What is the difference between open cell foam and memory foam?

Answer 1

I think memory foam is an example of a particular kind of open cell foam. Closed cell foams gain compression resistance by squeezing trapped air pockets in their closed bubbles. Open cell foams let the internal air squeeze out as they are compressed because their bubbles have small holes in their walls, so their compression resistance relies strictly on the elasticity of the elasticity of their cell wall material.

Memory foam is made with a material that is highly elastic and springs back to almost its original shape when the compression forces are released. They are good springs. The return to original shape is slowed mostly by the air having to find its way back into the expanding but vented cells.

Non memory foam retains its deformation to a much higher degree after it is deformed. It is a poor spring.

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Regards,

John Popelish

Answer 2

Open cell foam is less dense. Memory foam has less air pockets and is more compact, more dense.