A new method to chemically modify the surface of nanosized-SiO2 was studied in this paper.Nanosized-SiO2 was grafted with hyperbranched poly(amin ester)through one-spot polycondensation between AB2 monomer and active ...A new method to chemically modify the surface of nanosized-SiO2 was studied in this paper.Nanosized-SiO2 was grafted with hyperbranched poly(amin ester)through one-spot polycondensation between AB2 monomer and active hydroxyl on silica surface in present of catalyst.Compared with the results of FTIR and TEM,it is found hyperbranched poly(amin ester)is successfully grafted on the surface of nanosized-SiO2 and the surface properties have been changed with an expected way.The results indicate that nanosized-SiO2 grafted with hyperbranched poly(amin ester)has better dispersion in the ethanol or chloroform than that unmodified.展开更多
A sol-gel synthetic approach combined with an ultrasonic method was utilized to prepare Al/B/Fe2O3 nanothermites.The structure and properties of the prepared nanothermites were characterized by thermogravimetric analy...A sol-gel synthetic approach combined with an ultrasonic method was utilized to prepare Al/B/Fe2O3 nanothermites.The structure and properties of the prepared nanothermites were characterized by thermogravimetric analysis,differential scanning calorimetry,scanning electron microscopy,X-ray diffraction,and an impact sensitivity test.The results verified that the nano-aluminum and the micro-boron were uniformly dispersed in the pores of the iron oxide gel.The heat of the prepared Al/B/Fe2O3 nanothermites was 1.3 times that of the simple physically mixed sample.In addition,the heat of the combustion test showed that these materials were indeed energetic.Small-scale safe experiments also showed that the prepared materials through sol-gel were relatively insensitive to standard impact.展开更多
文摘A new method to chemically modify the surface of nanosized-SiO2 was studied in this paper.Nanosized-SiO2 was grafted with hyperbranched poly(amin ester)through one-spot polycondensation between AB2 monomer and active hydroxyl on silica surface in present of catalyst.Compared with the results of FTIR and TEM,it is found hyperbranched poly(amin ester)is successfully grafted on the surface of nanosized-SiO2 and the surface properties have been changed with an expected way.The results indicate that nanosized-SiO2 grafted with hyperbranched poly(amin ester)has better dispersion in the ethanol or chloroform than that unmodified.
文摘A sol-gel synthetic approach combined with an ultrasonic method was utilized to prepare Al/B/Fe2O3 nanothermites.The structure and properties of the prepared nanothermites were characterized by thermogravimetric analysis,differential scanning calorimetry,scanning electron microscopy,X-ray diffraction,and an impact sensitivity test.The results verified that the nano-aluminum and the micro-boron were uniformly dispersed in the pores of the iron oxide gel.The heat of the prepared Al/B/Fe2O3 nanothermites was 1.3 times that of the simple physically mixed sample.In addition,the heat of the combustion test showed that these materials were indeed energetic.Small-scale safe experiments also showed that the prepared materials through sol-gel were relatively insensitive to standard impact.