title: Preparation and Characterization of poly(Azomethines) Containing Ether and Methylene Bridges: Photophysical, Electrochemical, Conductivity and Thermal Properties.
abstract: In this paper, a series of polyazomethines (PAZs) were prepared using dihydroxy substituted Schiff bases and 1,4-diiodobenzene. Also, different group effect such as methylene carbon and etheric oxygen bridges on photophysical, electrochemical, conductivity and thermal properties were clarified. The new polymeric materials structures were confirmed by means of1H-NMR, FT-IR and UV-vis measurements. The molecular weight distributions of polymers were determined with gel permeation chromatography (GPC) measurements. Photophysical behaviors of polymers were explored by UV-vis absorption and fluorescence measurements. TGA-DTA and DSC techniques have been used for the thermal characterization of the PAZs. Thermal data and fluorescence measurements showed that etheric oxygen bridge containing polymers have a bit higher char and emission intensity than the methylene carbon bridge carrying polymers. According to TG analysis, Tonvalues of P-2MPDP, P-2-OPDP, P-4-MPDP and P-4-OPDP were found as 210, 250, 249 and 233 °C, respectively. The HOMO-LUMO energy levels, electrochemical (E'g) and optical (Eg) band gaps were calculated from cyclic voltammetry (CV) and UV-vis measurements, respectively. The electrochemical (Eg') band gaps values of P-2MPDP, P-2-OPDP, P-4-MPDP and P-4-OPDP were calculated as 2.68, 2.32, 2.34 and 2.07, respectively. Additionally, four-point probe technique was used to measure solid state electrical conductivities of both doped and undoped states of the PAZs.
authors: Polymer Synthesis and Analysis Laboratory, Department of Chemistry, Çanakkale Onsekiz Mart University, 17020, Çanakkale, Turkey. kayaismet@hotmail.com.
authors: İsmet
authors: İ
authors: Kaya
authors: Polymer Synthesis and Analysis Laboratory, Department of Chemistry, Çanakkale Onsekiz Mart University, 17020, Çanakkale, Turkey.
authors: Tahsin
authors: T
authors: Yılmaz
keywords: Band gap; Cyclic voltammetry; Photophysical properties; Poly(azomethines); SEM; Thermal stability