A Series Of Wide Band-gap Polyphenylene: Synthesis, Design And Properties

Organic luminescence devices got rapid progress with application of flat panel displays. And the organic electroluminescence materials are of considerable interest owing to their attractive characteristics, such as cheap and millions of raw materials, varied molecular structure, flexible display and easy technology for device making, low drive pressure, initiative emission and large area display. As one of tricolor, the blue light fall short of green light in full color display. So the polyphenylene derivatives, the innate blue light emission materials are the materials of intensive researches.In this article, we got a series of derivatives of polyphenylene with different structures and studied the changes of characteristics.There is a lack of blue emission materials, especially deep-blue emission materials in full color display. Co-polymers with two series of biphenyl groups and different conjugated groups show the different band gaps and the different conjugated lengths. The emission light colors of these polymers cover from blue to ultraviolet and the effective conjugated lengths are in the area from two benzenes to twelve benzenes. Wide band-gap materials have the shortages in luminescence efficiency, injection and transport of carriors etc for the special structure. We introduced high luminescence efficient conjugated part to change the efficiency of the whole molecule and different side-chain to adjust the solubility and electrochemical abilities, which affect the injection and transport of carriors. The space structures of polymer molecule changed by the introduction of twist biphenyl structure. So the interactions among molecule also changed. We found out the change of aggregation behaviors of polyphenylene in solution and the exactly positions in molecular structures via new technologies of NMR spectra. And we hope this will give more help for application of materials and the condition optimizing of devices.