High-strength carrageenan fibers with compactly packed chain structure induced by combination of Ba²⁺ and ethanol

Carrageenan fibers have attractive applications in textile, but their low strength remains a problem that needs to be urgently addressed. In this work, a novel facile, environmental friendly method for fabricate high-strength carrageenan fibers is proposed. It involves the crosslinking of a small amount of Ba²⁺ ions in the carrageenan solution, followed by using recyclable alcohol in coagulation and stretching baths. Carrageenan molecular chains were allowed to first sufficiently interact with metal barium ions, and then were stretched and dehydrated with alcohol to increase the hydrogen bonding interaction between the molecular chains. As a result, the carrageenan fibers with high-strength ionic and hydrogen bonds were obtained. The fibers obtained by the novel method had high tensile strength at 1.63 cN/dtex, which is two times higher than that of those obtained by the traditional process.