Which pair of functional groups must be present on the monomers used to form a polyester?

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Question

Which pair of functional groups must be present on the monomers used to form a polyester?

Accepted Answer

Hydroxyl (–OH) and carboxyl (–COOH) — A polyester is formed by condensation polymerisation between a diol (containing two –OH groups) and a dicarboxylic acid (containing two –COOH groups), releasing water each time an ester linkage (–COO–) forms. Option B describes the monomers for a polyamide, not a polyester. Option C describes a combination that does not produce an ester linkage. Option D describes an aldehyde-acid combination that does not form a polyester at IGCSE level.

Answer

Hydroxyl (–OH) and carboxyl (–COOH)

Answer

Hydroxyl (–OH) and amino (–NH2)

Answer

Amino (–NH2) and carboxyl (–COOH)

Answer

Aldehyde (–CHO) and carboxyl (–COOH)

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