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木质素改性方法及其制备碳纤维的应用研究进展

沈聪浩 章沈翀 李靖 郭大亮 李静 沙力争

沈聪浩, 章沈翀, 李靖, 等. 木质素改性方法及其制备碳纤维的应用研究进展[J]. 复合材料学报, 2024, 41(4): 1764-1775. doi: 10.13801/j.cnki.fhclxb.20231007.003
引用本文: 沈聪浩, 章沈翀, 李靖, 等. 木质素改性方法及其制备碳纤维的应用研究进展[J]. 复合材料学报, 2024, 41(4): 1764-1775. doi: 10.13801/j.cnki.fhclxb.20231007.003
SHEN Conghao, ZHANG Shenchong, LI Jing, et al. Research progress of lignin modification method and its application in preparation of carbon fiber[J]. Acta Materiae Compositae Sinica, 2024, 41(4): 1764-1775. doi: 10.13801/j.cnki.fhclxb.20231007.003
Citation: SHEN Conghao, ZHANG Shenchong, LI Jing, et al. Research progress of lignin modification method and its application in preparation of carbon fiber[J]. Acta Materiae Compositae Sinica, 2024, 41(4): 1764-1775. doi: 10.13801/j.cnki.fhclxb.20231007.003

木质素改性方法及其制备碳纤维的应用研究进展

doi: 10.13801/j.cnki.fhclxb.20231007.003
基金项目: 浙江省“尖兵”“领雁”科技计划项目(2022C01066);浙江省自然科学基金项目(LTGS23C160001);浙江科技学院省属高校基本科研业务费(2023QN048;2023JLZD006)
详细信息
    通讯作者:

    李静,博士,副教授,硕士生导师,研究方向为植物纤维资源高效利用、木质素绿色分离与功能材料、纸基功能材料等E-mail: 116040@zust.edu.cn

  • 中图分类号: TQ342.742;TB332

Research progress of lignin modification method and its application in preparation of carbon fiber

Funds: The "Pioneer" and "Leading Goose" R&D Program of Zhejiang (2022C01066); Natural Science Foundation of Zhejiang Province (LTGS23C160001); Fundamental Research Funds for Zhejiang University of Science and Technology (2023QN048; 2023JLZD006)
  • 摘要: 木质素作为自然界最丰富的芳香族化合物,其含碳量达30%~40%,是制备碳纤维的优质原料。然而由于存在非晶态化学结构、低分子量、宽分子量分布和排列不良等特性,其复杂的非均质结构和固有的易絮凝特质需通过改性以克服。本文介绍了木质素的基本结构单元与特征,并在此基础上详细描述了物理混合、化学改性、生物作用等改性过程工艺条件及其对木质素结构及木质素基碳纤维的强度、电化学、过滤、透气等性能影响,并在此基础上对碳纤维在交通建筑、航空航天、生命健康及新能源等领域应用进行了拓展探讨。此外,拓展概述了木质素的定向官能团改性、绿色改性方法及改性过程表达等可行性,为木质素基碳纤维复合材料的进一步研究和开发提供思考,并推动其实现工业化应用。

     

  • 图  1  木质素的3种结构单元

    Figure  1.  Three structural units of lignin

    图  2  分级提取(SFE)法提取方案[12]

    Figure  2.  Stepwise fractionation extraction (SFE) extraction scheme[12]

    FAL—Fractionated alkali lignin; AL—Alkali lignin; Aq.—Aqueous solution

    图  3  木质素纯化流程图[13]

    Figure  3.  Flow chart of lignin purification[13]

    V1, V2—Valve 1, valve 2; P1—Pressure gage;T1, T2—Thermometer 1, thermometer 2

    图  4  含10wt%阔叶木硫酸盐木质素渗透液(HKLP)的碳化针叶木硫酸盐木质素渗透液(SKL)纤维的表面(a)和纤维截面(b)[15]

    Figure  4.  Fiber surface (a) and cross-section (b) of carbonized soft-wood kraft lignin (SKL) fiber containing 10wt% hardwood kraft lignin permeate (HKLP)[15]

    图  5  碘处理防止纤维坍塌机制[16]

    Figure  5.  Mechanism of iodine treatment to prevent fiber collapse[16]

    图  6  木质素与醋酸纤维素制备碳纤维流程图[17]

    Figure  6.  Flow chart of preparing carbon fiber from lignin and cellulose acetate[17]

    图  7  纳米纤维垫预氧化及不同温度下碳化的SEM图像:(a) 250℃预氧化;(b) 600℃碳化;(c) 800℃碳化;(d) 1000℃碳化;(e) 1200℃碳化;(f) 1400℃碳化[32]

    Figure  7.  SEM images of nanofiber mat preoxidation and carbonization at different temperatures: (a) 250℃ preoxidation; (b) 600℃ carbonization; (c) 800℃ carbonization; (d) 1000℃ carbonization; (e) 1200℃ carbonization; (f) 1400℃ carbonization[32]

    图  8  多孔碳纳米纤维的合成过程示意图:(a) 木质素/聚乙烯吡咯烷酮(PVP)基碳纳米多孔纤维;(b) 木质素/PVP/Mg(NO3)2基碳纳米多孔纤维[37]

    Figure  8.  Schematic diagram of the synthesis process of porous carbon nanofibers: (a) Lignin/polyvinylpyrrolidone (PVP)-based carbon nanofibers; (b) Lignin/PVP/Mg(NO3)2-based carbon nanofibers[37]

    图  9  负载银纳米粒子的聚乙烯醇(PVA)-木质素纳米纤维垫制备示意图[39]

    Figure  9.  Schematic diagram of preparing polyvinyl alcohol (PVA)-lignin nanofiber pads loaded with silver nanoparticles[39]

    图  10  二甲亚砜(DMSO)-水凝结剂纺成木质素/聚丙烯腈(L/P)前驱纤维的SEM图像:(a) L25/P75;(b) L35/P65;(c) L45/P55[26]

    Figure  10.  SEM images of lignin/polyacrylonitrile (L/P) precursor fibers spun in dimethyl sulfoxide (DMSO)-water coagulant: (a) L25/P75; (b) L35/P65; (c) L45/P55[26]

    图  11  纯聚丙烯腈(PAN)纤维和添加0.2wt%木质素的DMSO-水凝结剂纺成的L/P纤维的SEM图像:(a) PAN;(b) L25/P75;(c) L35/ P65;(d) L45/P55;(e) L50/P50[26]

    Figure  11.  SEM images of pure polyacrylonitrile (PAN) fiber and L/P fibers spun in DMSO-water coagulant with additional 0.2wt% lignin: (a) PAN; (b) L25/P75; (c) L35/P65; (d) L45/P55; (e) L50/P50[26]

    图  12  木质素丁酸化将羟基转化为酯的反应机制[45]

    Figure  12.  Mechanism of hydrolysis of hydroxyl group to ester by lignin butyrate[45]

    1-MI—1-methylimidazole

    图  13  软木硫酸盐木质素(SKL)与乳酸氯化物(LCl)的酯化反应[46]

    Figure  13.  Esterification reaction between softwood kraft lignin (SKL) and lactic acid chloride (LCl)[46]

    图  14  SKL与聚乳酸氯化物(PLCl)的酯化反应[46]

    Figure  14.  Esterification reaction between SKL and polylactic acid chloride (PLCl)[46]

    图  15  基于氮硫共掺杂石墨烯(GNs-N-S)共掺杂活性木质素基碳纳米纤维生产超级电容器的工艺示意图[52]

    Figure  15.  Process diagram of supercapacitor production based on GNs-N-S co-doped active lignin-based carbon nanofibers[52]

    VE:VW—Volume ratio of ethanol and water; DMF—N, N-dimethylformamide; PAN—Polyacrylonitrile; GNs—Graphene; HVPS—High voltage power supply; ACNFs—Nitorgen and sulphur co-doped graphene modified lignin/polyacrylonitrile-based carbon nanofiber

    表  1  木质素基碳纤维原料及其处理方式和碳纤维性能

    Table  1.   Lignin-based carbon fiber raw materials, treatment methods and properties of carbon fiber

    Material Aids Treatment Carbon fiber properties
    Calcium lignosulfonate[20] Acrylonitrile, itaconic acid Copolymerization Tensile strength: 1.74 GPa
    Tensile modulus: 210 GPa
    Pyrolytic lignin[21] Polyethylene terephthalate Copolymerization Average diameter: 12.6 μm
    Tensile strength: 1220 MPa
    Pyrolytic lignin[22] Acryloyl chloride Modified Tensile strength: 1.70 GPa
    Tensile modulus: 182 GPa
    Softwood kraft lignin[23] Acetic anhydride Modified Tensile strength: 1.04 GPa
    Tensile modulus: 52 GPa
    Softwood lignin[24] Stearic acid Modified Average diameter: 48.6 μm
    Tensile strength: 640 MPa
    Tensile modulus: 70.7 GPa
    Organosolv lignin from
    Alamo switchgrass[25]
    Organosolv lignin from yellow poplar Mix Average diameter: 15.7 μm
    Tensile strength: 747 MPa
    Tensile modulus: 41.8 GPa
    Softwood kraft lignin[26] Polyacrylonitrile Mix Tensile strength: 1.2 GPa
    Tensile modulus: 130 GPa
    Softwood kraft lignin[27] Polyvinyl alcohol Mix Average diameter: 12.6 μm
    Tensile strength: 351 MPa
    Tensile modulus: 44.5 GPa
    Kraft lignin[28] Cellulose Mix Tensile strength: 780 MPa
    Tensile modulus: 68 GPa
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  • [1] BAKER D A, RIALS T G. Recent advances in low-cost carbon fiber manufacture from lignin[J]. Journal of Applied Polymer Science, 2013, 130(2): 713-728. doi: 10.1002/app.39273
    [2] XU X. Application of carbon fiber cement-based composites in improving construction durability[J]. International Journal of Analytical Chemistry, 2022, 2022: 2323534.
    [3] WANG X, PAN L, ZHENG A, et al. Multifunctionalized carbon-fiber-reinforced polyetheretherketone implant for rapid osseointegration under infected environment[J]. Bioactive Materials, 2023, 24: 236-250. doi: 10.1016/j.bioactmat.2022.12.016
    [4] BACHMANN J, HIDALGO C, BRICOUT S. Environmental analysis of innovative sustainable composites with potential use in aviation sector—A life cycle assessment review[J]. Science China Technological Sciences, 2017, 60(9): 1301-1317. doi: 10.1007/s11431-016-9094-y
    [5] 李长庚, 靳汇奇, 杨晨峰, 等. 木质素绿色有机溶剂分级研究进展[J]. 中国造纸学报, 2023, 38(2): 19-27.

    LI Changgeng, JIN Huiqi, YANG Chenfeng, et al. Research progress on lignin fractionation by green organic solvent[J]. Transactions of China Pulp and Paper, 2023, 38(2): 19-27(in Chinese).
    [6] GRGAS D, RUKAVINA M, BEŠLO D, et al. The bacterial degradation of lignin—A review[J]. Water, 2023, 15(7): 1272. doi: 10.3390/w15071272
    [7] MOHAMAD AINI N A, OTHMAN N, HUSSIN M H, et al. Hydroxymethylation-modified lignin and its effectiveness as a filler in rubber composites[J]. Processes, 2019, 7(5): 315. doi: 10.3390/pr7050315
    [8] TOLBERT A, AKINOSHO H, KHUNSUPAT R, et al. Characterization and analysis of the molecular weight of lignin for biorefining studies[J]. Biofuels, Bioproducts and Biorefining, 2014, 8(6): 836-856. doi: 10.1002/bbb.1500
    [9] 姜波, 郭新宇, 焦欢, 等. 木质素基复合材料的直写式3D打印及其功能应用[J]. 复合材料学报, 2023, 40(4): 1913-1923.

    JIANG Bo, GUO Xinyu, JIAO Huan, et al. Direct ink writing of lignin-based composites and their applications[J]. Acta Materiae Compositae Sinica, 2023, 40(4): 1913-1923(in Chinese).
    [10] 李小玉, 李广慈, 李学兵. 不同化学法分离解聚过程对木质素结构的影响[J]. 辽宁石油化工大学学报, 2020, 40(1): 1-9. doi: 10.3969/j.issn.1672-6952.2020.01.001

    LI Xiaoyu, LI Guangci, LI Xuebing. Effect of chemical separation and depolymerization processes on lignin structure[J]. Journal of Liaoning Petrochemical University, 2020, 40(1): 1-9(in Chinese). doi: 10.3969/j.issn.1672-6952.2020.01.001
    [11] LI Y F, GE X Y, SUN Z P, et al. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw[J]. Bioresource Technology, 2015, 186: 316-320. doi: 10.1016/j.biortech.2015.03.058
    [12] SHI X J, DAI Z, CAO Q P, et al. Stepwise fractionation extracted lignin for high strength lignin-based carbon fibers[J]. New Journal of Chemistry, 2019, 43(47): 18868-18875. doi: 10.1039/C9NJ04942H
    [13] JIN J, DING J H, KLETT A, et al. Carbon fibers derived from fractionated-solvated lignin precursors for enhanced mechanical performance[J]. ACS Sustainable Chemistry & Engineering, 2018, 6(11): 14135-14142.
    [14] ZHU M N, LIU H, CAO Q P, et al. Electrospun lignin-based carbon nanofibers as supercapacitor electrodes[J]. ACS Sustainable Chemistry & Engineering, 2020, 8(34): 12831-12841.
    [15] NORDSTRÖM Y, NORBERG I, SJÖHOLM E, et al. A new softening agent for melt spinning of softwood kraft lignin[J]. Journal of Applied Polymer Science, 2013, 129(3): 1274-1279. doi: 10.1002/app.38795
    [16] DAI Z, SHI X J, LIU H, et al. High-strength lignin-based carbon fibers via a low-energy method[J]. RSC Advances, 2018, 8(3): 1218-1224. doi: 10.1039/C7RA10821D
    [17] SCHREIBER M, VIVEKANANDHAN S, MOHANTY A K, et al. Iodine treatment of lignin-cellulose acetate electrospun fibers: Enhancement of green fiber carbonization[J]. ACS Sustainable Chemistry & Engineering, 2015, 3(1): 33-41.
    [18] ATTIA A A M, ABAS K M, AHMED NADA A A, et al. Fabrication, modification, and characterization of lignin-based electrospun fibers derived from distinctive biomass sources[J]. Polymers, 2021, 13(14): 2277. doi: 10.3390/polym13142277
    [19] GHOSH T, NGO T D, KUMAR A, et al. Cleaning carbohydrate impurities from lignin using Pseudomonas fluorescens[J]. Green Chemistry, 2019, 21(7): 1648-1659. doi: 10.1039/C8GC03341B
    [20] LIU D P, OUYANG Q, JIANG X F, et al. Thermal properties and thermal stabilization of lignosulfonate-acrylonitrile-itaconic acid terpolymer for preparation of carbon fiber[J]. Polymer Degradation and Stability, 2018, 150: 57-66. doi: 10.1016/j.polymdegradstab.2018.02.013
    [21] QU W D, BAI X L. Thermal treatment of pyrolytic lignin and polyethylene terephthalate toward carbon fiber production[J]. Journal of Applied Polymer Science, 2020, 137(26): 48843. doi: 10.1002/app.48843
    [22] LUO Y X, QU W D, COCHRAN E, et al. Enabling high-quality carbon fiber through transforming lignin into an orientable and melt-spinnable polymer[J]. Journal of Cleaner Production, 2021, 307: 127252. doi: 10.1016/j.jclepro.2021.127252
    [23] ZHANG M, OGALE A A. Carbon fibers from dry-spinning of acetylated softwood kraft lignin[J]. Carbon, 2014, 69: 626-629. doi: 10.1016/j.carbon.2013.12.015
    [24] KANG D, LEE Y, PARK K H, et al. Carbon fibers derived from oleic acid-functionalized lignin via thermostabilization accelerated by UV irradiation[J]. ACS Sustainable Chemistry & Engineering, 2021, 9(14): 5204-5216.
    [25] HOSSEINAEI O, HARPER D P, BOZELL J J, et al. Improving processing and performance of pure lignin carbon fibers through hardwood and herbaceous lignin blends[J]. International Journal of Molecular Sciences, 2017, 18(7): 1410.
    [26] JIN J, OGALE A A. Carbon fibers derived from wet-spinning of equi-component lignin/polyacrylonitrile blends[J]. Journal of Applied Polymer Science, 2018, 135(8): 45903. doi: 10.1002/app.45903
    [27] FÖLLMER M, JESTIN S, NERI W, et al. Wet-spinning and carbonization of lignin-polyvinyl alcohol precursor fibers[J]. Advanced Sustainable Systems, 2019, 3(11): 1900082. doi: 10.1002/adsu.201900082
    [28] OLSSON C, SJÖHOLM E, REIMANN A. Carbon fibres from precursors produced by dry-jet wet-spinning of kraft lignin blended with kraft pulps[J]. Holzforschung, 2017, 71(4): 275-283.
    [29] WANG S C, ZHOU Z, XIANG H X, et al. Reinforcement of lignin-based carbon fibers with functionalized carbon nanotubes[J]. Composites Science and Technology, 2016, 128: 116-122. doi: 10.1016/j.compscitech.2016.03.018
    [30] LIU H C, CHIEN A T, NEWCOMB B A, et al. Processing, structure, and properties of lignin- and CNT-incorporated polyacrylonitrile-based carbon fibers[J]. ACS Sustainable Chemistry & Engineering, 2015, 3(9): 1943-1954.
    [31] ZHANG F, LIN J, ZHAO G. Preparation and characterization of modified soda lignin with polyethylene glycol[J]. Materials, 2016, 9(10): 822.
    [32] YOUE W J, LEE S M, LEE S S, et al. Characterization of carbon nanofiber mats produced from electrospun lignin-g-polyacrylonitrile copolymer[J]. International Journal of Biological Macromolecules, 2016, 82: 497-504. doi: 10.1016/j.ijbiomac.2015.10.022
    [33] QIN W, KADLA J F. Effect of organoclay reinforcement on lignin-based carbon fibers[J]. Industrial & Engineering Chemistry Research, 2011, 50(22): 12548-12555.
    [34] KIM M S, LEE D H, KIM C H, et al. Shell-core structured carbon fibers via melt spinning of petroleum- and wood-processing waste blends[J]. Carbon, 2015, 85: 194-200. doi: 10.1016/j.carbon.2014.12.100
    [35] BECK R J, ZHAO Y, FONG H, et al. Electrospun lignin carbon nanofiber membranes with large pores for highly efficient adsorptive water treatment applications[J]. Journal of Water Process Engineering, 2017, 16: 240-248. doi: 10.1016/j.jwpe.2017.02.002
    [36] CHO M, KARAASLAN M, CHOWDHURY S, et al. Skipping oxidative thermal stabilization for lignin-based carbon nanofibers[J]. ACS Sustainable Chemistry & Engineering, 2018, 6(5): 6434-6444.
    [37] MA C, LI Z Y, LI J J, et al. Lignin-based hierarchical porous carbon nanofiber films with superior performance in supercapacitors[J]. Applied Surface Science, 2018, 456: 568-576. doi: 10.1016/j.apsusc.2018.06.189
    [38] BENGTSSON A, BENGTSSON J, SEDIN M, et al. Carbon fibers from lignin-cellulose precursors: Effect of stabilization conditions[J]. ACS Sustainable Chemistry & Engineering, 2019, 7(9): 8440-8448.
    [39] ADIL K R, MUSSATTO S I, JHA H. Synthesis and characterization of silver nanoparticles loaded poly(vinyl alcohol)-lignin electrospun nanofibers and their antimicrobial activity[J]. International Journal of Biological Macromolecules, 2018, 120: 763-767. doi: 10.1016/j.ijbiomac.2018.08.109
    [40] CULEBRAS M, GEANEY H, BEAUCAMP A, et al. Bio-derived carbon nanofibres from lignin as high-performance Li-ion anode materials[J]. ChemSusChem, 2019, 12(19): 4516-4521. doi: 10.1002/cssc.201901562
    [41] SAUDI A, AMINI S, AMIRPOUR N, et al. Promoting neural cell proliferation and differentiation by incorporating lignin into electrospun poly(vinyl alcohol) and poly(glycerol sebacate) fibers[J]. Materials Science and Engineering: C, 2019, 104: 110005. doi: 10.1016/j.msec.2019.110005
    [42] PERERA JAYAWICKRAMAGE R A, BALKUS K J, FERRARIS J P. Binder free carbon nanofiber electrodes derived from polyacrylonitrile-lignin blends for high performance supercapacitors[J]. Nanotechnology, 2019, 30(35): 355402. doi: 10.1088/1361-6528/ab2274
    [43] THUNGA M, CHEN K K, GREWELL D, et al. Bio-renewable precursor fibers from lignin/polylactide blends for conversion to carbon fibers[J]. Carbon, 2014, 68: 159-166. doi: 10.1016/j.carbon.2013.10.075
    [44] CULEBRAS M, BEAUCAMP A, WANG Y, et al. Biobased structurally compatible polymer blends based on lignin and thermoplastic elastomer polyurethane as carbon fiber precursors[J]. ACS Sustainable Chemistry & Engineering, 2018, 6(7): 8816-8825.
    [45] DING R, WU H C, THUNGA M, et al. Processing and characterization of low-cost electrospun carbon fibers from organosolv lignin/polyacrylonitrile blends[J]. Carbon, 2016, 100: 126-136. doi: 10.1016/j.carbon.2015.12.078
    [46] GOULIS P, KARTSONAKIS I A, KONSTANTOPOULOS G, et al. Synthesis and processing of melt spun materials from esterified lignin with lactic acid[J]. Applied Sciences, 2019, 9(24): 5361.
    [47] MIKKILÄ J, TROGEN M, KOIVU K A Y, et al. Fungal treatment modifies kraft lignin for lignin- and cellulose-based carbon fiber precursors[J]. ACS Omega, 2020, 5(11): 6130-6140. doi: 10.1021/acsomega.0c00142
    [48] LIN J X, CHENG Y, LI Z, et al. Synthesis of modified lignin as an antiplasticizer for strengthening poly(vinyl alcohol)-lignin interactions toward quality gel-spun fibers[J]. ACS Applied Polymer Materials, 2022, 4(3): 1595-1607. doi: 10.1021/acsapm.1c01384
    [49] MUTHURAJ R, HORROCKS A R, KANDOLA B K. Hydroxypropyl-modified and organosolv lignin/bio-based polyamide blend filaments as carbon fibre precursors’[J]. Journal of Materials Science, 2020, 55(16): 7066-7083. doi: 10.1007/s10853-020-04486-w
    [50] STEUDLE L M, FRANK E, OTA A, et al. Carbon fibers prepared from melt spun peracylated softwood lignin: An integrated approach[J]. Macromolecular Materials and Engineering, 2017, 302(4): 1600441. doi: 10.1002/mame.201600441
    [51] CAO Q P, ZHU M N, CHEN J A, et al. Novel lignin-cellulose-based carbon nanofibers as high-performance supercapacitors[J]. ACS Applied Materials & Interfaces, 2020, 12(1): 1210-1221.
    [52] DAI Z, REN P G, JIN Y L, et al. Nitrogen-sulphur Co-doped graphenes modified electrospun lignin/polyacrylonitrile-based carbon nanofiber as high performance supercapacitor[J]. Journal of Power Sources, 2019, 437: 226937. doi: 10.1016/j.jpowsour.2019.226937
    [53] QU W D, XUE Y, GAO Y W, et al. Repolymerization of pyrolytic lignin for producing carbon fiber with improved properties[J]. Biomass and Bioenergy, 2016, 95: 19-26. doi: 10.1016/j.biombioe.2016.09.013
    [54] OUYANG Q, XIA K Q, LIU D P, et al. Fabrication of partially biobased carbon fibers from novel lignosulfonate-acrylonitrile copolymers[J]. Journal of Materials Science, 2017, 52(12): 7439-7451. doi: 10.1007/s10853-017-0977-x
    [55] MARADUR S P, KIM C H, KIM S Y, et al. Preparation of carbon fibers from a lignin copolymer with polyacrylonitrile[J]. Synthetic Metals, 2012, 162(5-6): 453-459.
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  • 收稿日期:  2023-08-01
  • 修回日期:  2023-09-11
  • 录用日期:  2023-09-16
  • 网络出版日期:  2023-10-08
  • 刊出日期:  2024-04-15

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