Which of the following sets contains only thermoplastics ?

Options

A. Glyptal,Melmac,`PAN`
B. Polythene,Bakelite,Nylon-`6`
C. `PVC,PMMA`,Polystyrene
D. Polypropylene,Urea-formaldehyde ,Teflon

Answer

To solve the question "Which of the following sets contains only thermoplastics?", we will follow these steps:

### Step 1: Understand the Classification of Polymers
Polymers can be classified into four main categories based on their properties:
- **Elastomers**: These are elastic materials that can be stretched. Examples include rubber and neoprene.
- **Fibers**: These have high tensile strength and are characterized by strong intermolecular forces, such as hydrogen bonding. Examples include nylon and polyesters.
- **Thermoplastics**: These have intermediate strength and can soften upon heating and harden upon cooling. Examples include polyethylene, polystyrene, and polyvinyl chloride.
- **Thermosetting Plastics**: These are cross-linked polymers that become infusible upon heating and cannot be remolded. Examples include Bakelite and urea-formaldehyde resins.

### Step 2: Identify Thermoplastics
From the classification, we need to focus on identifying thermoplastics. The key characteristics of thermoplastics are:
- They can be reshaped upon heating.
- They have linear or branched long chains.

### Step 3: Analyze the Given Options
Now, we need to examine the options provided in the question to identify which set contains only thermoplastics.

### Step 4: Evaluate Each Option
1. **Option A**: Check if it contains any elastomers or thermosetting plastics.
2. **Option B**: Check for the presence of fibers or thermosetting plastics.
3. **Option C**: This option lists polyvinyl chloride, polymethyl methacrylate, and polystyrene. All of these are thermoplastics.
4. **Option D**: Check for any elastomers or thermosetting plastics.

### Step 5: Conclusion
After evaluating the options, we find that **Option C** contains only thermoplastics (polyvinyl chloride, polymethyl methacrylate, and polystyrene). Therefore, the correct answer is:

**Correct Answer: Option C**

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