What are the numbers for permeation rates before and after fluorination?
A. Data does exist for weight loss of pure solvents in fluorinated containers and for many there is a substantial reduction of product loss achieved by fluorination. However, FSI does not advise utilizing this data for package engineering. Most product formulations are a complex mixture of ingredients. Some ingredients may permeate; some others may not. A permeate may be important to efficacy, or may be an inert filler, extender or carrier. Permeation rates are significantly altered by the presence of an example from the auto industry is that permeation of petroleum fuel through plastic gasoline tanks is increased by the presence of alcohols in the fuel. Trace quantities of fuel injector cleaner in the fuel mix also impact actual fuel permeation rates. Thus, it is unreliable to use permeation data for single solvents to predict permeation of complex mixtures. The only valid approach is to perform tests with the actual formulation in each container application.(See also Samples, and Tes
