Abstract:
To biomimic the spinning process of silkworm, the composition and the coreshell structure of natural Bombyx mori silk, regenerated silk fibroinsericin (RSF-SS) fibers with a core (RSF)shell (SS) structure were prepared using coaxial dryspinning process. The effect of takeup rate and mass fraction of RSF in core dope on the morphology, the secondary structure and the mechanical properties of the fibers were investigated. Results showed that the RSF-SS composite fibers had coreshell structures. Compared to the mass fraction of RSF in core dope, the takeup rate significantly affected the secondary structure and the mechanical properties of the coaxial dryspun RSF-SS fibers. The diameters decreased and the content of βsheet conformation of the coaxial fibers increased when the takeup rate increased from 1 cm/s to 5 cm/s. The fibers with the best mechanical properties were obtained at a takeup rate of 3 cm/s. The decreasing of the mass fraction of RSF in core dope resulted in a diameter decrease of the coaxial fiber, and increase of the content of βsheet conformation and the breaking stress of the fibers. However, the initial modulus, the breaking strain and the breaking energy of the fibers only decreased slightly.