| Bio-macromolecular fibers were used in textile, medicine and biology et al. because of their intrinsic bio-functions. A lot of biomimetic and super biomimetic macromolecular fibers have been produced since the 20th 90's and the study on biomaterials has focused on the new fiber with high strength and low density. Spider silk had excellent mechanical properties that were unique among natural and high performance synthetic fibers, so that a great number of research organizations and scholars were interested in the super biomaterials. Recently, the researchers overseas studied the structures and properties of spider silk. Meanwhile, with the development of biological technology, the artifical protein of spider silk was successfully produced with gene transplanting and the artifical spider silk was spun. However, this silk wasn't industrially produced because of imperfect properties, complex process and high cost.The properties of fiber were determined by molecular structure and morphology from the view of material science. The fundamentally to understand the mechanisms of fiber properties was the study on the principal relationship between structures and properties. It was very important to investigate the structural mechanisms of spider silk properties and know the way to form the structure in order to transplant the mechanical properties of spider silk to artifical bio-macromolecular fibers.Araneus Ventrous spiders abroad distribute to everywhere in China. Some properties of three kinds of the spider silk fibers were studied which were dragline, framework and egg-case silks. These properties were mechanical properties, color and optical characteristics, density and deliquescent effect, thermal properties. On the basis of these, the mechanisms of excellent mechanical properties of the spider silk fibers were investigated on the following aspects.The first was the molecular foundations of mechanical properties of spidersilk fibers. The amino acid compositions were analyzed and compared with that of other species spider silks and Bymox fibroin. It was studied that how the amino acid compositions influenced on the molecular conformations and assignments. The molecular conformations of the spider silk fibers with different functions respectively were investigated by using Laser Raman spectrum and FTIR. The relationships were analyzed between the amino acid compositions, molecular structures and mechanical properties.The second was morphology and micro-shapes' effects on the extra mechanical properties. The crystal and orientation of the spider silk were studied with X-ray diffraction. The configurations of these spider silk fibers were investigated by SEM images and their skin-core and fibril microstructures were found in the cross sections of processed fibers by physical or chemical methods. The reasons were analyzed, which these spider silk fibers with under 10% crystal regions had high strength and strains. The effects of skin-core structure on the mechanical properties were researched and the causes were analyzed that there were some differences in stress-strain behaviors of different functional spider silks.The third was the research on the relationships between the spinning conditions and the molecular structure, mechanical properties of the spider silk. On the basis of the analyzing of biological spinning mechanisms of spider silk, the molecular conformation change was studied in the spinning process and the effects of spinning conditions were investigated on the molecular structure. The active control on properties of spiders was studied with the varieties of environment and spinning way and the relationships were more analyzed between the structure and properties.Finally, the structural models of the spider silk were designed after understanding the key factors of mechanical properties of the fiber. The structures of some peptides contained in the major gland protein were optimized and two models were established, the first was skin-core morphology structure, second was the tensile mechan...
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