Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) and microimaging experiments have been performed to study the diffusion of liquid alkanes into a variety of semicrystalline polyethylene (PE) samples. The results highlight the importance of the crystalline phase in controlling the diffusion process in terms of both the geometric impedance imposed by the presence of impenetrable crystals and their effect on the mobility of the polymer chains comprising the amorphous material through which the penetrants migrate.
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