Wool Fibre Structure and Morphology
topic
Wool exhibits complex hierarchical structure: epicuticle (lipid layer 3-5 nm thick providing hydrophobicity and friction), cuticle (overlapping scales 0.5-1.0 μm thickness, 5-7 layers creating directional friction effect—felting), cortex (90% of fibre, ortho and para-cortical cells with intermediate filaments embedded in matrix, creating bilateral structure responsible for crimp), and medulla (air-filled cells in coarser fibres >40 μm). Diameter: 15-45 μm (Merino 17-23 μm), length: 50-350 mm, crimp: 5-15 crimps/cm.
Role
The unique scale-cortex-medulla structure provides wool's characteristic properties: scales enable felting (used in non-woven textiles), bilateral cortex creates natural crimp (bulk, elasticity, insulation), and complex protein structure provides moisture absorption and resilience.