Study of the optical properties of poly(vinyl chloride)-4-[(5-mercapto-1,3,4-thiadiazol-2-yl)diazenyl]phenol complexes

Abstract

The most widely practiced reaction of diazonium salts is azo coupling. In this process, the diazonium compound is attacked by an electron-rich substrate. When the coupling partners are arenes (phenols), the process is an example of electrophilic aromatic substitution. Poly (vinyl chloride) (PVC) react with 4-[(5-mercapto-1,3,4-thiadiazol-2-yl)diazenyl]phenol (L) in THF to form the PVC-L compound, which have been characterized by spectroscopic methods. PVC-L has further been reacted with different metals ions to form PVC-L-M^II complexes. The structure of these complexes has been characterized by FT-IR and UV-Vis spectrophotometry. The optical properties in the region from 200-900 nm were also studied using UV-Vis spectrophotometer. The optical data analyzed and interpreted in term of the theory of phonon assisted direct electronic transitions according to energy gap data the conductivity of PVC and the complexes.