Physical and Mechanical Characterization of Flax Fibers: From Elementary Fiber to Yarn

Abstract

This study presents a multiscale characterization of flax fibers, from elementary fibers to technical bundles and yarns, to elucidate how fiber scale attributes influence yarn mechanics. Four yarn counts (111.11 tex, 100 tex, 90.9 tex, and 83.33 tex) were produced via dry spinning, and tensile testing performed at each structural level. The results revealed a progressive decline in a specific modulus from elementary fibers (1.09 ± 0.62 N/tex) to short bundles (14.41 ± 9.59 N/tex), primarily due to fiber misalignment. Post hoc analysis confirmed that finer yarns (83.33 tex) exhibited higher stiffness (7.32 ± 1.69 N/tex, p < 0.001), attributed to advanced processing (GN4 combing). These findings highlight the critical role of fiber length and alignment in optimizing flax yarns for high-performance textiles.

Keywords

• flax
• multiscale characterization
• specific modulus
• fineness
• length