A scientist from German research organisation The Fraunhofer-Gesellschaft has developed a fire-resistant material based on a most unlikely fire-fighting substance: paper.
With the use of asbestos as fire insulation for load-bearing structures prohibited, construction firms are looking for economic alternative materials which possess similar properties but do not pose the same health risks as asbestos and other mineral fibers.
Wolfgang Christ is working on an alternative to sprayed asbestos, based on cheap cellulose recovered from waste paper.
It might seem strange to qualify wood derivatives and paper as a heat-resistant insulating material, given that they are more usually considered as combustibles. But, as Christ explains, it’s all a question of mixing the cellulose with the right proportions of mineral components.
‘There are a number of inoffensive boron compounds which melt in contact with fire, forming a protective coating around the fibers. The incombustible mixture sinters and becomes even more solid, without causing any significant loss of the material’s thermal insulation properties.’ By optional addition of graphite, a particular extinguishing effect can be achieved. Mixed with standard commercial binders, the material is easy to process. It adheres well – even in thick layers – and also protects the steel against corrosion.
Christ claims that there are no other products on the market at present which demonstrate properties that are as comparable to sprayed asbestos. But even the new product exists only as laboratory samples so far.
‘We are now looking for companies capable of manufacturing the material on an industrial scale,’ comments Hans-Karl von Engel of the Fraunhofer Patent Center for German Research PST, who is in charge of the new invention.