Polyurethane as industrial material
Polyurethane or PUR are plastics that can be used as material in many industries. Polyurethanes are mainly used in the form of foam from which elements of upholstery, coatings, heat insulation, packaging material and individual parts or components for housings are manufactured.
Cold soft foams and integral soft foams, integral rigid foams, compact duromers and moulding systems are available for the different industrial purposes. With regard to special applications, such as, for example, the enforcement of the part’s architecture, mould-in elements of plastic fibre, chipboard, steel or aluminium may be integrated.
Furthermore, coatings and adhesives may be produced from polyurethane, which are also used as thermoplastic materials.
From the chemical point of view, polyurethanes result from a poly addition reaction of isocyanate and polyol (as well as from other additives, if required). The reaction components are mixed in different processes with and without pressure.
This is either done in a high-pressure process using pressures up to 250 bar. The chemical reaction is optimised so that the cycle times are as short as possible.
The low-pressure process uses pressures up to 40 bar for mixing.
The longer reaction time of the components takes effect on the further processing.