# A sportswear manufacturer is researching materials for a new range of lightweight clothing. They are considering using a polyamide produced by condensation polymerisation from two monomers: a diamine and a dicarboxylic acid. Explain how the structure of these monomers allows condensation polymerisation to occur, and describe what happens to the small molecules produced during the reaction.

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

> Polyamides are condensation polymers widely used in performance sportswear. They are formed from monomers that each contain two functional groups.

## Mark scheme (5 marks)

1. Each monomer has two functional groups
2. The diamine provides two amine (–NH₂) functional groups and the dicarboxylic acid provides two carboxyl (–COOH) functional groups
3. Having two functional groups on each monomer allows bonds to form at both ends, enabling a long chain polymer to grow
4. A small molecule (water) is lost / eliminated each time a bond forms between two monomers
5. The bond formed between the monomers is a peptide / amide bond (–CO–NH–), forming a polyamide

## Key terms

- [condensation polymerisation](https://www.gradenine.co.uk/glossary/condensation-polymerisation)
- [monomers](https://www.gradenine.co.uk/glossary/monomers)
- [diamine](https://www.gradenine.co.uk/glossary/diamine)
- [dicarboxylic acid](https://www.gradenine.co.uk/glossary/dicarboxylic-acid)
- [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)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-sportswear-manufacturer-is-researching-materials-d16fa108) · Published by Druglandscape Ltd.