Microporous ePTFE on Polypropylene Substrate
PTFE/PP Composite Membrane
PTFE/PP composite membrane combines a microporous expanded PTFE layer with a polypropylene support substrate. The ePTFE membrane provides hydrophobic, chemically inert filtration and venting; the PP backing adds structural integrity and handling ease. We supply this membrane for protective venting, air and gas filtration, dust collection, and moisture barrier applications. It is not a traditional flange sealing material.
At a Glance
Temperature Range
-20 °C to +90 °C continuous (PP substrate-limited); short-term excursions to ~+130 °C
Thickness Range
0.15 mm to 0.5 mm
Available Forms
Colours
Brands We Stock
Technical Properties
Typical values across stocked grades. Specific grade data sheets available on request.
Physical Characteristics
Thermal Conductivity
Low. Primarily a barrier material rather than a thermal conductor.
Dielectric Strength
High, with both PTFE and PP acting as excellent electrical insulators
Chemical Resistance
Resistant To
- Non-oxidising acids (dilute HCl, H₂SO₄, H₃PO₄)
- Alkalis and bases
- Alcohols (room temperature)
- Most organic solvents (room temperature)
- Aqueous solutions, salts
- Fats and oils
Limited Resistance
- Aromatic hydrocarbons above 60 °C (xylene, toluene), where PP weakens
- Chlorinated solvents above 60 °C (trichloroethylene), where PP weakens
Not Recommended
- Concentrated oxidising agents (chromic acid, permanganate) — attack the PP substrate
- Fuming nitric acid and fuming sulphuric acid (oleum), which attack the PP substrate
- Chlorosulphonic acid, which attacks the PP substrate
- Halogens (chlorine gas, bromine), which attack the PP substrate
- Nonpolar solvents above 80 °C such as decalin and tetralin, which dissolve PP
Environmental Ratings
Weather Resistance
Good. The PTFE membrane is inherently UV and weather resistant, though the PP substrate may degrade with prolonged UV exposure.
Ozone Resistance
Excellent (PTFE is fully inert to ozone)
UV Resistance
PTFE layer excellent; PP substrate limited. Use the UV-stabilised PP variant for outdoor exposure.
Standards & Certifications
Standards Compliance
Common Applications
- Protective venting for IP-rated electronics enclosures
- Sterile air and gas filtration (0.2 µm pore size)
- Dust collection and baghouse filter media
- Chemical fume extraction and laboratory vent filtration
- Moisture barriers preventing condensation in sealed enclosures
- Automotive sensor protection and battery venting
- Medical device venting (drug delivery, diagnostics, wearables)
- Aerosol and particulate monitoring and sampling
- Gas/liquid phase separation using hydrophobic barrier properties
- Pressure equalisation vents for outdoor enclosures and lighting
Not Recommended For
- Not a gasket or sealing material. Microporous by design, it does not create a fluid-tight seal.
- Temperature limited to 80 °C continuous by the PP substrate (PTFE alone tolerates 260 °C)
- PP substrate attacked by strong oxidising acids, halogens, and aromatic solvents at elevated temperature
- No compressibility or recovery data, as it is not designed for bolt-loaded flanged joints
- Very thin (under 0.5 mm), requiring mechanical support in most installations
- Not for continuous liquid immersion in aggressive solvents
Available Grades
Brands we stock: Porex, Sterlitech, Donaldson, GVS
0.2 µm Membrane (Sterile Filtration)
Fine-pore grade for sterile air and gas filtration, bacterial retention, and cleanroom applications. Highest water entry pressure of the standard grades.
0.45 µm Membrane (General Filtration)
General-purpose filtration grade balancing particle capture efficiency with air flow rate. Suited to dust collection, fume extraction, and industrial venting.
1.0 µm Membrane (Venting / Coarse Filtration)
Coarser pore grade with higher air permeability for protective venting, pressure equalisation, and applications where maximum airflow matters more than fine particle capture.
Need PTFE/PP Composite Membrane?
We supply ptfe/pp composite membrane in sheet, roll, and custom die-cut forms. Contact our team for pricing, data sheets, or technical assistance.
Disclaimer
This resource is provided for general engineering reference only and does not constitute professional advice, specification, or guarantee of performance. Actual results depend on specific application conditions. Universal Gaskets Pty Ltd accepts no responsibility or liability for decisions made based on this information. For full terms, see our Terms & Conditions.