Microstings have repeatedly caused plane crash and heavy accidents related to the destruction of bridges and pipelines. That is why the specialists responsible for the operation of complex engineering facilities are faced with the task of discovering them as soon as possible.
Specialists of the University of Illinois, led by professors, Nancy Sotos and Scott Whita, developed a new polymer coating for various structural materials. Its main feature is the ability to change color in the event of the smallest cracks.
The polymer contains epoxy resin microcapsules filled with light yellow pH-sensitive dye. In the absence of damage, the capsule remains untouched. But, as soon as the microcrack appears in the gap area of the gap is released, which immediately reacts with epoxy resin. As a result, a bright red spot appears at the place of damage. The spot increases depending on the size of the crack.
According to researchers, the polymer was already successfully tested on some metals, glass and other polymers. The cost of the coating is low, since it contains only 5 % in microcapsules.
In the future, scientists intend to give the polymer properties of self -healing. That is, at the beginning of the polymer, changing the color “inform” the presence of a crack, and after it “cures” it, will again accept the original color.