Florian Spieckermann

Abstract:

Although semicrystalline polymers have become increasingly important for technological applications in the past decades, the micromechanical processes on an atomistic scale occurring during plastic deformation are still a matter of dispute [1]. As an example, this concerns the question whether dislocations in the crystalline phase play a role for the macroscopic strength or not [2]. Based on dedicated experimental methods such Multiple X-ray Line Profile Analysis (MXPA), which allows the verification of the presence of dislocations and their quantification [3-6], and nano-creep experiments, as a mechanical probe for dislocation mediated plasticity with sub-nanometer resolution [7], we discuss recent findings on the molecular processes governing the plasticity of semicrystalline polymers. Special emphasis is given to the generation, mobility, and thermal activation of dislocations in particular, and crystallographic defects and transformations in general for several semicrystalline polymer materials.