Membrane materials with uniform pore size.

[dcfg]

What materials are available with a very tight pore size distribution in the range 0.1 to 10 micron. I am looking for both hydrophillic and hydrophobic materials. These do not necessarily have to be commercially available materials.

 

[Silverbullet]

I do not know the pore size but I do know that silicone is porous to moisture. I have a problem trying to treat my silicone mouldings with a hydrophobic/hydrophillic coating to reduce water absorbtion.

 

[Jigneshpadia2002]

you can get hydrophilic membrane with any pore size commercially available from Millipore. Material of Construction (MOC) is PVDF

Hydrophobic membrane again any pore size MOC is PTFE.

Hope this helps !

 

[aspearin1]

Most sterilizing grades of membrane filter cartridges have a tighter pore distribution about 0.2 microns. These filters are efficient at removing all colony forming units (CFU)of B. diminuta, the smallest known bacteria. These membranes increase their effectiveness by using multiple redundant layers in a pleated matrix. To maintain this efficiency and be grade as "sterilizing" a 0.2 micron filter should not have a 10 micron pore. The distribution should be much tighter. Materials available: Nylon (hydrophilic), Polyethersulfone-PES (Hydrophobic or hydrophilized). The others listed above as well. Millipore also has some polyethylene and polypropylene membranes. There are also meltblown (hydrophobic) media and cellulosic (hydrophylic) membranes you may wish to consider. If talking to a rep, you may be able to get an indication on pore distribution if you request data on Bubble Point. There is an initial bubble point (IBP) which corresponds to the largest pore. Then there is the foam all over point (FAOP) which corresponds to the averave pore size. (FAOP and IBP are pressure readings). Other testing such as forward flow/water intrusion, air flow are also used.

FYI: pore sizes are not measured directly. They are correlated based on retention of contaminants of a known size and distribution.

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee

 

[hprorelis]

Pore size is managed by sittering temperature (about 1200 °C) during ceramic membrane production

Pore size is managed by phase inversion process during organic membrane production - Polymer concentration in the collodion used for membrane production determines pore size.