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Motivation for studying diffusion in polymers

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Sorption Isotherm on PET at 25 C

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Solubility and diffusivity of gasses in rubber

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Permeability of gases in rubber

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Permeability of gasses in various polymers

1 Barrer = 10-11 (cm3 O2 ) cm cm-2 s-1 mmHg-1. or 1 Barrer = 10-10 (cm3 O2 ) cm cm-2 s-1 cmHg-1. Here 'cm3 O2' represents a molar quantity of oxygen rather than a true volume. It represents the quantity of oxygen that would take up one cubic centimeter at standard temperature and pressure, as calculated via the ideal gas law.The 'cm' represents the thickness of the material whose permeability is being evaluated, and cm-2 is the reciprocal of the surface area of that material.

1 Barrer = 846 millilitre . mm / (cm2 . day. bar(a))

1 Barrer = 3.348 x 10-19 kmol m / (m2 s Pa)

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