Harald Wilhelm

Plasticity and X-ray Line Profile Analysis of the semicrystalline polymer poly(3-hydroxybutyrate)

The evolution of the microstructure during compressive deformation of the biodegradable polymer poly(3-hydroxybutyrate) (P3HB) was investigated in-situ via X-ray diffraction using synchrotron radiation. Flow curves were measured in-situ together with X-ray profiles for several degrees of deformation. The profiles were analysed using Multi-Reflection X-ray Line Profile Analysis (MXPA) adapted by the authors for semicrystalline polymers providing lamella thickness, crystallinity, and the presence and density of dislocations as a function of the deformation. In contrast to previous investigations in α crystallised isotactic polypropylene (α-iPP), P3HB does not exhibit a deformation induced increase of the dislocation density which suggests mechanisms other than dislocations to be involved in plastic deformation of P3HB.