| International terrorism, homeland security, and the remains of landmines throughout the world have increased interest in the detection of explosive materials. Non-contact methods for sensing explosives in the field are necessary worldwide. 2, 4-Dinitrotoluene (DNT) is model for 2, 4, 6-trinitrotoluene (TNT), a readily-available explosive. The focus of this project is to make a sensor based on dendrons (tree-like polymers on surfaces) that can detect DNT. In the work described here, a modification of the literature synthesis of melamine dendrons that was synthesized and characterized by Simanek, Shantz and coworkers was used. The sensor design included a high surface area substrate made of mesoporous silicate (m-SiO2) films and solids. The dendrons were built on the substrates via an iterative method and a phenol added through an imine linkage. Calculations indicated that G1-imine dendrons should have greater affinity for DNT than G1 alone based on H-bonding interactions of the DNT nitro group oxygens with the phenol proton. The solid dendronic materials were analyzed using thermogravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR) before and after exposure to DNT. Films were characterized by Ultraviolet Spectroscopy (UV). |
