Polyurethane (PU) stands for an important group of products within the big family of polymers or plastics. PU is a generic name for a wide range of foam types.
The structure of PU foam consists of a network of dodecahedron cells which behave as micro-springs. The properties of PU depend on :
the chemical composition and thickness of the cell walls.
the volume-solid matter/air ratio.
the concentration of the cell membranes (air permeability/open cell structure).