Wu, Yuling published the artcileSynthesis and properties of hyperbranched polymers for polymer light emitting devices with sunlight-style white emission, Quality Control of 100-70-9, the main research area is fluorene carbazole iridium phosphor hyperbranched polymer light emitting device; Suzuki coupling polycondensation white light emission electroluminescent device.
A new series of hyperbranched polymers consisting of fluorene-alt-carbazole as the branches and the 3D-structured spiro[3.3]heptane-2,6-dispirofluorene (SDF) as the core were designed and synthesized by one-pot Suzuki coupling polycondensation. A phosphor group with broad full width at half maximum (FWHM) bis(1-phenyl-isoquinoline)(acetylacetonato)iridium(III)(Ir(Brpiq)2acac, 0.08 mol%) as the red-light emitting unit and bis(2-(4-bromophenyl)-1-[6-(9-carbazolyl)hexyl]-imidazole)(2-(5-(4-fluorinated phenyl)-1,3,4-triazole)pyridine)iridium(III)((CzhBrPI)2Ir(fpptz)) as the green-light emitting unit were introduced into the backbones to obtain sunlight-style white-light emission by adjusting the feeding ratios of (CzhBrPI)2Ir(fpptz) (0.08 to 0.32 mol%). The results indicate the LUMO levels of polymers were reduced and the electron injection was improved because of excellent electron-transporting ability of the triazole unit in the green group. The hyperbranched structures can effectively suppress the polymers’ chain distortion and aggregation, and promote the incomplete Forster resonance energy transfer efficiency from fluorene-alt-carbazole segments to Ir complex units. As a result, the devices with hyperbranched polymer light-emitting layers realize white light emission, and the optimized device also exhibits good electroluminescent (EL) performance with CIE coordinates at (0.32, 0.31), a maximum luminance of 9054 cd m-2, a maximum current efficiency of 3.59 cd A-1 and a maximum CRI of 91.
RSC Advances published new progress about Current density. 100-70-9 belongs to class nitriles-buliding-blocks, name is Picolinonitrile, and the molecular formula is C6H4N2, Quality Control of 100-70-9.
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts