【作者】 周官强；

【导师】 陈新；

【作者基本信息】 复旦大学 ， 高分子化学与物理， 2007， 硕士

【摘要】 近年来,蜘蛛主腺体丝以其优异的综合力学性能受到了人们越来越多的关注,而传统认为力学性能弱于蜘蛛主腺体丝的蚕茧丝,几千年来也一直作为昂贵的纺织材料而闻名。但是,最近的研究结果表明,只要避免聚集态结构上的缺陷,天然蚕丝的力学性能将得到大幅度的提高,甚至接近于蜘蛛主腺体丝。同时,对蜘蛛纺丝过程及其影响因素的深入认识,为结构性蛋白的人工纺丝提供了一定的指导作用。基于以上对天然动物丝的研究,本论文主要以自然界来源广泛的蚕茧(废)丝为原料,制备具有较高浓度的再生丝蛋白水溶液为纺丝液,以硫酸铵水溶液为凝固浴,利用自制的纺丝设备,采用湿法纺丝方法考察了再生丝蛋白纤维工业纺制的可行性以及纤维力学性能提高的空间,以期通过控制丝纤维丝蛋白聚集态结构来制备高性能的丝蛋白纤维。通过对湿法纺丝工艺参数的研究发现,纺丝液浓度对再生丝蛋白纤维的可纺性具有很大的影响,浓度过高或者过低都很难进行纺丝,当浓度为15%左右的时候,再生丝蛋白纤维具有很好的可纺性,并且纤维的表面以及截面的结构形貌较好;凝固浴方面,浓度对再生丝蛋白纤维的截面形状影响较大,温度以及凝固浴槽长度对形成结构致密的纤维具有积极的意义;后拉伸处理方面,比较了空气拉伸和水蒸汽拉伸对纤维的结构与性能的影响,初步提出了适合现有设备的纺丝工艺。在优化的纺丝工艺条件下,成功纺制了聚集态结构良好的再生丝蛋白纤维。通过纤维在形成过程中结构与性能之间的关系,我们发现,经过充分后拉伸处理的再生丝蛋白纤维具有良好的规整性以及分子链取向,性能上超过天然蚕茧丝而接近从蚕体内直接拉出的丝以及蜘蛛主腺体丝。另一方面,通过对经过不同后处理的再生丝纤维的应力-应变曲线进行分析,发现再生丝蛋白纤维在性能上具有很好的可控性。针对以上的研究结果,利用湿法纺丝的原理,引入传质通量比以及固化表面硬度参数对再生丝蛋白纤维的形成机理进行了一定的阐述。同时,根据拉伸过程中纤维结构与性能的变化,初步提出了水蒸汽以及拉伸过程中再生丝蛋白纤维内部微观以及宏观结构变化机理,这将对最终纺制超高性能的再生丝蛋白纤维具有一定的指导意义,同时也可从另一角度理解天然丝纤维的成丝机理。更多还原

【Abstract】 Spider dragline silk has been noted for its excellent comprehensive mechanical properties in recent years, and sikworm silk was used as a luxurious textile material for a long history though it was thought traditionally not as strong as the former. However, from recent research we know that the mechanical properties of silkworm silk can be changed/improved by avoiding the weakness of the structure, and even as high as the spider’s. In other hand, as more and more researches about the spider’s spinning process and other outer conditions have been done, more and more usefull technology will be used on the spinning of regenerated silk fiber.In our experiment, we used the concentrated silk fibroin aqueous solution obtained from the abundant Bombyx mori silk fibers that given by the nature, （NH₄）₂SO₄ aqueous solution as coagulant and a homemade apparatus to produce high-performance regenerated silk fiber by wet spinning in order to examine the feasibility for the spinning of regenerated silk fiber in industry.From the research about the technologic parameters, we found that the concentration of the spinning dope play an important role on the feasibility of spinning. It is hard to spinning when the concentration is too high or too low, when the dope concentration is about 15%, the fiber is spinning continuously and both the surface and cross-section morphology are uniform and pretty well; In the other hand, the fiber’s cross-section shape is most depend on the concentration of coagulant, and the fibers density is also depend on the temperature and the length of coagulation bath. The affect of post-draw under the air and steam conditions to the fibers’ structure and properties were also discussed. And finally found a suitable technologic parameter for the spinning of thr regenerated silk fiber.We succesfully spun the regenerated silk fibers in a continuous process with an optimized technologic parameter. The as-spun fiber is formed with both silk I and silk II structure, with the increase of drawn ratio, the silk I structures converted into silk II structures. In other hand , the molecular chains of the regenerated silk fibers were more inclined to orient along the long axis with increase of the drawn ratio, especially under the steam annealing. The mechanical properties of regenerated silk fiber can been improved by the further treatment, which was superior to the native cocoon silk and close to the force-drawn silkworm silk fibers. In addition, the resulted regenerated silk fibers also presented controllable mechanical properties.Transfer mass ratio and the rigidity of the solidify surface were used to explain the form of the cross-section on the fiber. From the relation between the structure and mechanical property, a drawn mechanism under steam condition was approved.更多还原