polyesters

• similar to ester reaction
• functional group = O=C-O
• polyester needs a diol and a dicarboxylic acid
• a diol = an alcohol with 2 OH
• a dicarboxylic acid = a carboxylic acid with 2 functional groups
• condensation polymerisation = with diol and dicarboxylic acid = both ends of molecule can react - join together into one long chain = release water
• and ester bridge = the functional group that attaches the molecules together
• repeat unit for polyesters = poly[-----]n + 2nwater