In which of the following polymers ethylene glycol is one of the monomer units ?

Options

A.
B.
C.
D.

Explanation

To determine which polymers contain ethylene glycol as one of their monomer units, we can analyze the options provided in the question. Here’s a step-by-step solution:

### Step 1: Identify Ethylene Glycol
Ethylene glycol is a diol with the chemical formula \( \text{HOCH}_2\text{CH}_2\text{OH} \). It consists of two hydroxyl (-OH) groups attached to a two-carbon chain.

### Step 2: Understand the Structure of Common Polymers
1. **Glyptal (or Glyptol)**: This polymer is formed from the condensation reaction between ethylene glycol and phthalic acid. The resulting polymer contains ester linkages, which is characteristic of polyesters.
2. **Polyethylene**: This polymer is made from the polymerization of ethylene (C2H4), not ethylene glycol. Therefore, it does not contain ethylene glycol as a monomer.
3. **BUNA-S**: This is a type of synthetic rubber made from the copolymerization of 1,3-butadiene and styrene. Ethylene glycol is not involved in its formation.

### Step 3: Conclusion
From the analysis:
- **Glyptal (Glyptol)** contains ethylene glycol as a monomer unit.
- **Polyethylene** and **BUNA-S** do not contain ethylene glycol as a monomer unit.

Thus, the correct answer is that ethylene glycol is a monomer unit in **Glyptal (Glyptol)**.

### Final Answer:
Ethylene glycol is one of the monomer units in **Glyptal (Glyptol)**.

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