4.2 Condensation Polymers

Question 1

Condensation polymerisation (3)

Answer 1

• Condensation polymerisation usually involves two different types of monomer which contain different functional groups. Each monomer contains at least two functional groups.
• The monomers react together and bonds form between them, making polymer chains.
• Each functional group can react with the functional group of another monomer, creating a water molecule.

Question 2

Polyesters

Answer 2

• Polyesters form when dicarboxylic acid monomers and diol monomers react together.
• Polyester fibres are used to make clothes. They can replace natural fibres such as wool and silk.

Question 3

What is an ester link?

Answer 3

The bond between the carbon in the dicarboxylic acid monomer and the oxygen in the diol monomer

Question 4

Polyamides

Answer 4

Polyamides are made from dicarboxylic acid monomers and diamine monomers.

Question 5

What is an amide link?

Answer 5

The bond between the carbon in the dicarboxylic acid monomer and the nitrogen in the diamine monomer.

Question 6

Describe how to find the formulas of the monomers used to make a condensation polymer from its repeating unit

Answer 6

• First find the amide (HN-CO) or ester (CO-O) link. Break it down the middle.
• Then add an H or an OH to both ends of both molecules to find the monomers

Question 7

Describe how to work out the repeating unit of a condensation polymer if you know the formulas of the pairs of monomers (4)

Answer 7

• Draw out the two monomer molecules next to each other.
• Remove an OH from the diacarboxylic acid, and an H from the -NH2 group of the diamine or the -OH group of the diol - that gives you the water molecule.
• Join the C (from the C=O of the dicarboxylic acid) to the N from the amide or the O from the diol.
• Take another H and OH off the ends of your molecule.

Question 8

What is a dimer?

Answer 8

Two monomers combined

Question 9

When is a polymer referred to as a ‘condensation polymer’?

Answer 9

When water is produced as a by-product of the reaction

Question 10

What do the monomers need to make a polyester condensation polymerisation?

Answer 10

The monomers need to have enough carboxylic acid and alcohol functional groups to form a long continuous chain. This means that each monomer needs to have at least two functional groups.

Question 11

Which types of polymers are biodegradable?

Answer 11

Condensation polymers

Question 12

Why are condensation polymers biodegradable?

Answer 12

Ester links can be broken down by microorganisms