DESIGN AND SYNTHESIS OF METAL ION-RECOGNITION-INDUCED CONJUGATED POLYMERS - AN APPROACH TO METAL-ION SENSORY MATERIALS

The synthesis and metal ion responsive properties of two 2,2'-bipyridy l-phenylene-vinylene-based polymers is reported. These polymers are de signed to be partially conjugated in their metal-free state and fully conjugated when exposed to metal ions so that the ion-induced conjugat ion enhancement can be transduced into a measurable signal. It is foun d that these polymers exhibit highly ionochromic effects with a wide v ariety of transition and main group metal ions excluding metal ions of the alkali and alkaline earth groups. For instance, both absorption a nd fluorescence emission bands of the polymers upon exposure to metal ions can be red-shifted up to 120 nm, depending on the metal ions pres ent and the polymers used.