A Hyperbranched Copolymer of Poly(dialkoxy-p-phenylenevinylene) and Trivinylenephenylene Units: Synthesis, Characterization, Photo- and Electroluminescence Properties

Abstract

A novel hyperbranched copolymer, poly(2,4,6-tributyloxy-1,3,5-trivinylenephenylene-co-2methoxy-5-octyloxy-p-phenyelenevinylene) PTBOTV-co-PMOPV, and a linear counterpart poly(2-methoxy-5octyloxy-p-phenyelenevinylene) (PMOPV) were synthesized by the Gilch polymerization and characterized with UV-vis, FT-IR, 1 H NMR and Photoluminescence (PL) spectroscopy. PTBOTV-co-PMOPV showed excellent solubility, good film-formation ability, and high thermal stability. The UV-vis, PL, and electroluminescence (EL) spectra of PTBOTV-co-PMOPV were blue-shifted approximately 9-15 nm on comparison with those of PMOPV. The polymer light-emitting diode (PLED) was fabricated in ITO/PEDOT (50 nm)/polymer (60 nm)/ Alq 3 (30 nm)/LiF (1 nm)/Al (200 nm) configuration. The PTBOTV-co-PMOPV exhibited the maximum external quantum efficiency (EQE) of 0.26% at 60.7 cd/m 2 , while the PMOPV device showed the maximum EQE of 0.17% at 88 cd/m 2 .

Functional hyperbranched polymers with advanced optical, electrical and magnetic properties

“…Besides hyperbranched PFs, there were many other HBPs prepared as light-emitting materials, e.g. hyperbranched PPV, [93][94][95] hyperbranched polytriphenylamine, 96 etc. and their derivatives.…”

Poly(phenylenevinylenes)

“…An LED device using 12 (TEH-PPV) gives green electrolumescence at 505 and 542 nm. Interestingly, reaction of 1,4-bis(chloromethyl)-2-methoxy-5-octyloxybenzene with 1,3,5-trichloromethyl-2,4,6-tributoxybenzene gives a soluble hyperbranched copolymer 14 (entry 5) [30]. Some additional examples with aryl [31,32], porphrin [33], and bulky tricyclodecane (TCD) [34] substitution can be found in literatures.…”

Multifunctional Hyperbranched Oligo(fluorene vinylene) Containing Pendant Crown Ether: Synthesis, Chemosensory, and Electroluminescent Properties

“…However, it is well-known that hyperbranched polymers exhibit better film-forming ability, improved film morphology, and reduced crystallization, which have been ascribed to their three-dimensional structures. 22,23 To conclude, hyper-branched HOFC reveals thermal stability and homogeneous morphology superior to LOFC after thermal cross-linking. These characteristics are key factors in obtaining highperformance electroluminescent devices.…”

“…Stable amorphous film is readily obtainable from the hyperbranched polymers owing to reduced interchain cohesive force, when compared with analogous linear counterparts. The amorphous and homogeneous morphology in the emitting layer is critical in PLED device fabrication because it contributes beneficially to performance enhancement. − In addition, hyperbranched polymers, prepared by Heck coupling or Witting reaction, may possess many reactive functional groups through controlling stoichiometry of the feed monomers; for instance, styryl-functionalized oligomers have a lot of reactive vinyl end-groups, which are promising candidates of thermal cross-linkable precursor. − Hyperbranched oligomers own more terminal vinyl groups than linear counterparts, leading to higher cross-linking density after heat treatment. The thermally cured polymers should possess better solvent resistance and thermal stability that are highly required in fabricating PLED devices.…”

“…The amorphous and homogeneous morphology in the emitting layer is critical in PLED device fabrication because it contributes beneficially to performance enhancement. [21][22][23][24] In addition, hyperbranched polymers, prepared by Heck coupling or Witting reaction, may possess many reactive functional groups through controlling stoichiometry of the feed monomers; for instance, styryl-functionalized oligomers have a lot of reactive vinyl endgroups, which are promising candidates of thermal cross-linkable precursor. [25][26][27] Hyperbranched oligomers own more terminal vinyl groups than linear counterparts, leading to higher crosslinking density after heat treatment.…”