In a four-year research project Ensis - the CSIRO’s entity for forestry, wood and paper research and technology - is collaborating with Monash University to assess the long-term durability in the Australian environment of engineered wood products such as glulam manufactured with a new generation of adhesives.
Under the current Australian Standard, manufacturers are restricted to using resorinol formaldehyde and phenol resorcinol formaldehyde adhesives in glulam engineered wood products for external structural applications. Potentially attractive alternatives, isocyanate -based adhesives (IBAs), have recently been approved in parts of Europe. The project’s findings will help determine whether they will be allowed here.
Glulam has rapidly gained popularity for a wide range of uses - from major structural components of buildings to furniture. A number of Australian manufacturers produce it.
Advantages claimed for IBAs over currently used adhesives include reduced costs because smaller quantities are needed, easier handling and a better-looking product because glue is transparent. In addition there is no possibility of formaldehyde emissions, a potentially significant occupational health benefit.
Key questions to be addressed in the project include how well the new adhesives bond Australian timbers and their long-term durability under extremes of hot and cold, drought and high rainfall.
On the basis of the findings the researchers hope to design a rapid test for long-term durability. The results will have application to the use of IBAs in other engineered wood products such as laminated veneer lumber and plywood.
Source : Building Product News