Which of the following are polycarbamate ester polymers?

Options

A. Polyurethane
B. Perlon-`U`
C. Melmac
D. Saran

Answer

To determine which of the given options are polycarbamate ester polymers, we can follow these steps:

### Step 1: Understand the Structure of Polycarbamate Ester Polymers
Polycarbamate ester polymers contain a specific functional group characterized by the presence of the following structure:
- O-C(=O)-NH
This indicates that for a polymer to be classified as a polycarbamate ester, it must have this repeating unit in its structure.

### Step 2: Analyze Each Option
Now, let's analyze the given options one by one:

1. **Polyurethane**:
- The structure of polyurethane includes the repeating unit O-C(=O)-NH.
- Therefore, it qualifies as a polycarbamate ester polymer.

2. **Parallon-U**:
- Parallon-U has a similar structure to polyurethane, also containing the repeating unit O-C(=O)-NH.
- Thus, it also qualifies as a polycarbamate ester polymer.

3. **Melmac**:
- The structure of Melmac does not contain the O-C(=O)-NH group.
- Therefore, it does not qualify as a polycarbamate ester polymer.

4. **Sarin**:
- Sarin also lacks the O-C(=O)-NH linkage in its structure.
- Hence, it does not qualify as a polycarbamate ester polymer.

### Step 3: Conclusion
Based on the analysis, the polymers that qualify as polycarbamate ester polymers from the given options are:
- **Polyurethane**
- **Parallon-U**

### Final Answer:
The polycarbamate ester polymers are **Polyurethane and Parallon-U**.

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