ORGANIC DONOR-PI-ACCEPTOR SALTS - A NEW-TYPE OF PROBE FOR MONITORING PHOTOPOLYMERIZATION PROCESSES

Organic salts consisting of an organic cation, composed of an alkylate d pyridinium ion linked to a dimethylamino group by a jr-system, and a n inorganic anion were incorporated in polymeric networks formed by ph otopolymerization of dimethacrylates of different size and polarity. T he response of the probe's emission to changes in its environment duri ng photopolymerization was determined and compared with the response o f 4-(dimethylamino)-4'-nitrostilbene, a typical charge transfer probe. Emissions in solvents of low viscosity but with different polarities are also reported. A mechanism to explain the probe's response is pres ented.