Synthesis, characterization, thermal and dielectric properties of chalcone substituted polyphosphazenes

In this thesis study, firstly, substituted 4'-hydroxychalcone compounds (1a-1m) were synthesized from the reaction of substituted benzaldehydes (benzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 4-methoxybenzaldehyde, 3-methylbenzaldehyde and 4-methylbenzaldehyde) with 4'-hydroxyacetophenone. In the second step, 2,2,4,4-tetrachloro-6,6-bis[spiro(2',2"-dioxy-1',1"-biphenlyl)] cyclotriphosphazene (3) was obtained by the interaction of hexachlorotriphosphazene (2) with 2-2'-biphenol. In the third stage, poly[{3,3,5,5-tetrachloro-1,1-bis{spiro(2',2"-dioxy-1',1"-biphenylyl)}phosphazene] (4) containing biphenol was obtained by thermal polymerization of compound 3 in the presence of calcium sulfate dihydrate(CaSO4.2H2O) and amido sulfuric acide (H2NSO3H) in 1,2,4-trichlorobenzen at 220 OC. In the next step, novel phosphazene polymers bearing chalcone (4a-m) were synthesized by the interaction of polymer 4 with hydroxychalcone compounds (1a-m) in the presence of K2CO3 at the boiling temperature of THF. The synthesized compounds were purified by the suitable purification techniques (extraction, filtering, solving and precipitation). The structure of chalcone compounds (1a-m) were defined by FT-IR, 1H, 13C-NMR techniques. The structure of polyphosphazene compounds (4a-m) were characterized by elementel analysis, Jel Permation Chromatography (GPC), FT-IR, 31P, 1H, 13C, 13C-APT NMR techniques. Thermal behaviour of polymers were investigated by DSC and TGA analysis. Dielectric measurements of poly[{3,3,5,5-tetra(4-oxy-substituted-chalcone)-1,1-bis{spiro(2',2"-dioxy-1',1"-biphenylyl)}phosphazene] polymers (4a-m) were carried out by means of an impedance analyzer as a function of frequency.