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Polytetrafluoroethylene (PTFE)-coated glass fiber fabrics are used for long-lasting membrane structures due to their outstanding mechanical properties, chemical stabilities, and satisfying service life. During their operation time, different environmental impacts might influence their per-formance, especially regarding the mechanical properties. In this contribution, the impact of water on the tensile strength deterioration was assessed experimentally, providing evidence of consider-able but partially reversible loss of strength by up to 20% among the various types of investigated industrially established fabrics. OA Förderung 2021

Ever-increasing demands for high performance blood oxygenators have led to continuous advancements in this field. Despite the progresses made since their emergence, there still exist challenges that intimidate the reliability of membrane oxygenators. A promising approach for addressing these challenges and enhancing the overall process performance relates to the selection, development, and modification of materials with desirable characteristics. The main impetus for the present review is to bring forward important and yet less explored subjects by shedding light on the technological, design, and engineering aspects of oxygenators and the oxygenation process. Special attention is paid to membrane oxygenators and their essential characteristics such as gas transport, plasma leakage, and biocompatibility. Also, various practical configurations of membrane oxygenators are illustrated with their merits and limitations. From the materials perspective, a comprehensive range of polymeric materials with trackrecords for applications as membrane oxygenators are surveyed and analyzed considering their physicochemical and biocompatibility properties in order to gain insights into the features of an optimal material. In addition to elaborations on the methods for fabrication of membrane oxygenators, various effective techniques that could be used for altering the microstructure and surface properties of the membranes are presented. Also, an in-depth overview is provided about the transport phenomena in membrane oxygenators aiming to provide a better understanding of the molecular and process aspects of the process. An overview of the state of the art is summarized along with points about the trends of future developments are provided at the end.

Hydrophilic antibacterial silver decorated silica-grafted-poly(vinylpyrrolidone) (Ag-SiO₂-PVP) nanoparticles were successfully synthesized in multiple steps. In this regard, silanization of the silica nanoparticles was performed with different concentrations of vinyltrimethoxysilane (VTS) to generate vinyl groups onto the nanoparticles surface. Obtained results showed that by increasing the VTS concentration the amount of vinyl groups on the surface of the silica nanoparticles increased while nanoparticles agglomeration did not occur. Then, poly(vinylpyrrolidone) PVP brushes were grafted onto the silanized silica nanoparticles (SiO₂-VTS) via grafting-through polymerization method to obtain PVP-grafted silica nanoparticles (SiO₂-PVP). Fourier transform infrared spectroscopy, thermal gravimetric analysis, and dynamic light scattering confirmed the successful generation of the vinyl groups and PVP brushes onto the silica nanoparticles. Finally, Ag-SiO₂-PVP nanoparticles were prepared by synthesizing silver nanoparticles onto the SiO₂-PVP nanoparticles to render them antibacterial. Energy dispersive X-ray spectroscopy showed that highest grafting of silver nanoparticles onto the SiO₂-PVP nanoparticles was obtained for the nanoparticles with highest content of vinyl groups. X-ray photoelectron spectroscopy was used to identify the elements and their chemical structure for the synthesized nanoparticles. Plate colony counting method was applied to assess the antibacterial effects of the Ag-SiO₂-PVP nanoparticles which revealed outstanding bactericidal properties of them.