Polymer Chemistry and Catalysis

Prof. Udo Kragl (University of Rostock)

We are engaged in process development for chemo- and biocatalytic processes. This includes the development of new processes, especially in the field of downstream processing, e.g. with membrane processes, as well as new catalysts and materials. Investigations into scale-up and the optimization of existing processes and procedures with regard to economic and ecological aspects are also the subject of the work. In the field of biocatalysis Dr. Jan von Langermann has habilitated with the concept of in-situ product removal, Dr. Robert Francke in the field of electrocatalysis with the concept of membrane separation of polymer-bound mediators. The research activities at LIKAT are characterized by the junior research group of Dr. Esteban Mejia, who is located at the institute and successfully completed his habilitation in December 2020. The main research areas include silicone-based polymers and polyether-based functional materials.

Literature

[1] F.O. Sommer, J.-S. Appelt, I. Barke, S. Speller, S. U. Kragl, Membranes 2020, 10, 308. UV-Polymerized Vinylimidazolium Ionic Liquids for Permselective Membranes.

[2] J. Claus, A. Brietzke, C. Lehnert, S. Oschatz, N. Grabow, U. Kragl, PLoS ONE 2020, 15, e0231421. Swelling characteristics and biocompatibility  of ionic liquid-based hydrogels for biomedical applications.

[3] L.-E. Meyer, A. Gummesson, U. Kragl, J. von Langermann, Biotech. J. 2019, 14, 1900215. Development of Ionic Liquid‐Water‐Based Thermomorphic Solvent (TMS)‐Systems for Biocatalytic Reactions.

 

Group Dr. Esteban Mejia

Chemistry, as one of the main players of progress and (arguably) the culprit of most of its evils, has been called to tackle these problems, head-on, for which a “complete makeover” on the way chemists design their processes and manage their outcomes was necessary. The paradigm shift came with the development of the concept of “green chemistry” and its twelve principles, having catalysis at its core.

Guided by Green Chemistry’s principles, the application of catalytic technologies towards the development of sustainable processes and products are the main research motivation at the Mejía’s group.

Our main research activities include the development of safe polymerization catalysts for consumer products (silicones), together with novel base-metal systems to produce biodegradable polymers and the sustainable synthesis of CO2-epoxide copolymers.

Furthermore, the development of novel copper-based catalytic systems for the synthesis of enynes and heterocycles, improving over existing technologies, refraining from the use of noble metals and pre-functionalized substrates. These systems include molecular coordination compounds and artificial metalloenzymes.

Metal-free catalyst for aerobic oxidation reactions, including heterogeneous carbocatalysts and persistent radical cations are being developed.

 

Another focus is the synthesis and application of heterogeneous catalysts derived from waste rice husk.  An alternative route for the valorization of agricultural rice bio-waste was established, resulting in high added-value products (the catalysts) with potential immediate impact in the chemical industry.

 

References:

1) Catalytic Aerobic Oxidations, 1st ed. (Ed: Esteban Mejía), Catalysis Series No. 39, Print ISBN: 978-1-78801-720-6, Royal Society of Chemistry, 2020.

2) F. Unglaube, P. Hünemörder, X. Guo, Z. Chen, D. Wang and E. Mejía, Helv. Chim. Acta 2020, 103, e2000184. Phenazine Radical Cations as efficient Homogeneous and Heterogeneous Catalysts for the Cross‐Dehydrogenative Aza‐Henry Reaction.

3) A. Salazar, A. Linke, R. Eckelt, A. Quade, U. Kragl and E. Mejía, ChemCatChem 2020, 12, 3504-3511. Oxidative Esterification of 5‐Hydroxymethylfurfural under Flow Conditions Using a Bimetallic Co/Ru Catalyst.

4) A. A. Almasalma, E. Mejía, Synthesis 2020, 52, 529-536. Allylic C–H Alkynylation via Copper-Photocatalyzed Cross-Dehydrogenative Coupling.