Which of the following is an example of polyester?
Show Hint
- Butadiene-styrene copolymer
- Melamine polymer
- Neoprene
- Poly-\(\beta\)-hydroxybutyrate-co-\(\beta\)-hydroxyvalerate
The Correct Option is D
Solution and Explanation
(1) Butadiene-styrene copolymer (Buna-S): addition copolymer of 1,3-butadiene and styrene, only C-C bonds.
(2) Melamine polymer (melamine-formaldehyde): condensation polymer with C-N (amine/methylene) linkages, not ester.
(3) Neoprene: addition polymer of chloroprene.
(4) Poly-\(\beta\)-hydroxybutyrate-co-\(\beta\)-hydroxyvalerate (PHBV): formed from 3-hydroxybutanoic acid and 3-hydroxypentanoic acid by ester formation (-O-CO-), hence a polyester.
Answer: (4) Poly-\(\beta\)-hydroxybutyrate-co-\(\beta\)-hydroxyvalerate
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