Thixotropic

Thixotropic describes a non-Newtonian fluid that exhibits time-dependent shear thinning; meaning it decreases in viscosity under stress (e.g., stirring, shaking) and returns to a more viscous state when the stress is removed. This property arises from the internal structure of the fluid, where the application of force breaks down the internal bonds, allowing the fluid to flow more easily. When at rest, these bonds re-establish, thickening the fluid. Many paints, gels, and even some foods display this behavior, impacting their application and storage. The term comes from the Greek words 'thixis' (touch) and 'trepein' (to turn or change).

Thixotropic meaning with examples

• When the artist began painting, the thixotropic paint initially flowed smoothly from the brush. As she continued to work, the paint's viscosity decreased, allowing her to create thinner lines with more ease, then, as the paint sat, it thickened again allowing for easy storage.
• The mechanic applied the thixotropic grease to the machinery gears. The vigorous movement of the gears during operation thinned the grease, ensuring it effectively lubricated all surfaces. Upon stopping, the grease returned to its more viscous state, protecting the parts while at rest.
• The chef observed how the thixotropic gravy thinned while being stirred, making it easier to pour over mashed potatoes. Once allowed to rest, the gravy would thicken again, coating the potatoes perfectly.
• The cosmetic company developed a thixotropic gel for hair styling. The gel would readily spread when squeezed and worked in the hands but held the hairstyle firmly upon drying. This gave control and style flexibility.
• The construction crew employed a thixotropic sealant to fill gaps and cracks. Under pressure from the sealant gun, it thinned, flowing into crevices. After application, it thickened providing a durable waterproof seal for the project.