Different kinds of hydrophobic micro porous membranes

In the functional fabric lamination industry, hydrophilic membranes such as TPU, PU, and TPEE are widely used in outdoor hardshell jackets, windbreakers, mountaineering wear, down jackets, ski wear, and hiking shoes due to their excellent waterproof and moisture-permeable properties. These membranes can be laminated with various fabrics, it is suitable for 2-layer and 3-layer fabric constructions.

As the popularity of outdoor activities, consumers demand greater comfort in outdoor apparel. Good air breathability, excellent moisture permeability, superior waterproofing, and soft comfort have become the new benchmarks for outdoor performance wear. 

Traditional hydrophilic membranes can not meet the air breathability requirements, making micro porous membranes the industry's new favorite. However, with numerous microporous membranes available, how should we make the right choice?

1．PU micro porous film

By incorporating additives into polyurethane (PU) resin and specially processing the formed film t, micro porous \ are created throughout the membrane . These pore sizes are typically smaller than the diameter of water droplets but significantly larger than that of water vapor molecules. This structure allows air to pass through while blocking water penetration. The resulting membrane boasts a soft texture, high moisture permeability, and meets the requirements for most outdoor apparel. Furthermore, it is cost-effective with a high cost-performance ratio, making it widely applicable across various industries.

2．PTFE micro porous film

PTFE resin is subjected to a stretching process , which generates a vast network of interconnected microfibers and nodes within its structure, forming a microporous network. This membrane exhibits the highest water vapor transmission rate (WVTR), providing exceptional breathability. Simultaneously, it delivers a superior waterproof barrier performance. It  highly resists  chemicals , strong corrosion resistance, withstanding extreme temperatures , and offers a long service life.

However, this material cost highly , and PTFE contains fluorinated components, which can be harmful to human health and the environment , we all know that the proposal for strict restrictions on PFAS (per- and polyfluoroalkyl substances) was submitted by five countries from Europe to the European Chemicals Agency (ECHA) , once it is adopted , the the proposal could take effect as early as 2026.

3．POE micro porous film

The primary materials are polyethylene or polypropylene. A film is formed by adding fillers (such as calcium carbonate), blending, and extruding, followed by stretching . This kind of film is with Low density and lightweight properties, its production process is relatively clean and this material can be physical recycling . While the properties such as lower moisture permeability, weaker water pressure resistance , lower temperature resistance , make it not suitable to many applications .and these limitations restrict lamination process temperatures and application environment temperatures. Overall, its physical properties are weaker than PTFE and PU micro porous membranes. It is suitable for lightweight urban outdoor apparel or disposable protective clothing where high performance is not critical.

4．PP micro porous

Polypropylene (PP) is a thermoplastic polymer made from a combination of propylene monomers .Thermoplastic polypropylene polymer is produced into polypropylene microporous membrane through melt extrusion, stretching and other special processes .

During the stretching process, the membrane structure forms interconnected pores or channels, making it with air (moisture) permeability. The tiny pores are evenly distributed, with a diameter of about 0.02 microns. Liquids and solid particles cannot pass through, but water vapor and air can be permeable .

It is without DMF and PFAS ,   and also combines breathability and water resistance , so it is gradually  used to replace of PFTE film by many brands .

In all , property of different material is different , you can choose the proper one according to your application and request . For these four materials , PP micro porous film will be the best choose . PP film made by Nanxiong is tested by many famous brands , it is available for three in one lamination , it is not only with good moisture permeability , but also excellent water resistance , and water resistance keeps excellent even after 5 times washing . With there excellent performances , it is widely used for high-end outdoor garment for many famous brands .