Synthesis, structure analysis, investigation of conductivity, thermal properties of polyphenol derivatives containing a rhodanine moiety and their Cu(II), VO(IV) complexes

Abstract

In this study, 5-benzylidenerhodanine derivatives namely 5-(2-hydroxybenzylidene)-2-thioxothiazolidin-4-one (SAR) and 5((2-hydroxynaphthalen-1-yl)methylene)-2-thioxothiazolidin-4-one (HNAR) used as monomer. The new polymers of SAR and HNAR (PSAR and PHNAR respectively) were synthesized by oxidative polycondensation reaction. The polymers were characterized by elemental, FT-IR, UV-Vis, H-1 NMR,C- 13 NMR, TG-DTA analyses techniques. The molecular weight distribution values of the PSAR and PHNAR were determined by size exclusion chromatography (SEC) analysis. According to the SEC analyses, the number average molecular weight (M-n), weight average molecular weight (M-w) and polydispersity index (PDI) values of PSAR and PHNAR were found to be 5300, 7250 g mol(-1) and 1.368; 5750, 7350 g mol(-1) and 1.278, respectively. The Cu (II), VO (IV) complexes of PSAR and PHNAR (PSAR-Cu and PSAR-VO) were successfully prepared using Cu (AcO)(2)xH(2)O and VOSO(4)x5H(2)O hydrate salts. The polymer-metal-complexes were characterized by FT-IR, elemental and TG-DTA analysis techniques. The weight losses of PHNAR, PHNAR-Cu, PHNAR-VO, PSAR, PSAR-Cu and PSAR-VO were found to be 69.50, 58.50, 62.25, 89.05, 74.55 and 61.75% at 1000 degrees C, respectively. TG analyses were showed to be stable of synthesized polymers against thermal decomposition. Electrical properties of doped polymers, undoped polymers and their complexes were determined. Also, the optical band gaps (Eg) of these complexes were calculated from their absorption edges.