• Condensation polymers are formed when?two different monomers?are linked together with the?removal?of a small molecule, usually?water
• This is a key difference between condensation polymers and addition polymers:
  • Addition polymerisation forms the polymer molecule?only
  • Condensation polymerisation forms the?polymer?molecule and one?water?molecule?per linkage

   

• The monomers have two?functional?groups present, one on?each end
• The functional groups at the ends of one monomer react with the functional group on the end of the other monomer, in so doing creating long chains of?alternating monomers, forming the polymer
• Polyesters are formed from two different monomers and produce water
• For every ester linkage formed in condensation polymerisation, one molecule of water is formed from the combination of a -H and an -OH group
• An example is terylene which is a?polyester?made from?dicarboxylic?acid monomers (a carboxylic with a -COOH group at?either?end) and?diols?(an alcohol with an -OH group at?either?end)
• Each -COOH group reacts with another -OH group on another monomer
• An ester linkage is formed with the subsequent loss of?one?water molecule per link

The condensation reaction in which the polyester terylene is produced

• The structure of terylene can be represented by drawing out the polymer using boxes to represent the carbon chains
• This can be done for all polyesters

Diagram showing a section of the polyester terylene

The biodegradation of a bottle made of biopolyesters

轉載自savemyexams