All about Polyurethane (often called PU)
What is polyurethane foam?
A polyurethane, commonly abbreviated as PU, is any polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by reacting a monomer containing at least two isocyanate functional groups with another monomer containing at least two alcohol groups in the presence of a catalyst. Polyurethane products are often called "urethanes". Flexible polyurethane formulations cover an extremely wide range of hardness, densities, and cell structures.
What is polyurethane foam used for?
The major markets for flexible polyurethane are as cushioning materials in furniture, bedding, carpet underlay, automotive and packaging applications. Flexible polyurethane foams can be molded to shape or produced in large bunstock form for later cutting and fabrication.
How is Polyurethane Foam PU Made?
Basically there are 2 reactions in the formation of flexible polyurethane foam. The first is the polymerization reaction between an isocyante and an alcohol. The second reaction is where the polyurethane polymer must be expanded by the introduction of bubbles and a gas. Its during these reactions that heat and gases are given off.
Flexible Polyurethane Foam Odour
Odour is a common problem in the final production of flexible polyurethane foam. Today the polyurethane industry is looking at reducing odour emissions by using alternative chemicals and looking at different manufacturing practises in order to keep residual odour to a minimal.