Variable Pressure Scanning Electron Microscopy
SEM micrograph of hydrogel pore structure taken in a hydrated state Scanning electron microscopy (SEM) is a powerful imaging technique that can be used to discern morphological features down to nanometers. High energy electrons are focused into a narrow beam with electro-magnets, which then impinge on the sample and scatter backward off the surface. This […]
Filament Stretching Extensional Rheometry
Most polymeric materials exhibit non-Newtonian behavior, meaning that their properties do not behave linearly, and are often strongly rate-dependent. This behavior is strikingly demonstrated in Silly Putty, which flows like a liquid a low deformation rates, and breaks like a brittle solid at high deformation rates. Non-Newtonian behavior in shear flow is often seen as […]