Which one of the following polymers may be classified as step growth polymer ?

Options

A. Teflon
B. Polythene
C. PVC
D. Nylon-6, 6

Explanation

To determine which polymer can be classified as a step growth polymer, we first need to understand the characteristics of step growth polymerization.

### Step-by-Step Solution:

1. **Understanding Polymers**:
- A polymer is a high molecular mass substance made up of repeating structural units derived from simple molecules.

2. **Types of Polymerization**:
- There are two main types of polymerization:
- **Addition Polymerization** (also known as chain growth polymerization)
- **Condensation Polymerization** (also known as step growth polymerization)

3. **Characteristics of Step Growth Polymerization**:
- In step growth polymerization, polymers are formed by the condensation of two or more bifunctional monomers with the elimination of small molecules such as water, ammonia, or alcohol.
- Each step in the process produces a distinct functionalized species, and the reactions are independent of each other.

4. **Examples of Step Growth Polymers**:
- Common examples of step growth polymers include polyesters and polyamides.
- Specifically, nylon (like nylon 66) is a well-known example of a step growth polymer.

5. **Identifying the Correct Polymer**:
- From the options provided, we need to identify which polymer fits the criteria of being formed through step growth polymerization.
- Nylon 66 is a polyamide formed through the condensation of hexamethylenediamine and adipic acid, making it a step growth polymer.

6. **Conclusion**:
- Therefore, the correct answer is that nylon 66 is classified as a step growth polymer.

### Final Answer:
Nylon 66 is classified as a step growth polymer.