Deduce Structure of Condensation Polymer Product from Given Monomers

polyamides and polyesters contain diff. linkages and are formed from diff. monomers.

Polymer	Formula and Type of Linkage	Monomers
Polyamide
Polyester

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Forming Polyamides

when monomers of dicarboxylic acid and diamine are combined, polyamides are formed. in polymerisation → water is eliminated. water is formed from the $-OH$ of the carboxylic group and the $-H$ from the amine group. monomers are linked together by amide linkages.

hence in repeat unit → we see functional group (image below) in the middle → while dicarboxylic end will have the $-OH$ removed from the $-COOH$ group and the diamine end will have the $-H$ removed from the $N{H}_2$ group.

therefore if the monomers are: the repeat unit will then be:

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Forming Polyesters

when monomers are dicarboxylic acid and diol are combined → polyesters are formed. in polymerisation → water is again eliminated. water is formed from the $-OH$ of the carboxylic group and the $-H$ from the hydroxyl group. monomers are linked together by ester linkages.

hence in repeat unit → we see that functional group (image below) in the middle, while the dicarboxylic end will have $-OH$ removed from $-COOH$ group and the diol end will have the $-H$ removed from the $-OH$ group.

Therefore if monomers are: the repeat unit will be:

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