Engineering, 25.11.2021 05:30 ptrlvn01

A silicone polymer film of 4 mm thickness coats a flat, nonporous, inert surface. The polymer film is exposed to stagnant 100% O2 gas maintained at 1.5 atm. Oxygen gas is sparingly soluble in the silicone polymer film, with the solubility relationship given by Ca = S* Pa with S = 3:16 g mol O2/m3 silicone atm O2 at 298 K. Initially, there is 0.39 g mol O2/m3 uniformly dissolved in the film. The diffusion coefficient of O2 in silicone is 1 × 10-11 m2/s at 298 K. a. At a very short time of 10 s, O2 does not penetrate very far into the silicone polymer film. Under this physical situation, what is the flux of O2 into the surface of the silicone polymer film at this time? b. At a much longer time, the dissolved O2 concentration in the silicone polymer film at the polymer/inert interface is now 3.0 g mol/m3. How long will it take to achieve this concentration?

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A silicone polymer film of 4 mm thickness coats a flat, nonporous, inert surface. The polymer film i...