Front Cover: In this work, a modeling pathway and software tool for linking entangled linear polymer molecular properties to linear viscoelasticity and melt index (MI) values is presented. A reptation model links molecular properties to the flow curve, and then, an ANSYS Polyflow model calculates MI values based on the flow curve predicted. The method is thoroughly tested and validated for uni‐and bi‐modal, low‐ and high‐density polyethylene grades. An overall accuracy level in the range of 90% on average is exhibited, considering both model prediction steps: (i) MWD to flow curve and (ii) flow curve to MI. These promising results offer a valuable tool to enhance product development toward the direction of end‐use polymer bulk properties prediction. Further details can be found in the article by Vasileios Touloupidis,* Christof Wurnitsch, Alexandra Albunia and Girish Galgali on page 392.

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Cover: CFD calculations of the gas flow in a microreactor led to installation of an overflow. With a video microscope the polymerizations are followed and the surface morphology of the derived PE particles is analyzed by SEM. The effects of the installed overflow on growth kinetics and morphology are compared with polymerizations in static conditions. Further details can be found in the article by L. Mayrhofer, A. Krallis, C. Wurnitsch and C. Paulik http://doi.wiley.com/10.1002/mren.201400031.

The presented micro gas-phase reactor is a very suitable tool for the investigation of polymerizations. To achieve conditions which are closer to industry an overflow is installed in the microreactor. With this setup it is now possible to have a distinct exchange of ethene during the polymerization. CFD calculations have been performed to evaluate the reactor setup and according to these results the reactor has been modified to allow an exchange of the reactor volume two times per minute. The overflow leads to a better heat removal from the growing polymer particles and supplies the active centers with preheated ethylene. The performed overflow-polymerizations are compared with polymerizations in static conditions and the results allow deeper understanding of the polymerization kinetics on particle level in gas phase conditions.