Synthesis and electroluminescence properties of white‐light single polyfluorenes with high‐molecular weight by click reaction

Abstract

We reported a new way to synthesize single-chain white light-emitting polyfluorene (WPF) with an increased molecular weight using azide-alkyne click reaction. Four basic polymers with specific end-capping, which exhibited high-glass transition temperatures (T g > 100 C) and excellent thermal stability, were used as foundations of the WPF's synthesis; a bluelight polymer (PFB2) end-capped with azide groups can easily react with acetylene end-capped polymers (PFB1, PFG1, and PFR1, which are emitting blue-, green-and red-light, respectively) to form triazole-ring linkages in polar solvents such as N,N-dimethylforamide/toluene co-solvent at moderate temperature of 100 C, even without metal-catalyst. Several WPFs that consist of these four basic polymers in certain ratios were derived, and the polymer light-emitting diode device based on the high-molecular weight WPF was achieved and demonstrated a maximum brightness of 7551 cd/m 2 (at 12.5 V) and a maximum yield of 5.5 cd/A with Commission Internationale de l'Eclairage coordinates of (0.30, 0.33) using fine-tuned WPF5 as emitting material. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: [3355][3356][3357][3358][3359][3360][3361][3362][3363][3364][3365] 2011

Synthesis and Covalent Grafting of Tripod‐Shaped Oligo(p‐phenylene)s End‐Capped with Azide Groups

“…HCl, NaNO 2 ,a nd NaN 3 ,a sd escribed in the literature (Scheme3). [18] This is ao ne-pot reaction where HCl deprotects the NH-Boc moiety to obtain the free amine groups, and this is followed by their conversion into azide groups by using NaNO 2 and thereafter NaN 3 .B oth tripods 2a and 2b were obtained in good yields of 50 and 65 %, respectively. Furthermore, in order to prepare giant tripod 1a,i nitially we carriedo ut the homologation of the biphenyl 8 by reaction with 7 (Scheme 4) followedb yt he coupling with the silicon core 4a.…”

Poly(2,6‐di(thiophene‐2‐yl)‐3,5bis(4‐(thiophene‐2‐yl)phenyl)dithieno [3,2‐b;2',3'‐d]thiophene)/carbon nanotube composite for capacitor applications

“…The 3,5‐bis(4‐bromophenyl)dithieno[3,2‐ b ;2',3'‐ d ]thiophene ( 2 ) and 4,4,5,5‐tetramethyl‐2‐(thiophen‐2‐yl)‐[1,3,2]‐dioxaborolane ( 4 ) were synthesized following the literature procedures.…”

Improving the performance of polymer light-emitting devices with chemical tools

“…Polyfluorene derivatives containing BT, triarylamine and 1,2,3‐triazole units in the main chain gave white‐emitting PLEDs with the structure ITO/PEDOT:PSS/poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐ co ‐(4,4′‐( N ‐(4‐s‐butylphenyl))diphenylamine)]/polymer/Cs/Al. A maximum brightness of 7551 cd m −2 with a maximum current efficiency of 6.2 cd A −1 were obtained . A star‐shaped polymer made up of 0.01% bis(indolylmaleimide) dye as the core and polyfluorene chains yielded a white‐emitting device with the structure ITO/PEDOT:PSS/polymer/TPBI/LiF/Al .…”