Structures and Properties of Ormosils

Organically modified silicates (ORMOSILS) can be conveniently divided into three types. In Type A, the organic such as a dye, is mixed into the sol-gel liquid solution. On gelation, the organic is trapped in the gel. In Type B, a porous oxide gel is first formed and the porosity and pore size controlled by heating. An organic is then impregnated into the pores of the gel. In Type C, the organic is added to the oxide gel liquid solution but unlike Type A, a chemical bond is formed between the oxide and the organic. Types A, B and C can further be mixed. Together, these various types of ORMOSILS offer a very wide spectrum of chemistry, structures and applications. They constitute a new family of exciting materials with new scientific challenges and technical possibilities. A critical review will be presented on these ORMOSILS including structures, properties and applications.