Acid-catalyzed in-situ cross-linking of polyol on sodium alginate to improve its strength and hydrophobic properties

Abstract

To simultaneously improve the strength and hydrophobicity of alginate-based fibers, a new wet spinning strategy for preparing alginate ester fibers (AE) based on esterification reaction with polyols as in-situ crosslinking agents through acid catalysis is proposed. The esterification was confirmed by FTIR and NMR. XRD analysis showed that the crystallinity of AE fiber increased by 235%. The test results of mechanical properties showed that the modulus has seen an increase of 41.18% and strength an increase of 78.4%. Interestingly, the contact angle was found to increase from 54.6° to 121.9°. Moreover, the influences of polyol types (Ethylene glycol, Glycerol, Pentaerythritol) on the properties of AE fiber are also investigated, the types of polyol have obvious influences on the mechanical properties, crystallinity, and hydrophobicity in AE fibers. These results indicate that this strategy provides a broad application space for alginate-based materials.