Oxygen permeability released carbon dioxide

For food packages, polymeric materials should exhibit an adequate carbon dioxide oxygen ratio (generally lower than 7). The process of permeation involves dissolution of the gas in one side of the membrane, diffusion of the gas through it and release of the gas from the other side of the membrane. A conventional method for determining permeability and diffusion coefficients in polymers involves the measurement of membrane weight gain versus time until the final mass equilibrium mass is reached. 

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