Synthesis of porphyrin end-capped water-soluble poly(phenylene ethynylene) and study of its optical properties

A novel Porphyrin End-Capped poly(phenylene ethynylene) (P-PPE) was synthesized by palladium-catalyzed cross-coupling reaction. Porphyrin was successfully introduced to the polymer backbone, which was confirmed by 1H NMR, UV–Vis and Fluorescence spectroscopy. The degree of polymerization of P-PPE was characterized by both 1H NMR and GPC analysis. UV–Vis absorption and fluorescence studies in organic solvent indicate that there is significant energy transfer between the PPE backbone and the terminal porphyrin end group, and the PPE backbone works as an antenna transferring photo energy to ZnTPP terminal. The aggregation state of P-PPE in water was also investigated by UV–Vis and fluorescence studies.