Chemistry
How Polymers Degrade Through Photolysis and Hydrolysis in Environmental Conditions
Quick fact
Photolysis can break polymer bonds with UV light, but its efficiency is low for many common plastics because they don't absorb UV well; instead, impurities often trigger the reaction. Hydrolysis, on the other hand, is a key driver for polyester degradation, but it is extremely slow for polyolefins like polyethylene, making them persist for centuries in the environment.
Why this is interesting
You've seen plastic bottles and bags that seem to last forever, yet some plastics crumble after a few months outdoors. What makes the difference?