Question

Which from following polymers is classified fibres depending on inter molecular forces?

• A. Vulcanized rubber
• B. Buna-S
• C. Terylene
• D. Polystyrene

Hint:

Fibres are polymers with strong intermolecular forces (e.g., hydrogen bonding, dipole-dipole interactions) that allow polymer chains to align closely, leading to high tensile strength and flexibility for drawing into threads.

Answer 1

The Correct Option is A

Step 1: Classification of polymers Polymers are classified based on the nature of intermolecular forces between their chains. Fibres are a class of polymers characterized by strong intermolecular forces such as hydrogen bonding, dipole--dipole interactions, and van der Waals forces. These forces allow the chains to align closely, forming strong and flexible threads.
Step 2: Analysis of given options

• A. Vulcanized rubber: It is a cross-linked elastomer formed by treating natural rubber with sulfur. It exhibits elasticity and cannot be drawn into fibres. Hence, not a fibre.
• B. Buna-S: It is a synthetic rubber (elastomer) made from styrene and butadiene. It shows elastic properties and is used in tyres. Not a fibre.
• C. Terylene: It is a polyester (polyethylene terephthalate, PET). Strong intermolecular forces and linear structure allow close packing of chains, making it suitable for fibre formation. Hence, it is a fibre.
• D. Polystyrene: It is a thermoplastic polymer that is rigid and brittle. Weak intermolecular forces prevent fibre formation. Hence, not a fibre.

Step 3: Conclusion Among the given options, only Terylene satisfies the characteristics of a fibre. \[ \boxed{\text{Terylene \]