Asked by: Sharon Philippidis, by email
Polystyrene is the material of choice for packaging because it's nice and light. It's easy to snap in half or crumble but, crucially, it's strong in compression and therefore protects delicate objects if dropped or crushed. Polystyrene is also a very good insulator, meaning that it quickly accrues electrical charge. This gives it a strong electrostatic attraction to other objects, causing it to readily stick to things.
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