Silicones : It's Pharmaceutical Applications

Silicones (more accurately called polymerized siloxanes or polysiloxanes) are mixed inorganic-organic polymers with the chemical formula [R2SiO]n, where R is organic groups such as methyl, ethyl, and phenyl. These materials consist of an inorganic silicon-oxygen backbone (-Si–O–Si–O–Si–O-) with organic side groups attached to the silicon atoms, which are four-coordinates. However in many instances silicone (a polymer) was also confused with silicon (a metal) or silica (an inorganic compound). Although silicones contain silicon atoms, they are not made up exclusively of silicon, and have completely different physical characteristics from elemental silicon. A true silicone group with a double bond between oxygen and silicon does not exist in nature; chemists find that the silicon atom forms a single bond with each of two oxygen atoms, rather than a double bond to a single atom.(1)