纺丝条件及纺丝液组成对丝素-丝胶蛋白同轴干纺纤维的影响

Effect of Spinning Conditions and Dope Composition on Dry-Spun Coaxial Fibers from Regenerated Silk Fibroin-Sericin Aqueous Solution

为了模仿家蚕的纺丝工艺及天然蚕丝的组成和皮芯结构,利用同轴干法纺丝技术制备了以再生丝素蛋白(RSF)为芯层、丝胶蛋白(SS)为皮层的RSF-SS纤维。研究了卷绕速率及芯层纺丝液中RSF质量分数对纤维形貌、2级结构及力学性能的影响。结果表明:复合纤维具有明显的皮芯结构;相对于RSF的质量分数,卷绕速率对纤维结构和性能的影响更明显。当卷绕速率从1 cm/s增至5 cm/s时,纤维直径逐渐减小,β-折叠构象含量增加,但卷绕速率为3 cm/s时纤维的力学性能最佳。随着芯层纺丝液中RSF质量分数的减小,纤维的直径逐渐减小,β-折叠构象含量和断裂强度增加,而初始模量、断裂伸长及断裂能均略有降低。

To biomimic the spinning process of silkworm,the composition and the core-shell structure of natural Bombyx mori silk,regenerated silk fibroin-sericin（RSF-SS） fibers with a core（RSF）-shell（SS） structure were prepared using coaxial dry-spinning process.The effect of take-up 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 core-shell structures.Compared to the mass fraction of RSF in core dope,the take-up rate significantly affected the secondary structure and the mechanical properties of the coaxial dry-spun RSF-SS fibers.The diameters decreased and the content of β-sheet conformation of the coaxial fibers increased when the take-up rate increased from 1 cm/s to 5 cm/s.The fibers with the best mechanical properties were obtained at a take-up 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 β-sheet 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.