Ankara : The Department of Chemistry and the Institute of Engineering and Sciences of Bilkent University, 2007.Thesis (Master's) -- Bilkent University, 2007.Includes bibliographical references leaves 90-94.In this thesis, a series of polyfluorene based copolymers have been prepared via
Suzuki Coupling for use in light emitting diodes (LEDs). Polyfluorene based
polymers are synthesized from different monomers. These polymers are
characterized with spectroscopic techniques including FT-IR, UV-VIS, Fluorescence
and 1H, 13C NMR.
Conjugated polymers are attractive chemical structures inherently allowing charge
transport. However, in the solid state, conjugated polymers lack stability and form
aggregates. To overcome this problem, conjugated polymers can be converted to
insulated molecular wires. This can be achieved by separation of the conjugated
polymer chains by a macrocycle.
In this study, encapsulation of conjugated polymers is tried with two methods. First
method is to encapsulate the polymer main chain by macrocycles. Polypyrrole based
polypseudorotaxane is prepared in this way. Pyrrole is complexed with the
cucurbit[6]uril (CB(6)) and following chemical oxidation by FeCl3 in acidic medium
yields the desired polypseudorotaxane. Spectroscopic investigations such as FT-IR,
UV-VIS, Fluorescence and 1H-NMR confirm the formation of polypyrrole based
polypseudorotaxane. The second method involves the rotaxanation of the polymer side chains. For this
purpose, fluorene based monomers are chosen because the 9th position of fluorene
can be easily functionalized. After attaching suitable groups to the 9th position of
fluorene, the rotaxane formation was attempted via 1,3 dipolar cycloaddition in the
presence of CB(6).
A white light emitting diode is prepared using a hybrid inorganic and organic
material based system. Prepared conjugated polymers were used in white light
generation. Good results are obtained with high CRI indices. Also the thermal
stability of the conjugated polymers is studied by FT-IR, UV-VIS and Fluorescence
spectroscopic techniques under heat exposure.Koldemir, ÜnsalM.S
