A5011850811- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Organometallic Complex Synthesis and Catalysis
- biodegradable polymer synthesis and properties
- Synthetic Organic Chemistry Methods
- Carbon dioxide utilization in catalysis
- Catalysis and Oxidation Reactions
- Fiber-reinforced polymer composites
- Polymer Foaming and Composites
- Polymer crystallization and properties
- Crystallography and molecular interactions
- Organoboron and organosilicon chemistry
- Inorganic and Organometallic Chemistry
- Asymmetric Hydrogenation and Catalysis
- Polymer composites and self-healing
- Advanced Polymer Synthesis and Characterization
- Lanthanide and Transition Metal Complexes
Covestro (Germany)
2021-2023
RWTH Aachen University
2021-2023
Technical University of Munich
2016-2018
Herein, we present a fundamental study of isostructural 2-methoxyethylamino-bis(phenolate)-lanthanide complexes [(ONOO)RM(X)(THF)] (M = Lu, Y; R tBu, CMe2Ph, X CH2TMS, collidine; THF tetrahydrofuran; TMS trimethylsilyl) for rare-earth metal-mediated group-transfer polymerization (GTP). This analysis includes the differentiation electron-donating and nondonating vinyl monomers two metal centers with regard to ionic radius (yttrium lutetium). In addition, highly nucleophilic alkyl initiators...
Two novel silyl-bridged C2-symmetric (2-methyl-4-aryl-7-methoxy) substituted bisindenyl based ansa-hafnocene complexes of varied steric demand (I, 4-phenyl; II, 4-[(3′,5′-methyl)-phenyl]) were synthesized and examined in the coordinative polymerization propene. Both enable a comparative study with state art homogeneous metallocene catalyst (III, 4-[(3′,5′-tert-butyl)-phenyl]) for high melting ultrahigh molecular weight isotactic polypropylene. All three activated exhibit extremely concise...
This contribution provides the first detailed analysis of nature M–C σ-bond three alkylated, isostructural group 4 (M = Ti, Zr, Hf) metallocenes, thereby elucidating individual peculiarities each metal center in catalytic conversion olefins. Therefore, subtle electronic differences σ-bonds, which are considered crucial for several subprocesses coordinative polymerization olefins, were examined by experimental charge density studies. These studies provided measures increasing ionic character...
Two novel silyl-bridged C2-symmetric 2-methyl-4-aryl-7-methoxy-substituted bis-indenyl-based titanocene complexes with varied steric demand (a, 4-(3′,5′-dimethyl)phenyl; b, 4-(3′,5′-di-tert-butyl)phenyl) were synthesized, characterized, and examined in the coordination polymerization of propene. Both adapted ligand structures have proven their capability as precise catalysts formation stereodefect- regiodefect-free isotactic polypropylene. Several activation pathways to catalytically active,...
The ring opening polymerization of cyclic carbonates made from epoxide and CO2 to CO2-containing polymers constitutes an emerging technology particular industrial interest. Considering the reaction ring-opening ethylene carbonate produce polyethercarbonate polyols, several types catalysts were tested experimentally mechanistic pathways proposed, but a detailed analysis structure property relationship including CO2-liberation is still lacking. This contribution using computational methods...
This contribution provides the simple one-pot, one-catalyst synthesis of high-melting (Tm ∼ 140 °C), high-molecular-weight, elastic polypropylene (ePP) offering an excellent reversible deformation behavior. The produced propylene-based thermoplastic elastomers contain iPP–aPP block structures embedded in amorphous matrix which is enabled by variable stereoselective behavior ethylene-bridged fluorenylindenyl (EBFI) ansa-metallocene complexes. For tailored these ePPs intricate interplay...
Provided is a concept of how the carbon content CO/CO 2 -containing blast furnace gas (BFG) from steel production could be utilized in sequence selective chemical conversion steps to produce high value intermediates for polymer industry.
The production of CO2-containing polymers is still very demanding in terms controlling the synthesis products with pre-defined CO2 content and molecular weight. An elegant way synthesising these via building blocks, such as cyclic ethylene carbonate (cEC), catalytic ring-opening polymerisation. However, to date, mechanism this reaction control parameters have not been elucidated. In work, using DFT-metadynamics simulations for exploiting potential polymerisation process, we aim shed more...
Abstract We report on a solvent‐free approach for the synthesis of low molecular weight, α,ω‐dihydroxy telechelic poly(β‐butyrolactone). In presence Ti(IV) alkoxides, mixtures β‐butyrolactone and diols, like di‐ or triethylene glycol, were reacted in ratios between 4:1 10:1. The oligomerization proceeds at elevated temperatures (80–100°C). Different alkoxide substituents (R = Me, i Pr, t Bu) Ti(IV)(OR) 4 catalyst investigated. resulting oligomers characterized by nuclear magnetic resonance...