Which of the following is not a synthetic rubber ?

Options

A. Neoprene
B. SBR
C. Thiokol
D. Orlon

Answer

To determine which of the following is not a synthetic rubber, we will analyze each option provided in the question.

### Step 1: Identify the options
The options given are:
1. Neoprene
2. Styrene-Butadiene Rubber (SBR)
3. Thiochol
4. Orlon

### Step 2: Analyze each option
1. **Neoprene**:
- The monomer for neoprene is chloroprene (C4H5Cl).
- Neoprene is a synthetic rubber used in various applications such as wetsuits and gaskets.
- **Conclusion**: Neoprene is a synthetic rubber.

2. **Styrene-Butadiene Rubber (SBR)**:
- SBR is made from the polymerization of styrene and butadiene.
- It is widely used in tires and other rubber products.
- **Conclusion**: SBR is a synthetic rubber.

3. **Thiochol**:
- Thiochol is produced from the polymerization of 1,2-Dichloroethane and sodium polysulfide.
- It is not commonly recognized as a synthetic rubber but rather as a polymer with different properties.
- **Conclusion**: Thiochol is not classified as a synthetic rubber.

4. **Orlon**:
- Orlon is a synthetic fiber made from polyacrylonitrile (PAN).
- It is primarily used in textiles and is not a rubber.
- **Conclusion**: Orlon is not a synthetic rubber.

### Step 3: Identify the correct answer
From the analysis:
- Neoprene, SBR, and Thiochol are synthetic rubbers.
- Orlon is not a synthetic rubber.

### Final Answer:
The option that is not a synthetic rubber is **Orlon**.

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