How is silicone synthesized

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The silicones are systematically referred to as polyorganosiloxanes. They occupy an intermediate position between the inorganic silicates and the organic polymers. They were named "Silicones" when they were discovered: The British chemist Frederick Stanley Kipping intended to produce silicon-based ketones with the empirical formula R.2Synthesize SiO. In contrast to the C-O double bond, however, an Si-O double bond is not stable. Kipping received viscous oils whose dimethylsilyl units were linked via Si-O-Si bonds (siloxane bonds).

This structure corresponds to a linear, chain-like molecular structure. If a silicon atom is bound to three or four oxygen atoms, branching occurs there. The siloxane units are accordingly referred to as mono-, di-, tri- or tetrafunctional. Short notations have become commonplace for this:

There are the following possibilities of the molecular structure:

Linear polysiloxanes
These correspond to the construction type [MDnM] and occur as oils.
Cyclic polysiloxanes
As [Dn] to be discribed. The cyclosiloxanes [D3] (Hexamethylcycotrisiloxane), [D.4] (Octamethylcyclotetrasiloxane) and [D5] (Decamethylcyclopentasiloxane). They are used, for example, as starting materials for basic or acid-catalyzed ring-opening polymerization.
Branched Polysiloxanes
Tri- or tetrafunctional siloxane units serve as branching points. Your construction type is [MnD.mTOQp].
Cross-linked polysiloxanes
Chain or ring-shaped molecules are linked by a considerable number of T and Q units to form two- or three-dimensional networks.