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Polyfluorene Derivatives (polyfluorene + derivative)
Selected AbstractsA Click Approach to Chiral-Dendronized Polyfluorene DerivativesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 23 2007Zi-Tong Liu Abstract A new kind of chiral-dendronized binaphthyl-containing polyfluorene derivatives has been synthesized through "click chemistry" efficiently. The resulting copolymers exhibited desirable properties, such as excellent solubility, good thermal stability, and considerably high molecular weights. The photophysical properties of the copolymers were investigated in details, and the results indicated that the combination of chiral binaphthyl unit and bulky dendron could effectively suppress intermolecular packing and aggregation. In addition, the investigation of circular dichroism behavior of these chiral-dendronized copolymers showed a strong Cotton effect at long wavelength (373,379 nm), indicating that the chirality of the binaphthyl units was transferred to the whole polyfluorene backbone. [source] White Electroluminescence by Supramolecular Control of Energy Transfer in Blends of Organic-Soluble Encapsulated PolyfluorenesADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Sergio Brovelli Abstract Here, it is demonstrated that energy transfer in a blend of semiconducting polymers can be strongly reduced by non-covalent encapsulation of one constituent, ensured by threading of the conjugated strands into functionalized cyclodextrins. Such macrocycles control the minimum intermolecular distance of chromophores with similar alignment, at the nanoscale, and therefore the relevant energy transfer rates, thus enabling fabrication of white-light-emitting diodes (CIE coordinates: x,=,0.282, y,=,0.336). In particular, white electroluminescence in a binary blend of a blue-emitting, organic-soluble rotaxane based on a polyfluorene derivative and the green-emitting poly(9,9-dioctylfluorene-alt-benzothiadiazole (F8BT) is achieved. Morphological and structural analyses by atomic force microscopy, fluorescence mapping, µ-Raman, and fluorescence lifetime microscopy are used to complement optical and electroluminescence characterization, and to enable a deeper insight into the properties of the novel blend. [source] Polyfluorenes: Twenty years of progressJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2001Mario Leclerc Abstract Polyfluorenes are an important class of electroactive and photoactive materials. In the last three years this research field has literally exploded because of polyfluorenes' exceptional electrooptical properties for applications in light-emitting diodes. This is the only family of conjugated polymers that emit colors spanning the entire visible range with high efficiency and low operating voltage. Other unusual optical and electrical properties are made possible with polyfluorene derivatives, such as thermochromism and conducting base-doped polyelectrolytes. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2867,2873, 2001 [source] A Click Approach to Chiral-Dendronized Polyfluorene DerivativesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 23 2007Zi-Tong Liu Abstract A new kind of chiral-dendronized binaphthyl-containing polyfluorene derivatives has been synthesized through "click chemistry" efficiently. The resulting copolymers exhibited desirable properties, such as excellent solubility, good thermal stability, and considerably high molecular weights. The photophysical properties of the copolymers were investigated in details, and the results indicated that the combination of chiral binaphthyl unit and bulky dendron could effectively suppress intermolecular packing and aggregation. In addition, the investigation of circular dichroism behavior of these chiral-dendronized copolymers showed a strong Cotton effect at long wavelength (373,379 nm), indicating that the chirality of the binaphthyl units was transferred to the whole polyfluorene backbone. [source] | ||||||||||