Question

Identify monomers used for manufacturing of Terylene?

• A. Propylene glycol and Terephthalic acid
• B. Ethylene glycol and Terephthalic acid
• C. Propylene glycol and Phthalic acid
• D. Ethylene glycol and Phthalic acid

Hint:

Don't mix up Phthalic and Terephthalic acid! Remember that "Terylene" takes its "T" from Terephthalic acid, where the acid groups are at opposite ends (para-position), ensuring a straight, strong fiber chain!

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The problem requires us to identify the specific monomeric building blocks utilized during the industrial manufacture of the synthetic polymer known as Terylene (also widely known as Dacron).

Step 2: Key Formula or Approach:
Terylene is a prominent synthetic polyester. It is produced via a step-growth condensation polymerization reaction between a dihydric alcohol (diol) and a dicarboxylic acid, with the continuous elimination of water or methanol molecules.

Step 3: Detailed Explanation:
The chemical synthesis of Terylene involves heating a mixture of:
1. Ethylene glycol (Ethane-1,2-diol): $\text{HO-CH}_2\text{-CH}_2\text{-OH}$
2. Terephthalic acid (Benzene-1,4-dicarboxylic acid): $\text{HOOC-C}_6\text{H}_4\text{-COOH}$
This reaction is carried out at high temperatures ($420\text{ K}$ to $460\text{ K}$) in the presence of a zinc acetate-antimony trioxide catalyst mixture. The esterification proceeds as follows:
$$n\, \text{HO-CH}_2\text{-CH}_2\text{-OH} + n\, \text{HOOC-C}_6\text{H}_4\text{-COOH} \xrightarrow{\Delta} \left[\text{-O-CH}_2\text{-CH}_2\text{-O-CO-C}_6\text{H}_4\text{-CO-}\right]_n + 2n\, \text{H}_2\text{O}$$ The resulting repeating ester chain forms Terylene. This matches option (B). Note that using phthalic acid (the 1,2-isomer) instead of terephthalic acid (the 1,4-isomer) would yield Glyptal, a completely different polymer.

Step 4: Final Answer:
The monomers used for manufacturing Terylene are Ethylene glycol and Terephthalic acid, corresponding to option (B).