Alginate/graphene oxide fibers with enhanced mechanical strength prepared by wet spinning

Sodium alginate/graphene oxide (NaAlg/GO) fibers were prepared using a wet spinning method. Their structures and properties were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction and mechanical strength testing. The incorporation of GO significantly improved the strength of the NaAlg/GO fibers owing to the uniform distribution of the GO nanosheets in the NaAlg matrix. The maximum tensile strength and Youngʹs modulus increased from 0.32 and 1.9 to 0.62 and 4.3 GPa, respectively, at 4 wt% GO loading. The composite fibers had an even higher strength when they were stretched. The tensile strength increased by 43% over the un-stretched fiber, and Youngʹs modulus increased to 9.39 GPa. In aqueous solution, the GO/NaAlg fibers swelled to form hydrogel fibers that are nontoxic to cells which demonstrated the potential applications of the as-spun fibers in wound dressing materials.