Which is true about Buna-N ?

Options

A. It is a linear polymer of 1,3 - butadiene.
B. It is obtained by copolymerization of 1,3 butadiene and styrene.
C. It is obtained by copolymerization of 1,3-butadiene and acrylonitrile.
D. The suffix N in Buna- N stands for its natural occurrence.

Explanation

### Step-by-Step Solution:

1. **Understanding Buna-N**:
- Buna-N is a type of synthetic rubber known as a copolymer.
- A copolymer is a polymer that is made from two or more different types of monomers.

2. **Identifying the Monomers**:
- The two monomers used to create Buna-N are:
- **1,3-butadiene**: This is a diene with the structure CH2=CH-CH=CH2.
- **Acrylonitrile**: This is a nitrile with the structure CH2=CH-CN.

3. **Formation of Buna-N**:
- Buna-N is formed through the copolymerization of 1,3-butadiene and acrylonitrile.
- The reaction involves the double bonds of both monomers, leading to a long chain structure that incorporates both types of units.

4. **Structure of Buna-N**:
- The resulting structure of Buna-N will have alternating units of butadiene and acrylonitrile, which can be represented as:
- (–CH2–CH=CH–CH2–) and (–CH2–CH–CN–).

5. **Conclusion**:
- Therefore, the correct statement about Buna-N is that it is a copolymer formed from the copolymerization of 1,3-butadiene and acrylonitrile.