Electrically conductive adhesives with a focus on adhesives that contain carbon nanotubes

On the basis of an analysis of results presented in the literature, the currently existing knowledge about relationships between the microstructural and physical properties of hard coatings is discussed. Particular emphasis is placed on the role of microstructural features, such as grain boundaries, nonequilibrium structures, impurities, and texture, in controlling the film hardness. On the basis of an analysis of results presented in the literature, the currently existing knowledge of electrically conductive adhesives (ECAs) is discussed. Particular focus is placed on the results obtained with ECAs that contain carbon nanotubes (CNTs) as conductive fillers. The review is divided in curable ECAs based on epoxy resins, and noncurable conductive hot melts and pressure-sensitive adhesives based on thermoplastic polymers. More literature results were found for epoxy/conductive filler ECAs than for other adhesives. Confirming the assessments made in a book by Li et al., which refers to nanotechnologies in ECAs, we found that only a reduced number of articles allude to polymer/CNT ECAs. Our analysis of the results includes a study of the balance between the viscosity, immediate adhesion, solidification process, electrical conductivity, and mechanical properties of the adhesives. (c) 2013 Wiley Periodicals, Inc.