Application of Poly(biscyanopropylsiloxane) in Surface Acoustic Wave Sensors to Organophosphorus Chemical Warfare Agent Detection

The paper investigates applicability of poly(biscyanopropylsiloxane) (PCNPS) as a chemosensitive coating agent for surface acoustic wave (SAW) sensors to organophosphorus chemical warfare agent (CWA) detection. The polymer was deposited on SAW resonators by vacuum evaporation. Sensor sensitivity to organophosphorus compounds was investigated using dimethyl methylphosphonate (DMMP) vapors via sensor frequency and amplitude response testing. Also, other substances from the set (heptane, triethylamine (TEA), acetonitrile (ACN), dimethylformamide (DMF), n-butanol) were tested as potential interference factors. Excellent sensitivity of frequency signal was achieved (about 500Hz/ppm) against DMMP. Sensitivity toward the remaining test substances, except for DMF, was comparable to the noise level. Low glass transition temperature of the PCNPS phase, corresponding to good dynamic properties of the sensors, indicates suitability of this phase for application in SAW sensors.