Which is not an example of addition polymer?

Options

A. Neoprene
B. PMMA
C. PVC
D. Dacron

Answer

To determine which of the given options is not an example of an addition polymer, we need to understand what addition polymers are and how they are formed.

### Step-by-Step Solution:

1. **Understanding Addition Polymers**:
- Addition polymers are formed through a process called addition polymerization, where monomer units join together without the loss of any small molecules (like water or alcohol).

2. **Identifying Examples of Addition Polymers**:
- **Neoprene**: This is formed from the monomer isoprene through addition polymerization. Therefore, neoprene is an addition polymer.
- **Polymethyl Methacrylate (PMMA)**: This polymer is formed from the monomer methyl methacrylate (MMA) through addition polymerization. Hence, PMMA is also an addition polymer.
- **Polyvinyl Chloride (PVC)**: This polymer is produced from the monomer vinyl chloride through addition polymerization. Thus, PVC is an addition polymer as well.

3. **Identifying the Exception**:
- **Dacron**: Dacron is formed from the monomers ethylene glycol and terephthalic acid through a process called condensation polymerization. In this process, small molecules (like water) are eliminated during the formation of the polymer.

4. **Conclusion**:
- Since Dacron is formed via condensation polymerization and not addition polymerization, it is the correct answer to the question of which is not an example of an addition polymer.

### Final Answer:
**Dacron is not an example of an addition polymer.**

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