JEE Advanced levelOne or more correct optionsDifficulty 3 of 3pl067
Which of the following statements about nylon 6,6 are correct?
AIt is formed by step-growth condensation with elimination of water.
BIt can be obtained by ring-opening polymerisation of caprolactam.
CEach repeat unit, −[NH−(CHX2)X6−NH−CO−(CHX2)X4−CO]X−, contains two amide groups.
DHydrogen bonding between amide groups of neighbouring chains helps give fibre-like strength.
Answer: A, C, D
Nylon 6,6 forms from diamine plus diacid with loss of water, giving two amide groups per repeat unit, and inter-chain N-H...O=C hydrogen bonds hold chains together. Ring-opening of caprolactam gives nylon 6, not nylon 6,6.