Investigation of Coagulant Type Effect on Wet–Spinning Process of Regenerated Silk Fibroin

Document Type : Research Article


Department of Textile Engineering, Faculty of Engineering, University of Guilan, Rasht, Iran


Regenerated silk fibroin (RSF) with various concentrations, 8, 10, 12.5 and 13% (w/w), was dissolved in N-methyl morpholine N-oxide (NMMO) to prepare spinning solutions. The effect of several coagulants such as methanol, ethanol and 1-propanol, and temperatures of spinning, 95, 110 and 120 °C, on the wet spinnability of the silk fibroin solutions were investigated by means of observation of wet spun fibers in various concentrations and coagulant baths (without any post drawing performance) and by measuring their tenacities at break. Undrawn good continuous and bead free fibers with high tenacity and elongation behavior, 1.6 cN/dtex and 34.25% respectively, were obtained at the concentration of 8% (w/w) and temperature of 95 °C and with presenting of methanol coagulant. The results showed that by increasing concentrations in 10, 12.5 and 13%, the tenacity decreases, 0.81, 0.70 and 0.20 cN/dtex, respectively. Tenacity of the fibers obtained in 1-propanol, 0.6 cN/dtex, was lower than those in ethanol, 0.8 cN/dtex, and methanol, 1.6 cN/dtex, coagulation bath. Therefore these results showed that the coagulant chemical type strongly influences the wet spinnability of undrawn regenerated silk fibers.


Main Subjects

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