Correlation of content and corrosion protection of volatile corrosion inhibitors in packaging material - regaining trust in VCI

Two representative types of commercial volatile corrosion inhibitor (VCI) packaging materials without a potential for health hazards according to TRGS 615 were investigated: a paper containing ethanol amine and a polyethylene foil containing sodium nitrite as main VCI ingredients. For a variation of VCI concentration the packaging material was thermally treated at 60-100 degrees C and the amount of VCI remaining was determined after this accelerated desorption. Additionally a nitrite-free polyethylene foil was impregnated with various amounts of sodium nitrite. Correlations of VCI content - of both the amine and nitrite - with corrosion protection of mild steel were observed. For ethanol amine a color change reaction is proposed to indicate the remaining potential of corrosion protection. This work is aimed at regaining trust in VCI technology.