Synthesis and Electroluminescent Properties of Disubstituted Polyacetylene Derivatives Containing Multi-Fluorophenyl and Cyclohexylphenyl Side Groups

A new series of disubstituted polyacetylene derivatives that contain multi-fluorine atoms on the pendent phenyl ring have been synthesized and characterized. The results reveal a greater red-shift in UV-vis absorption and PL emission upon incorporating more fluorine atoms on the pendent phenyl ring. Among them, disubstituted polyacetylene with a difluorophenyl group (PDPA-2F) showed the highest luminescent efficiency. The F device performance can be promoted by blending a hole-transporting material TM-TPD into PDPA-2F as the active layer or by using a light-emitting copolymer in which PDPA-2F was copolymerized with a carbazole group (PDPA-2Fcab). A light-emitting diode of ITO/PEDOT/PDPA-2Fcab/Ca/Al revealed a maximum luminescence of 4230 cd . m(-2) at 14 V and a maximum current efficiency of 3.37 cd . A(-1) at 7 V.