JEE Main levelOne or more correct optionsDifficulty 2 of 3pl135
In which of the following is a small molecule (water) lost in the step that joins the monomers?
ABakelite from phenol and formaldehyde
BPVC from chloroethene
CPolystyrene from styrene
DNylon 6,6 from hexamethylenediamine and adipic acid
Answer: A, D
Polycondensation eliminates a small molecule: water in nylon 6,6 (amide formation) and in phenol-formaldehyde condensation. PVC and polystyrene are addition polymers with no by-product.