A hydrophobic PTFE membrane filter is used in many applications. These filters are used in atmospheric filtration and detection, as well as separating polar and nonpolar solvents. They also are a great choice for aqueous aerosol sampling.
Hydrophobic PTFE membranes can be fabricated using a variety of surface modification strategies. The coating process can alter the contact angle and reduce bacteria on the polymer composite. Moreover, the pore size of the membrane can affect the ability of the filter to remove particles.
During the manufacturing process, the polymer is coated with a layer of polydopamine (PDA), which is an adhesive polymer with amine and DOPA content. In addition, the surface of the PDA is coated with a hydrophobic PTFE layer. This results in a cobblestone-like structure, which has been shown to increase hydrophobicity.
PTFE membranes are a versatile alternative to glass and ceramic filters, due to their chemical inertness and ease of fabrication. Polytetrafluoroethylene is a high molecular weight polymer that has a low coefficient of friction. It is widely used in medical device coatings and pipework for reactive chemicals.
PTFE is also used in cookware. One of its most common uses is as a coating on catheters. Some studies have suggested that PTFE may be carcinogenic. However, the International Agency for Research on Cancer has concluded that there is insufficient data to determine whether there is a causal relationship between exposure to PTFE and cancer.
PTFE is an inert and chemically inert polymer that is resistant to virtually all solvents. It can be functionalized using paste extrusion.