Graphene oxide (GO) reduced by Stachys lavandulifolia extract (SLE) was produced and characterised. The anti-corrosion behaviour of epoxy coatings containing GO and rGO nanosheets was investigated. FESEM-EDS, FT-IR, a...Graphene oxide (GO) reduced by Stachys lavandulifolia extract (SLE) was produced and characterised. The anti-corrosion behaviour of epoxy coatings containing GO and rGO nanosheets was investigated. FESEM-EDS, FT-IR, and Raman spectroscopy were used to examine the microstructure and chemical composition of the nanosheets and epoxy coatings. EIS experiment was used to explore the corrosion behaviour of the coatings. The O/C ratio for GO and rGO-SLE was found to be 2.5 and 4.5, indicating a decrease in the carbon content after the reduction of GO, confirming the adsorption of SLE onto the GO nanosheets. The successful reduction of GO in the presence of SLE particles was confirmed by disappearing the C=O peak and a significant decrease in the C-O-C bond intensity. The epoxy/rGO- SLE coatings exhibited the highest double-layer thickness and excellent corrosion resistance compared to neat epoxy and epoxy/GO coatings, emphasizing the significant role of rGO in enhancing the protective performance of epoxy coatings. The highest values for total charge transfer and film resistances and the inhibition efficiency were observed to be 6529 Ω·cm^(2) and 90%, respectively, for the epoxy/rGO-SLE coated steel plate. It was also found that the epoxy/0.15 wt.% rGO-SLE coating demonstrates the best corrosion resistance performance.展开更多
Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological beh...Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological behavior of GNP/epoxy nanocomposites.This study aims to understand how the dispersion of GNPs affects the properties of epoxy nanocomposite and to identify the best dispersion approach for improving mechanical performance.A solvent mixing technique that includes mechanical stirring and ultrasonication was used for producing the nanocomposites.Fourier transform infrared spectroscopy was used to investigate the interaction between GNPs and the epoxy matrix.The measurements of density and moisture content were used to confirm that GNPs were successfully incorporated into the nanocomposite.The findings showed that GNPs are successfully dispersed in the epoxy matrix by combining mechanical stirring and ultrasonication in a single step,producing well-dispersed nanocomposites with improved mechanical properties.Particularly,the nanocomposites at a low GNP loading of 0.1 wt%,demonstrate superior mechanical strength,as shown by increased tensile properties,including improved Young's modulus(1.86 GPa),strength(57.31 MPa),and elongation at break(4.98).The nanocomposite with 0.25 wt%GNP loading performs better,according to the viscoelastic analysis and flexural properties(113.18 MPa).Except for the nanocomposite with a 0.5 wt%GNP loading,which has a higher thermal breakdown temperature,the thermal characteristics do not significantly alter.The effective dispersion of GNPs in the epoxy matrix and low agglomeration is confirmed by the morphological characterization.The findings help with filler selection and identifying the best dispersion approach,which improves mechanical performance.The effective integration of GNPs and their interaction with the epoxy matrix provides the doorway for additional investigation and the development of sophisticated nanocomposites.In fields like aerospace,automotive,and electronics where higher mechanical performance and functionality are required,GNPs'improved mechanical properties and successful dispersion present exciting potential.展开更多
A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfo...A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase separation.After adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,respectively.These improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of CFCs.The G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control laminate.The increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.展开更多
文摘Graphene oxide (GO) reduced by Stachys lavandulifolia extract (SLE) was produced and characterised. The anti-corrosion behaviour of epoxy coatings containing GO and rGO nanosheets was investigated. FESEM-EDS, FT-IR, and Raman spectroscopy were used to examine the microstructure and chemical composition of the nanosheets and epoxy coatings. EIS experiment was used to explore the corrosion behaviour of the coatings. The O/C ratio for GO and rGO-SLE was found to be 2.5 and 4.5, indicating a decrease in the carbon content after the reduction of GO, confirming the adsorption of SLE onto the GO nanosheets. The successful reduction of GO in the presence of SLE particles was confirmed by disappearing the C=O peak and a significant decrease in the C-O-C bond intensity. The epoxy/rGO- SLE coatings exhibited the highest double-layer thickness and excellent corrosion resistance compared to neat epoxy and epoxy/GO coatings, emphasizing the significant role of rGO in enhancing the protective performance of epoxy coatings. The highest values for total charge transfer and film resistances and the inhibition efficiency were observed to be 6529 Ω·cm^(2) and 90%, respectively, for the epoxy/rGO-SLE coated steel plate. It was also found that the epoxy/0.15 wt.% rGO-SLE coating demonstrates the best corrosion resistance performance.
基金the Puncak RM for the project under the grant 6733204-13069 to carry out the experiments。
文摘Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological behavior of GNP/epoxy nanocomposites.This study aims to understand how the dispersion of GNPs affects the properties of epoxy nanocomposite and to identify the best dispersion approach for improving mechanical performance.A solvent mixing technique that includes mechanical stirring and ultrasonication was used for producing the nanocomposites.Fourier transform infrared spectroscopy was used to investigate the interaction between GNPs and the epoxy matrix.The measurements of density and moisture content were used to confirm that GNPs were successfully incorporated into the nanocomposite.The findings showed that GNPs are successfully dispersed in the epoxy matrix by combining mechanical stirring and ultrasonication in a single step,producing well-dispersed nanocomposites with improved mechanical properties.Particularly,the nanocomposites at a low GNP loading of 0.1 wt%,demonstrate superior mechanical strength,as shown by increased tensile properties,including improved Young's modulus(1.86 GPa),strength(57.31 MPa),and elongation at break(4.98).The nanocomposite with 0.25 wt%GNP loading performs better,according to the viscoelastic analysis and flexural properties(113.18 MPa).Except for the nanocomposite with a 0.5 wt%GNP loading,which has a higher thermal breakdown temperature,the thermal characteristics do not significantly alter.The effective dispersion of GNPs in the epoxy matrix and low agglomeration is confirmed by the morphological characterization.The findings help with filler selection and identifying the best dispersion approach,which improves mechanical performance.The effective integration of GNPs and their interaction with the epoxy matrix provides the doorway for additional investigation and the development of sophisticated nanocomposites.In fields like aerospace,automotive,and electronics where higher mechanical performance and functionality are required,GNPs'improved mechanical properties and successful dispersion present exciting potential.
文摘A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase separation.After adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,respectively.These improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of CFCs.The G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control laminate.The increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.
