The ability to monitor and understand the structural and component health and usage parameters of critical infrastructure for both safety and efficiency is increasingly becoming a priority for industry, defence and national infrastructure. Electroactive polymer thin films are capable of sensing nanoscale strains on both conventional and new light weight structural materials. They also have the potential for incorporation within new structural materials themselves such as carbon fibre composites allowing these new materials to be monitored and strain mapped continuously over their lifetime. Integrated, rapid and high sensitivity sensing provides the data for algorithms to progress from diagnostic maintenance determining the state at a point in time to the predictive prognostic structural health management of significant assets.
A range of organic materials and composites polymers provide electron mobilities suitable for various thin film devices. Polyimide – carbon nanoparticle composites provide superior thermal stability while maintaining mechanical strength, dimensional stability and low dissipation factors for high endurance applications in industrial and defence infrastructure. Yet polyimides used in electronic devices often demonstrate poor adhesion as well as thermal and stiffness mismatches that generate high interfacial stresses which result in displacements, cracks and delaminations.
While there are extensive studies on pure polyimide surfaces, there appears no detailed studies on polyimide nanocomposite adhesion onto surfaces employed in electronic devices. Here, we investigate aspects of the interfacial chemistry and relate them to the surface microstructure and adhesional characteristics on two advanced substrates aluminium alloys and carbon fibre composites used the aerospace industries.