Surface of polyacrylonitrile (PAN)-based carbon fibers was modified by electrochemical oxidation. The modification effect on carbon fibers surface was explored using atomic force microscopy (AFM), X-ray photoelectron ...Surface of polyacrylonitrile (PAN)-based carbon fibers was modified by electrochemical oxidation. The modification effect on carbon fibers surface was explored using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Results showed that on the modified surface of carbon fibers, the carbon contents decreased by 9.7% and the oxygen and nitrogen contents increased by 53.8% and 7.5 times, respectively. The surface roughness and the hydroxyl and carbonyl contents also increased. The surface orientation index was reduced by 1.5% which decreased tensile strength of carbon fibers by 8.1%, and the microcrystalline dimension also decreased which increased the active sites of carbon fiber surface by 78%. The physical and chemical properties of carbon fibers surface were modified through the electrochemical oxidative method, which improved the cohesiveness between the fibers and resin matrix and increased the interlaminar shear strength (ILSS) of carbon fibers reinforced epoxy composite (CFRP) over 20%.展开更多
Interconnected Ni(OH)_(2)nanoflakes and polyether amine(PEA)were deposited on carbon fiber tows via a facial and effective process of chemical bath deposition and dip coating.Based on this,a win–win benefit of simult...Interconnected Ni(OH)_(2)nanoflakes and polyether amine(PEA)were deposited on carbon fiber tows via a facial and effective process of chemical bath deposition and dip coating.Based on this,a win–win benefit of simultaneously improvements in interfacial shear strength(IFSS)of carbon fiber/epoxy composites and the electrochemical activity has been achieved.Compared with CF and CF-Ni(OH)_(2)composites,the IFSS of CF-Ni(OH)_(2)-PEA/epoxy composite respectively increased 7.9%and 45.4%,which was put down to the covalent bonding of Ni(OH)_(2)-PEA coating with fiber and epoxy matrix,as well as the effective stress transfer by the uniform honeycomb structure of Ni(OH)_(2).In aqueous KOH electrolyte,the CF-Ni(OH)_(2)-PEA electrode presented the maximum specific capacitance of 689.98 F·g^(-1)at 5 m V·s^(-1),572.28 F·g^(-1)at a current density of 0.5 A·g^(-1)due to the strong adhesion of carbon fiber with Ni(OH)_(2)by PEA,the reservation of the threedimensional hollow honeycomb structure of Ni(OH)_(2)for easy ion-transport and–NH_(2)functional groups from PEA for providing more active sites.The excellent performance of CF-Ni(OH)_(2)-PEA reinforcement demonstrates its promising potential for application in high performance composites with integrated structure and function,which shows great advantages in various fields of aerospace,energy,electronics,automobile,civil engineering,sports,etc.展开更多
基金This work was financially supported by the National Nat-ural Science Foundation of China(Grant No.50172004 and 50333070).
文摘Surface of polyacrylonitrile (PAN)-based carbon fibers was modified by electrochemical oxidation. The modification effect on carbon fibers surface was explored using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Results showed that on the modified surface of carbon fibers, the carbon contents decreased by 9.7% and the oxygen and nitrogen contents increased by 53.8% and 7.5 times, respectively. The surface roughness and the hydroxyl and carbonyl contents also increased. The surface orientation index was reduced by 1.5% which decreased tensile strength of carbon fibers by 8.1%, and the microcrystalline dimension also decreased which increased the active sites of carbon fiber surface by 78%. The physical and chemical properties of carbon fibers surface were modified through the electrochemical oxidative method, which improved the cohesiveness between the fibers and resin matrix and increased the interlaminar shear strength (ILSS) of carbon fibers reinforced epoxy composite (CFRP) over 20%.
基金supported by the National Natural Science Foundation of China(No.51603169)Natural Science Basic Research Plan in Shaanxi Province of China(No.2017JQ5050)Natural Science Foundation of Shaanxi University of Science&Technology(No.2016QNBJ-12)。
文摘Interconnected Ni(OH)_(2)nanoflakes and polyether amine(PEA)were deposited on carbon fiber tows via a facial and effective process of chemical bath deposition and dip coating.Based on this,a win–win benefit of simultaneously improvements in interfacial shear strength(IFSS)of carbon fiber/epoxy composites and the electrochemical activity has been achieved.Compared with CF and CF-Ni(OH)_(2)composites,the IFSS of CF-Ni(OH)_(2)-PEA/epoxy composite respectively increased 7.9%and 45.4%,which was put down to the covalent bonding of Ni(OH)_(2)-PEA coating with fiber and epoxy matrix,as well as the effective stress transfer by the uniform honeycomb structure of Ni(OH)_(2).In aqueous KOH electrolyte,the CF-Ni(OH)_(2)-PEA electrode presented the maximum specific capacitance of 689.98 F·g^(-1)at 5 m V·s^(-1),572.28 F·g^(-1)at a current density of 0.5 A·g^(-1)due to the strong adhesion of carbon fiber with Ni(OH)_(2)by PEA,the reservation of the threedimensional hollow honeycomb structure of Ni(OH)_(2)for easy ion-transport and–NH_(2)functional groups from PEA for providing more active sites.The excellent performance of CF-Ni(OH)_(2)-PEA reinforcement demonstrates its promising potential for application in high performance composites with integrated structure and function,which shows great advantages in various fields of aerospace,energy,electronics,automobile,civil engineering,sports,etc.