Composites based on ultradispersed polytetrafluoroethylene and intercalated graphite oxide compounds with dodecahydro-closo-dodecaborates and methods of their fabrication have been developed. The fabricated composites...Composites based on ultradispersed polytetrafluoroethylene and intercalated graphite oxide compounds with dodecahydro-closo-dodecaborates and methods of their fabrication have been developed. The fabricated composites have been characterized using XRD analysis, and optical microscopy. These composites are distinguished with completeness of their combustion, since the combustion products comprise gaseous boron fluorine-containing compounds of boron, boron trifluoride (BF3), and boron oxyfluoride ((BOF)3). Besides, these composites are characterized with increased energy capacity as compared to purely oxygen-containing compounds, since the heat of formation of boron fluorine-containing compounds is higher than that of boron oxide. Introduction of ultradispersed polytetrafluoroethylene imparts composites with hydrophobicity, thus improving their functioning properties.展开更多
Graphite oxide, a pseudo-two-dimensional solid in bulk form, was synthesized from natural graphite powder by oxidization with KMnO4 in concentrated H2SO4. The poly(vinyl acetate)-intercalated graphite oxide nano-compo...Graphite oxide, a pseudo-two-dimensional solid in bulk form, was synthesized from natural graphite powder by oxidization with KMnO4 in concentrated H2SO4. The poly(vinyl acetate)-intercalated graphite oxide nano-composite was prepared by an in situ intercalative polymerization reaction, in which n-octanol-graphite oxide intercalation compounds were first obtained, vinyl acetate monomer was then dispersed into the interlayer of modified graphite oxide, followed by thermal polymerization of the monomer. It was experimentally shown that the c-axis space of poly(vinyl acetate)-intercalated graphite oxide was increased to 0.115 nm, which suggested there existed a monolayer of poly(vinyl acetate) chain between the layers of graphite oxide. The nanocomposite was also characterized with thermal analysis and FT-IR spectrometry.展开更多
An intercalative composite of graphite oxide （GO） as host intercalated by an object of TiO2 nanoparticles was obtained at low temperature by mixing GO with Ti（SO4）2 solution, and by another object of Ti2O3 while m...An intercalative composite of graphite oxide （GO） as host intercalated by an object of TiO2 nanoparticles was obtained at low temperature by mixing GO with Ti（SO4）2 solution, and by another object of Ti2O3 while mixing with TiCl4 ethanol solution. Microstructures of the GO and its intercalative composites at different C/Ti ratio were studied by XRD, SEM, AFM and FF-IR, and the evolution of these lamellar structures was studied based on the temperature change. The photocatalytic activity of the intercalative composites was characterized according to the degradation of methyl orange. The intercalative composite formed by Ti（SO4）2 solution presents an excellent photocatalytic reactivity, while that formed by TiCl4 presents no observablly photocatalytic reactivity. The electric conductivity variation of different composites was checked, in order to investigate the role of the possible electron transfer between the graphite layer and TiO2 nanocrystal during TiO2 excited by UV light irradiation.展开更多
以攀枝花天然鳞片石墨为原料,高锰酸钾和双氧水为氧化剂,硝酸、硫酸和高氯酸作为插层剂,制备膨胀石墨。实验发现较佳的膨化温度为950℃,并以此温度制备膨胀石墨。结果显示,以双氧水和硫酸制备的膨胀石墨其膨胀容积为130.97-221.80 m L/g...以攀枝花天然鳞片石墨为原料,高锰酸钾和双氧水为氧化剂,硝酸、硫酸和高氯酸作为插层剂,制备膨胀石墨。实验发现较佳的膨化温度为950℃,并以此温度制备膨胀石墨。结果显示,以双氧水和硫酸制备的膨胀石墨其膨胀容积为130.97-221.80 m L/g;以高锰酸钾和硝酸制备的可膨胀石墨其膨胀容积为150.65-247.19 m L/g;以高锰酸钾和高氯酸制备的膨胀石墨,在干燥温度和时间分别为50℃和4-5 h时膨胀容积可达300 m L/g以上。实验还采用XRD和SEM对制备的膨胀石墨结构和形貌进行分析,测试结果发现膨胀石墨的结构完整,可用于进一步制备复合相变材料。展开更多
文摘Composites based on ultradispersed polytetrafluoroethylene and intercalated graphite oxide compounds with dodecahydro-closo-dodecaborates and methods of their fabrication have been developed. The fabricated composites have been characterized using XRD analysis, and optical microscopy. These composites are distinguished with completeness of their combustion, since the combustion products comprise gaseous boron fluorine-containing compounds of boron, boron trifluoride (BF3), and boron oxyfluoride ((BOF)3). Besides, these composites are characterized with increased energy capacity as compared to purely oxygen-containing compounds, since the heat of formation of boron fluorine-containing compounds is higher than that of boron oxide. Introduction of ultradispersed polytetrafluoroethylene imparts composites with hydrophobicity, thus improving their functioning properties.
基金Financial support from Key Project of The National Natural Science Foundation of China (No. 59836230) is gratefully acknowledged.
文摘Graphite oxide, a pseudo-two-dimensional solid in bulk form, was synthesized from natural graphite powder by oxidization with KMnO4 in concentrated H2SO4. The poly(vinyl acetate)-intercalated graphite oxide nano-composite was prepared by an in situ intercalative polymerization reaction, in which n-octanol-graphite oxide intercalation compounds were first obtained, vinyl acetate monomer was then dispersed into the interlayer of modified graphite oxide, followed by thermal polymerization of the monomer. It was experimentally shown that the c-axis space of poly(vinyl acetate)-intercalated graphite oxide was increased to 0.115 nm, which suggested there existed a monolayer of poly(vinyl acetate) chain between the layers of graphite oxide. The nanocomposite was also characterized with thermal analysis and FT-IR spectrometry.
基金Funded by The National Natural Science Foundation of China(No.50572070 and No.50672066)
文摘An intercalative composite of graphite oxide （GO） as host intercalated by an object of TiO2 nanoparticles was obtained at low temperature by mixing GO with Ti（SO4）2 solution, and by another object of Ti2O3 while mixing with TiCl4 ethanol solution. Microstructures of the GO and its intercalative composites at different C/Ti ratio were studied by XRD, SEM, AFM and FF-IR, and the evolution of these lamellar structures was studied based on the temperature change. The photocatalytic activity of the intercalative composites was characterized according to the degradation of methyl orange. The intercalative composite formed by Ti（SO4）2 solution presents an excellent photocatalytic reactivity, while that formed by TiCl4 presents no observablly photocatalytic reactivity. The electric conductivity variation of different composites was checked, in order to investigate the role of the possible electron transfer between the graphite layer and TiO2 nanocrystal during TiO2 excited by UV light irradiation.
文摘以攀枝花天然鳞片石墨为原料,高锰酸钾和双氧水为氧化剂,硝酸、硫酸和高氯酸作为插层剂,制备膨胀石墨。实验发现较佳的膨化温度为950℃,并以此温度制备膨胀石墨。结果显示,以双氧水和硫酸制备的膨胀石墨其膨胀容积为130.97-221.80 m L/g;以高锰酸钾和硝酸制备的可膨胀石墨其膨胀容积为150.65-247.19 m L/g;以高锰酸钾和高氯酸制备的膨胀石墨,在干燥温度和时间分别为50℃和4-5 h时膨胀容积可达300 m L/g以上。实验还采用XRD和SEM对制备的膨胀石墨结构和形貌进行分析,测试结果发现膨胀石墨的结构完整,可用于进一步制备复合相变材料。
