Synthesis and luminescence properties of novel phenyl-substituted poly(p-phenylene vinylene) derivatives

摘要

Three novel phenyl-substituted poly(p-phenylene vinylene) (PPV) derivatives, BDP-PPV, BDMP-PPV, and BDP-co-BDMP-PPV (1:1), have been successfully synthesized according to the Gilch route. The structures and properties of the monomers and the resulting polymers were characterized by using ~1H, ~(13)C NMR, elemental analysis, GPC, TGA, UV-vis absorption spectroscopy, photoluminescence (PL) and electroluminescence (EL) spectroscopy. The EL polymers possess excellent solubility in common solvents, good thermal stability with 5 percent weight loss temperature of more than 370 deg C, and higher photostability. The number-average molecular weight (M_n) and polydispersity index (PDI) of the polymers were in the range of (1.52-2.53) x 10~5 and 1.22-1.36, respectively. Double-layer light-emitting diodes (LEDs) with the configuration of ITO/polymer/Alq_3/Al devices revealed that the copolymer, BDP-co-BDMP-PPV (1:1), possessed the highest luminescence properties, which exhibited maximum luminance of up to 3850cdr at 23.5 V, and maximum luminescence efficiency of up to 2.68 cd/A.