Thixotropic liquids

Thixotropic liquids are fluids that become thinner over time under the constant influence of mechanical forces (shear stress). This effect is based on the destruction of the structure of the fluid, due to which small interactions occur between the particles.

Mechanical forces can be, for example, stirring, kneading, shaking or pumping. Only when the acting forces are suspended do these fluids return to their original viscosity (i.e. toughness). The longer the fluid has been subjected to the forces, the longer it will take to recover to its original viscosity. Fluids that no longer fully regain their original viscosity are called partially thixotropic.

Clear examples of thixotropic fluids from practice are ketchup, toothpaste, margarine or shaving cream.

By the way, the opposite of thixotropic fluids are rheopexic fluids. Their viscosity increases over time with the use of forces. After releasing the forces, it decreases again.

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