期刊
JOURNAL OF PHYSICAL CHEMISTRY C
卷 116, 期 28, 页码 14737-14747出版社
AMER CHEMICAL SOC
DOI: 10.1021/jp303077f
关键词
-
资金
- U.S. Army Research Office [W911NF-10-1-0072]
- U.S. Air Force Office of Scientific Research [FAA9550-09-1-0163]
- Office of Naval Research [N00014-11-1-0418]
- [DEFG02-91ER45439]
Nanotechnology has brought a great deal of excitement to research in energetic materials(EMs). Nanoparticle EMs have high densities of stored energy and the potential for multifunctionality. Here we discuss research on fundamental mechanisms of initation and ignition of EM with Al or B fuel nanoparticles and Teflon(AF) or nitrocellulose (NC) oxidizer. Polybutadiene (PB) was also used as an inert. The thin-film samples were confined between two windows and were activated by flash-heating the metal nanoparticles with picosecond laser pulses. Reactions of isolated nanoparticles with their surroundings were studied by measuring ablation thresholds. A shock-induced polymer dissociation model was needed to explain the growth of the reaction volume surrounding a flash-heated fuel particle. Thicker oxide passivation layers confined the nanoparticle allowing the pressure to build up to higher values during flash-heating. Initiation, as the onset of chemical reactivity, was probed using time-resolved Raman or infrared to monitor disappearance of nitrato (ONO2) of NC or CF2, CF3,or CFO of Teflon(AF). Ignition, the onset of energy-releasing processes, was studied by analyzing time-dependent spectra of emission bursts. In flash-heated Al/Teflon, initiation occurs in similar to 50 ps and ignition occurs in similar to 100 ps. In B/Teflon, ignition occurs in similar to 200 ps. Transient opacity measurements of Al/Teflon suggest that chemical reactivity beyond the initial exothermic formation of AlF occurs within similar to 5 ns.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据