Why is my PDMS layer giving a low air permeability?

10 October 2018 0 2K Report

Hello,

I am using Sylgard 184 crosslinked PDMS for composite membranes to test for air permeability. when I thermally crosslink it to test the permeability I get a value that is 50x less than what is quoted in publications. I follow the same procedure, mixing 10:1 ratio, degassing, spin coating and then thermally annealing at 65 degrees for 3 hrs. Any help is appreciated.

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