Publish Time: 2021-08-14 Origin: Site
PTFE membrane is a microporous membrane produced by special processes such as premixing, extrusion, calendering, and biaxial stretching using polytetrafluoroethylene dispersion resin. It is mainly divided into clothing membranes, waterproof membranes, filter membranes, and purification membranes. The high-quality PTFE membrane has a fibril-like microporous structure with a porosity of over 85%. There are 1.4 billion micropores per square centimeter, and the pore size ranges from 0.02μm-15μm.
The surface morphology of the PTFE microporous film is a spider web-like microporous structure. Pores are formed between the microfibers, and the arrangement direction of the microfibers is basically parallel to the stretching direction.
PTFE membranes are commonly used as highly effective and breathable waterproof materials and fabrics. PTFE can also be used for PTFE cable film, PTFE cable wrape tape, PTFE unsintered tape and PTFE sealing film roll.
The PTFE waterproof and breathable membrane has very small water particles in the state of water vapor. And these water vapor particles can permeate along the pores of the PTFE waterproof membrane until the capillary (membrane) reaches the other side, causing air permeability. If the water vapor condenses and turns into water droplets, the particles will become larger. In addition, the surface tension of the water droplets acts in it, and the water molecules cannot leave the water droplets smoothly and permeate back to the original side. In other words, such a process can prevent the occurrence of water penetration, that is, it can well isolate water and other liquids from the outside, so that the PTFE waterproof and breathable membrane material truly has the function of waterproof and breathable.
Waterproof, breathable and permeable mechanism of PTFE porous membrane
Waterproof and breathable membranes depend on the structure and surface wettability of the membrane. PTFE porous membrane has the excellent performance of ordinary textile fabrics and high-tech micropores. The film can be laminated to fabric to have water-proof, wind-proof and heat-resistant properties. It is ideal for firefighter clothing, sports and leisure clothing, and military equipment. It is the main development direction of waterproof and breathable materials.
1. Good high temperature resistance. The working environment temperature of PTFE membrane with high temperature resistance can reach 250℃.
2. Good low-temperature resistance and toughness. PTFE waterproof and breathable membrane has high strength and mechanical toughness, even if the temperature drops to about -200 ℃, it can maintain 5% elongation.
3. Good corrosion resistance. PTFE waterproof and breathable membranes have strong active chemical substances and solvents for a large part of the existing ones, and can show resistance to strong acids and alkalis and various organic solvents without interaction.
4. The effect of high lubricity is good. PTFE waterproof and breathable membrane is a material with good friction resistance among most waterproof and breathable solid materials.
In short, waterproof and breathable PTFE film is a new type of polymer waterproof and breathable material developed in recent years. In terms of raw material production and processing technology, the processing technology indicators of PTFE waterproof and breathable membrane raw materials are much higher than ordinary waterproof and breathable materials. At the same time, from the perspective of the quality of waterproof and breathable materials, PTFE waterproof and breathable membranes also have unique functional characteristics that other waterproof materials do not have.