Studies On Preparation Of Polyaniline/Inorganic Nano-oxides Organic-inorganic Hybrid Materials

Research in hybrid materials has experienced considerable growth in recent years with increasing interest from a wide range of industries. Hybrid materials have been on behalf of a way to design new materials. Polymer-based organic-inorganic hybrid materials has been widely used in many areas because of its superior properties. In particularly, hybrid materials of polyaniline and inorganic particles have attracted more and more attention. Recently, polyaniline coated inorganic particles has been extensively studied because they frequently exhibit unexpected hybrid properties.In this thesis, our main aim is to circumfused with the preparation and property of polyaniline-inorganic particles hybrid materials. The research is focused in three aspects:1. The hybrid materials of polyaniline and TiO2 was prepared by in situ chemical oxidative grafting polymerization. The aniline as initiator site convalent attachment on the surface of TiO2 were obtained utilizing the very cheap toluene diisocyanate as a surface modifying coupling agent. Results from the characterizations of SEM,TG and electrical conductively indicate that grafting PANI from onto the surface of nano TiO2 is successfully achieved. The hybrid materials obtained in this study has a semiconductive property.2. Amino-functionally modified SiO2 particles were prepared by sol-gel process on the basis of Stober method. The coating of polyaniline onto SiO2 particles was carried out via in situ chemical oxidative covalently graft polymerization from the amino-functionally modified SiO2 particles. Results from the characterizations of FIRT,TG,Zeta potentials and electrical conductively indicate that grafting PANI from onto the surface of SiO2 particles is successfully achieved. The Zeta potentials of the hybrid particles showed a positive indicating that a sufficient number of negatively charged sites on the silica surfaces were neutralized by the PANI.3. A effective and reproducible method for the preparation of core-shell PANI@SiO2 hybrid nanoparticles was developed successfully. Vinyl-functionally modified SiO2 particles were prepared by sol-gel process on the basis of Stober method. Carboxylic-functionally modified SiO2 particles were obtained via oxidation of vinyl groups to carboxylic groups. The aniline monomers electrostatically assembly to the silica surface were then polymerized by ammonium persulfate as an oxidizing agent. Results from the characterizations of FIRT,TG,Zeta potentials and particle size distributions indicate that preparation of core-shell PANI@SiO2 organic-inorganic hybrid nanoparticles is successfully achieved. The core-shell PANI@SiO2 organic-inorganic hybrid nanoparticles obtained in this study can been used as pH sensors.