What Is PTFE Micro Porous Membrane?

PTFE (polytetrafluoroethylene) microfilm is made from PTFE powder as raw material and stretched through a series of special processes. It has a porous structure with a porosity of over 85%, and there are 1.4 billion micropores per square centimeter, with pore sizes ranging from 0.02μm to 1.5μm.

Process of PTFE micro porous membrane

The conventional process for making PTFE micro porous membrane is to mix PTFE raw materials, make the mixture into a sheet through rolling, and then stretch it in both directions to obtain the PTFE micro porous membrane. The process is as follows: PTFE raw materials - mixing - rolling - stretching.

As an environmentally friendly film, its main purpose is to control smoke emissions and collect products. According to the usage conditions, the film needs to have small pore sizes and high porosity in order to achieve low operating resistance and good collection effect while also having certain strength. The factors affecting the above indicators are mainly related to the preparation of the base film and the process conditions such as stretching temperature, speed, and stretching ratio.

Applications of PTFE micro porous membrane

PTFE clothing film

The pore sizes of PTFE clothing film range from 0.1μm to 0.5μm, which is hundreds of times smaller than the diameter of water molecules and tens of thousands of times larger than the diameter of water vapor molecules. It has excellent waterproof and breathable properties as well as windproof and thermal insulation functions. Clothing fabrics composite with PTFE film are widely used in sportswear, cold-resistant clothing, special clothing for the military, fire control, public security, medical care, and biochemical protection, as well as in footwear, hats, gloves, sleeping bags, tents, etc.