The weakest interparticle forces are present in:

Options

A. Thermosetting polymers
B. Thermoplastic polymers
C. Fibers
D. Elastomers

Answer

To determine which type of material has the weakest interparticle forces, we can analyze the different categories of polymers based on their intermolecular forces. Here’s a step-by-step solution:

### Step 1: Understand the Types of Polymers
Polymers can be classified into four main categories based on their intermolecular forces:
1. **Elastomers**
2. **Fibers**
3. **Thermoplastics**
4. **Thermosetting Plastics**

### Step 2: Analyze Intermolecular Forces in Each Category
- **Elastomers**: These materials have the weakest intermolecular forces. They possess elastic properties and can stretch due to low cross-linking and weak attraction between the polymer chains.
- **Fibers**: Fibers exhibit stronger intermolecular forces, primarily due to hydrogen bonding, which gives them high strength and rigidity.
- **Thermoplastics**: These have intermolecular forces that are stronger than elastomers but weaker than fibers. They can be molded upon heating.
- **Thermosetting Plastics**: These have the strongest intermolecular forces due to a heavily cross-linked structure, making them rigid and heat-resistant.

### Step 3: Compare the Strength of Intermolecular Forces
Based on the analysis:
- **Weakest**: Elastomers (due to weak intermolecular forces)
- **Stronger**: Thermoplastics
- **Stronger Still**: Fibers (due to hydrogen bonding)
- **Strongest**: Thermosetting Plastics

### Step 4: Conclusion
From the classification and analysis, we conclude that the weakest interparticle forces are present in **elastomers**.

### Final Answer
The weakest interparticle forces are present in: **Elastomers** (Option D).

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