Electrospinning was used to fabricate regenerated silk fibroin nanofiber (ERSF) mats with fiber diameter range 50～1000nm. Degummed Bombyx mori silk was dissolved in a ternary solvent system of CaCl2/CH3CH2OH/H2O in 1∶2∶8 mole ratio at 60℃,and lyophilized SF was dissolved in 98% formic acid to obtain regenerated SF solution for electrospinning. The diameter distributions of ERSF spun at various spinning conditions were investigated. 7wt% was a critical concentration of SF solution for better spinnability at a special vol-tage and distance from the tip of capillary to the collector screen (C-SD). The fiber diameter increased with a concentration but decreased with a C-SD, and more uniform SF nanofibers were obtained at a larger C-SD. The effect of voltage on the ERSF was also investigated. When voltage was above a certain value, electrospun regenerated SF nanofibers became thin and even. 50-150nm electrospun SF accounted for about 80% at the spinning conditions of 9wt% concentration, 12cm C-D and 15KV voltage. The mat was treated by methanol or acetone to decrease its contraction in water. Mechanical properties are important for the practical use of the ERSF mats, thus we measured the stress-strain behaviors of the as-spun and chemical treated mats.%采用静电纺丝的方法研制了再生丝素纳米纤维(ERSF)膜,纤维直径为50～1000nm.将脱胶后的桑蚕丝溶解在摩尔比为1:2:8 的60℃CaCl2/CH3CH2OH/H2O三元体系中,将该溶液冷冻干燥后溶解在98%的甲酸中得到再生丝素溶液,对其进行静电纺丝.研究了不同纺丝条件下,静电纺再生丝素纤维的直径分布.研究发现:在一定的电压和喷丝头与接收屏的距离(C-D)下,7wt%是具有良好可纺性的临界浓度.纤维的直径随着溶液浓度的增加而增大,随着C-D的增加而减小,并且在C-D较大时可以获得较均匀的纤维.电压是另一个影响纤维直径的重要因素,当电压高于某一数值时,可以纺得细而均匀的纳米级再生丝素纤维.在9wt%,12cm C-D and 15KV 的纺丝条件下,80%的纤维直径在50～150nm之间.由于所纺得的再生丝素纤维膜在水中会产生收缩,因此用甲醇和丙酮对其进行处理.力学性能是影响纤维膜实际使用的重要性能,我们测定和分析了静电纺再生丝素纤维膜处理前后的力学性能.
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