Materials all around us can be classified as either elastic, viscous, or viscoelastic. One can determine where a material falls within the viscosity spectrum based on its rheological properties. With its start in the 1920s, rheology is still an up-and-coming method of characterization for everyday use materials.1 This is because materials such as plastics, paints, biological materials, and more contain both solid and liquid aspects.2 Unlike its counterpart, the viscometer, a rheometer can analyze those materials unable to be defined by a single value of viscosity.3 The official definition for rheology is the science and deformation of flow. It measures stress, strain, and the relation between the two in order to provide quantitative parameters of a material’s deformation.2 Rheology plays a crucial role in industrial production with everything from coatings to pharmaceuticals to foods.4 All stages of a material’s production from manufacturing to transport to storage and eventual use are impacted by its rheological conditions.4 Better understanding of these conditions can allow for improved production methods with more targeted products.
1. Markovitz, H., The emergence of rheology. Physics Today 1968, 21 (4), 23-30.
2. Janmey, P. A.; Schliwa, M., Rheology. Curr Biol 2008, 18 (15), R639-R641.
3. VivaDifferences Difference Between Rheometer and Viscometer. https://vivadifferences.com/difference-between-rheometer-and-viscometer/.
4. Rheology of Semisolid Foods. Joyner, H. S., Ed. Washington State University, USA, 2019.