Which of these types of plastics are safe to use in a weighted blanket?

Polypropylene is used in thermal underwear. The catch is that it has a low melting point, so you have to be careful about temp during tumble drying.

I don’t know the answer, but i would be worried about outgassing – It refers to the release of gas trapped within a solid, such as a high-frequency circuit-board material. Some plastics outgas themselves.

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I doubt you could wash or dry a weighted blanket in conventional machines. Those blankets are just too heavy, and especially for tumble drying.

@RocketGuy Plastic underwear! Now I’m just imagining melted underwear stuck to a dryer. Haha

@elbanditoroso Very important thing to consider when working with plastics. Though they actually use polyethylene to make encasements(?) for crib mattresses to protect babies from offgassing from the mattress. That said, it still totally stunk up my car. Going to let it air out before making a blanket!

@snowberry Depends on the size of the blanket and how sturdy it is. But totally doable if it’s small and sturdy. Just low heat so you don’t melt it like plastic underwear!