{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:39:27Z","timestamp":1792805967424,"version":"4.5.0"},"reference-count":39,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2022,9,2]],"date-time":"2022-09-02T00:00:00Z","timestamp":1662076800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University","award":["ZKT39"],"award-info":[{"award-number":["ZKT39"]}],"id":[{"id":"https:\/\/ror.org\/010m3gk75","id-type":"ROR","asserted-by":"crossref"}]},{"name":"State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University","award":["51503111"],"award-info":[{"award-number":["51503111"]}],"id":[{"id":"https:\/\/ror.org\/010m3gk75","id-type":"ROR","asserted-by":"crossref"}]},{"name":"NSFC","award":["ZKT39"],"award-info":[{"award-number":["ZKT39"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]},{"name":"NSFC","award":["51503111"],"award-info":[{"award-number":["51503111"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>An optimized \u201crigid-flexible\u201d structure with multistage gradient modulus was constructed on carbon fiber (CF) surface via chemical grafting using \u201cflexible\u201d polyethyleneimine (PEI) and \u201crigid\u201d polydopamine (PDA) between \u201crigid\u201d CF and \u201cflexible\u201d epoxy (EP) to elaborate a double alternant \u201crigid-flexible\u201d structure for simultaneously strengthening and toughening CF\/EP composites. PDA and PEI polymers can greatly enhance the roughness and wettability of CF surfaces, further strengthening the mechanical interlocking and chemical interactions between CFs and epoxy. Besides, the \u201crigid-flexible\u201d structure endows the interface with a gradient transition modulus, which could uniformly transfer internal stress and effectively avoid the stress concentration. Moreover, the double alternant \u201crigid-flexible\u201d could buffer the external loading, induce more micro cracks and propagation paths and, thereby, consume more energy during the destruction of the composite. The interfacial shear strength, interlaminar shear strength, impact strength increased by 80.2%, 23.5% and 167.2%, and the fracture toughness improved by 227.2%, compared with those of the unmodified CF composite, respectively. This creative strategy and design afford a promising guidance for the preparation and production of advanced CF\/EP structural materials with high strength and toughness.<\/jats:p>","DOI":"10.3390\/nano12173056","type":"journal-article","created":{"date-parts":[[2022,9,7]],"date-time":"2022-09-07T01:51:57Z","timestamp":1662515517000},"page":"3056","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Constructing a Double Alternant \u201cRigid-Flexible\u201d Structure for Simultaneously Strengthening and Toughening the Interface of Carbon Fiber\/Epoxy Composites"],"prefix":"10.3390","volume":"12","author":[{"given":"Susu","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Han","sequence":"additional","affiliation":[{"name":"College of Physics, Qingdao University, Qingdao 266071, China"},{"name":"Weihai Innovation Institute, Qingdao University, Weihai 264200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lina","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaokai","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianfa","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zheng","family":"Gu","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"},{"name":"Weihai Innovation Institute, Qingdao University, Weihai 264200, China"},{"name":"Weifang Key Laboratory of Environmentally Friendly Macromolecular Flame Retardant Materials, Weifang 262715, China"},{"name":"Shandong Engineering Laboratory of Environmentally Friendly Macromolecular Flame Retardant Materials, Weifang 262715, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108065","DOI":"10.1016\/j.compscitech.2020.108065","article-title":"Mode-II fracture behaviour of aerospace-grade carbon fibre\/epoxy composites interleaved with thermoplastic veils","volume":"191","author":"Quan","year":"2020","journal-title":"Compos. Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5262","DOI":"10.1002\/anie.201306129","article-title":"Carbon Fibers: Precursor Systems, Processing, Structure, and Properties","volume":"53","author":"Frank","year":"2014","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2225","DOI":"10.1002\/app.39282","article-title":"Recent progress in interfacial toughening and damage self-healing of polymer composites based on electrospun and solution-blown nanofibers: An overview","volume":"130","author":"Wu","year":"2013","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.msea.2018.08.025","article-title":"Reinforcing effects of carbon nanotube on carbon\/carbon composites before and after heat treatment","volume":"735","author":"Han","year":"2018","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"152717","DOI":"10.1016\/j.apsusc.2022.152717","article-title":"Interfacial reinforcement of composites by the electrostatic self-assembly of graphene oxide and NH3 plasma-treated carbon fiber","volume":"585","author":"Li","year":"2022","journal-title":"Appl. Surf. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1016\/j.carbon.2015.09.001","article-title":"3D network graphene interlayer for excellent interlaminar toughness and strength in fiber reinforced composites","volume":"95","author":"Jia","year":"2015","journal-title":"Carbon"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1400110","DOI":"10.1002\/admi.201400110","article-title":"Carbon Nanotube Pullout, Interfacial Properties, and Toughening in Ceramic Nanocomposites: Mechanistic Insights from Single Fiber Pullout Analysis","volume":"2","author":"Kessman","year":"2014","journal-title":"Adv. Mater. Interfaces"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"7352","DOI":"10.1021\/acsami.7b16136","article-title":"\u201cBrick-and-mortar\u201d nanostructured interphase for glass-fiber-reinforced polymer composites","volume":"10","author":"Sernicola","year":"2018","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Doineau, E., Cathala, B., Benezet, J.C., Bras, J., and Le Moigne, N. (2021). European polysaccharide, Development of bio-inspired hierarchical fibres to tailor the fibre\/matrix interphase in (bio) composites. Polymers, 13.","DOI":"10.3390\/polym13050804"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"831","DOI":"10.1016\/j.msea.2012.10.046","article-title":"Increasing mechanical strength retention rate of car-bon\/carbon composites after graphitization by grafting straight carbon nanotubes radially onto carbon fibers","volume":"560","author":"Song","year":"2013","journal-title":"Mater. Sci. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"139839","DOI":"10.1016\/j.msea.2020.139839","article-title":"Effect of Al2O3 coating thickness on microstructural characterization and mechanical properties of continuous carbon fiber reinforced aluminum matrix composites","volume":"793","author":"Zhu","year":"2020","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/j.compscitech.2016.07.009","article-title":"Electrophoretic deposition of graphene oxide on continuous carbon fibers for reinforcement of both tensile and interfacial strength","volume":"135","author":"Wang","year":"2016","journal-title":"Compos. Sci. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1038\/nmat906","article-title":"Nanostructured artificial nacre","volume":"2","author":"Tang","year":"2003","journal-title":"Nat. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"108336","DOI":"10.1016\/j.compscitech.2020.108336","article-title":"Establishment of multistage gradient modulus intermediate layer between fiber and matrix via designing double \u201crigid-flexible\u201d structure to improve interfacial and mechanical properties of carbon fiber\/resin composites","volume":"200","author":"Feng","year":"2020","journal-title":"Compos. Sci. Technol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1900970","DOI":"10.1002\/admi.201900970","article-title":"Synergistic strengthening and toughening the interphase of composites by constructing alternating \u201crigid-and-soft\u201d structure on carbon fiber surface","volume":"6","author":"Wu","year":"2019","journal-title":"Adv. Mater. Interfaces"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"12566","DOI":"10.1021\/am502490j","article-title":"Silica-decorated polypropylene microfiltration mem-branes with a mussel-inspired intermediate layer for oil-in-water emulsion separation","volume":"6","author":"Yang","year":"2014","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"7581","DOI":"10.1002\/adma.201403259","article-title":"Air\/Water Interfacial Formation of Freestanding, Stimuli-Responsive, Self-Healing Catecholamine Janus-Faced Microfilms","volume":"26","author":"Hong","year":"2014","journal-title":"Adv. Mater."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"143929","DOI":"10.1016\/j.apsusc.2019.143929","article-title":"Multi-scale structure construction of carbon fiber surface by electrophoretic deposition and electropolymerization to enhance the interfacial strength of epoxy resin composites","volume":"499","author":"Sun","year":"2020","journal-title":"Appl. Surf. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1601192","DOI":"10.1002\/admi.201601192","article-title":"Versatile Surface Modification Using Polydopamine and Related Polycatecholamines: Chemistry, Structure, and Applications","volume":"4","author":"Barclay","year":"2017","journal-title":"Adv. Mater. Interfaces"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5638","DOI":"10.1021\/acssuschemeng.8b03590","article-title":"Bioinspired Modification via Green Synthesis of Mussel-Inspired Nanoparticles on Carbon Fiber Surface for Advanced Composite Materials","volume":"7","author":"Gao","year":"2018","journal-title":"ACS Sustain. Chem. Eng."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"145238","DOI":"10.1016\/j.apsusc.2019.145238","article-title":"Superior and versatile interface transition layer with a sand-wich-like multiscale rigid-soft dual-locked structure for high performance composites","volume":"508","author":"Jin","year":"2020","journal-title":"Appl. Surf. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"149162","DOI":"10.1016\/j.apsusc.2021.149162","article-title":"Effects of chain length of polyether amine on interfacial adhesion of carbon fiber\/epoxy composite in the absence or presence of polydopamine bridging platform","volume":"547","author":"Wu","year":"2021","journal-title":"Appl. Surf. Sci."},{"key":"ref_23","first-page":"e1525","article-title":"Strengthening and Modulating Interphases in Carbon Fiber\/Epoxy Composites by Grafting Dendritic Polyetheramine With Different Molecular Weights Onto Carbon Fiber","volume":"40","author":"Han","year":"2018","journal-title":"Polym. Compos."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4412","DOI":"10.1021\/acssuschemeng.8b00290","article-title":"Codepositing Mussel-Inspired Nanohybrids onto One-Dimensional Fibers under \u201cGreen\u201d Conditions for Significantly Enhanced Surface\/Interfacial Properties","volume":"6","author":"Yang","year":"2018","journal-title":"ACS Sustain. Chem. Eng."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.compositesb.2018.07.037","article-title":"Polydopamine induced natural fiber surface functionalization: A way towards flame retardancy of flax\/poly(lactic acid) biocomposites","volume":"154","author":"Zhang","year":"2018","journal-title":"Compos. Part B Eng."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1016\/j.apsusc.2019.04.184","article-title":"Fe3O4\/graphene modified waterborne polyimide sizing agent for high modulus carbon fiber","volume":"485","author":"Hao","year":"2019","journal-title":"Appl. Surf. Sci."},{"key":"ref_27","first-page":"1639","article-title":"Improved interfacial bonding strength of silicone rubber\/carbon fiber modified by dopamine","volume":"11","author":"Gu","year":"2022","journal-title":"Polym. Compos."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1016\/j.carbon.2010.01.029","article-title":"Combined XPS and TPD study of oxygen-functionalized carbon nanofibers grown on sintered metal fibers","volume":"48","author":"Rosenthal","year":"2010","journal-title":"Carbon"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.compscitech.2016.11.013","article-title":"Stepwise growth of melamine-based dendrimers onto carbon fibers and the effects on interfacial properties of epoxy composites","volume":"138","author":"Zhao","year":"2016","journal-title":"Compos. Sci. Technol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1016\/j.compscitech.2015.04.011","article-title":"Improving the interfacial properties of carbon fiber-reinforced epoxy composites by grafting of branched polyethyleneimine on carbon fiber surface in supercritical methanol","volume":"114","author":"Ma","year":"2015","journal-title":"Compos. Sci. Technol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"128085","DOI":"10.1016\/j.colsurfa.2021.128085","article-title":"A mussel-inspired strategy for CNT\/carbon fiber reinforced epoxy composite by hierarchical surface modification","volume":"635","author":"Xu","year":"2021","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1016\/j.cej.2017.03.087","article-title":"Zinc ions enhanced nacre-like chitosan\/graphene oxide composite film with superior mechanical and shape memory properties","volume":"321","author":"Liu","year":"2017","journal-title":"Chem. Eng. J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"807","DOI":"10.1016\/j.carbon.2016.10.067","article-title":"Super-tough artificial nacre based on graphene oxide via synergistic interface interactions of \u03c0-\u03c0 stacking and hydrogen bonding","volume":"111","author":"Song","year":"2017","journal-title":"Carbon"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2397","DOI":"10.1016\/j.compstruct.2012.03.014","article-title":"Improvements in mechanical and thermo-mechanical properties of e-glass\/epoxy composites using amino functionalized MWCNTs","volume":"94","author":"Rahman","year":"2012","journal-title":"Compos. Struct."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.compositesa.2014.04.023","article-title":"Mechanical properties of epoxy composites filled with silane-functionalized graphene oxide","volume":"64","author":"Wan","year":"2014","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"132449","DOI":"10.1016\/j.cej.2021.132449","article-title":"Mussel-tailored carbon fiber\/carbon nanotubes interface for elevated interfacial properties of carbon fiber\/epoxy composites","volume":"429","author":"Wu","year":"2021","journal-title":"Chem. Eng. J."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"108296","DOI":"10.1016\/j.compscitech.2020.108296","article-title":"Layer-by-layer assembled nacre-like polyether amine\/GO hierarchical structure on carbon fiber surface toward composites with excellent interfacial strength and toughness","volume":"198","author":"Wu","year":"2020","journal-title":"Compos. Sci. Technol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"626","DOI":"10.1016\/j.compositesa.2018.02.003","article-title":"Polydopamine as sizing on carbon fiber surfaces for enhancement of epoxy laminated composites","volume":"107","author":"Han","year":"2018","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"112075","DOI":"10.1016\/j.compstruct.2020.112075","article-title":"Constructing a simple anti-sandwich structure on carbon fiber surface for simultaneously strengthening and toughening the interphase of epoxy composites","volume":"240","author":"Wu","year":"2020","journal-title":"Compos. Struct."}],"container-title":["Nanomaterials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-4991\/12\/17\/3056\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:22:38Z","timestamp":1760142158000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-4991\/12\/17\/3056"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9,2]]},"references-count":39,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2022,9]]}},"alternative-id":["nano12173056"],"URL":"https:\/\/doi.org\/10.3390\/nano12173056","relation":{},"ISSN":["2079-4991"],"issn-type":[{"value":"2079-4991","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9,2]]}}}