Fuel Permeation Analysis Method Correlation

Due to recent considerations within the automotive industry and impending tougher restrictions on emission levels, an accelerated, accurate, repeatable method for determining fuel permeation through polymers is desired. This paper describes the results of a correlation study between the standard gravimetric method, in which the weight loss of the permeant through the film is recorded, and two types of new chromatographic techniques utilizing a flow-through system and a flame ionization detector (FID). The first chromatographic method enables separation of the fuel components by utilizing a capillary column in order to determine the individual permeation rates, while the second provides permeation data on the basis of the entire mixture. Additionally, since previous gravimetric analyses showed some scatter in the data, a new gravimetric cup was designed for the study. Three materials were evaluated for CM15 permeation at 40C using all three methods described above.