAKRISHNA S. Nanofibrous filtering media: Filtration problems and solutions from tiny materials[J]. Journal of Membrane Science, 2007, 296(1/2): 1-8. [百度学术]
ZHU M, HAN J, WANG F, et al. Electrospun Nanofibers Membranes for Effective Air Filtration[J]. Macromolecular Materials and Engineering, DOI:10.1002/mame.201600353. [百度学术]
YANG C F. Aerosol Filtration Application Using Fibrous Media—An Industrial Perspective[J]. Chinese Journal of Chemical Engineering, 2012, 20(1): 1-9. [百度学术]
RAMSKILL E A, ANDERSON W L. The inertial mechanism in the mechanical filtration of aerosols[J]. Journal of Colloid Science, 1951, 6(5): 416-428. [百度学术]
郭莎莎. 袋式除尘器滤料的选择和技术发展[J]. 非织造布, 2006(6): 26-29. [百度学术]
GUO S S. Filter Materials Choice and Technology Development for Bag-type Dust Extractor[J]. Nonwovens, 2006(6): 26-29. [百度学术]
BOGERT M T, RENSHAW R R. 4-Amino-0-Phthalic Acid and Some of Its Derivatives.1[J]. Journal of the American Chemical Society, 1908, 30(7): 1135-1144. [百度学术]
汪称意, 李 光, 江建明,等. 聚酰亚胺研究新进展[J]. 化学进展, 2009, 21(1): 174-181. [百度学术]
WANG C Y, LI G, JIANG J M, et al. New advances in polyimide research[J]. Advances in Chemistry, 2009, 21(1): 174-181. [百度学术]
张瑞文. 聚亚酰胺纤维的性能与应用[J]. 产业用纺织品, 1991,9(2): 38-40. [百度学术]
ZHANG R W. Properties and applications of polyimide fibers[J]. Technical Textiles, 1991,9(2): 38-40. [百度学术]
李生柱, 吴建华, 朱小华, 等. 高性能聚酰亚胺的进展[J]. 化工新型材料, 2002,30(6): 19-24. [百度学术]
LI S Z, WU J H, ZHU X H, et al. Advances in high-performance polyimides[J]. New Chemical Materials, 2002, 30(6): 19-24. [百度学术]
杨军杰, 逄媛媛, 卢 晶,等. 国产耐高温聚酰亚胺纤维的产业化[J]. 高科技纤维与应用, 2013, 38(1): 16-18. [百度学术]
YANG J J, PANG Y Y, LU J, et al. Industrialization of domestically produced high temperature resistant polyimide fibers[J]. High-tech Fiber and Application, 2013, 38(1): 16-18. [百度学术]
汪家铭. 聚酰亚胺纤维生产现状与市场前景(上)[J]. 上海化工, 2013, 38(2): 37-40. [百度学术]
WANG J M. Polyimide fiber production status quo and market outlook(Ⅰ)[J]. Shanghai Chemical Industry, 2013, 38(2): 37-40. [百度学术]
李 帅, 汪泽幸, 吴 璠,等. 聚酰亚胺耐高温过滤材料的研究现状[J]. 棉纺织技术, 2022, 50(S1): 43-47. [百度学术]
LI S, WANG Z X, WU F, et al. Research status of polyimide high temperature resistant filter materials[J]. Cotton Textile Technology, 2022, 50(S1): 43-47. [百度学术]
尚磊明, 李 蕾, 李艳香, 等. 复合聚酰亚胺滤毡的制备及其滤除PM2.5颗粒[J]. 过程工程学报, 2016, 16(5): 862-869. [百度学术]
SHANG L M, LI L, LI Y X, et al. Preparation of composite polyimide filter felt and its filtration of PM2.5 particles[J]. Journal of Process Engineering, 2016, 16(5): 862-869. [百度学术]
李 艳, 张得昆, 徐自超,等. 聚丙烯/聚酰亚胺纤维针刺非织造过滤材料的制备[J]. 合成纤维, 2020, 49(10): 29-33. [百度学术]
LI Y, ZHANG D K, XU Z C, et al. Preparation of nonwoven filtration materials from polypropylene/polyimide fibers[J]. Synthetic Fibers, 2020, 49(10): 29-33. [百度学术]
PANG W, SHI R, WANG J, et al. Research on Resin Used for Impregnating Polyimide Fiber Paper-based Composite Materials[J]. Materials, DOI:10.3390/ma14174909. [百度学术]
吴国光. 聚酰亚胺及其薄膜在现代纸业中的应用[J]. 中华纸业, 2010, 31(23): 81-84. [百度学术]
WU G G. Application of polyimide and its films in modern paper industry[J]. China Pulp & Paper Industry, 2010, 31(23): 81-84. [百度学术]
陆赵情, 徐 强, 丁孟贤,等. 芳纶浆粕影响聚酰亚胺纤维纸性能的研究[J]. 造纸科学与技术, 2013, 32(15): 23-27. [百度学术]
LU Z Q, XU Q, DING M X, et al. Study on the influence of aramid pulp meal on the properties of polyimide fiber paper[J]. Paper Science and Technology, 2013, 32(15): 23-27. [百度学术]
XIE F, ZHANG N, ZHUO L, et al. “MOF-cloth” formed via supramolecular assembly of NH2-MIL-101(Cr) crystals on dopamine modified polyimide fiber for high temperature fume paper-based filter[J]. Composites Part B: Engineering, 2019, 168:406-412. [百度学术]
王雅欣, 黄继伟, 凌新龙. 静电纺丝技术的发展现状及应用[J]. 纺织科学与工程学报, 2024, 41(2): 88-99. [百度学术]
WANG Y X, HUANG J W, LING X L. Current status and application of electrostatic spinning technology[J]. Journal of Textile Science and Engineering, 2024, 41(2): 88-99. [百度学术]
殷 平. 空气净化技术研究(1):纤维过滤[J]. 暖通空调, 2024, 54(5): 13-24. [百度学术]
YIN P. Research on air purification technology (1):Fiber filtration[J]. Journal of HVAC, 2024, 54(5): 13-24. [百度学术]
NAH C, HAN S H, LEE M H, et al. Characteristics of polyimide ultrafine fibers prepared through electrospinning[J]. Polymer International, 2003, 52(3): 429-432. [百度学术]
KARUBE Y, KAWAKAMI H. Fabrication of well-aligned electrospun nanofibrous membrane based on fluorinated polyimide[J]. Polymers for Advanced Technologies, 2010, 21(12): 861-866. [百度学术]
QIAO S, KANG S, ZHU J, et al. Facile strategy to prepare polyimide nanofiber assembled aerogel for effective airborne particles filtration[J]. Journal of Hazardous Materials, DOI: 10.1002/app.54705. [百度学术]
XIE F, WANG Y, ZHUO L, et al. Electrospun Wrinkled Porous Polyimide Nanofiber-based Filter via Thermally Induced Phase Separation for Efficient High-temperature PMs Capture[J]. ACS Applied Materials & Interfaces, DOI:10.1021/acsami.0c18143. [百度学术]
李猛猛. 聚酰亚胺气凝胶纤维的制备及其性能[D]. 上海: 东华大学, 2023. [百度学术]
LI M M. Preparation and properties of polyimide aerogel fibers[D]. Shanghai: Donghua University, 2023. [百度学术]
YUE W, CAO Y, HAN R, et al. A synergistic strategy for fabricating a highly flexible poly(m-phenylene isophthalamide) nanofiber-reinforced polyimide aerogel for high-temperature filtration[J]. Journal of Applied Polymer Science, DOI: 10.1002/app.54705. [百度学术]
张 楠. 聚酰亚胺纤维纸基高温烟气过滤材料的制备及性能研究[D]. 西安: 陕西科技大学, 2019. [百度学术]
ZHANG N. Preparation and performance study of polyimide fiber paper-based high temperature flue gas filtration material[D]. Xi’an: Shaanxi University of Science and Technology, 2019. [百度学术]
SCHINDLER N, 章 翔. P8
SCHINDLER N, ZHANG X. P8
朱晓光, 陈鄂生, 张美云. 聚酰亚胺纤维及其纸基功能材料研究进展[J]. 中国造纸, 2016, 35(10): 59-65. [百度学术]
ZHU X G, CHEN E S, ZHANG M Y. Research Progress on Polyimide Fibers and Their Paper-based Functional Materials[J]. China pulp & Paper, 2016, 35(10): 59-65. [百度学术]
魏 宁. 纳米SiO2改性聚酰亚胺纤维及其纸基材料性能研究[D]. 西安: 陕西科技大学, 2018. [百度学术]
WEI N. Research on the properties of nano-SiO2-modified polyimide fibers and their paper-based materials[D]. Xi’an: Shaanxi University of Science and Technology, 2018. [百度学术]
XIE F, ZHANG N, LU Z, et al. Highly improved mechanical and dielectric properties of paper-based composites with polyimide chopped fiber functionalized by ethylenediamine[J]. High Performance Polymers, 2019, 31(7): 852-860. [百度学术]
YI B, ZHAO Y, TIAN E, et al. High-performance polyimide nanofiber membranes prepared by electrospinning[J]. High Performance Polymers, 2019, 31(4): 438-448. [百度学术]
王亚芳. 静电纺丝法构筑聚酰亚胺基高温空气过滤材料及其性能研究[D]. 西安: 陕西科技大学, 2021. [百度学术]
WANG Y F. Construction of polyimide-based high-temperature air filtration materials by electrostatic spinning method and its performance [D]. Xi’an: Shaanxi University of Science and Technology, 2021. [百度学术]
PIERRE A C, PAJONK G M. Chemistry of Aerogels and Their Applications[J]. Chemical Reviews, 2002, 102(11): 4243-4266. [百度学术]
QIAN Z, WANG Z, CHEN Y, et al. Superelastic and ultralight polyimide aerogels as thermal insulators and particulate air filters[J]. Journal of Materials Chemistry A, 2018, 6(3): 828-832. [百度学术]
QIAO S, ZHANG H, KANG S, et al. Hydrophobic, Pore-tunable Polyimide/Polyvinylidene Fluoride Composite Aerogels for Effective Airborne Particle Filtration[J]. Macromolecular Materials and Engineering, DOI: 10.1002/mame.202000129. [百度学术]
WANG Q, BAI Y, XIE J, et al. Synthesis and filtration properties of polyimide nanofiber membrane/carbon woven fabric sandwiched hot gas filters for removal of PM2.5 particles[J]. Powder Technology, 2016, 29:254-263. [百度学术]
SHEN Y, XING J, SUN S, et al. Biomimetic strategy to prepare thermostable polyimide micro/nanofiber assembled aerogels for airborne particles filtration[J]. Journal of Environmental Chemical Engineering, DOI: 10.1016/j.jece.2022.108923. [百度学术]
WANG L, CUI L, LIU Y, et al. Electrospun polyimide nanofiber-coated polyimide nonwoven fabric for hot gas filtration[J]. Adsorption Science & Technology, 2018, 36(9/10): 1734-1743. [百度学术]