Difference between Hydrophobic and Hydrophilic Filters

Do you have these questions below when choosing filters?

What is the difference between hydrophobic and hydrophilic?

What are hydrophilic filters and hydrophobic filters suitable for?

Which filters are the hydrophilic filters?

Which filters are the hydrophobic filters?

Why are ptfe membranes both hydrophilic and hydrophobic?

More questions about choosing syringe filters, please check here

What is the difference between hydrophobic and hydrophilic?

Hydrophilic:

When the electrostatic gravitational force between the water molecules and the material is greater than the gravitational force between the water molecules themselves, the droplets will disperse.

Here, the instantaneous angle between the edge of the droplet and the surface (water contact angle) will be less than 90°.

This type of material is called hydrophilic, which literally means “water-loving”. The more hydrophilic the surface of the material, the smaller the water contact angle.

Hydrophobic：

When the electrostatic gravitational force between the water molecules and the material is less than the gravitational force between the water molecules themselves, the water droplets will pull themselves into a flattened spherical shape, with a water contact angle > 90°.

This type of material is called hydrophobic, which literally means “afraid of water”, but more accurately means “water repellent”. The more hydrophobic the surface of the material, the greater the water contact angle.

What are hydrophilic filters and hydrophobic filters suitable for?

Hydrophobic membrane filters are ideal for air and gas filtration, but not for filtering aqueous solutions, more commonly used in oil and gas applications.

Hydrophilic membrane filters are typically used to clarify and disinfect water-based fluids, but are not typically used for venting applications.

Which filters are the hydrophilic filters?

Hydrophilic filters: PES, CA, MCE, NYLON, PTFE

Which filters are the hydrophobic filters?

Hydrophobic filters: PVDF, PTFE

Why are ptfe membranes both hydrophilic and hydrophobic?

Hydrophilic PTFE filter membranes are modified from hydrophobic PTFE filter membranes, which have extremely good chemical compatibility and can withstand almost all solvents.

It is suitable for applications such as organic solvent filtration, mixed solvents, acid or alkaline liquids, filtration of strong oxidizing solutions, etc. for sterilization filtration applications.

Find the most suitable syringe filter for your analysis at Aijiren.