“Living” Copolymerization of CO2 with Epoxides as a New Approach Towards the Synthesis of Polycarbonates
报告主题：“Living” Copolymerization of CO2 with Epoxides as a New Approach Towards the Synthesis of Polycarbonates
报告人：Professor Yves Gnanou (Dean & Professor of Chemistry Physical Sciences & Engineering Division King Abdullah University of Science and Technology)
Carbon dioxide (CO2) is an abundant, inexpensive, and non-toxic renewable C1 feedstock that is only used in a limited number of product-yielding reactions due to its low reactivity. After the discovery by Inoue et al. of the copolymerization of CO2 and epoxides by diethyl zinc a number of efficient transition metal catalysts functioning by coordinative chemistry have been developed: in the latter case the polymerization occurs by coordination of the epoxide monomer, followed by successive insertions of epoxides and CO2 until a transfer reaction takes place producing aliphatic polycarbonate chains.
In the present lecture we will show that CO2 and epoxides can be copolymerized anionically using classical alkali metal anionic initiators or even metal-free anionic initiators, without resorting to transition metal-based coordinative chemistry used so far. This opens up new horizons for the utilization of CO2 in its anionic copolymerization with epoxides:
1) as perfectly defined polycarbonate telechelics can now be prepared for further use as precursors of polyurethanes,
2) as very high molecular weight polycarbonates samples can be generated due to the “living” nature of the copolymerization,
3) as diblock and triblock copolymers can be easily obtained and thus thermoplastic elastomers generated by sequential addition of two different epoxides,
4) as various functional polycarbonates can be derived by copolymerizing under “living” conditions functional epoxides with CO2 .
So far CO2 has been uniquely used in anionic polymerization for carbonation purpose of living carbanionic chains by R. Quirk; we demonstrate here that it can be anionically copolymerized with epoxides, provided a Lewis acid is added to specifically activate the epoxide monomer.
Professor Yves Gnanou is the Dean for Physical Sciences and Engineering (PSE). Professor Gnanou joined KAUST from the École Polytechnique in Paris where he held the role of Vice President of Academic Affairs and of Research.
Prior to that, he successively held the position of Professor and Director of the “Laboratoire de Chimie des Polymères Organiques” (LCPO) at Bordeaux University (France) and Head of the Chemistry Department at the headquarters of the “Centre National de la Recherche Scientifique” (CNRS) in Paris. During his tenure in Bordeaux he was also Adjunct Professor at the University of Florida from 2002-2007 and a Visiting Professor at the Massachusetts Institute of Technology (MIT), Cambridge, USA from 1989-1990.
Professor Gnanou received his PhD in Polymer Chemistry in 1985 from the L. Pasteur University (Strasbourg). His research interests currently focus on the design of metal-free “green” catalysts for chain and step-growth polymerizations and on the assembly of original polymeric architectures by novel synthetic methods.
In 2003 Professor Gnanou received the Langevin Prize and the Berthelot Medal from the French Academy of Sciences and in 2009 was elected as a Member of the French Academy of Agriculture.
In 2011 he was awarded the Title Chevalier dans l’ordre des Palmes Académiques and in 2013 he was awarded the Title Chevalier dans l’Ordre des Palmes Acad.