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+ Polymer science
+ Molecules
+ Chemistry
+ Polymer physics
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Leon Baradat

Why are some polymers brittle, and what determines the brittleness of polymer materials?

Nobaudie Uno  Follow

Cross linking = brittle. Imagine a plastic milk bottle. It’s very flexible when new.

Leave it outside in the sun for a couple of months. It shatters instead of flexing.

The new plastic has strands of polymer that slide past each other. The old plastic is crosslinked and can’t flex.

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Andrew T  Follow

Brittleness is usually related to crystallinity. The higher the level of crystallinity, the more brittle it is. We try to control crystallinity with controlled cooling during processing, especially during molding processing. This pertains to injection molding and blow molding as well as rotational molding.

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