Why should the monomer used in addition polymerisation through free radical pathway be very pure?

Explanation

### Step-by-Step Solution:

1. **Understanding Addition Polymerization**:
- Addition polymerization is a process where monomers join together to form a polymer. This process can occur through various pathways, one of which is the free radical pathway.

2. **Role of Monomers**:
- Monomers are the building blocks of polymers. The quality and purity of these monomers significantly affect the properties of the resulting polymer.

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