Mechanical Properties

Rheometers and universal testing machines are used to measure material properties like shear modulus, viscosity, Young modulus, tensile strength, etc. Commonly studied systems include polymers with complex architectures, nanocomposites, synthetic and biological gels. Various tests are performed to address specific research questions. For example, mechanical spectroscopic measurements are applied for solving problems in which the contribution of particular molecular motions or structural rearrangements in the polymer to the mechanical response of the material are of interest. Rheological measurements are performed in order to characterize flow properties of polymer melts and polymer solutions. Large deformations of polymers in solid or rubbery states are studied in order to deduce deformation mechanisms or quantify the material strength.

References:

Ye LJ, Ji HC, Liu J, Tu CH, Kappl M, Koynov K, Vogt J, Butt HJ: Carbon Nanotube-Hydrogel Composites Facilitate Neuronal Differentiation While Maintaining Homeostasis of Network Activity. Advanced Materials, 2021, 33, 2102981 (doi 10.1002/adma.202102981) Han JX, Xie CM, Huang YS, Wagner MF, Liu WD, Zeng XL, Liu JH, Sun SJ, Koynov K, Butt HJ, Wu S: Ru-Se Coordination: A New Dynamic Bond for Visible-Light-Responsive Materials. Journal Of The American Chemical Society, 2021, 143, 12736-12744 (doi 10.1021/jacs.1c05648)  Agasty A, Wisniewska A, Kalwarczyk T, Koynov K, Holyst R: Macroscopic Viscosity of Polymer Solutions from the Nanoscale. ACS Applied Polymer Materials, 2021, 3, 2813-2822 (doi 10.1021/acsapm.1c00348) Singh M, Hu M, Cang Y, Hsu H-P, Therien-Aubin H, Koynov K, Fytas G, Landfester K, Kremer K: Glass Transition of Disentangled and Entangled Polymer Melts: Single-Chain-Nanoparticles Approach. Macromolecules, 2020, 53, 8562-8569 (doi 10.1021/acs.macromol.0c00550)