Frequently Asked Questions

We have a Chemical Compatibility Chart that you can use for reference.

Sterlitech polyester track-etch (PETE) membrane filters are made from integral polyethylene terephthalate films. This construction ensures no potential for sloughing or particle shedding and broad chemical compatibility. Inherently hydrophilic, the filters do not require PVP treatment. They exhibit virtually the lowest extractables and adsorption characteristics for any polymeric membrane filters ensuring filtrate purity. Particles are retained on a flat, glass-like smooth surface with an even distribution in a single plane, facilitating microscopic and SEM analyses of the retentate. The PETE membrane filters have superior resistance to high operating pressures when used in appropriate holders.

Hydrophobic membrane filters are necessary for applications where the membrane is used to retain liquid water while allowing gases to pass through. Hydrophobic PCTE membranes typically have insufficient water entry pressures for these applications and will allow liquid water to pass at pressures lower than required. Hydrophobic PTFE and PETE membrane filters have the highest water entry pressures for membrane filters and are commonly used for these applications.

The Sterlitech polyester track-etch (PETE) membranes are made of polyethylene terephthalate.

It is possible to estimate the pore diameter of polyester track-etch (PETE) membranes from SEM images. In fact, this is how the pore size is characterized during manufacturing for most of the track-etch membranes. However, it is important to understand that there are calibration and performance variations between different SEMs. There is a good likelihood that a user’s results will not correlate to the manufacturing results that were used to characterize the membrane.