What is the Difference between Open-cell and Closed-cell Urethane Foams?
Open-cell foam is soft – like a cushion or the packaging material molded inside a plastic bag to fit a fragile object being shipped. The cell walls, or surfaces of the bubbles, are broken and air fills all of the spaces in the material. This makes the foam soft or weak, as if it were made of broken balloons or soft toy rubber balls. The insulation value of this foam is related to the insulation value of the calm air inside the matrix of broken cells. The densities of open-cell foams are around 1/2 to 3/4 of a pound per cubic foot. Closed-cell foam has varying degrees of hardness, depending on its density. A normal, closed-cell insulation or flotation urethane is between 2 and 3 pounds per cubic foot. It is strong enough to walk on without major distortion. Most of the cells or bubbles in the foam are not broken; they resemble inflated balloons or soccer balls, piled together in a compact configuration. This makes it strong or rigid because the bubbles are strong enough to take a lot of
