Chemically Sensitive Polymer Coatings For SH-Surface Acoustic Wave Sensors for the Detection of Benzene in Water

摘要: CHEMICALLY SENSITIVE POLYMER COATINGS FOR SH-SURFACE ACOUSTIC WAVE SENSORS THE DETECTION OF BENZENE IN WATER Robert Lenisa, B.S. Marquette University, 2013 Polymer-coated shear horizontal surface acoustic wave (SH-SAW) sensors are investigated for the detection of benzene in aqueous samples. The SH-SAW using three-layer geometry have a single polymer sensing layer which absorbs analyte and interacts with wave. Several polymers identified as potential improvements over current films based on glass transition temperature Hildebrand solubility parameter. this work include poly (methyl acrylate) (PMA), (butyl (PBA), (ethylene co-vinyl acetate) (PEVA), bisphenol-A (dimethylsiloxane) (BPA PDMS), (hexamethyltrisiloxane) HMTS). spin coated lithium tantalate (LiTaO3) SHSAW dual delay-line device at thicknesses between 0.3 μm 1.0 μm. Each film’s thickness is measured film exposed to multiple concentrations aromatic hydrocarbons benzene, ethylbenzene, toluene, xylenes (BTEX). added mass viscoelastic changes result change center frequency loss device. used determine sensitivity sensor each analyte. BPA PDMS HMTS show larger sensitivities BTEX analytes than PBA, PMA, or PEVA. However, both were observed lose during aging process. It shown that effect can be mitigated by baking after it applied