Foams are mainly used as cushioning material in furniture, bedding, and
transportation. They are normally produced by a mixture of toluene diisocyanide
(TDI) and polyether polyols.

 

Rigid foams find application as insulation material in
refrigeration and construction. They are formed by reaction of mostly methylene
diphenyl diisocyanate (MDI) with an aromatic polyester polyol.

 

The fluorocarbons, the heavily criticized foam-blowing agents, have been substituted in industrialized
nations by less harmful substances in accordance with the 1989 Montreal Protocol
of the United Nations Environmental Program.

Foams are produced during the reaction of the liquid components and shaped by
extrusion or injection under heat or at room temperature. The exact formulation is
adjusted according to the processes. Polyurethane (PUR) components are delivered
in a standardized premixed form, a machine-ready system. However, systems have
to be designed for specific applications and the machinery used by the customers. In
most cases the best way of production has to be established in an experimental phase
on the customer’s production site. The assistance of the supplier’s technical staff is
often necessary because the specific production situation—retention times of the
liquids in the machines, tubes, and mixing equipment—cannot be easily simulated in
the laboratory. As the polyurethanes are quite reactive, the process kinetics depend
on the given chemical and physical parameters, and the industrial process needs to
be designed according to situation. A profound knowledge of the process technology
is absolutely necessary for the sales team. Successful marketing of polyurethanes
needs a technically oriented team with a high degree of practical experience; a
compilation of case studies is an important marketing asset.

Companies which integrate all PUR components (diisocanates, polyols, and
propylene oxides) have an advantage not only in price but also in the increased
possibility of modifying the components according to the customer’s needs. A
strongly integrated company in the PUR business is Bayer, supplying about a
quarter of the world demand in MDI and TDI.