Which one is a copolymer?

Options

A. PVC
B. Polypropene
C. Polystyrene
D. Glyptal

Explanation

To determine which of the given options is a copolymer, we first need to understand the definitions of copolymers and homopolymers.

### Step-by-Step Solution:

1. **Define Copolymer and Homopolymer**:
- A **copolymer** is a polymer that is made from two or more different types of monomers.
- A **homopolymer** is a polymer that is made from only one type of monomer.

2. **Analyze Each Option**:
- **Option A: PVC (Polyvinyl Chloride)**:
- The monomer for PVC is vinyl chloride. It consists of repeating units of the same monomer (vinyl chloride). Therefore, PVC is a homopolymer.

- **Option B: Polypyrene**:
- Polypyrene is derived from the monomer pyrene. Similar to PVC, it consists of repeating units of the same monomer (pyrene). Thus, polypyrene is also a homopolymer.

- **Option C: Polystyrene**:
- The monomer for polystyrene is styrene. It is made up of repeating units of styrene only, making it a homopolymer.

- **Option D: Glyptal**:
- Glyptal is formed from two different monomers: ethylene glycol and phthalic anhydride. Since it is made from two different types of monomers, glyptal is classified as a copolymer.

3. **Conclusion**:
- Based on the analysis, the only option that qualifies as a copolymer is **Option D: Glyptal**.

### Final Answer:
The copolymer among the given options is **Option D: Glyptal**.

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