Electrospinning is a simple technique used to fabricate polymeric nano-fibrous membranes.These nano-fibers have found a wide range of valuable applications in the biomedical field.However,it has not been utilized with...Electrospinning is a simple technique used to fabricate polymeric nano-fibrous membranes.These nano-fibers have found a wide range of valuable applications in the biomedical field.However,it has not been utilized with solid high explosives yet.Herein,the electrospinning technique has been used to fabricate polystyrene(PS)/1,3,5-trinitro-1,3,5-triazinane(RDX)composite nanofibers.The governed electrospinning parameters,voltage,distance from the collector,flow rate,mandrel rotating speed,time,and solution concentration,that greatly affect the morphology of the obtained nanofibers were optimized.The fabricated PS/RDX nano-fibers were characterized using scanning electron microscopy(SEM),X-ray diffractometer(XRD),and Fourier Transform Infrared(FTIR)spectroscopy.The impact and friction sensitivities of PS/RDX were also measured.The thermal behavior of the prepared composite and the pure materials were studied by the thermal gravimetric analysis technique(TGA).SEM results proved the fabrication of PS/RDX fibers in the nano-size via electrospinning.FTIR spectroscopy confirmed the existence of the characteristic functional groups of both PS and RDX in the composite nano-fibers.XRD sharp peaks showed the conversion of amorphous PS into crystalline shape via electrospinning and also confirmed the formation of PS/RDX composite.The PS fibers absorbed the heat and increased the onset decomposition of the pure RDX from 181.5 to 200.7℃in the case of PS/RDX fibers.Interestingly,PS/RDX nano-fibers showed the relatively low impact and friction sensitivities of 100 J and 360 N respectively.These results could introduce PS/RDX nanofibrous composite in the field of explosives detection with high levels of safety.展开更多
Different-sized hollow SiO2 spheres of 249–1348 nm in diameter were successfully prepared by using Na2SiO3 as the precursor and using polystyrene and polystyrene-methyl acrylic acid latexes as the templates. The diam...Different-sized hollow SiO2 spheres of 249–1348 nm in diameter were successfully prepared by using Na2SiO3 as the precursor and using polystyrene and polystyrene-methyl acrylic acid latexes as the templates. The diameter and shell thickness of the hollow SiO2 spheres increase with increasing the latex template diameter at a given mass ratio of SiO2 to latex template. The diameter and shell thickness of the hollow SiO2 spheres also increase with increasing the mass ratios of SiO2 to latex template. The presence of carboxylic acid groups on the surfaces of polystyrene-methyl acrylic acid latex templates favors the formation of dense and uniform SiO2 shells. The hollow SiO2 sphere is constructed by mesoporous shell with large specific surface area. When glyphosate is used as a release model chemical, glyphosate release rate is tuned by varying the shell thickness.展开更多
文摘Electrospinning is a simple technique used to fabricate polymeric nano-fibrous membranes.These nano-fibers have found a wide range of valuable applications in the biomedical field.However,it has not been utilized with solid high explosives yet.Herein,the electrospinning technique has been used to fabricate polystyrene(PS)/1,3,5-trinitro-1,3,5-triazinane(RDX)composite nanofibers.The governed electrospinning parameters,voltage,distance from the collector,flow rate,mandrel rotating speed,time,and solution concentration,that greatly affect the morphology of the obtained nanofibers were optimized.The fabricated PS/RDX nano-fibers were characterized using scanning electron microscopy(SEM),X-ray diffractometer(XRD),and Fourier Transform Infrared(FTIR)spectroscopy.The impact and friction sensitivities of PS/RDX were also measured.The thermal behavior of the prepared composite and the pure materials were studied by the thermal gravimetric analysis technique(TGA).SEM results proved the fabrication of PS/RDX fibers in the nano-size via electrospinning.FTIR spectroscopy confirmed the existence of the characteristic functional groups of both PS and RDX in the composite nano-fibers.XRD sharp peaks showed the conversion of amorphous PS into crystalline shape via electrospinning and also confirmed the formation of PS/RDX composite.The PS fibers absorbed the heat and increased the onset decomposition of the pure RDX from 181.5 to 200.7℃in the case of PS/RDX fibers.Interestingly,PS/RDX nano-fibers showed the relatively low impact and friction sensitivities of 100 J and 360 N respectively.These results could introduce PS/RDX nanofibrous composite in the field of explosives detection with high levels of safety.
基金Projects (11KJB530002, CX10B-259Z) supported by Research Funds from Jiangsu Provincial Department of Education, ChinaProject (10zxfk35) supported by Sichuan Province Nonmetallic Composites and Functional Materials Key Laboratory Project, China
文摘Different-sized hollow SiO2 spheres of 249–1348 nm in diameter were successfully prepared by using Na2SiO3 as the precursor and using polystyrene and polystyrene-methyl acrylic acid latexes as the templates. The diameter and shell thickness of the hollow SiO2 spheres increase with increasing the latex template diameter at a given mass ratio of SiO2 to latex template. The diameter and shell thickness of the hollow SiO2 spheres also increase with increasing the mass ratios of SiO2 to latex template. The presence of carboxylic acid groups on the surfaces of polystyrene-methyl acrylic acid latex templates favors the formation of dense and uniform SiO2 shells. The hollow SiO2 sphere is constructed by mesoporous shell with large specific surface area. When glyphosate is used as a release model chemical, glyphosate release rate is tuned by varying the shell thickness.
