Nylon-6 is :

Options

A. Polyamide
B. Polyester
C. Polystyrene
D. Polyvinyl

Explanation

To determine the classification of Nylon-6, we will analyze its structure and the type of linkages present in it. Here’s a step-by-step solution:

### Step 1: Understand the Structure of Nylon-6
Nylon-6 is a type of synthetic polymer. Its monomer is caprolactam, which is a cyclic amide. When caprolactam undergoes polymerization, it forms Nylon-6.

### Step 2: Identify the Functional Groups
In the structure of Nylon-6, we can identify the presence of amide linkages. An amide linkage is characterized by a carbonyl group (C=O) directly attached to a nitrogen atom (N).

### Step 3: Compare with Other Polymer Types
1. **Polyamide**: Contains amide linkages (–C(=O)–N–).
2. **Polyester**: Contains ester linkages (–C(=O)–O–).
3. **Polystyrene**: A polymer made from styrene, does not contain amide or ester linkages.
4. **Polyvinyl**: Refers to polymers made from vinyl compounds, such as polyvinyl chloride (PVC), which also do not contain amide linkages.

### Step 4: Conclusion
Since Nylon-6 contains amide linkages, it is classified as a polyamide. Therefore, the correct answer to the question "Nylon-6 is:" is **polyamide**.

### Final Answer
Nylon-6 is a **polyamide**.

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