system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do most plastics turn white when you bend them?
gpt
First of, this phenomenon only occurs for a certain kind of plastics. When you deform those by bending or stretching them to the point where they won't revert to their original shape, you induce permanent deformations that change the microstructural organisation of the molecules that the plastic is made of. This causes the formation of voids or very small bubbles in the plastic. Those voids grow in number and size and there comes a point where light starts interacting with thise gaps in a complicated way that make the plastic opaque and seemingly more white.