Macromol. Mater. Eng. 10/2017.

Front Cover: The microstructural evolution during creep is investigated by in situ synchrotron small‐angle X‐ray scattering, which could be well distinguished into four stages. During primary creep, strain grows nonlinearly to a value less than 15% is a short time because of elastic deformation. During secondary creep, lamellae thickening could be found. The lamellae thickening rate along loading direction is higher than that perpendicular to the loading direction, indicating that the orientation of molecular chains along the loading direction facilitates the lamellae thickening process. After yielding, the fibrillary structure could be induced by lamellae breaking‐reorganization. The length of the fibrillary structure increases from 364 nm to 497 nm, whereas its width stays at 102 nm as creep time increases. This is reported by Baobao Chang, Konrad Schneider and Gert Heinrich, in article number 1700152. [ABSTRACT FROM AUTHOR]