|Polymer Nanocomposites - Additives, properties, applications, environmental aspects|
Various additives are added to plastics to either improve processability, change product properties or protect them against thermal, UV or light influences. In the case of a polymer nanocomposite, the additives have at least one dimension of less than 100 nm and can be found in the form of platelets, fibres or particles. They primarily serve to improve tensile strength, thermoformability, flame retardancy, optical and electrical properties, and the barrier properties of the plastic into which they are incorporated. Nanoadditives include layered silicates such as montmorillonite, carbon-based additives (e.g. carbon black, carbon nanotubes, graphene), nanoscale metal oxides (e.g. SiO2, TiO2, Al2O3), metals (e.g. nano-silver, -gold, -copper), or organic additives such as nanocellulose or lignin nanoparticles. In addition to reductions in resources and weight, nanoadditives also have the potential to replace harmful substances such as environmentally problematic halogenated flame retardants. Across the world, polymer nanocomposites are already being used in packaging materials, the automotive industry and transportation, aerospace and energy technology, as well as in sporting goods. However, company surveys in the Austrian automotive and electronics industries have shown that nanoadditives currently only play a marginal role in these sectors. The main reasons are problems with dispersibility, large-scale production, high costs, and uncertainty around their impact on humans and the environment. There are still considerable gaps in knowledge. More research needs to be conducted with regard to release, exposure and environmental behaviour.