As we all know that due to surface tension, the hydrophobic membrane(Hydrophobic PTFE filter membrane )is relatively repulsive to water, and it is difficult for water to pass through. Hydrophilic means that water is easily filtered out. Here are more introduces about the differences: Hydrophilic vs. Hydrophobic Membrane Filters.
Hydrophilic vs. Hydrophobic Membrane Filters:
Difference definition between hydrophilic and hydrophobic filter membranes:
- Hydrophilic, (hydrophilic PTFE filter membrane) is the characteristic of having an affinity for water.
- Such as chromium, aluminum, zinc, and other metal plates and their hydroxides and substances with capillary phenomenon have good hydrophilic effects.
- Hydrophobic,(hydrophobic PTFE filter membrane ) is the property of repelling water.
- For example, the lipophilic components of printing plate graphics and printing inks have good hydrophobicity. The hydrophobicity of the alkyl and benzene rings in organic matter means that they make the organic matter insoluble in water.
Difference usages between hydrophilic and hydrophobic filter membranes:
Hydrophilic vs. Hydrophobic Membrane Filters:
1. Hydrophilic membrane filter use:
- When a hydrophilic membrane filter is in contact with water, surface tension-related capillary action causes water to spontaneously enter and fill the pores.
- In this way, the membrane is easily wetted and allows a large amount of water to flow through the pores.
- Once wetted, hydrophilic membranes will not allow the substantial flow of air or other gases unless they are applied at pressures greater than the bubble point of the membrane.
- Hydrophilic filters are commonly used with water and aqueous solutions. Hydrophilic membranes are generally not used for air, gas, or exhaust filtration because flow can be blocked if the filter is accidentally wetted (for example, by condensation).
2. Hydrophobic membrane filter use:
- When the hydrophobic membrane filter is in contact with water, surface tension drives the water out of the pores.
- Unless the applied water pressure is greater than the inlet pressure of the membrane, water will not enter the pores and the membrane will act as a barrier to water flow.
- Liquids with low surface tension, such as alcohol, spontaneously enter and fill the pores of the hydrophobic membrane.
- Once all the air in the hole has been displaced and there is no longer any surface tension, water can easily enter the hole, displace low surface tension
- Fluid and pass through the membrane. The membrane then allows a lot of water to flow as long as the pores remain filled with water.
- Hydrophobic filters are typically used with compatible non-aqueous fluids. They are also commonly used as air, gas, or ventilation filters.
- Hydrophobic membrane filters are sometimes used with water or aqueous solutions; and, in these applications, they must be pre-wetted with low surface tension, and water-miscible liquid prior to use.
Difference between hydrophilic PTFE membrane and hydrophobic PTFE membrane:
Hydrophilic vs hydrophobic PTFE membrane:
- The conventional hydrophobic polytetrafluoroethylene membrane is modified to obtain a hydrophilic polytetrafluoroethylene membrane, which can be used for the filtration of aqueous solutions. Hydrophobic PTFE is inherently hydrophobic.
- After modification, the aqueous solution and organic solution can be filtered, which is more convenient. Chemical resistance is also good.
- When we buy, we generally need PTFE filter membranes, because sometimes we need to filter organic solvents, and sometimes we need to filter aqueous solutions
- And the merchants do not specifically ask about the difference between hydrophilicity and hydrophobicity.
- At present, there are still relatively few hydrophilic PTFE, so in general, if customers want PTFE, the default is hydrophobic PTFE.
