Hybrid sols as intermediates to inorganic-organic nanocomposites

Abstract

For the preparation of inorganic-organic hybrid materials, synthesis processes have been developed to fabricate so-called hybrid sols, which contain an inorganic core (ceramic or glass) with nano-scale dimensions surface modified by organic groupings. These groupings have been reacted to the particle surface either by amino functional silanes (e.g. in case of iron oxide nanoparticles for amino group containing silanes) reacting with aliphatic acids to make surfaces ureactive and reduce the particle-to-particle interaction by acids, or silanes with polymerizable groupings reacted with organic monomers. In the paper a summary of the recent work and the development of structural models is given. Moreover, it could be shown that surface charges can be generated in the particles within already gelled systems and thus, particles can be tranported by electric fields toform gradient index materials.