Which of the following polymers are used as fibre? (i) Polytetrafluoroethane (ii) Polychloroprene (iii) Nylon (iv) Terylene

Option (iii) and (iv) are the answers.

Because of strong intermolecular interactions such as H-bonding, nylon and terylene are employed as fibres, resulting in tight chain packing and therefore imparting crystalline character.