▎ 摘　　要

Time-dependent electrochemical properties of graphene nanoplatelets (GP) and self-crosslinked polyvinyl butyral (PVB) composites are discussed. Electrochemical experiments in chloride medium revealed that GP offers short-term excellent protection from the physico-chemical mechanisms operating within the barrier. For longer periods of time, corrosion promotion was discovered due to induced porosity and electrochemical mechanisms related to excellent electrical conductivity and higher position in the galvanic series. This research has helped to understand the misleading anti-corrosion properties associated with graphene-polymer composite coatings.