We are living in a “Materials World” and consume more polymers than all other types of synthetic materials combined. Polymers are macromolecules having thousands of monomer molecules joined together by covalent bonds. Polymer Reaction Engineering (PRE), or its more recent synonym Macromolecular Reaction Engineering, is originated from chemical reaction engineering. The major task of PRE involves the study of polymerization rate and the design and operation of polymer reactor systems. PRE provides the critical bridge between bench-scale polymer chemistry in lab and full-scale commercial production in industry. It is generally much more complicated than chemical reaction engineering of small molecule products, because of the richness of polymer chain microstructural properties. Therefore, it is often said: “polymers are the products of processes.” Even with the same chemical recipe, a small difference in reactor system design and operation can result in totally different polymer products. The reactor residence time distribution, as well as flow, mass, and heat transport histories, to a large extent, determines the productivity and quality of polymer products. There exists many opportunities through innovation to improve the existing polymers and to develop new polymer products. PRE research is both experimental and theoretical in nature, significantly involving kinetic and process modeling. Why should we have this special issue on “Polymer Reaction Engineering in China?” PRE, as a sub-discipline of Chemical Reaction Engineering, was born in North America and Western Europe. An outstanding group of chemical engineers realized that polymers were much more complicated than small molecule products and that reactor engineering could make huge difference in the chain microstructures and thus in their material properties. A few examples of these pioneers were as follows: Archie Hamielec and John MacGregor (McMaster), Harmon Ray (Wisconsin), Karl-Heinz Reichert (Berlin), Roel Westerterp (Twente), and so on. Much less known were the researchers in the then developing countries like China, such as Professors Zuren Pan and Gan-Tang Chen of Zhejiang University, who started PRE work in the early 1960's, but focused on application-oriented developments. Over the past 30 years, China has been developed into one of the horse powers in the global economy and, so as in the polymer industry, with almost all the major international polymer producers having established significant production and R&D facilities in China. Globalization represents the current trend of our economy and industry. To respond or to lead the trend, this special issue of Macromolecular Reaction Engineering was organized, and so was the “Hangzhou International Polymer Forum” (HIPF). The third HIPF was held in Zhejiang University, Hangzhou, China from May 14–17, 2014 (see the photo). The major theme of the conference was on the development of advanced polymers and polymerization technologies. The first HIPF was in May 14–17, 2007, and the second in May 22–25, 2011. The conference, together with “Polymer Reaction Engineering” (PRE) in North America and “International Workshop on PRE” in Germany, has become one of the PRE conference series in the world, rotating annually around China, Germany, and North America. These conferences are mainly devoted to the exchange of new ideas and views on important issues in PRE among academic scientists and industry practitioners. Considering the success of HIPF-2014 and the rapid development of polymer production industry and research in China, we were requested by the journal Macromolecular Reaction Engineering to organize this special issue on “Polymer Reaction Engineering in China.” The objective is to let the world know better about the Chinese PRE community, as well as giving a glance at what is going on in the polymer production industry in China. It also helps the academic and industrial researchers in China to be better connected to the world PRE community, so that people know who is who and who is good at what. In this special issue, we first invited Prof. Bo-Geng Li of Zhejiang University to contribute a review paper on the development of PRE in China.1 Prof. Li, as a leading figure in the Chinese PRE community, is clearly in the best position for such a review. We also acknowledge him for the successful HIPF conferences. His paper is dedicated to Prof. Zuren Pan, the pioneer of PRE research in China. It provided a great detail about the history and current status of PRE research in China. It can be noted that the polymer industry in China has developed very rapidly over the past 30 years, mainly attributed to the active PRE R&D, as well as the cultivation of high-level talents in Chinese universities. However, the recent focus has started to shift from the pure development to the emphasis of both fundamental and applied research. Polymer industry in China has been booming for decades. Besides the domestic enterprises, almost all the major polymer producers in the world have significant establishments in China, mainly in the areas of Yangtze River Delta and Pearl River Delta. BASF and DuPont are the leading promoters for industrial PRE research. Dr. Gerlinger of BASF stated in his paper2 that the workflow for product development requires a change to meet future sophisticated customer needs. Tailor-made products can only be produced by smart processes, i.e., based on the understanding of structure–property relationships in application. Dr. Leffew of Du Pont used poly(trimethylene terephthalate) as an example and described the development of an industrial polymer platform in China.3 Chinese PRE researchers are active in modeling polymerization processes. In this issue, five papers report modeling work. Prof. Wen-Jun Wang of Zhejiang University reviewed modeling of semi-batch-controlled radical polymerization for the production of copolymers having at-will designed end-to-end composition distribution along backbone.4 This is a major step toward digital synthesis and precision production of polymers. Prof. Zheng-Hong Luo of Shanghai Jiao Tong University modeled continuous atom transfer radical polymerization processes and compared CSTR with plug-flow reactor.5 Prof. Junpo He of Fudan University developed a Monte Carlo method to model free radical polymerization in microflow reactors and studied the effect of flow pattern on polymerization kinetics.6 Prof. Ling Zhao of East China University of Science and Technology modeled the dehydration process and solid-state polymerization of Nylon 6 in drying column.7 Catalysis plays a crucial role in polymer industry. Catalyst development has brought and will continue to bring revolutions in polymer production. While Chinese polymer producers used to import catalysts and acquire technologies from overseas, which is probably still true with high-end polymer products, the PRE researchers in Chinese research institute and universities are very active in catalyst development. Prof. Yi-Xian Wu of Beijing University of Chemical Technology reported her work on fundamental research to industrial application of neodymium-based catalyst for polybutadiene.8 Prof. Boping Liu developed a novel SiO2-supported chromium/vanadium bimetallic catalyst for bimodal polyethylene.9 Dr. Wen-Hua Sun of Institute of Chemistry of the Chinese Academy of Science investigated the performance of a cobalt catalyst in ethylene polymerization.10 Prof. Qinmin Pan of Suzhou University presented a novel method for polybutadiene degradation and diene-based telechelic oligomer synthesis through olefin cross metathesis.11 Besides the modeling of polymerization processes and the catalyst development, researches on new polymer chemistries and technologies, as well as new applications, carried out by some major PRE groups, have also attracted our attention. Prof. Wan-Tai Yang reviewed his systematic studies on obtaining various copolymer products from innovations based on a common reaction of alpha-methylstyrene.12 Prof. Yingwu Luo of Zhejiang University developed an ab initio emulsion polymerization technique by functionalizing surfactant with macro-RAFT agent and compared its performance in MMA and styrene polymerization.13 Prof. Lian-Fang Feng of Zhejiang University reported his work on development of one-step polycondensation process for production of aromatic-containing polyamides.14 Prof. Qiang Yu of Changzhou University employed poly(ethylene-vinylacetate) to encapsulate photovoltaic modules.15 It took a whole year for the preparation of this special issue from its initiative to the realization. It is our hope that this special issue will be highly interesting to our readers and serve the objective to bring the journal Macromolecular Reaction Engineering in closer contact with the Chinese PRE community and vice versa. For this reason, we thank our contributors and those who helped with the reviewing and editing of this special issue of Macromolecular Reaction Engineering on PRE in China. Prof. Shiping Zhu Canada Research Chair in Polymer Reaction Engineering Department of Chemical Engineering McMaster University Hamilton, Ontario L8S 4L8, Canada [email protected] Prof. Shiping Zhu received his BEng from Zhejiang University in 1982 and his PhD from McMaster University in 1991, both from chemical engineering. His PhD supervisor was Professor Archie Hamielec. He is currently a Distinguished University Professor and a Canada Research Chair at McMaster University. He is an elected Fellow of the Royal Society of Canada and Fellow of the Canadian Academy of Engineering. Dr. Zhu's research is on controlled radical polymerization, catalytic polymerization of olefins, kinetic modeling of polymerization processes, surface modification and interfacial engineering, stimuli-responsive polymers and their applications. He has published about 300 refereed journal papers, presented at 200 conferences, and delivered 100 invited seminars around the world. His papers have received over 8000 SCI citations with an H-index of 50. He has trained a hundred postgraduate students and postdoctoral fellows. Dr. Shiping Zhu (standing) with his PhD supervisor Dr. Archie Hamielec in 2015.