Discussion of the CDF Patterns

Nanostructure of the unstrained samples. The left column displays the CDFs of the samples at = 0. Most prominent are the layer-like peaks on the meridian of the CDFs. They describe the stacked crystalline and amorphous layers of the polypropylene matrix and their correlation in straining direction. Their lateral extension is a measure of the average lateral extension of the layers. These reflections are analyzed quantitatively in Sect. 5.6. It is worth reminding that the meridional SAXS peaks reflected in the CDF only probe the part of the matrix volume that is flUed by semicrystalline stacks with a minimum arrangement among their constituent domains (ordered stacks). Random placement of irregular domains does not generate discrete SAXS peaks. 

The CDF in the top left corner shows the pure PR Compared to the blend and the composites below its peaks are wider in horizontal direetion. Thus the lamellae are wider than those of the samples that contain MMT. Moreover, several distinct reflections are piled up. This shows that the thickness variation of the layers is low, and at least 3 crystalline lamellae are correlated in each stack. In the samples containing MMT the correlation along the stack is even lower. There are only 2 crystalline layers in each stack (a sandwich )- Arrows point at the shape distributions hcadru, rj) of such sandwiches. For the pure PP hcacirn, 3) is narrow in r3-direction. Thus the heights of aU sandwiches are almost the same. In the lateral ri2-direction the peak is extended. Thus the sandwich is made from two crystalline lamellae that are well-aligned on top of each other. 

All the CDFs of the MMT samples show an off-meridional, vertically extended intensity region. This intensity characterizes the distance distribution between the left and the right edge of microfibrils that house the crystalline domains. For pure PP this peculiar arrangement of crystalline domains is not observed. 

---