# What is the chemical composition of a Rubbermaid Roughneck container and is it feasible for me to make my own molds?

I'm looking for more information on the composition of a Rubbermaid Roughneck container. The description says "Roughneck containers are made with a durable polyethylene material for a lifetime of durability and strength." The Wikipedia entry indicates that polyethylene is the most common type of plastic with chemical composition $\ce{(C2H4)_{n}H2}$. But if this is so how are these containers able to flex instead of break like other plastic containers as well as tolerate greater temperature changes? I have a project that requires a custom shaped material of similar attributes. How feasible would it be to make my own mold at home? The shape I want to mold is very simple: a very thin rectangle about 35 width and 23 length. Are the chemicals involved dangerous to work with?

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