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It is well-known that the molar mass distribution (MMD) of block copolymers will be performed by size exclusion chromatography (SEC) with two calibrated detectors to determine the molar mass distribution via the average chemical composition distribution (CCD) of the block copolymers. This work will present a new way to determine the molar mass distribution via the average chemical composition of block copolymers by using the nuclear magnetic resonance (NMR) based diffusion ordered spectroscopy (DOSY) with inverse Laplace transform (ILT). This DOSY approach allows the determination of the MMD of copolymers in the bulk sample. It will be shown that DOSY can be enabled for the determination of the MMD via the CCD of block copolymers by adopting the dual detector SEC approach to DOSY. Therefore, several PS-b-PMMA block copolymers were analyzed by this new DOSY approach as well as the dual SEC-UV-RI detection. The DOSY results of the MMD and CCD are in good agreement with the common SEC-RI-UV dual detector copolymer analysis.

Lubricating greases based on urea thickeners are frequently used in high-performance applications since their invention in 1954. One property that has so far been neglected in the further development of these systems due to their low solubility and the resulting difficulty of analysis, is to better understand how the degree of polymerization affect such polyurea lubricating systems. In this work, we prepared three different oligo- or polyurea systemswith different degrees of polymerization (DP) and investigated the influence of DP on rheological and tribological properties. The results showed that the DP has an influence on the flow limit in rheology as well as on the extreme pressure (EP) and anti-wear (AW) properties as examined by tribology measurements. By optimizing the DP for a thickener system, comparable EP and AW properties can be achieved through the use of additives. The DP showed an increasing influence on the flow limit. This could reduce damage to rolling bearings due to lateral loading at rest. Therefore, modifying the DP of the polyurea systems shows similar effects as the addition of external additives. Overall, this would reduce the use of additives in industrial applications.

Since its introduction in 2004, Knochel's so called Turbo-Grignard reagents revolutionized the usage of Grignard reagents. Through the simple addition of LiCl to a magnesium alkyl an outstanding increase in reactivity can be achieved. Though the exact composition of the reactive species remained mysterious, the reactive mixture itself is readily used not only in synthesis but also found its way into more distant fields like material science. To unravel this mystery, we combined single-crystal X-ray diffraction with in-solution NMR-spectroscopy and closed our investigations with quantum chemical calculations. Using such a variety of methods, we have gained insight into and an explanation for the extraordinary reactivity of this extremely convenient reagent by determining the structure of the first bimetallic reactive species [t-Bu 2 Mg • LiCl • 4 thf] with two tert-butyl anions at the magnesium center and incorporated lithium chloride.