The results of the investigations into the technological formation of new wear-resistant polymer composites based on polytetrafluoroethylene (PTFE) filled with disperse synthetic and natural compounds are presented. The efficiency of using PTFE composites reinforced with carbon fibers depends on many factors, which influence the significant improvement of physicomechanical characteristics. The ...

Effects of mechanical compression and PTFE content on the through-plane gas permeability of gas diffusion layers (GDLs) of PEM fuel cells are investigated both experimentally and theoretically. A new test bed is designed and built which allows pressure drop and air flow rate measurement for various fibrous samples. The measured values are used to calculate the through-plane permeability. Variou...

Under macroscopic pin-on-disk testing the sliding friction coefficient of Polytetrafluoroethylene (PTFE) was investigated over a temperature range of approximately 200–400 K. This study examines the nature of the temperature dependence by testing PTFE pins at varying temperature and humidity on a linear reciprocating pin-on-disk tribometer. The friction coefficient increased monotonically with ...

OBJECTIVES To evaluate the budget impact of progressive replacement of standard polytetrafluoroethylene (PTFE) grafts by heparin-bound PTFE (Propaten) for below-the-knee (BTK) bypass in patients with critical limb ischaemia (CLI). DESIGN From a review of the scientific literature, we calculated a theoretical BTK primary patency for Propaten grafts. Using the French hospital expenditure databa...

BACKGROUND Treatment of lesions located in saphenous vein grafts (SVGs) is associated with increased procedural risk and a high rate of restenosis. METHODS AND RESULTS We conducted a randomized, multicenter trial to evaluate the usefulness of a polytetrafluoroethylene (PTFE)-covered stent compared with a bare stainless steel (SS) stent for prevention of restenosis and major adverse cardiac ev...

PURPOSE To analyze the long-term results of above-the-knee femoro-popliteal bypass (ATKFPB) with vein grafts compared with polytetrafluoroethylene (PTFE) grafts. METHODS A database of patients with chronic atherosclerotic occlusive disease who underwent ATKFPB was retrospectively reviewed. Characteristics of patient and arterial lesion, and follow-up results were compared between vein grafts ...

The aim of this study was to evaluate the feasibility of transjugular intrahepatic portosystemic shunts using FLUENCY expanded polytetraf luoroethylene (PTFE)-covered stents and the effect on the patency rate. A total of 114 cirrhotic patients who were treated by transjugular intrahepatic portosystemic stent shunt (TIPS) placement using a FLUENCY expanded, PTFE-covered stent were enrolled in th...

Past studies with PTFE nanocomposites showed up to 600× improvements in wear resistance over unfilled PTFE with the addition of Al2O3 nanoparticles. Irregular shaped nanoparticles are used in this study to increase the mechanical entanglement of PTFE fibrils with the filler. The tribological properties of 1, 2, 5 and 10 wt.% filled samples are evaluated under a normal pressure and sliding speed...

Silver nanolayers were sputtered on polytetrafluoroethylene (PTFE) and subsequently transformed into discrete nanoislands by thermal annealing. The Ag/PTFE composites prepared under different conditions were characterized by several complementary methods (goniometry, UV-visible spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy), and new data on the mechanism of Ag laye...

AIM This study aimed to evaluate clinical outcomes of titanium membrane and compare these findings with clinical outcomes of e-PTFE membrane, and to investigate the effect of bacterial contamination on both membranes with SEM during long-term healing. RESULTS Sixteen titanium and sixteen e-PTFE membranes were surgically placed adjacent to periodontally involved teeth. Seven titanium and 8 e-P...