Gluing without glue

Trends of the adhesives Industry

form 221
July/August 2008


publisher

Birkhäuser (Basel)

Adhesives can do a lot more today than just stick two things together. They can be flame-resistant, electrically conductive – or even completely dispensable. At the moment textiles which adhere to almost any surface are the talk of the town.

It is not a complete coincidence that the adhesive textiles which Création Baumann has launched on the market bear the name Gecko: A specially structured silicone coating provides the respective adhesion and the material can be applied and removed a number of times without leaving traces. All you need in such a case is a pore-free surface. This could be glass but also metal or plastic. Gecko can be used, for example, where visual and glare protection are required but where the architectural situation does not allow for curtains, blinds or panels. The materials have been tested in particular on unstructured float-glass, on glass facades and dividing walls.

Surprising new research findings are also to be seen in the field of real adhesive substances. At the University of Applied Sciences in Kiel researchers are currently working on an electricity conducting adhesive which could replace soft-soldering. Nano-dimensioned silver particles mixed into the mass enable not only excellent electric conductivity but also a high degree of form-stability when temperatures fluctuate widely. The silver adhesive is highly resistant to mechanical stress and retains its conductivity even in extreme conditions.

Scientists at the Fraunhofer IFAM in Bremen and at SusTech in Darmstadt are busy with another problem: Up until now industrial adhesives have had the disadvantage that unlike normal household or model-building adhesives they only hardened once heat was applied. This meant that an oven or hot air stream was required, the hardening process takes time, and the applied heat puts stress on the other structural components in the vicinity of the adhesive. Scientists are now developing an adhesive which contains magnetic nano-particles to alleviate this problem. These warm themselves in a magnetic field and accelerate the adhesion process. Energy requirements are thus lower, and thanks to the low heat stress particularly heat-sensitive components can also be fused – which should make the innovative adhesive suitable for light construction.

3M now offers another alternative for components which are sensitive to high temperatures: The adhesive system 5958FR is an adhesive band made of acrylic foam. Due to its flame resistant properties it can replace screws, weld-seams or rivets where strict fire prevention regulations have thus far not permitted glued connections. The adhesive band offers not just the automotive industry but also architects new possibilities for planning insulation, fire-protection windows and internal dividing walls or elevators.

www.fh-kiel.de
www.ifam.fraunhofer.de
www.3m.com
www.creationbaumann.de

image source: Creation Baumann