# A pharmaceutical company uses condensation polymerisation to produce polyamide fibres for use in surgical sutures (stitches that dissolve inside the body). Explain why polyamides are classed as condensation polymers and describe the structural requirements of the monomers needed to form them.

> OCR A-Level Chemistry B: Salters (H433) — 6.2 Nitrogen compounds, polymers and synthesis · Explain · 5 marks

> Polyamides are a group of condensation polymers. Unlike addition polymers, they are formed when monomers containing two functional groups react together, releasing small molecules in the process. Surgical sutures made from polyamides are designed to break down naturally inside the body over time.

## Mark scheme (5 marks)

1. Condensation polymerisation involves monomers joining together and losing/releasing small molecules
2. Water is named as the small molecule released
3. Each monomer must contain two functional groups (bifunctional monomers)
4. One type of monomer (or both ends of the same monomer) contains an amine/–NH₂ group that reacts with the other functional group
5. The other functional group is a carboxylic acid/–COOH group, which reacts with the amine group to form the amide bond/link

## Key terms

- [condensation polymerisation](https://www.gradenine.co.uk/glossary/condensation-polymerisation)
- [monomer](https://www.gradenine.co.uk/glossary/monomer)
- [polyamide](https://www.gradenine.co.uk/glossary/polyamide)

## Related

- [Revision notes for OCR A-Level Chemistry B: Salters (H433)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/a-pharmaceutical-company-uses-condensation-polymerisation-f5152fbb) · Published by Druglandscape Ltd.