Ca2+ crosslinking sodium alginate/graphene oxide composite fiber with enhanced mechanical strength and fire retardancy

• Published in: Journal of the Textile Institute 2023-07, Vol.114 (7), p.1070-1077
• Main Authors: Ma, Jianhua, Song, Baiqing, Li, Xinfeng, Zhang, Tianyi, Liu, Tao, Dang, Yunzhi, Tian, Guangming
• Format: Article
• Language: English
• Subjects: Calcium ions; Crosslinking; fiber; Graphene; graphene oxide; Mechanical properties; Physical properties; reinforcing mechanism; Sodium alginate; Spinning (materials); Strength testing; Wet spinning
• ISSN: 0040-5000; 1754-2340
• DOI: 10.1080/00405000.2022.2109112

It is crucial to enhance the mechanical properties to realize the application of sodium alginate (Alg) in engineering materials. Herein, a Ca 2+ cross-linked sodium alginate/graphene oxide (CAlg/GO) composite fiber with a secondary reinforcement structure was prepared via wet spinning. The microstructure and physical properties of the fibers were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, and mechanical strength testing. The composite fiber's strength and toughness improved significantly, benefiting from the uniform distribution of GO in the Alg matrix together with the simultaneous cross-linking of Ca 2+ to Alg and GO sheets. Accompanying the addition of GO reaching 15%, the strength increased by 184 ± 16%. Meanwhile, the CAlg/GO composite fiber possessed a significant improvement in flame retardancy; the limiting oxygen index increased from 33 to 37 after adding 10% GO sheets to the fiber. In addition, the composite fiber's reinforcement, toughening, and flame retarding mechanisms were discussed from the point of the interaction between Alg, GO, and Ca 2+ , as this study will provide data and theoretical reference for the application of high-performance CAlg/GO composite fiber.