Question
Explain the preparation of silicones.
✓
Answer
Generally silicones are prepared by the hydrolysis of dialkyldichiorosilanes $\left( R _2 SiCl _2\right)$ or diaryldichlorosilanes $Ar _2 SiCl _2$, which are prepared by passing vapours of RCl or ArCl over siliconat 570 K with copper as a catalyst.
$2 RCl+\underset{\longrightarrow}{Si C u / 570 k R_2 SiCl_2}$
The hydrolysis of dialkvlchloro silanes $R _2 SiCl _2$ yields to a straight chain polymer which grown from both the sides
The hydrolysis of monoalkylchloro silanes $RSiCl_3$, yields to a very complex cross linked polymer Linear silicones can be converted into cyclic or ring silicones when water molecules is removed
$2 RCl+\underset{\longrightarrow}{Si C u / 570 k R_2 SiCl_2}$
The hydrolysis of dialkvlchloro silanes $R _2 SiCl _2$ yields to a straight chain polymer which grown from both the sides
The hydrolysis of monoalkylchloro silanes $RSiCl_3$, yields to a very complex cross linked polymer Linear silicones can be converted into cyclic or ring silicones when water molecules is removed
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