Expandable polytetrafluoroethylene

The success of this and the other operations derives from the correct application of back-pulse filtration principles, in particular the back-pulse step itself in which the filter cloths are cleaned and made ready for further filtration. The properties of the GORE-TEX membrane, composed of expanded polytetrafluoroethylene, give rise to the desirable results of these brine filtrations, in particular ... 

Table 1. Comparison of the respective evolution of the compliancies of a natural artery on the one hand and of an expanded polytetrafluoroethylene prosthesis on the other hand when the blood pressure increases...

Fig. 3. Microstructure of expanded polytetrafluoroethylene as shown by scanning eiectron microscopy with different intemoduiar species (a) 30 m (b) 90 m (c) 12 nm. (N Noduies, F Fibrilles)...

Fig. 5. Vascular prosthesis made of micoporous polytetrafluoroethylene, also known as expanded polytetrafluoroethylene.

Fig. 6. Tubular conduit made of expanded polytetrafluoroethylene wrapped into a thin sheath, which is also made of polytetrafluoroethylene the photograph shows the ability of the sheath to detach from the main wall surface.

F. J. Veith, S.K. Gupta, E. Ascer, S. White-Flores, R.H. Samson, L.A. Scher, J.B. Town, V.M. Bernard, P. Bonier, W.R. Flinn, P. Astelford, J.S.T. Yao, J.J. Bergan, Six-year prospective multicenter randomized comparison of autologous saphenous vein and expanded polytetrafluoroethylene grafts In Infraingulnal arterial reconstructions, J. Vase. Surg. 3(1) (1986) 104-114. 

Polytetrafluoroethylene suture is composed of expanded polytetrafluoroethylene (ePTFE), resulting in a porous microstructure having longitudinally oriented nodes and fibrils. The suture is sold by W. L. Gore Associates, Inc. under the trade name Gore-Tex Suture. 

Godin MS, Waldman SR, Johnson Jr CM. The use of expanded polytetrafluoroethylene (Gore-Tex) in rhinoplasty. A 6-year experience. Archives of Otolaryngology Head and Neck Surgery 1995, 121, 1131-1136. 

Hurst BS. Permanent implantation of expanded polytetrafluoroethylene is safe for pelvic surgery. United States Expanded Polytetrafluoroethylene Reproductive Surgery Study Group. Human Reproduction 1999, 14, 925-927. 

Sporting equipment would be much more primitive. Skis would be wooden and ski boots, leather. Ski clothing, too, would be heavy and bulky, because it would be made of wool—no polypropylene to wick perspiration away from the body, no fleece, or breathable, waterproof expanded polytetrafluoroethylene (PTFE) such as GoreTex. Baseball, football, and soccer would be played outdoors in stadiums with real grass, a situation that some would prefer. The balls would get quite heavy in the rain, because they would be covered in leather. Football helmets, too, would be leather and would not offer much protection. A good golfer would drive a golf ball about 40 to 50 yards fewer. Cameras would be very heavy and awkward. 

One of the most successful industrial applications of polymeric catalytic membranes is the Remedia Catalytic Filter System to destroy toxic gaseous dioxins and furans from stationary industrial combustion sources by converting them into water, CO2, and HCl. The system consists of an expanded polytetrafluoroethylene (PTFE) microporous membrane, needle-punched into a scrim with a catalytically active PTFE felt. The catalyst is a V2O5 on a Ti02 support. The microporous membrane captures the dust but allows gases to pass to the catalyst where they are converted at temperatures as high as 260° C. 

More recently, W. L. Gore Associates, Inc. [31] have used expanded polytetrafluoroethylene (ePTFE) porous films and PFSA resin solutions to produce a composite membrane. In this process, the PFSA solution was brushed onto both sides of the ePTFE film so as to impregnate and substantially occlude the interior volume of the film a nonionic surfactant (5%, w/v) was then added into the PFSA solution as a penetrant. The surfactant was removed by soaking in isopropanol after drying at 140 °C (this procedure was repeated several times so as to fully occlude the interior... 

Sapsford, R. N., Oakley, G. D., and Talbot, S. (1981). Early and late patency of expanded polytetrafluoroethylene vascular grafts in aorta-coronary bypass. J. Thorac. Cardiovasc. Surg. 81, 860-864. 

U., Zilla, P., In vitro endothelialization of expanded polytetrafluoroethylene grafts a clinical case report after 41 months of implantation. J. Vase. Surg., 1997, 25(4) 757-763. 

In the cardiovascular area, PET has a dominant position with heart valves. Expanded polytetrafluoroethylene, known for its chemical inertia and its high-thermal stability, possesses other advantages compared with PET, especially its biostability and the possibility of sterilization by heat. Finally, substitutes based on synthetic textiles now open up an alternative therapy for the replacement of injured... 

Expanded polytetrafluoroethylene (PTFE) grafts have gained increasing popularity as synthetic or nontextile grafts for reconstructive procedures, such as, above- or helow-the-knee bypasses for limb salvage. 

J. Yang, D. Motlagh, J.B. Allen, A.R. Webb, M.R. Kibbe, O. Aalami, M. Kapadia, T.J. Carroll, G.A. Ameer, Modulating expanded polytetrafluoroethylene vascular graft host response via citric acid-based biodegradable elastomers, Adv. Mater. 18 (2006) 1493-1498. 

M. Hosiers, K. Deloose, J. Verbist, H. Schroe, G. Lauwers, W. Lansink, P. Peeters, Heparin-bonded expanded polytetrafluoroethylene vascular graft for femoropopliteal and femorocrural bypass grafting 1-year results, J. Vase. Surg. 43 (2006) 313-318. 

D.L. Akers, Y.H. Du, R.F. Kempezinski, The effect of carbon coating and porosity on early patency of expanded polytetrafluoroethylene grafts—an experimental study, J. Vase. Surg. 18 (1993) 10-15. 

I. Baek, C.Z. Bai, J. Hwang, J. Park, J.S. Park, D.J. Kim, Suppression of neointimal hyperplasia by sirolimus-eluting expanded polytetrafluoroethylene (ePTFE) haemodialysis grafts in comparison with paclitaxel-coated grafts, Nephrol. Dial. Transplant. 27 (2012) 1997-2004. 

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