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High-performance gluing - Certified PUR adhesives for load-bearing glulam

timber load bearing glulam

Load-bearing timber elements made from glulam. Image source: Jowat SE

Adhesives used in the manufacture of load-bearing timber parts must be certified and meet special requirements. The product family Jowapur® 681.xx supplied by the adhesives manufacturer Jowat provides an extensive portfolio of certified and tried and trusted adhesives, with different products for a wide range of manufacturing processes in the field of load-bearing glulam.

The importance of load-bearing glulam in construction has been growing constantly over the years. Its use in new buildings is increasing and structures based on load-bearing glulam have become bigger and more sophisticated. At the same time, it provides possibilities for architectural creativity and aesthetics that are often unmatched. The adhesives specialist Jowat from Detmold is supporting this sustainable trend with an expertise based on many years of experience, with optimum service and with certified high-performance adhesives.

One family for all cases
The one-component PUR prepolymer adhesives of the Jowapur® 681.xx product family are certified according to EN 15425:2017 and are tailor-made to optimally meet the requirements for load-bearing glulam. They can be used in fingerjointing as well as in CLT/laminating applications, provide a choice of assembly times between 10 and 60 minutes, and facilitate an assembly time-pressing time ratio of up to 1:1. Industrial processors can therefore choose the adhesive that best fits their parameters to optimise their specific process and to either increase capacity or improve process reliability by only changing the adhesive and without the need for major investments.

PUR – Full of benefits
Compared to other technologies, PUR prepolymer adhesives for the manufacture of load-bearing timber parts provide several advantages in the manufacturing process as well as for the end product. They do not contain any formaldehyde or solvents, are free of emissions and completely odourless when fully cured, and require considerably lower application amounts due to a solids content of 100 %. Depending on the formulation, these adhesives can cure in a short period of time at room temperature already and facilitate almost invisible gluelines due to their colourless appearance. In addition, Jowapur® adhesives are processed as single components. Therefore, no mixing is necessary, pot lives become obsolete, and remnants from production are prevented.
A major secret behind the superior performance of the Jowapur® 681.xx product family are specially developed reinforcement fibres which are added to the adhesive in a specific procedure. Those fibres increase the strength of the glueline and help prevent the joined parts from sliding apart during production and curing. In addition, they lower the amount og foaming during the curing process and thereby considerably reduce the soiling of machines and equipment and help prevent the sticking together of parts that have been stacked or stored next to each other. The improved spread characteristics of these adhesives makes them an optimal choice for contactless applicator systems in fingerjointing units.

Sustainable construction
Jowat is confident that the importance of load-bearing glulam in construction will only continue to increase in coming years – partly due to global sustainability strategies. That development is to be supported with optimised high-performance adhesives. “Building with wood brings only benefits,” underscores Ralph Kirst from Business Development Load-bearing Glulam at Jowat SE. “And adhesive bonding is a future-oriented joining method that minimises construction costs and time in timber construction. Entire buildings can be prefabricated industrially and assembled on site.” Wood as a building material is therefore expected to continue on its upward trajectory. Apart from the economic benefits it provides, the material is also an ideal choice from an environmental point of view. Wood is a sustainable CO2 sink and thus actively supports the fight against global warming.
 

The article is published in the magazine ''Holzkurier 35/2020" in German language. You can download the original article down below.