Neoprene is the addition polymer of chloroprene, which is 2-chloro-1,3-butadiene. The conjugated diene adds across its two ends, so the double bond is retained in the middle of each repeating unit and the chlorine remains on the carbon that carried it in the monomer.
nCH2=C(Cl)−CH=CH2→[−CH2−C(Cl)=CH−CH2−]n
The structure of neoprene is the 1,4-polychloroprene chain, a saturated backbone interrupted by one double bond per unit with the chlorine atom attached to one of the doubly bonded carbons.
JEE Main · 2021 · 26 Feb 2021 · Shift 1 · Single correct option