Stressed Polymers Change Color
Light-emitting fluorescent dyes that respond to stresses and strains by changing their hue are part of a new polymer blend. Potential uses range from anti-tampering films for packaging to early internal failure sensors according to the polymer scientists who developed the materials at Case Western Reserve University, Cleveland.
"The dyes serve as integral sensors," Weder says. They allow a material's mechanical deformation to be traced through a change in its fluorescence--for example, from red to green. Under UV light, the effect is readily seen by the naked eye.
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