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 analyze each option based on the definition and characteristics of elastomers.

### Step-by-Step Solution:

1. **Understand the Definition of Elastomers**:
- Elastomers are polymers that exhibit viscoelasticity, meaning they have both viscosity and elasticity. They are characterized by weak intermolecular forces, which allow them to stretch and return to their original shape.

2. **Evaluate Each Option**:
- **Option A: Vulcanized Rubber**:
- Vulcanized rubber is a type of rubber that has undergone a process called vulcanization, which involves cross-linking polymer chains. This enhances its elasticity and strength, making it a classic example of an elastomer.
- **Option B: Dexron**:
- Dexron is a trade name for a type of polyester fiber, commonly used in automotive transmission fluids. It is not an elastomer.
- **Option C: Polystyrene**:
- Polystyrene is a thermoplastic polymer that does not exhibit the elastic properties characteristic of elastomers. It becomes soft when heated and hard when cooled, which is typical of thermoplastics.
- **Option D: Melamine**:
- Melamine is a thermosetting plastic that does not soften upon heating. It is used in various applications but does not have the elastic properties of elastomers.

3. **Conclusion**:
- Among the options provided, **Vulcanized Rubber** is the only material that qualifies as an elastomer due to its viscoelastic properties and ability to stretch and return to its original shape.

### Final Answer:
The correct answer is **Option A: Vulcanized Rubber**.

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