TIT# Nanostructure Evolution Mechanisms During Slow Load-Cycling of Oriented
     HDPE/PA Microfibrillar Blends as a Function of Composition
AUT# Zeinolebadi, Ahmad; Stribeck, Norbert; Ganjaee Sari, Morteza;
     Dencheva, Nadya; Denchev, Zlatan; Botta, Stephan;
SOU# Macromol. Mater. Eng. (2012), http://dx.doi.org/10.1002/mame.201100375
LOC# xv132
CLA#
COM#
APP#
MAT#
ABS# Oriented precursors of microfibrillar reinforced composites (MFC) are
     studied during strain-controlled slow load-cycling by small-angle X-ray
     scattering (SAXS). The samples contain high-density polyethylene (HDPE)
     and polyamide 6 (PA6) or polyamide 12 (PA12). Some samples contain
     10 wt.-% compatibilizer. SAXS probes the response of the nanofibrillar
     semi-crystalline entities from the HDPE microfibrils. In the PA6-containing blends
     strongly retarded nanostrain response is detected. It is suppressed by compatibilization.
     Compatibilization induces nanostrain heterogenization in the experiment.
     Stress fatigue is lower in the PA12-blends, but hardly decreased by compatibilizer.
     Selective migration of compatibilizer into a disordered semi-crystalline fraction of
     the HDPE matrix explains the findings. The semi-crystalline HDPE entities in PA6-
     blends appear more disordered than in PA12-blends. An analysis of the HDPEnanostructure
     evolution during cycling reveals epitaxial strain crystallization and
     other mechanisms. Respective evolution cycles are sketched. Uncompatibilized
     PA6-blends cycled about high pre-strain show plastic flow but nanoscopic shrinkage
     in the semi-crystalline stacks that may be explained by extinction of frozen-in
     tensions around the stacks.