Modelling a semi-permeable membrane

[Oliverben5672]

Hi, I want to run an experiment and to do so I need to create something that will function as a semi-permeable membrane. It must let water through but not oil. I’ve looked about a lot but all options seem excessively expensive. If anyone knows a cheap option, or a way to build something that would work it would be much appreciated. Thanks

[jimmydasaint]

Are the prices on this site too expensive?

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