AbstractThe transport properties of gases and vapors in high barrier polymers and copolymers containing nitrile functionalities are discussed. The permeation behavior of oxygen, nitrogen, carbon dioxide, and water vapor are given in detail. Polymers containing methacrylonitrile as well as acrylonitrile units are included:Relationships of structure to permeability are given, in the light of known parameters for other polymers. A discussion of the Permachor values of nitrile polymers is presented, and methods of predicting permeation are given. Some anomalous behavior of transport under certain conditions are also presented.