A polymer that contains silicone, carbon and oxygen. Silicone resins were first discovered by F. Kipping in England in 1900, but were not commercially produced until 1943 by Dow Corning. Silicone resins are made by the room-temperature vulcanisation (RTV) of silicone oils. They can cure either with moisture in the air (single-component system) or by the addition of a peroxide catalyst (two-component system). Once cured, silicone resins are chemically inert and can exist as elastomers and resins (both thermosetting and thermoplastic). They function over a wide temperature range, are water repellent and have very poor adhesion. Silicones are used as sealants, moulding compounds and varnishes. Synonyms: polysiloxane; organosiloxane; SI; Silastic Museum of Fine Arts, Boston (2000). [J. Cassar, R. de Angelis]