Silicones are also called polysiloxanes. They are polymers of synthetic silcoxane. The silicones have a backbone made of alternating silicone and oxygen atoms,like (....si-o-si-o-si-o.....), the alkyl group is attached to si atom and the general expression is (R2sio) , where R is the organic group. So the si atom is attached to oxygen and organic group to fill its 4 valancies. Silicone are heat resiatant and rubber like.
Applications include use in sealents, adhesives lubricants, medicine, cooking utensils and for thermal and eletrical insulation.