Constructing Stiff β-Sheet for Self-Reinforced Alginate Fibers

• Published in: Materials Vol. 17; no. 13; p. 3047
• Main Authors: Xie, Xuelai, Cui, Min, Wang, Tianyuan, Yang, Jinhong, Li, Wenli, Wang, Kai, Lin, Min
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 21.06.2024
• Subjects: alginate fibers; Automation; Calcium chloride; Calcium ions; Coagulation; Contact angle; Crosslinking; degradability; Ethanol; Fibers; Fourier transforms; Mechanical properties; Molecular weight; Polysaccharides; Rheological properties; self-reinforcement; Sodium alginate; Spectrum analysis; Spinning (materials); Tensile strength; β-sheet; United States > US; Japan; Germany
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17133047

The application of alginate fibers is limited by relatively low mechanical properties. Herein, a self-reinforcing strategy inspired by nature is proposed to fabricate alginate fibers with minimal changes in the wet-spinning process. By adapting a coagulation bath composing of CaCl2 and ethanol, the secondary structure of sodium alginate (SA) was regulated during the fibrous formation. Ethanol mainly increased the content of β-sheet in SA. Rheological analysis revealed a reinforcing mechanism of stiff β-sheet for enhanced modulus and strength. In combination with Ca2+ crosslinking, the self-reinforced alginate fibers exhibited an increment of 39.0% in tensile strength and 71.9% in toughness. This work provides fundamental understanding for β-sheet structures in polysaccharides and a subsequent self-reinforcing mechanism. It is significant for synthesizing strong and tough materials. The self-reinforcing strategy involved no extra additives and preserved the degradability of the alginate. The reinforced alginate fibers exhibited promising potentials for biological applications.