Explain the preparation of silicones.

Explanation

Generally silicones are prepared by the hydrolysis of dialkyldichlorosilanes `(R_(2)SiCl_(2))` or diaryldicholorosilanes `Ar_(2)SiCl_(2)`, which are prepared pasing vapours of RCl or ArCl oversiliconat 570 K with copper as a catalyst.
`2RCl+Sioverset(Cu//570K)(to) R_(2)SiCl_(2)`
The hydrolysis of dialkylchloro silanes `R_(2)SiCl_(2)` yields to a straight chain polymer whcih grown from bot the sides

The hydrolysis of monoalkylchloro silanes `RSiCl_(3)` yiels to a very complex cros linked polymer. Linear silicones can be converted into cyclic or ring silicones when water molecules is removed from the terminal -OH groups.