Which of the following is a homopolymer?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → PAN
A homopolymer is made from a single type of monomer; a copolymer is made from two or more different monomers. PAN (polyacrylonitrile, Orlon) is obtained by addition polymerisation of acrylonitrile alone:
\( \ce{nCH2=CHCN} \xrightarrow{\text{peroxide catalyst}} \ce{-(CH2-CH(CN))_{n}-} \)
So PAN is a homopolymer.
Why the other options are incorrect
Option (1) Buna-N — Incorrect. A copolymer of 1,3-butadiene and acrylonitrile.
Option (3) Dacron — Incorrect. A polyester (Terylene) made from ethylene glycol and terephthalic acid, a copolymer formed by condensation.
Option (4) Bakelite — Incorrect. A condensation polymer of phenol and formaldehyde.
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic is not there in the latest NCERT book (2026-27), and it is also out of the CUET 2026 syllabus.
NCERT (Pre-rationalised edition, 2022-23):
Addition Polymers
