Syndiotactic Polystyrene Thin Film as Sensitive Layer for an Optoelectronic Chemical Sensing Device

The performance of an optoelectronic sensor system able to measure the concn. of org. analytes, in aq. environment was analyzed. Syndiotactic polystyrene (sPS) in the nanoporous cryst. d form was here used as sensitive polymeric layer due to its high sorption properties towards chlorinated and arom. compds. In particular, a thin semi-cryst. sPS film with cryst. nanoporous d form was cast on the cleaved end of a std. fiber optic and measurements of reflectivity as the analyte was sorbed by the polymer were carried out allowing online detection of even very low concns. (in the range of few ppm) of chloroform and toluene in water. The refractometer performance was compared with that of a classical resonant quartz-crystal microbalance sensor (QCM), using the same polymer as sensing element.