Mechanisms of elasticity across length scales in textile fiber systems: Chemistry, structure, and applications

Elastic textiles, including fibers, yarns, and fabrics that can reversibly deform, are indispensable across diverse fields, from apparel to soft robotics, wearable electronics, and biomedical systems. Yet, the fundamental understanding of how molecular conformations, fiber architectures, and fabric-scale structures collectively govern elastic behavior remains fragmented across disciplines. This review introduces a novel multiscale design framework that bridges nanoscale mechanisms, such as conformational transitions and soft–hard segment architectures, with microscale and macroscale deformation modes, including protein secondary-structure unfolding and the uncoiling of twisted or coiled yarns. We further discuss integration strategies for macro-structured yarns within woven, knitted, and braided fabrics, emphasizing the interplay between functionality, manufacturability, and durability. By linking molecular-to-textile-scale mechanisms within a coherent framework, this review lays the groundwork for predictive, sustainable, and multifunctional design of elastic materials.