Which of the following polymers have vinylic monomer units

Options

A. Acrilan
B. Nylon
C. Polystyrene
D. Neoprene

Explanation

To determine which of the given polymers have vinylic monomer units, we first need to understand what a vinylic monomer is. A vinylic monomer is characterized by the presence of a vinyl group, which is represented as CH2=CH-. This means that the monomer has a double bond between two carbon atoms, with one of the carbons being attached to another group.

### Step-by-Step Solution:

1. **Identify the Vinylic Group**:
- The vinylic group is defined as CH2=CH- where the CH2 is bonded to another group.

2. **Analyze Each Polymer**:
- **Acrylonitrile (A)**:
- The monomer for acrylonitrile is CH2=CH-CN.
- This structure clearly contains a vinylic group (CH2=CH-), so acrylonitrile has vinylic monomer units.

- **Nylon (B)**:
- Nylon 6-6 is made from hexamethylenediamine and adipic acid, which leads to a structure that does not contain a vinylic group.
- Therefore, nylon does not have vinylic monomer units.

- **Polystyrene (C)**:
- The monomer for polystyrene is CH2=CH-C6H5 (where C6H5 is the phenyl group).
- This structure contains a vinylic group (CH2=CH-), so polystyrene has vinylic monomer units.

- **Neoprene (D)**:
- Neoprene is derived from chloroprene, which has the structure CH2=CCl-CH=CH2.
- This structure contains two vinylic groups (CH2=CH- and CH=CH2), so neoprene has vinylic monomer units.

3. **Conclusion**:
- The polymers that have vinylic monomer units are **A (Acrylonitrile)**, **C (Polystyrene)**, and **D (Neoprene)**.
- Therefore, the answer is A, C, and D.

### Final Answer:
The polymers that have vinylic monomer units are **A (Acrylonitrile)**, **C (Polystyrene)**, and **D (Neoprene)**.

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