Synthesis, Photophysical Studies of Blue‐Light‐Emitting Alternating Polymers from Substituted 9‐Sila Fluorenes and Substituted p‐Phenylacene

Abstract

Five new alternating polymers were synthesized from 2,7‐dibromo‐3,6‐dimethoxy‐9‐sila fluorene with varied alkyl and aryl groups substituted at 9‐position and 2‐tert butyl‐9,10‐di (p hydroxyl phenyl) anthracene. The monomers and the polymers were synthesized in good yields at each stage of preparation and with high degree of reproducibility. The copolymers were soluble in common organic solvents like toluene, xylene, THF and chloroform. Chemical and optoelectronic characterizations of the polymers were done by 1H and 13C NMR, GPC, UV absorption, photoluminescence and cyclic voltammetric studies. Pure blue light emission, with the maximum absorption wavelength in the range of 445 to 457 nm and the PL quantum efficiency in the range of 0.55 to 0.91 were recorded for the synthesized copolymers in their solution in CHCl3. The ITO/CuPc/α‐NPD/ copolymer/ Alq3/LiF/Al devices fabricated from the polymers gave pure blue light emission irrespective of the substitution on silicon atom of the silafluorene moiety. The properties both photophysical and electrochemical, of the synthesized alternating polymers are quite suitable for the development of blue light emitting devices.

Ullmann coupling for low-cost synthesis of anthracene-based polyfluorenes: A photophysical approach

“…4,4′-(2,7-Dibromo-9H-fluorene-9,9-diyl) dianiline) ( I ) (FDA) was synthesized using a procedure reported. 46 –48,50 The general reaction scheme is shown in Figure 1.…”

“…51 –55 Figure 2 and Figure S1 show the reaction scheme and the experimental procedure for the synthesis of the acene monomers (II) . 46 –48…”

“…The yield of the resulting brown colored polymer was around 65–70%. 46 –48 Using a similar scheme, series of the FDA-diphenylacene polymers P1, P2, and P3 were synthesized.…”

“…23,24 We also emphasize the low-cost copper-catalyzed synthesis of polymers with relatively high molecular weight and strong thermal and optical properties. 46 –48…”

Alkyl and allyl substituted polydibenzofluorene: blue emitters for future display applications

“…Polymer occurs in both amorphous and crystalline form. The polymer's crystallite size is used to define the polymer character and degree of crystallinity present in the polymer sample [31][32][33]42]. The polymers' crystallite sizes were determined using the Deby-Scherrer relationship and found within 0.2251-3.6155 range as shown in Table S 1 (supporting information).…”