PTFE membrane is a thin, highly porous film that behaves as an absolute retentive membrane. Their inherently hydrophobic nature make PTFE membranes ideal for applications such as filtering gases, aqueous aerosols, protecting vacuum pumps, or sterile venting fermentation tanks. PTFE is inert to most chemically aggressive solvents, strong acids and bases and can be used for solvent clarification and HPLC sample prep.
PTFE membranes are available unsupported and supported. PTFE membranes with a laminated polypropylene web support to one side offers improved handling characteristics. Chemical and thermal limitations are imposed by the backing.
PTFE and TFM are used for bellows in extreme corrosion resistance applications – specifically organic compounds, acids, and salts – as well as high temperature and high purity applications. They both exhibit non-stick behavior, and have a similar wide range of usage temperatures. However, there are significant differences between them, namely because TFM combines the best characteristics of both PTFE and PFA. TFM is the bellows material of choice when you need extremely low gas permeation, a longer fatigue life, and a smoother surface finish.
Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. The EPA estimates 5.7% of LDPE is recycled. Despite competition from more modern polymers, LDPE continues to be an important plastic grade.
PTFE is white by nature. So that is a redundant term. Other forms of Teflon like FEP and PFA are more translucent; def not white.
PTFE is more chemical resistant than your average automotive elastomer like neoprene and EPDM. That is a "better." Rubber will degrade well before a fluoropolymer is another way to say that.