Concept:Nylon-6,6 is a synthetic polyamide formed via step-growth condensation polymerization of a six-carbon diamine with a six-carbon dicarboxylic acid.
Formula / Reaction:$$n\,\text{H}_2\text{N}-(\text{CH}_2)_6-\text{NH}_2 + n\,\text{HOOC}-(\text{CH}_2)_4-\text{COOH} \longrightarrow -[\text{HN}-(\text{CH}_2)_6-\text{NH}-\text{CO}-(\text{CH}_2)_4-\text{CO}]_n- + 2n\,\text{H}_2\text{O}$$
Solution:- The monomers required for Nylon-6,6 are hexamethylenediamine (1,6-diaminohexane) and adipic acid (hexanedioic acid).
- The designation '6,6' denotes that both reacting monomer species contain exactly 6 carbon atoms.
Why other options are incorrect:- Sobacoyl chloride: A 10-carbon acyl chloride monomer used in the synthesis of Nylon-6,10.
- Methylene diamine: Contains only 1 carbon atom and does not form Nylon-6,6.
- Heptane-1, 7-dioic acid: A 7-carbon dicarboxylic acid (pimelic acid) not used in Nylon-6,6 synthesis.
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