Oleophobic PTFE Membranes


Oleophobic membrane is a super-hydrophobic PTFE membrane modified by hydrophobicity surface treatment (molecular level). Cobetter Oleophobic PTFE membrane meets Oil Rating 8 (AATCC 118), staying hydrophobic against low surface tension liquids like lipids and ethyl alcohol/methyl alcohol.


Cobetter hydrophobic PTFE membrane is qualified for common venting cases, but for most of chemotherapeutic medicine infusion venting applications, to secure long duration of non-wetting status and maintain venting function, the vent membrane is required to have a lower surface tension than that of contacting liquids, and Oleophobic PTFE membrane is therefore introduced because of its super low surface tension. 

Oleophobic option is necessary for chemotherapeutic medicine delivery venting (Alcohol Repellent), and is also recommended for common venting applications because it offers a longer hydrophobic lifetime, a more secured non-leakage promise, and a higher product safety.

Surface Tension Comparison of Various Membranes and Solvents

   Material   Surface Tension (Dyn/cm, 20℃)
   Hydrophilic PES Membrane   >85
   5% NaCl   77.5
   Pure water   72.8
   Hydrophobic PTFE Membrane   31
   Chloroform   27.1
   Acetone   23.7
   Methyl Alcohol   22.6
   Ethyl Alcohol   22.3
   Oleophobic PTFE Membrane   19

                                                                                                            Note: 1Dyn/cm=1mN/m

Certified Biological Safety (ISO 10993/USP Class VI)

Excellent Air Permeability, Outstanding Air Flow Rates

Optimized Backing Material,Better Sealing Capability

Wide Range of Pore Size (0.02-10μm)

Stable Water Entry Pressure (WEP)


Compatible with Different Sealing Methods

Ultrasonic, Heat, RF Welding, Mechanical, Inserting Molding

Serilization Compatibility

Autoclave,Ethylene Oxide, E-Beam, Gamma Irradiation

Available Pore Sizes (μm)

0.02,  0.03,  0.05,  0.1,  0.2,  0.45,  0.8,  1.0,  2.0,  5.0,  10.0

Typical Performance Characteristics (*0.2μm)

Filtration Efficiency ≥99.99999% Brevundimonas diminuta
Air Flow Rates Gurley 17-49sec
WEP(60s) >450 KPa
Thickness 280-440μm (Supported)

Typical Applications

- IV Filter Vent
- Transducer Protector (TP)
- Bacterial Air Vent
- Sensor Protection Cover
- Package Vents
- Drip Chamber Spike Vent
- Dispensing Pin
- Urine Meters/Bags
- Ostomy Pouches

Support Type

Polyester, Polypropylene, Un-supported

Membrane Formats

Roll, Sheet, Disc, Adhesive Backing, Customization

For technical data sheet or application inquiry, you are more than welcome to contact our sales representative by sales@cobetterfilter.com or leave a message