5.3.4 - polyesters

Question 1

what is a polyester

Answer 1

a polymer made up of lots of molecules joined together in a chain by ester groups

Question 2

to make a polyester what two types of monomer do you need to mix

Answer 2

• dicarboxylic acid (has -COOH at both ends)
• diol (has -OH at both ends)

Question 3

condensation polymerisation:

Answer 3

1) it usually involves two different types of monomer
2) the monomers react together and bonds form between them, making polymer chains
3) each monomer has to contain at least 2 functional groups, one on each end of the molecules
4) each functional group can react with the functional group of another monomer, creating long chains of alternating monomers.
for each new bond that forms, a small molecules (eg. water) is lost

Question 4

to work out the structure of the repeat unit what should you do

Answer 4

highlight the OH in the -COOH groups and the H in the -OH groups and get rid of them
then join what’s left together

Question 5

biopolyesters:

Answer 5

some polyesters are biodegradable, meaning microbes such as bacteria and fungi can use enzymes to break down the polymer into its monomers and use them as an energy supply

this is a good thing, because it reduces out reliance on landfill and incineration to dispose of used polymers