Probing the impact of linear deformation on local meso-scale nanofibrillar self-assembly of bagworm silk by X-ray nanodiffraction

Silk threads spun by bagworms (Psychidae) show superb mechanical properties, resulting from a highly ordered fibrillar organization. The SAXS/WAXD analyses using nanoscale X-ray beam for a single bagworm silk (performed at ESRF, ID-13 beamline during SC5011and 5259) resolved an anisotropic structural feature made of a radial gradient in diameters of mesoscale nanofibrillar assembly. However, influence of such radial heterogeneity of mesoscale nanofibrillar assembly on the mechanical properties of bagworm silk has not been known. In order to clarify the influence of radial structural heterogeneity on the mechanical properties, we will conduct a dynamic SAXS/WAXD measurements using nanoscale X-ray beam during the single fiber stretching in this proposal, and we aim clarifying how the radial heterogeneity of mesoscale structural order affect on the superb mechanical properties of bagworm silk.