学术报告一
报告题目：Living anionic polymerization of 1,4-divinylbenzene and its derivatives
报告人：Prof. Akira Hirao
Tokyo Institute of Technology, National Taiwan University, and Soochow University
时间：2015年6月19日（周五）下午2:30-4:00
地点：独墅湖校区907-1445
Abstract: In general, the anionic polymerization of 1,4-divinylbenzene (DVB) competitively proceeds with the addition reaction of chain-end anion to the pendant double bond leading to chain-branching, followed by the formation of insoluble material by cross-linking. Therefore, DVB is used as the cross-linking agent, but not considered as a typical monomer. Recently, we have successfully demonstrated that DVB undergoes living anionic polymerization in a selective manner through one of the two double bonds with the use of a specially designed initiator system prepared from oligo(a-methylstyryl)lithium and an excess potassium tert-butoxide in THF at -78 oC. With this living polymerization system, well-defined PVDB with Mn values up to 60 500 g/mol and narrow molecular weight distributions (Mw/Mn < 1.05) and block copolymers with styrene, 2-vinylpyridine, and tert-butyl methacrylate were successfully synthesized. Thus, a long-time problem is solved. Details will be presented in my talk.
References: A. Hirao et al., Macromolecules 2011, 44, 5638; 2013, 46, 146; 2014, 47, 2333; 2015, 48, 2370, and 2015, 48, in press.
学术报告二
报告题目：Precise synthesis of multiarmed and multicomponent asymmetric star-branched polymers by iterative methodology based on living anionic polymerization
报告人：Prof. Akira Hirao
Tokyo Institute of Technology, National Taiwan University, and Soochow University
时间：2015年6月24日（周三）上午10:00-11:30
地点：独墅湖校区907-1445
Abstract: The star-branched polymers with structural asymmetry have recently paid much attention because of the formation of unique three-dimensional nano-ordered suprastructures and supramolecular assemblies due to the star-branched architecture and, therefore, have been believed to be the next generation multiphase polymers to block polymers. However, the synthesis of such asymmetric star-branched polymers having different arms is far more difficult than that of regular stars having the same number of arms, since multistep selective and quantitative nature of reactions and multifunctional core compounds with different reactivities are required. In order to overcome such synthetic difficulty, we have recently developed a novel conceptual iterative methodology. The methodology is designed in such a way that the arm introduction, followed by regeneration of the same reaction site, in each reaction process and this process is repeatable. With this methodology, a variety of quite new multicomponent m-star polymers with well-defined structures, such as 5-arm ABCDE, 6-arm ABCDEF, 7-arm ABCDEFG, 9-arm A3B3C3, 7-arm AB2C4, 15-arm AB2C4D8, and 31-arm AB2C4D8E15 types, have been successfully synthesized. Needless to say, they cannot be synthesized by any other methods.
Review papers: A. Hirao et al., Prog. Polym. Sci., 2011, 36, 323. Polym. Chem., 2011, 2, 1219. Eur. Polym. J., 2013, 49, 2545. Macromolecules 2014, 47, 1883.
学术报告三
报告题目：Precise synthesis of high-generation dendrimer-like star-branched polymers, the next-generation hyperbranched polymer, by means of living anionic polymerization
报告人：Prof. Akira Hirao
Tokyo Institute of Technology, National Taiwan University, and Soochow University
时间：2015年6月26日（周五）下午2:30-4:00
地点：独墅湖校区907-1445
Abstract: Dendrimer-like star-branched polymers (DSP) have emerged since 1995 as a novel class of structurally well-defined hyperbranched polymers. The DSPs are highly ordered and regularly branched polymers and, therefore, differentiated from many already-synthesized hyperbranched polymers by their structural perfection. In order to aid the understanding of specific hyperbranched architectures of DSPs, a typical fifth-generation (5G) DSP composed of five layers and the same generation block copolymer with layers/generations which are superimposed (dotted lines) are shown below.
As can be seen, these polymers are very similar in branched architecture to dendrimers, but composed of many polymer chains that are linked to each other between the junctions in all layers. Accordingly, DSPs are much higher in molecular weight and much larger in molecular size than dendrimers of the same generation and believed to be nano-scale globular macromolecules. These polymers have many characteristic structural features, such as specific topological hyperbranched architectures, hierarchical generation-based (or layered) structures, different branch densities between core and outermost layer, and many junctions and chain-end groups that are capable of carrying many functional groups and molecules.
Dendrimer-like star-branched block polymers composed of different segments introduced at each generation have also been synthesized as the new type block polymers composed of hierarchical generation-based block structures. Their thermodynamically immiscible different segments may possibly be phase-separated at the molecular level, followed by self-organizing, to produce quite newly ordered periodic suprastructures and supramolecular assemblies that should be different from those formed by linear block polymers and even mixed arm star-branched polymers having chemically different arms.
Thus, DSPs and their block polymers may become promising specialty functional polymers with many potential applications in the field of nanoscience, such as nano-size reactors carrying enzymes and catalysts arranged along the layers, multicompartment micelles carrying drugs and genetic materials, scaffolds for further branched polymer synthesis, and shape-persistent nanoscale electronic and optical devices.
In this talk, the synthesis of precisely controlled DSPs by means of living anionic polymerization and several characterization results in bulk and solutions are introduced.
CV:
Akira Hirao was born on December 4th, 1947. He received his Doctorate Degree from Department of Chemical Engineering, Tokyo Institute of Technology, Japan, in March, 1975. After post-doctoral work in the USA for two years, his professional carrier started at the Tokyo Institute of Technology progressed from Assistant Professor (1977-83), Associate Professor (1983-96), to Full Professor (1996-2013). He was the Chairman of Polymeric and Organic Materials Department four times, Vice-Dean two times, and the Head of Faculty. He became an Emeritus Professor of Tokyo Institute of Technology from April, 2013.
He has been working in the area of polymer synthesis since 1975. His research interests are focused on the following areas: synthesis and living anionic polymerization of new functional monomers, precise synthesis of architectural polymers such as multiblock polymers, exactly defined graft polymers, high-density comb-like polymers, chain-end- and in-chain-multi-functionalized polymers, multiarmed and multicomponent star-branched polymers, and high-generation and high-molecular-weight dendrimer-like star-branched polymers, and surface nanostructure control and analyses using well-defined perfluoroalkyl polymers.
In recent years, he received the Japan Polymer Society Award (2010), the best award in polymer science in Japan, the Publication Award from the Society of Rheology (USA) (2011), and the Outstanding Achievement in Polymer Science and Technology Award from the Japan Polymer Society (2014). He is now a fellow academia in the Japan Polymer Society. He was members of the Editorial Board of “Macromolecules”, “Polymer Journal” and is currently members of “Macromolecular Research”, “European Polymer Journal”, “Chemical Materials” and others. He was nominated by project leaders in four bilateral (USA, France, Korea two times) collaboration projects supported by both governments. He organized eleven international symposia as (co)organizers. He has published more than 300 papers in peer reviewed journals, such as Macromolecules, J. Am. Chem. Soc., J. Org. Chem., J. Chem. Soc., Chem. Commun., Polymer Chemistry, Macromolecular Rapid Commun., Prog. Polym. Sci., etc., 20 book chapters (and two co-editors), and given 80 keynote, plenary, and invited lectures at international conferences and more than 300 invited talks and lectures in Japan (~200 times) as well as overseas (~100 times) including Polymer Society, Chemical Society, Universities, and companies.
He is now a Distinguished Chair Professor of National Taiwan University, Chair Professors of Soochow University and National Chiao Tung University, and Visiting Professors of Pohang University of Science and Technology (Postech), Fudan University, and King Abdulla University of Science and Technology (KAUST, Saudi Arabia) to deliver lectures for a few years.
（报告联系人：赵优良老师）
