CHEM 121 glossary
Polyester
A condensation polymer whose repeat units are joined by ester links, –CO–O–, formed from a carboxylic acid and an alcohol with loss of water. Water can split these links again (hydrolysis).
Ethyl acetate shows the ester link a polyester repeats along its chain.
Example
PET (recycling code 1, drink bottles and fibres) is made from ethylene glycol and terephthalic acid; its repeat unit is (192.17 g/mol).