Multifunctional adhesives by integration of carbon nanotubes

This paper describes the investigations of different functionalised and non functionalised types of Carbon Nanotubes (CNTs) in an epoxy resin. Inserting nanoparticles into adhesives improved the mechanical and electrical properties of the material. The chosen method led to excellent degrees of dispersion resulting in a significant increase in electrical conductivity already at quite low CNT contents. Measuring electrical conductivity resulted in the electrical percolation starting at 0.01 wt%. With further increase of CNT content at about 0.3 wt%, the conductivity drastically increases into the conductive range. Through this we demonstrated that filling adhesives with Multi walled Carbon Nanotubes (MWNT) improves the electrical properties of adhesives. To further investigate the dependence of the conductivity to temperature and humidity, aging tests were carried out. The results reflect an independence of the conductivity to temperature and humidity. A significant enhancement of the mechanical properties of the composites could be shown. Adhesion tests were conducted for the characterisation of the adhesion and cohesion between adhesive and adherend. Investigations of the shear strength resulted in an improvement of bonded joints with increasing filler concentration.