(722ah) Synthesis of Polypyrrole/azocalixArene Salts: Electrical Properties and Thermal Stability
The inclusion of cage molecules into electroconducting polymers, ECPs, has opened new perspectives of application for the construction of ionic sensors. It is noted that sulphonated calixarenes can be immobilized in conducting polymers like PPy as dopants during electropolymerization. The grafting of calixarene to polythiophene has already been reported. Host-guest chemistry has also been used to facilitate the preparation of conducting polymers in aqueous solution using nonpolar monomers.
In present work we reported the synthesis of polypyrrole in the presence of water-soluble azocalixarene which obtained from diazo coupling reaction between calixarene and diazonium salts. Azo groups bring to calixarenes a chromogenic activity.The (5,11,17,23-tetrakis[(p-carboxyphenyl)azo]25,26,27,28 tetra hydroxy calixarene) was used as dopant anion. The effect of the content of azocalixarene onto properties of polypyrrole was investigated. Polypyrrole/azocalixarene salts were characterized by FTIR, TGA, SEM and conductivity measurements. The conductivity of polypyrrole increased in the presence of azocalixarene. TGA results indicated that the polypyrrole/azocalixarene salts have higher thermal stability than PPy. It was observed from SEM analysis that the particle diameter of PPy decreased with increasing content of azocalixarene.