Higo Blog

Yes, it's another day in the office working on the dreaded Ashiya curriculum, which means that my brain needs to be exercised lest it die from atrophy. A co-worker brought in some slime and started to play with it, which got me thinking about colloids, gels, polymers, and the properties of substances that exhibit behavioral characteristics of both solids and liquids.

Rheopectic - Rheopecty is the property of some non-newtonian fluids to show a time dependant change in viscosity; the longer the fluid undergoes shear, the higher its viscosity. Rheopectic fluids are a rare type of fluids, in which shaking for a time causes solidification. A common house-hold example is corn flour (also known as corn starch) mixed with water.

Thixotropic -Thixotropy is the property of some non-newtonian pseudoplastic fluids to show a time-dependent change in viscosity; the longer the fluid undergoes shear, the lower its viscosity. However, this is not a universal definition; the term is sometimes applied to pseudoplastic fluids without a viscosity/time component.

Many gels and colloids are thixotropic materials, exhibiting a stable form at rest but becoming fluid when agitated. Some clays are also thixotropic, with their behavior of great importance to structural engineering in earthquake zones. Clayey ground can practically liquefy under the shaking of a tremor, greatly increasing the effect on buildings.

The classic example of a thixotropic fluid is ketchup, where waiting for it to pour can be more effective than pounding on the bottom of the bottle. Thixotropic compounds are important paint additives, allowing a thick, smooth application that doesn't run.

Sometimes it's fun to learn words that, if used out in public, will brand you as a pretentious geek. If you do use them out of their limited context with any seriousness, then you are probably a tool.