Elaboration of heat-treated thin films of polyacrylonitrile for connector application

An original alternative to the different terminal coatings classically used for the protection of low-level connectors is presented involving thin films of polymer treated in order to have adequate electrical and tribological properties. The authors show that polyacrylonitrile layers a few hundred Angstroms thick, grafted on electroplated nickel and rapidly heated in a lamp furnace, lead to organic coatings well suited for the aimed application. The evolution of the molecular structure of the polymer has been investigated by IRRAS and XPS techniques. Large series of contact resistance and friction coefficient measurements have been performed in a sphere/plane situation to characterize each type of PAN derivative in conditions quite near from real ones. Results bring out very promising performances for some of the obtained materials.