Effects of the alginate and CACL2 concentrations imparting mechanical and morphological properties of wet spun filaments

Abstract

Alginate fibers were used essentially in wound dressing due to his biocompatibility and were prepared by the wet-spinning process using a sodium alginate solution and a calcium chloride solution (CaCl2) as a coagulation bath. The effects of the wet-spinning solvent, coagulating solution, and polymer concentration on corresponding fiber structure were addressed to achieve homogeneous fibers with controlled morphology and suitable mechanical properties. Fiber average diameter, surface state, and fiber homogeneity were assessed by optical and scanning electron microscopies to screen the influence of the formulation and process parameters on the morphological characteristics of the fibers. Furthermore, mechanical properties were studied after determining the monofilament finesses. At an alginate concentration of 8 wt.%, the tenacity and elongation at break of the resulting alginate fibers are the best results. Finally, preliminary studies demonstrated that optimization of CaCl2 concentration and coagulation time resulted in improved fiber regularity and mechanical properties. Thus, optimization of the process and formulation parameters were obtained for a concentration of 8 wt.% alginate, 1 wt.% CaCl2, and a coagulation time of 5 minutes. The resulting spun fibers had an average tenacity of 11 cN/Tex and an average elongation at break of 24%. This is promising for the wet spinning process which can modify the fibers properties.