OVERVIEW Large amplitude oscillatory shear (LAOS) is used increasingly as a tool to measure the nonlinear viscoelastic responses of soft solids and complex fluids. For many material systems the common practice of reporting only “viscoelastic moduli” (typically corresponding to the first harmonic Fourier coefficients G’1(w), G”1(w)) is insufficient and/or misleading in describing the nonlinear phenomena.…
Jan Vermant – Orthogonal Superposition Rheology OVERVIEW Superposition flows in rheology are powerful methods to understand non-linear and anisotropic viscoelasticity. Parallel Superposition experiments have been historically simple to perform, but are difficult to understand and do not provide all of the desired information. Recent developments have made Orthogonal Superposition more simple to perform, allowing…
Professor Chris Macosko – Analyzing Molecular Weight Distribution w/ Rheology In this TA Instruments Webinar, Professor Chris Macosko discusses analyzing molecular weight distribution and blend morphology using rheology. Rheology is a powerful tool for analyzing polymer blends. This seminar will begin with the simplest case: molten blends of two different molecular weight homopolymers.We will…