Branching Design in Polyolefins by Catalyst Variation. Theory meets experiment

• Applicants: Professorin Dr. Albena Lederer; Professor Dr. Jens-Uwe Sommer
• Subject Area: Experimental and Theoretical Physics of Polymers ; Preparatory and Physical Chemistry of Polymers
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 267690214

• Final Report Year: 2021

Final Report Abstract

Walking Catalysts possesses the unique feature of randomly moving along the structure of the synthesized molecule in between successive reaction events. Combining synthesis, analysis techniques and theory and simulations we have shown that this leads to macromolecules with novel topological properties. In particular, structure corresponding to the class of dendritic bottle-brushes has been predicted and obtained in experiments. The reaction parameters could be linked to structural properties which open new pathways to design advanced macromolecular structures on demand. This project is the basis for further collaboration between the German and the Czech partner, which is the subject of a present Humboldt-Fellowship and DFG project proposal. During the 30th anniversary (30.09.2019) of the West German Minister of Foreign Affairs Hans-Dietrich Genscher legendary speech from West German embassy’s balcony in Prague, Czech Republic, this research project has been presented to non-scientific audience. In dialog with politicians the Czech-German collaboration has been appreciated as valuable international and interdisciplinary research collaboration combining synthesis, experiment, and theory across borders.

Publications

• „Effect of ligand backbone substituents of nickel α‐diimine complexes on livingness/controllability of olefin polymerization: Competition between monomer isomerization and propagation“ J. Polym. Sci. A: Polym. Chem. 2016, 54(19), 3193-3202
  A. Sokolohorskyj, R. Mundil, A. Lederer, J. Merna
  
• „Multicore unimolecular structure formation in single dendritic-linear copolymers under selective solvent conditions.”, Macromolecules 2016, 49 (23), 9215-9227
  M. Wengenmayr, R. Dockhorn, J.-U. Sommer
  
• “α-Keto-ß-diimine nickel catalyzed olefin polymerization: Effect of ortho-aryl substituents and preparation of stereoblock copolymers” J Polym Sci A 2017
  A. Sokolohorskyj,O. Zeleznık,I. Cısarova, J. Lenz, A. Lederer, J. Merna
  
• “High Temperature Quadruple-Detector Size Exclusion Chromatography for Topological Characterization of Polyethylene” Anal. Chem., 2018, 90 (10), 6178–6186
  L. Plüschke, R. Mundil, A. Sokolohorskyj, J. Merna, J.-U. Sommer, and A. Lederer
  
• “On the topology of highly branched polyethylenes prepared by amine-imine nickel and palladium complexes” Polym. Int. 2018
  R. Mundil, S. Hermanová, M. Peschell, A. Lederer, J. Merna
  
• olyolefins Formed by Chain Walking Catalysis—A Matter of Branching Density Only? J. Am. Chem. Soc. 2019
  R. Dockhorn, L. Plüschke, M. Geisler, J. Zessin, P. Lindner, R. Mundil, J. Merna, J.-U. Sommer, A. Lederer
  
• “Topology Analysis of Chain Walking Polymerized Polyethylene: An Alternative Approach for the Branching Characterization by Thermal FFF” Macromolecules 2019, 52 (22), 8662–8671
  M. Geisler, William C. Smith, Laura Plüschke, Robert Mundil, Jan Merna, S. Kim Ratanathanawongs Williams, Albena Lederer
  
• “Fractionation of Chain Walking Polyethylene and Elucidation of Branching, Conformation and Molar Mass Distributions “ IJPAC 2020
  L. Plüschke, A. Ndiripo, R. Mundil, J. Merna, H. Pasch, A. Lederer
  
• “Unraveling Multiple Distributions in Chain Walking Polyethylene Using Advanced Liquid Chromatography“ Macromolecules 2020, 53, 10, 3765-3777
  L. Plüschke, A. Ndiripo, R. Mundil, J. Merna, H. Pasch, A. Lederer
  
• „The Role of Solubility in Thermal Field Flow Fractionation – A Revisited Theoretical Approach for Tuning the Separation of Chain-Walking Polymerized Polyethylene”Anal Chem 2020
  M. Geisler, L. Plüschke, J. Merna, A. Lederer