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DOE OSTI · 1188930

Measuring time-dependent diffusion in polymer matrix composites

Pilli, Siva Prasad·Smith, Lloyd V.·Shutthanandan, V.
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Abstract

Moisture plays a significant role in influencing the mechanical behavior and long-term durability of polymer matrix composites (PMC’s). The common methods used to determine the moisture diffusion coefficients of PMCs are based on the solution of Fickian diffusion in the one-dimensional domain. Fick’s Law assumes that equilibrium between the material surface and the external vapor is established instantaneously. A time dependent boundary condition has been shown to improve correlation with some bulk diffusion measurements, but has not been validated experimentally. The surface moisture content in a Toray 800S/3900-2B toughened quasi-isotropic laminate system, [0/±60]s, was analyzed experimentally using Nuclear Reaction Analysis (NRA). It was found that the surface moisture content showed a rapid increase to an intermediate concentration C0, followed by a slow linear increase to the saturation level.

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compositesdiffusionEnvironmental Molecular Sciences Laboratorynon-fickian

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Pilli, Siva Prasad, Smith, Lloyd V., Shutthanandan, V.. 2014-11-01. Measuring time-dependent diffusion in polymer matrix composites. https://doi.org/10.1007/s11043-012-9175-z

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