<title>Perchloroethylene detection in air: a comparative study using polymer sensor elements and catalyst/sensor systems</title>

Abstract

In a first approach perchloroethylene (C2C14 or "PER") was determined quantitatively in air by monitoring mass and temperature changes of polymer-coated quartz microbalance and calorimetric transducers. The different equilibrium and time-dependent sensor responses result from reversible interactions between perchioroethylene molecules from the gas phase and chemically sensitive polymers based upon modified siloxanes.In a second approach, we determined PER by applying pattern recognition methods to evaluate data from catalyst/electrochemical sensor-systems. Here, PER is decomposed at a heated catalytic filament. The molecular fragments are detected subsequently by an electrochemical or semiconductor gas sensor. The quantitative determination of perchioroethylene in air in the ppm-range ist possible by applying mathematical procedures of pattern recognition. Finally, a comparative discussion of the different transducer and evaluation principles is given for specific applications.