Papadopoulos Periklis, Ene Roxana, Weidner Immanuel, Kremer Friedrich
Universität Leipzig, Institut für Experimentelle Physik I, 04103 Leipzig, Germany.
Macromol Rapid Commun. 2009 May 19;30(9-10):851-7. doi: 10.1002/marc.200900018. Epub 2009 Apr 15.
Minor and major ampullate spider silks are studied under varying mechanical stress by static and time-resolved FT-IR spectroscopy. This enables one to trace the external mechanical excitation on a microscopic level and to determine for the different moieties the time dependence of the molecular order parameters and corresponding band shifts. It is concluded that the hierarchical nanostructure of both types of silk is similar, being composed of highly oriented nanocrystals, which are interconnected by amorphous chains that obey the worm-like chain model and have a Gaussian distribution of pre-strain. By that it is possible to describe the mechanical properties of both silks by two adjustable parameters only, the center and width of the distribution. For major ampullate silk, the observed variability is small in pronounced contrast to the findings for minor ampullate.
通过静态和时间分辨傅里叶变换红外光谱法，在不同机械应力下对小壶腹蛛丝和大壶腹蛛丝进行了研究。这使得人们能够在微观层面追踪外部机械激发，并确定不同部分分子有序参数的时间依赖性以及相应的谱带位移。得出的结论是，两种类型蛛丝的分级纳米结构相似，均由高度取向的纳米晶体组成，这些纳米晶体由遵循蠕虫状链模型且具有高斯预应变分布的无定形链相互连接。由此，仅用两个可调节参数，即分布的中心和宽度，就可以描述两种蛛丝的力学性能。对于大壶腹蛛丝，观察到的变异性很小，这与小壶腹蛛丝的研究结果形成了鲜明对比。
