Synthesis and Photophysical Properties of Novel Triphenylamide-Based Hyperbranched Conjugated Polymer

摘要

The hyperbranched conjugated polymers have attracted much attention in recent decades due to their excellent thermally stability, good solubility, extraordinary photophysical properties, and so on. On account of their wide applications in organic light-emitting diodes, organic photovoltaic cells, organic field-effect transistors, etc., the controlling of photophysical properties about hyperbranched polymers becomes an important subject. In this work, a novel triphenylamide-based hyperbranched conjugated polymer (HPTPA-BTz) and its model compound (TPA-BTz) as shown in Figure 1 (left) are synthesized by palladium-catalyzed Suzuki-cross coupling reaction. The structures of HPTPA-BTz and TPA-BTz are characterized by ~1H-NMR, FT-IR and GPC. The resulting polymer can be easily solved in organic common solvents such as CHCl_3 and THF. The photophysical properties are investigated by UV-vis, steady and transient fluorescent spectra. Although the same emission maxima (524nm) are obtained in the tetrahydrofuran solution, the fluorescence lifetime is decreased from 4.695ns of TPA-BTz to 3.075ns of HPTPA-BTz as shown in Figure 1 (right). The authors greatly acknowledge the financial supports from the National Natural Science Foundation of China (NSFC, U1304212 and 21274133).