In the polymerization of acrylonitrile, most commonly used initiator is

Options

A. a cation
B. an anion
C. a free radical
D. Zwitter ion

Answer

To solve the question regarding the most commonly used initiator in the polymerization of acrylonitrile, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Acrylonitrile**:
- Acrylonitrile is a compound with the structure H2C=CH-CN. It contains a nitrile group (–CN), which is known to be an electron-withdrawing group.

2. **Type of Polymerization**:
- The polymerization of acrylonitrile is typically carried out through anionic polymerization. This means that the initiation of the polymerization process involves the use of anions.

3. **Identifying the Initiator**:
- In anionic polymerization, a strong base is commonly used as the initiator. This is because strong bases can generate anions that can initiate the polymerization process.

4. **Examples of Strong Bases**:
- Some examples of strong bases that can be used as initiators include:
- Potassium hydroxide (KOH)
- Sodium hydroxide (NaOH)
- Potassium amide (KNH2)
- These strong bases produce anions that can effectively initiate the polymerization of acrylonitrile.

5. **Conclusion**:
- Therefore, the most commonly used initiator in the polymerization of acrylonitrile is an anionic initiator, specifically a strong base.

### Final Answer:
The most commonly used initiator in the polymerization of acrylonitrile is an anionic initiator (strong base).

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