Curing of epoxy resins with nanoparticles

Solid, transparent epoxy-based nanocomposites with organophilic layered silicates as polymerisation initiators were produced for the first time. The powder formation which up until now has taken place during the self-polymerisation reaction was prevented using non-ionic dispersing agents and optimization of the silicate structure. This allows these curing systems to be used for bonding applications. In particular, the imperfect structure of the organophilic layered silicates not only leads to excellent stability of the monomer dispersion but also gives rise to considerably greater delaminarion in many polymers. In bonding tests, the silicate-based initiator systems with the cycloaliphatic epoxide showed similar lap shear strengths to bonds produced using classical initiator systems. In order to optimise the layer silicate hardener systems, the initiator reactivity was increased by varying the cations. In further work the mechanical properties of the resulting nanocompos ites will be tested and the impact resistance will be improved by additives. A primary goal is to transfer the knowledge that has been gained to other epoxide systems, because the thermally controlled release of an initiator from a layered silicate is a highly promising way of producing reactive mixtures which are very stable for storage, even for very reactive systems.