Question

Silicon has a strong tendency to form polymers like silicones. The chain length of silicone polymer can be controlled by adding

• A. $MeSiC{l}_3$
  
• B. $M{e}_{3}SiCl$
  
• C. $M{e}_{4}Si$
  
• D. $M{e}_{2}SiC{l}_2$
  

Answer 1

The correct option is B $M{e}_{3}SiCl$


Organo silicone polymers have $(-Si{R}_{2}O-)$ as a repeating unit.
i.e.,

This polymer of silicon is called Silicones.

$(C{H}_3{)}_{2}SiC{l}_2$ on hydrolysis forms

$\left(C{H}_3{)}_{2}Si\right(OH{)}_2$ which polymerises to form


On adding $(C{H}_3{)}_{3}SiCl$ it forms $(C{H}_3{)}_{3}SiOH$

The chain length of the polymer can be controlled by adding $(C{H}_3{)}_{3}SiCl$ which blocks the ends as shown below: