ON THE FABRICATION PROCESS OF POLYMER-COMPOSITES BASED SENSORS

摘要

The results of investigations of the effects of two organic solvents of preparation, tetrahydrofuran (THF) and 1,1,1,3,3,3 Hexafluoro-2-propanol (HFIP), and of three different electrical geometry of devices on drop-coated poly (methyl-methacrylate)/ carbon black (PMMA/CB) composites gas sensors are presented. Using HFIP solvent, it is possible to obtain a good dispersion of the CB filler in the polymeric matrix but the thcrmodynamic responses of devices to acetone and ethanol vapours are independent from their morphology and from the geometry of devices. The highest sensor responses are to acetone vapor. This behavior could be probably attributed to the higher chemical affinity of less polar molecule as acetone towards PMMA. The filler dispersions, the current-voltage (I/V) characteristics and the stability of devices in the time were also studied and discussed.