A plastic preform, container or article includes a multilayer wall having at least one layer of a matrix resin, at least one layer of a barrier resin, an adhesion-promoting material blended with the barrier resin and/or matrix resin, and an active oxygen barrier composition blended with the barrier resin and/or matrix resin. The adhesion-promoting material promotes bonding between the barrier and matrix resin layers and includes an amine polymer, preferably an imine polymer having a number of available primary, secondary or tertiary amine groups. The matrix resin preferably is an ester-containing resin, such as PET. The barrier resin preferably is EVOH. The active oxygen barrier composition includes a metal with an additive compound, and may also include a host polymer.