Which of the following are thermoplastic polymers ?

Options

A. Polythene , urea - formaldehyde , polyvinyls
B. Bakelite , polythene, polystyrene
C. Polythene , polystyrene , polyvinyls
D. Urea - formaldehyde , polystyrene , bakelite

Answer

To determine which of the given options are thermoplastic polymers, we can follow these steps:

### Step 1: Understand Thermoplastic Polymers
Thermoplastic polymers are materials that become pliable or moldable upon heating and solidify upon cooling. They can be reshaped multiple times without undergoing any significant chemical change.

### Step 2: Identify the Given Polymers
The question provides the following polymers:
- Bakelite
- Urea Formaldehyde
- Polythene
- Polystyrene
- Polyvinyl

### Step 3: Classify Each Polymer
Now, we will classify each of these polymers as either thermoplastic or thermosetting:

1. **Bakelite**: This is a thermosetting polymer. It cannot be remolded once it has set.
2. **Urea Formaldehyde**: This is also a thermosetting polymer. Similar to Bakelite, it cannot be reshaped once it has cured.
3. **Polythene (Polyethylene)**: This is a thermoplastic polymer. It can be melted and reshaped.
4. **Polystyrene**: This is a thermoplastic polymer. It can also be melted and reshaped.
5. **Polyvinyl (Polyvinyl Chloride - PVC)**: This is a thermoplastic polymer. It can be melted and reshaped.

### Step 4: List the Thermoplastic Polymers
From the classification:
- **Thermoplastic Polymers**: Polythene, Polystyrene, Polyvinyl
- **Thermosetting Polymers**: Bakelite, Urea Formaldehyde

### Step 5: Conclusion
The thermoplastic polymers among the given options are Polythene, Polystyrene, and Polyvinyl. Therefore, the correct answer is:

**Option 3: Polythene, Polystyrene, and Polyvinyl.**

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