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作者： Kai Wang, Yimin Luo, Shuo Huang, Hongbin Yang, Bin Liu andMingfeng Wang

School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore

 

摘要：Well-defined 1,4-diketo-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole (DTDPP) labeled polycaprolactones (PCL) with different chain lengths were synthesized and characterized. The effect of polymer chain lengths on the optical properties of DTDPP in solid states was studied by UV-Vis absorption spectroscopy as well as steady-state and dynamic fluorescence spectroscopies. Our results indicate that when the PCL side chain is extended to a certain length, the intermolecular aggregation of DTDPP units can be reduced significantly due to segregation effect of PCL. This approach offers a new facile strategy to address the common problem of aggregation-caused quenching existing in organic fluorophores. These highly fluorescent biodegradable PCL polymers may find broad biomedical applications such as fluorescence-based bioimaging and tissue engineering.

 

關鍵詞：aggregation; biodegradable;diketopyrrolopyrrole;fluorescence;polycaprolactone;ring-opening polymerization