|Combined methods are developed in our institut, sometimes even one-time world-wide: They offer unique advantages for the analysis of complex materials.
Combined with rheology (Rheo) they offer the access to previously unreachable correlations between mechanical properties and molecular parameters, e.g. topology or molecular dynamics.
Combined with size exclusion chromatography (SEC) they are able to connect chemical properties with the size of the polymeric molecules. One example is whether or not the molecular composition of copolymers is independent of chain length.
Rheo - NMR (NMR-Relaxation-Spectroscopy)
Rheo - Dielec (Dielectric Spectroscopy)
Rheo-Dielectric: Fully advanced Rheometer & Dielectric Spectroscopy
Commercial Rheometer (ARES G2 or DHR) / Dielectric Analyzer, Novocontrol / Own Sample geometries
Contact Person: Figuli, Roxana
Correlated information about local mobility (size scale nm-range) and mechanical properties under the influence of shear. Also conductive materials can be analyzed with this method. Examples are e.g. isolating materials or the macroscopic alignment of phase separeted blockcopolymers.
Rheo - IR (Infrared Spectroscopy)
Rheo-IR: Fully advanced Rheometer & IR Spectroscopy
Commercial Rheometer (ARES G2 or DHR) / Own ATR Cystal / Bruker Matrix IR spectrometer
Contact Person: Radebe, Nonkululeko
Correlated information about chemical properties and mechanical properties. You can follow the time velocity profile of chemical changes under load. Examples are kinetics of polymerisation, crosslinking of rubber or hardening of epoxides or the analysis of fresh concrete.
SEC - IR (Infrared Spectroscopy)
SEC-IR: SEC Chromatography & Chemical information via IR-spectroscopy
SEC-System PSS / Own Flow Cells / Own software / Bruker Vertex 70 IR Spectrometer
Contact Person: Pollard, Michael
Correlated information about molecular size and chemical composition. Application example: Chemical composition of blockcopolymers as a function of molecular weight. One part of the self-developed 3-dimensional spectroscopy: dim1:Size via SEC, dim2: chemical composition via SEC-FTIR or SEC-NMR, dim3: topology, endgroups via SEC-IR-QCL.
SEC - IR - QCL (Infrared-Laser Spectroscopy)
SEC-QCL: SEC & IR-spectroscopy based on quantum cascade lasers
SEC System PSS / Self-construction in cooperation with MG Optical solutions and neoplas GmbH
Contact Person: Pollard, Michael
Correlated information about molecular size and special chemical groups. Application example: Amount of rare functional groups (at the moment: 1 Carbonyl group in a polymer of 500.000 g/mol), in future also planned for determination of endgroups and bracnhing units.
One part of the self-developed 3-dimensional spectroscopy: dim1:Size via SEC, dim2: chemical composition via SEC-FTIR or SEC-NMR, dim3: topology, endgroups via SEC-IR-QCL.
SEC - NMR (Medium Field NMR Spectroscopy)
SEC-NMR: 1H-NMR Spectroscopy (Medium-Field) combined with SEC
Magritek Spinsolve 80 / PSS SEC-System / Own capillaries / Own Software
Contact person: Matz, Markus
The Magritek Spinsolve 80 NMR spectrometer sets a new standard for benchtop NMR instruments. The combination with self-developed flow capillaries and newly designed evaluation software, e.g. for solvent suppression, allows for the first time the determination of NMR-Spectra online in the SEC-fractionation process, and this with the use of normal, non-deutrerated solvents.
This combination offers a correlated information about chemical composition and molecular size of polymers, espsecially important for complex polymers or copolymers.