Q.What are the monomeric repeating units of Nylon-6 and Nylon-6,6?

Nylon-6: formed by the ring-opening (self-)condensation polymerisation of a single monomer, caprolactam. Its monomeric repeating unit in the polymer chain is:

The '6' in the name refers to the six carbon atoms in the caprolactam ring/monomer.

Nylon-6,6: formed by condensation polymerisation of two different bifunctional monomers, hexamethylenediamine ($H_2N-(CH_2)_6-NH_2$) and adipic acid ($HOOC-(CH_2)_4-COOH$), with loss of water at each amide linkage. Its repeating unit is: …

Recall that Nylon-6 is a self-condensed single monomer (caprolactam) while Nylon-6,6 condenses two distinct 6-carbon monomers (a diamin …

• Writing Nylon-6's repeat unit with 6 CH2 groups instead of 5 (the '6' refers to total ring carbons including the carbonyl carbon, so the CH2 count in the repeat unit is 5). …