Silicone resins are made by:

Options

A. dissolving a mixture of `PhSiCl_(3)` and `(Ph)_(2)SiCl_(2)` in toluene and then hydrolysis with water.
B. hydolysing a mixture of `(CH_(3))_(2)SiCl_(2)` and `(CH_(3))_(3)SiCl`
C. hydrolysis of `(CH_(3))_(2)SiCl_(2)`
D. none

Answer

A

Explanation

(A)When a mixture of `PhSiCl_(3)` and `(Ph)_(2)SiCl_(2)` is dissolved in toluene and then hydrolysed with water silicon resins are obtained.
(B)Silicones from the hydrolysis of a mixture of `(CH_(3))_(3)SiCl` & `(CH_(3))_(2)SiCl_(2)`
The dichloro derivative will form a long chain polymer as usual.But the growth of this polymer can be blocked at any stage by the hydrolysis product of mono-chloro derivative.
`OH-underset(R)underset(|)overset(R)overset(|)(Si)-OH+OH-underset(R)underset(|)overset(R)overset(|)(Si)-OHunderset(-H_(2)O)toOH-underset(R)underset(|)overset(R)overset(|)(Si)-O-underset(R)underset(|)overset(R)overset(|)(Si)-OH`
In this manner several molecules may combine to form a long chain polymer whose both the ends will be occupied by `-OH` groups.Such compounds are generally represented from the following formula.
`OH-underset(R)underset(|)overset(R)overset(|)(Si)-O-underset(R)underset(|)overset(R)overset(|)(Si)-O-underset(R)underset(|)overset(R)overset(|)(Si)-O-`