Front Cover: Polymer reaction engineering offers the theoretical background for the modeling pathway from polymerization process conditions to polymer microstructure and end‐use properties. This pathway consists of concrete steps: (i) connection of reaction conditions to polymer microstructure, (ii) connection of microstructure to first level properties, and, (iii) estimation of second level properties as a function of microstructure and/or first level properties. This is reported by Vasileios Touloupidis, Gerold Rittenschober, and Christian Paulik in article 2000028.

applications (from building and construction to automotive, packaging, and medical applications). The humble polymer consisting of building blocks of ethylene, propylene and α-olefins is actually far from being simple, able to be formulated under infinite combinations of the inter-and intramolecular distributions that describe it. Polymer reaction engineering (PRE) offers the theoretical background for describing the catalytic olefin polymerization process. The scope is to develop a modeling pathway from polymerization process conditions to polymer microstructure and end-use properties. This enables us not only to better understand the process but also to establish a mathematical tool for predicting the reactor and the polymer performance under different reaction conditions. This PRE pathway consists of concrete and well-defined steps (Figure 1): [3] The scope of polymer reaction engineering (PRE) is to develop a modeling pathway from polymerization process conditions to polymer microstructure and end-use properties. The catalyst is the heart of the low-pressure polymerization and its kinetic parameters constitute the cornerstone of this pathway, without which none of the modeling steps can be established. In this work, an integrated PRE methodology for capturing the reaction performance of single-and multi-site type catalysts is presented. According to the methodology proposed, the catalyst kinetic parameters are estimated based on a series of targeted bench-scale polymerization experiments and characterization combined with polymer reaction engineering modeling.