Which of the following polymer can be used for lubrication and as an insulator?

Options

A. `SBR`
B. `PAN`
C. `PTFE`
D. `PVC`

Answer

To determine which polymer can be used for lubrication and as an insulator, we will analyze the given options based on their properties.

### Step 1: Identify the polymers listed in the options.
The options provided are:
1. Styrene butadiene rubber
2. Polyacrylonitrile
3. Polytetrafluoroethane
4. Polyvinyl chloride

### Step 2: Understand the requirements.
The polymer must have two specific properties:
- It should be a good lubricant.
- It should act as an insulator.

### Step 3: Analyze each polymer option.
1. **Styrene butadiene rubber**: This is primarily used in tires and does not have significant insulating properties.
2. **Polyacrylonitrile**: This polymer is mainly used in textiles and does not exhibit good lubrication or insulation.
3. **Polytetrafluoroethane (Teflon)**: This polymer is known for its low friction properties, making it an excellent lubricant. It also has high electrical resistance, making it a good insulator.
4. **Polyvinyl chloride (PVC)**: While it has some insulating properties, it is not typically used for lubrication.

### Step 4: Conclusion.
Based on the analysis, **Polytetrafluoroethane (Teflon)** is the polymer that meets both criteria of being a lubricant and an insulator. Therefore, the correct answer is **option C: Polytetrafluoroethane**.

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