Which is not an example of copolymer?

Options

A. SAN
B. ABS
C. Saran
D. PVC

Explanation

To determine which option is not an example of a copolymer, we need to understand the definition of copolymers and analyze each option provided.

### Step-by-Step Solution:

1. **Understand Copolymers**:
- Copolymers are polymers formed from two or more different types of monomers.

2. **Analyze Each Option**:
- **Option A: San (Styrene Acrylonitrile)**:
- This is formed from two monomers: styrene and acrylonitrile.
- Since it is made from two different types of monomers, it is a copolymer.

- **Option B: ABS (Acrylonitrile Butadiene Styrene)**:
- This polymer consists of three different monomers: acrylonitrile, butadiene, and styrene.
- Therefore, ABS is also a copolymer.

- **Option C: Saran**:
- Saran is made from two monomers: vinylidene chloride and vinyl chloride.
- This qualifies Saran as a copolymer as well.

- **Option D: PVC (Polyvinyl Chloride)**:
- PVC is made from only one type of monomer, which is vinyl chloride.
- Since it is formed from a single monomer, PVC is classified as a homopolymer, not a copolymer.

3. **Conclusion**:
- Among the options, the only one that is not a copolymer is **Option D: PVC**.

### Final Answer:
**Option D: PVC (Polyvinyl Chloride) is not an example of a copolymer.**

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