Steam sterilization effect on the PET track-etched membranes properties

The article shows results of the steam sterilization influence on the PET track-etched membrane surface. The track-etched membranes were sterilized by the steam sterilization in two modes: 130-132°C at a pressure of 0.2 MPa (5 min); 120-121°C at a pressure of 0.11 MPa (20 min). The results showed that the steam sterilization changes the topography of the track-etched membranes surface and forms large oval-shaped protuberances in height 300-400 nm with a density of up to 0.007 protrusions/μm² with an average diameter of 3.0 μm, and also increases the surface roughness by 40%. The steam sterilization increases the hydrophility of track-etched membrane surface, increasing the contact angle on 9°-18° and reducing the total surface energy by 10-20%. The changes were primarily associated with surface degradation and hydrolysis reaction, which led to decarboxylation, cyclization and, as a result, an increase in cyclic trimmers on the PET track-etched membrane surface.