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. A large series of contact resistance and friction coefficient measurements have been performed in a sphere/plane situation to characterize each type of polyacrylonitrile (PAN) derivative in conditions quite near real ones. The results bring out very promising performances for some of the obtained materials