In situ Investigation of Structural Changes during Deformation and Fracture of Polymers by Synchrotron SAXS and WAXS

By simultaneous mechanical characterisation and synchrotron wide‐angle x‐ray scattering (WAXS) and small‐angle x‐ray scattering (SAXS), it is possible to characterise on‐line local changes in a polymer's structure with a rather‐high time and space resolution, together with the mechanical properties. In this contribution, we discuss the experimental requirements for such investigations as well as three examples. The evolution of structural features during tensile deformation of a polyethylene copolymer, as depicted by WAXS (top) and SAXS (bottom) are shown in the figure. The deformation leads to a martensitic transformation from the orthorhombic to monoclinic system and the formation of nanocavities.