In situ Polymerisation of Pyrrole Within the Lattices of Mesoporous Hexagonal Silica Systems

摘要

This study concerns the preparation and characterisation of electrically conducting polypyrrole-silica (PPy-Si) composites. Pyrrole monomers were adsorbed in nanoporous MCM-41 silicas exhibiting a hexagonal (H1) geometry, some of which had been functionalised using aminopropyltriethoxysilane (APS), and chlorotrimethylsilane (TMS). Composites were then produced through oxidative polymerisation and doping with anions, mainly sodium sulphonates (methylbenzenesulphate (MBSA), dodecylbenzenesulphonate (DBSA) and diethylhexylsulphosuccinate (DEHS)). An attempt to produce similar composites via direct threading of "soluble" polypyrrole was also investigated in order to study the effect of confined geometries on the growth and properties of polypyrrole chains. The final composites exhibited semiconducting properties (sigma up to 10(-3)S. cm-'), and improved thermal and environmental stabilities, making them suitable for applications such as sensors and antistatic agents.