Investigating the possibility of applying the “click” reactions to enable high yielding, reactivity in ambient conditions and fast reaction kinetics.

IASS focuses on the formulation, preparation and characterisation of self-healing thermosetting composites containing dispersed nanoscale fillers. This project will specifically target composites tailored for multifunctional applications such as lighting strike protection, impact damage and flame resistance, something that restricts the current performance of composites. These composites will find primary use in the aerospace arena.

The increased interest in multifunctional materials and structures is driven by the need for development of new materials and structures that simultaneously perform multiple structural functions, combined non-structural and structural functions, or both. Up to now, the traditional approach to the development of structures is to address the load-carrying function and other functional requirements separately, resulting in a suboptimal load-bearing structure with add-on attachments which perform the non-structural functions with the penalty of added weight. Recently, however, there has been increased interest in the development of load-bearing materials and structures which have integral non-load-bearing functions, guided by recent discoveries about Nanofillers and nanotechnology that can help to project materials working as multifunctional systems. The multifunctional composite will be developed in such way to impart specific abilities and functions to increase electrical conductivity, damage and flame resistance.

At present, technology consists of aircraft’s skins made primarily of aluminium, which is a very good conductor of electricity. By making sure that there are no gaps in this conductive path, the engineer can assure that most of the lightning current will remain on the exterior skin of the aircraft. However, this solution adds an additional weight to the aircraft and reduces composite advantage. On the other hand, IASS aims to try the use of conductive nanofiller into polymeric matrix in order to enhance mechanical and electrical properties and improve additional properties such as flame retardant behaviour and tailored EM properties. At this stage it should be emphasised that the choice of the nanofiller is critical and should meet all the requested requirements.

Currently, most industrial materials rely entirely on passive protection mechanisms. The problem occurs to the fact that they will always stay passive, and therefore their lifetime and functionality is limited and related to the amount of protective additives and the intensity of the consumption. IASS detect the need for developing better, and preferentially active, process for the protection/repair of damaged materials – self-repairing processes.  The project has introduced 4 approaches, to achieve this goal, so as to explore alternative concepts and reduce the risks of failure for the self-healing functionality in multifunctional materials.

Finally, in aircraft manufacture, flame retardant plastics are used in the production of cabin walls, overhead bins, galleys and lavatories among other interior parts. Regulations require that many of these plastics be self-extinguishing and flame retardant but they do not indicate the additives that can be used. From now on, aircraft manufacturers will be required to demonstrate that polymer structural composites provide high or equivalent safety with respect to the traditional material system (aluminium alloy). For this reason the development of efficient strategies to overcome this critical point is strongly desired, so IASS proposes three different approaches to provide fire-resistant structural compounds.

To sum up, the overall objective of the project is to combine the above functionalities through the following:

  • The use of functionalised nanofiller as conductive network and catalyst support to host a self-healing catalyst
  • Implementation of new catalytic pathways and concepts for catalysis, in particular in the field of the “click” – reactions and ROMP-based processes 
  • Investigation on the possibility to apply the “click” reactions to enable high yielding, reactivity in ambient conditions and fast reaction kinetics.