Effects of molecular weight on polyfluorene-based polymeric light emitting diodes

We synthesized polyfluorene-based polymers as a blue emitting material of polymeric light-emitting diodes (PLEDs). PLEDs using high-molecular-weight component are found to have high luminance and efficiency for high fluorescence quantum yield of materials. We prepared devices using poly(9,9-dioctylfluorene) (PDOF) with different molecular-weight distributions. Electroluminescence characteristics of devices using the PDOF with the high-molecular-weight component were superior to those of the devices using PDOF with the low-molecular-weight component.