We investigated the tribological interaction between polytetrafluoroethylene (PTFE) and silicon oxide surfaces. A simple rig was designed to bring about a friction between the surfaces via sliding a piece of PTFE on a thermally oxidized silicon wafer specimen. A very mild inclination (~0.5°) along the sliding motion was also employed in order to monitor the tribological interaction in a gradual...

−Hydrophobic polydimethylsiloxane polytetrafluoroethylene (PDMS-PTFE) flat-sheet membranes for pervaporation (PV) of chloroform from aqueous solution were successfully fabricated by solution casting method. The structures and the performance of the membranes was characterized by X-ray diffraction (XRD), scanning electron microscope combined with energy dispersive X-ray spectroscopy (SEM-EDXS), ...

Platinum (Pt) with foreign components has been considered as an effective approach to overcome CO poisoning, enhance the activity and decrease the usage of expensive Pt in fuel cells. In particular, PtFe is one of the superior binary Pt-based nanomaterial electrocatalysts for formic acid oxidation, which exhibits high resistance to CO poisoning and is a potential candidate for CO-tolerant alloy...

BACKGROUND AND AIM  Transjugular intrahepatic portosystemic shunt (TIPS) with polytetrafluoroethylene-(PTFE)-covered stent has been increasingly used for patients with complications of portal hypertension. It is still debated whether the new endoprostheses will improve some clinical outcomes (except for shunt patency) compared to the bare stents. The aims of our meta-analysis were to explore th...

We have done an experimental study in lambs in which we investigated the influence of flow rate on free microvascular flaps using polytetrafluoroethylene (PTFE) vascular grafts. We set up five surgical groups in which blood flow was progressively increased through the PTFE vascular graft. In group I (venous autograft) we observed just one vascular thrombosis which was located at the site of the...

OBJECTIVE The aim of this study was to compare the results of application of 2 types of superelastic nitinol prostheses. STUDY DESIGN Temporal bones study with planned data collection. SETTING Tertiary referral center. SUBJECTS AND METHODS Malleostapedotomy was performed in 15 human temporal bones implanting 3 different prostheses: manually crimping polytetrafluoroethylene (MC-PTFE) pisto...

PURPOSE The purpose of this study was to compare the sealing ability of temporary restorative materials at 24 hrs and 1 week. MATERIALS AND METHODS Endodontic access cavities were prepared in 56 extracted lower incisor-teeth and divided into 5 groups (n=10). Standard 5 mm deep access preparations were completed and root canals were prepared to size ISO #30 file. The access cavities were resto...

The addition of different polymers, such as polytetrafluorethylene (PTFE), to denture base resins could be an option to modify acrylic resin mechanical properties. This study evaluated the surface hardness, impact and flexural strength, flexural modulus and peak load of 2 acrylic resins, one subjected to a long and another subjected to a short polymerization cycle, which were prepared with or w...

PTFE-based coatings have been widely used, for example, on aluminium moulds for moulding of polyolefin packaging materials for its non-stick property. However, these coatings do not meet the users’ scratch resistance and durability requirements. This paper describes a preliminary study on the synthesis and characterization of a PTFE/sol-gel composite coating material which combines the required...