Synthesis and photophysical studies of conjugated polycarbonyls containing carbazole and triphenylamine units

Abstract

Semiconducting Polymers are widely used in optoelectronic applications, such as Organic newlinelight emitting Diode(OLED), Organic field effect transistors(OFT), Organic solar cells(OSC) so newlineon. Most of Conjugated poly carbonyls are act as semiconducting materials, which is already used newlinein active layer for polymer light emitting diodes. Most of the semiconducting materials are made newlineby C-C coupling methods. These methods are highly expensive and hazardous our environment. newlineThis thesis is mainly on the design and synthesis of conjugated poly carbonyls by simple method newlinewith cost effective from A2 and B2 type monomer via Claisen-Schmidt condensation route. newlineSynthesis Solution-processable poly(dibenzalacetone) and poly(dibenzalcyclohexanone) by the newlinecondensation of 1,4-dialkoxy-bisbenzaldehyde and acetone/cyclohexanone using classic Claisen newlineSchmidt condensation. The availability of and#945;,and#946;-unsaturated ketone on the backbone is readily newlineconverted into hydrazine hydrate to obtain poly(pyrazoline acetate), a nonconjugated polymer on newlinethe backbone, which shows enhanced emission characteristics. The highest occupied molecular newlineorbital lowest unoccupied molecular orbital (HOMO LUMO) of levels of poly(pyrazolines) has newlinea band gap of 1.54 eV as calculated from cyclic voltammetry and UV vis studies. newlineIV characterization of the film shows low turn-on voltage of 5.3 V. HOMO LUMO is calculated newlineby density functional theory. Alternating and random copolymers of carbazole and triphenylamine newlinecontaining polychalcones are prepared by adopting simple Claisen-Schmidt route via A2 + B2 newlineapproach. Terephthaldehyde derivative was used as an additional comonomer along with newlinebisaldehyde of triphenylamine to obtain a random copolymer. All prepared polymers are readily newlinesoluble in common organic solvents and the polymers exhibited narrow poly dispersity. The newlinepolymers are thermally stable and no observable degradation is observed until 350 ºC. This result newlinesuggests that these molecules have great potential toward polymer organic light-emitting diode