Question

Draw the mechanism for the radical polymerization of vinyl acetate $({\mathrm{CH}}_2={\mathrm{CHOCOCH}}_3)$ using${\left({\mathrm{CH}}_3\right)}_{\mathbf{3}}\mathbf{CO}\mathbf{-}\mathbf{OC}{\left({\mathrm{CH}}_3\right)}_{\mathbf{3}}$ as the initiator.

Short answer

Answer

The mechanism for radical polymerization of vinyl acetate using the given initiator is:

• Initiation

• Propagation

• Termination

Step-by-step solution

Radical polymerization

The polymerization technique where free radicals serve as building blocks and get added up to form a polymer by involving various mechanisms, it is known as radical polymerization.

Radical polymerization contains three major steps. They are:

• Initiation,
• Propagation, and
• Termination.

Initiation 

The electrons present in the oxygen atoms of ${\left({\mathrm{CH}}_3\right)}_3\mathrm{CO}-\mathrm{OC}{\left({\mathrm{CH}}_3\right)}_3$will split and result in the formation of free radicals. The generated free radical molecule combines with ${\mathrm{CH}}_2={\mathrm{CHOCOCH}}_3$. The mechanism is shown below.

Initiation process

Propagation

The molecule obtained in the initiation combines with ${\mathrm{CH}}_2={\mathrm{CHOCOCH}}_3$. Propagation repeats several times. Its mechanism is shown below.

Propagation process

Termination

The molecule obtained during propagation combines repeatedly.

Termination mechanism is shown below.

Termination process.