Neet Solved Paper 2013 Question 30

Question: Which of these is not a monomer for a high molecular mass silicone polymer?

Options:

A) $ MeSiC{l_3} $

B) $ M{e_2}SiC{l_2} $

C) $ M{e_3}SiCl $

D) $ PhSiC{l_3} $

Show Answer

Answer:

Correct Answer: C

Solution:

  • $ Me _3SiCl $ is not a monomer for a high molecular mass silicone polymer because it generates Me3SiOH when subjected to hydrolysis which contains only one reacting site. Hence, the polymerisation reaction stops just after first step. $ \text{Me-}\underset{\begin{smallmatrix} | \\ Me \end{smallmatrix}}{\overset{\begin{smallmatrix} Me \\ | \end{smallmatrix}}{\mathop{Si}}},\text{-OH+HO-}\underset{\begin{smallmatrix} | \\ Me \end{smallmatrix}}{\overset{\begin{smallmatrix} Me \\ | \end{smallmatrix}}{\mathop{Si}}},\text{-Me}\xrightarrow[\text{-}{H_2}O]{{}} $ $ \underset{Final,product,\text{(dimer)}}{\mathop{\text{Me-}\underset{\begin{smallmatrix} | \\ Me \end{smallmatrix}}{\overset{\begin{smallmatrix} Me \\ | \end{smallmatrix}}{\mathop{Si}}},\text{-O-}\underset{\begin{smallmatrix} | \\ Me \end{smallmatrix}}{\overset{\begin{smallmatrix} Me \\ | \end{smallmatrix}}{\mathop{Si}}},\text{-Me}}}, $