Textile Fibres
What the exam tests
Fibre classification, physical and chemical properties, end uses, and simple identification. Expect questions that ask you to match a fibre to a property, or to interpret a burn test.
Core rules
- Natural fibres: cellulosic (cotton, linen, jute) and protein (wool, silk).
- Man-made fibres: regenerated from natural polymers (viscose rayon, modal, lyocell) and synthetic from petrochemicals (polyester, nylon, acrylic, spandex).
- Cotton: absorbent, breathable, wrinkles, burns like paper with grey ash.
- Wool: warm, elastic, felts and shrinks, burns with a burning-hair smell and crushable dark ash.
- Silk: lustrous, strong but loses some strength when wet, burns like hair.
- Polyester: strong, hydrophobic, thermoplastic, melts and forms a hard bead.
Worked example
An unknown grey fabric is absorbent, wrinkles, and when a yarn is burned it smells of burning paper and leaves fine grey ash. Reasoning: the paper smell and grey ash indicate a cellulosic fibre. Because it is soft, absorbent and wrinkles readily, cotton is the most likely answer; linen would feel cooler, stiffer and show longer fibres. A blend cannot be ruled out from burning alone, so a solubility or microscopic test would be needed for confirmation.
Traps
- Calling viscose rayon “synthetic”; it is regenerated cellulosic.
- Treating silk as a plant fibre because it is lustrous.
- Relying on one burn test for a blend; blends often show mixed odour and bead behaviour.