AMSTERDAM, NETHERLANDS — Producers of rigid polyurethane foam can expect continued growth from the construction industry.
That was the message of Reinhard Kaufung, sales manager for construction products for Bayer AG's polyurethanes business group, who spoke at the Polyurethanes World Congress, held Sept. 29-Oct. 1 in Amsterdam.
``The worldwide consumption of polyurethane rigid foam for construction has shown tremendous and steady growth over the last few decades and hit the [2.2 billion-pound] mark in 1996,'' Kaufung said.
World demand for PU raw materials, like methylene diphenyl diisocyanate, has been growing at a rate of about 7 percent per year.
``Therefore, securing material supply today requires virtually a new world-scale MDI plant every year,'' he said.
Still, PU foam represents just 7.4 percent of the insulating material used in Western Europe, Kaufung said. He cited the high initial cost of PU foams, compared to other insulating materials, as a factor limiting market share.
``We have to question whether it is always necessary to be the best at higher cost or price,'' he said.
Kaufung suggested producing low density, open-cell PU board as a direct competitor to fiberglass and mineral wool, in both cost and performance. The premium price and performance of the current high density, closed-cell foams still would find a market in high-end construction.
No matter what the form of the foam, a major challenge the rigid PU foam industry faces is the choice of blowing agents used.
``Since 1986, the main development efforts of the polyurethane industry in rigid foam around the world have been concentrating on the replacement of CFC-11,'' Kaufung said.
While chlorofluorocarbon-11 radically increased the insulation value of PU foam, it also was blamed for depleting the Earth's ozone layer. Hydrochlorofluorocarbons and hydrocarbons have replaced most CFC-11 applications, but HCFCs also destroy ozone and are scheduled to be replaced themselves. But the form of those replacements is still up in the air, Kaufung said.
If the final toxicity results are satisfactory, the favorite one, hydrofluorocarbon-245fa, probably will be commercially available in the next three years, he said. Meanwhile, ``pentane technology is spreading,'' especially in Europe, Kaufung said.
Another set of challenges facing rigid PU foam insulation is potential new fire codes in Europe.
``Polyurethane rigid foam complies with all fire safety standards. Probably higher flame-retarded foams will be required, and legislation will increasingly call for halogen-free foams,'' he said, adding that the development of flame retardants designed to meet these future requirements is already underway.
