Which of the following is an elastomer?

Options

A. Vulcanized rubber
B. Dacron
C. Polystyrene
D. Malamine

Answer

To determine which of the given options is an elastomer, we need to understand the characteristics of elastomers and analyze each option accordingly.

### Step-by-Step Solution:

1. **Define Elastomers**:
- Elastomers are polymers characterized by their ability to return to their original shape after being stretched or deformed. This property is due to the weak Van der Waals forces of attraction between their linear chains.

2. **Analyze the Options**:
- **Option 1: Vulcanized Rubber**:
- Vulcanized rubber is created by adding sulfur to rubber, which enhances its elasticity. The linear chains in vulcanized rubber have weak Van der Waals forces, making it an elastomer.
- **Option 2: Dacron**:
- Dacron is a type of polyester known for its strength and durability. It has strong hydrogen bonding between chains, which makes it a fibrous polymer, not an elastomer.
- **Option 3: Polystyrene**:
- Polystyrene is a thermoplastic that has moderate forces of attraction, which are stronger than those in elastomers. Therefore, it does not qualify as an elastomer.
- **Option 4: Melamine**:
- Melamine is a thermosetting plastic with strong intermolecular forces, making it more rigid and less elastic than elastomers.

3. **Conclusion**:
- Based on the analysis, the only option that fits the definition of an elastomer is **Vulcanized Rubber**.

### Final Answer:
**Vulcanized Rubber is an elastomer.**