Hydrodynamic alignment and microfluidic spinning of strength-reinforced calcium alginate microfibers

Abstract Microfluidic spinning technology (MST) employed for the fabrication of microfibers is an emerging material fabrication method of great scientific interest. To achieve high-strength properties of the fabricated reinforced microfibers, the nanostructure must be tunable. Herein we present a process combining hydrodynamic alignment (HA) and MST to synthesize microfibers with different diameters in a multiphase coaxial flow. The preferential macromolecule orientation along the microfiber forming direction and its diameter was tuned by varying the process parameters. The tensile test revealed that the maximum strength of the fabricated calcium alginate microfiber reached 185.1 MPa, whereas the microfibers were found to have consistent and uniform size with an average diameter of 31.3 μm. Successful HA at higher flow rates prior to gelation caused a decrease in the diameter of the microfiber.