AbstractRecent experimental and theoretical work on the concentration‐dependent diffusion of solvents in polymers has led to a reasonably detailed understanding of the processes involved. The possibility exists of supplementing standard but costly surveillance testing with rapid laboratory‐scale measurements of plasticizer migration. Many solvent‐polymer systems conform rather closely to the assumption that the amount of material transferred by diffusion is a function of the composite variablet1/2/l. This means that any scale factor applied to the diffusion path length, in a one‐dimensional system, may be compensated for by applying the square of this factor to the time. It has been shown that this assumption can apply with reasonable accuracy to plasticizer diffusion in the propellant‐inhibitor systems. By approximating a particular 2 in. rocket charge with a one‐dimensional model, it is possible to predict the time required for the unit's inhibitor to reach specified levels of plasticizer migration at any storage temperature of interest. A large temperature coefficient appears to be associated with the equilibrium plasticizer migration in the system chosen for experiment, as well as with the rate. Unless suitable allowance is made, this can lead to serious misinterpretation of the results of the surveillance that has been accelerated by raising the storage
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