Direct Detection of RDX Vapor Using a Conjugated Polymer Network
摘要:
1,3,5-Trinitroperhydro-1,3,5-triazine (RDX) is a principal component of plastic explosives used in acts of terrorism and within improvised explosive devices, among others. Approaches to detect RDX compatible with remote, "stand-off" sampling that do not require preconcentration strategies, such as the swabs commonly employed in airports, will benefit military and civilian security. Such detection remains a significant challenge because RDX is 10(3) less volatile than 1,3,5-trinitrotoluene (TNT), corresponding to a parts-pertrillion vapor pressure under ambient conditions. Therefore, while fluorescence quenching of conjugated polymers is sufficiently sensitive to detect TNT vapors, RDX vapor detection is undemonstrated. Here we report a cross-linked phenylene vinylene polymer network whose fluorscence is quenched by trace amounts of RDX introduced from solution or the vapor phase. Fluorescence quenching is reduced, but remains significant, when partially degraded RDX is employed, suggesting that the polymer responds to RDX itself. The polymer network also responds to TNT and PETN similarly introduced from solution or the vapor phase. Pure solvents, volatile amines, and the outgassed vapors from lipstick or sunscreen do not quench polymer fluorscence. The established success of TNT sensors based on fluorescence quenching makes this a material of interest for real-world explosive sensors and will motivate further interest in cross-linked polymers and framework materials for sensing applicaitons.
CROSS-LINKED POLYMER NETWORKS AND METHODS OF MAKING AND USING SAME
申请人:CORNELL UNIVERSITY
公开号:US20160002421A1
公开(公告)日:2016-01-07
Cross-linked polymer networks that are at least partially conjugated (e.g., phenylene vinylene polymer networks). The cross-linked polymer networks may be thin-films disposed on a substrate. The cross-linked polymer network may be covalently bonded to the substrate. The cross-linked polymer networks can be used, for example, in methods of detecting explosives (e.g., RDX (cyclotrimethylenetrinitramine)) and degradation products thereof.
The semi-hydrogenation of terminalalkynes is successfully achieved with NaBH4 catalyzed by recyclable palladium nanowires (PdNWs) under ambient conditions. With only 0.32 mol % of catalyst loading, the reaction gives the hydrogenated products with up to 98 % overall yields, in which 97 % are semi-hydrogenated products. The method expands the application of metal nanomaterials in organic syntheses