An Introduction to Tribo-Rheometry: Quantifying Friction Tribology complements rheology, providing information on solid-solid interactions that adds insight to the bulk fluid measurements of rheology. Tribology is especially concerned with quantifying the coefficient of friction as a function of sliding speed and load force, under dry or lubricated conditions. This provides useful information about lubrication, wear,…
Rheo-Microscopy: Bridging Rheology, Microstructure & Dynamics The combination of optical microscopy with rheological tests enables direct observation of material structure under shear deformation. This provides critical information that can help understand, predict, and tune the material response under processing, storage, or end-use conditions.
Extensional Rheology & Analytics of Material Characterization OVERVIEW Extensional flows are important to converging and squeezing flows that occur in polymer processing operations such as injection molding, extrusion, blow molding, film blowing and calendering. Uniaxial extensional flow measurement is particularly useful in polymer characterization because it is the ‘strongest’ flow field one can generate with…
Gerald Fuller – Interfacial Rheology OVERVIEW Interfacial rheology dominates the behavior of many complex fluid systems. Whether the system is characterized by a fluid-fluid interface or fluid-air interface, these characteristics influence the behavior of biological systems, oil recovery, personal care products, food and more. Learn about the basic forces that drive interfacial dynamics and stability,…
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…