PFA

Teflon PFA [FLUORINE COMPOUNDS, ORGANIC - TETHAFLUOROETHYLENE-PERFLUOROVINYLETHERCOPOLYPffiRS] (Vol 11) -organic mat ls in carbon dioxide [SUPERCRITICAL FLUIDS] (Vol 23)... 

FLUORINECOMPOUNDS,ORGANIC - TETRAFLUOROETHYLENE-PERFLUOROVINYLETTiERCOPOLYTffiRS] (Vol 11) PFA. See Perfluoroalkoxy fluorocarbon resins. 

These ethers readily copolymerize with tetrafluoroethylene and other fluoroalkenes to commercially significant plastics, elastomers, and ion-exchange resins such as Teflon PFA, Kalrez, andNafton (see Fluorine compounds organic-tethafluoroethylene-perfluorovinylETHERcopolya rs EuASTOPffiRS, SYNTHETIC-FLUOROCARBONELASTOTffiRS lONIC POLYTffiRS). 

Peifluoioalkoxy (PFA) fluoiocaibon lesins aie designed to meet industry s needs in chemical, electrical, and mechanical appHcations. These melt processible copolymers contain a fluorocarbon backbone in the main chain and randomly distributed perfluorinated ether side chains ... 

Unfilled Teflon PFA has been tested in mechanical appHcations using Teflon FEP-100 as a control (24). Tests were mn on molded thmst bearings at 689.5 kPa (100 psi) against AISI 1080, Rc 20,16AA steel, and at ambient conditions in air without lubrication. A limiting PV value of 5000 was found. Wear factors and dynamic coefficients of friction are shown in Table 4. 

Table 4. Teflon PFA Fluorocarbon Resin Thrust-Bearing Wear-Test Results ...

Optical Properties and Radiation Effects. Within the range of wavelengths measured (uv, visible, and near-ir radiation), Teflon PFA fluorocarbon film transmits slightly less energy than FEP film (29) (Table 6). In thin sections, the resin is colorless and transparent in thicker sections, it becomes translucent. It is highly transparent to it radiation uv absorption is low in thin sections. Weather-O-Meter tests indicate unlimited outdoor life. 

Like other perfluoropolymers. Teflon PFA is not highly resistant to radiation (30). Radiation resistance is improved in vacuum, and strength and elongation ate increased more after low dosages (up to 30 kGy or 3 Mrad) than with FEP or PTEE. Teflon PEA approaches the performance of PTEE between 30 and 100 kGy (3—10 Mrad) and embrittles above 100 kGy (10 Mtads). At 500 kGy (50 Mrad) PTFE, FEP, and PFA ate degraded. The effect of radiation on tensile strength and elongation is shown in Table 7. 

Sample 250-pm compression-molded films of Teflon PFA 340 from G.E. resonance transformer 2 MeV capacity, at a current of 1 m A. 

The cycle can usually be estimated on the basis of about 30 s/3 mm of thickness most of it is devoted to ram-in-motion time (except for very thin sections). The mold temperature used with PFA 340 is often the highest temperature that allows the part to be ejected undamaged from the mold and retain its shape while cooling. 

PFA-F/uoroearbon Molding and Extrusion Materials, ASTM 3307-86, American Society for Testing and Materials, Philadelphia, Pa., 1987. 

PFA Fluorocarbon Kesins, sales brochure, E08572, E. I. du Pont de Nemours Co., Inc., Wilmington, Del. 

Teflon PFA Fluorocarbon Fesins Teflon PFA Fluorocarbon Fesins . Teflon PFA Fluorocarbon Fesins ... 

E. W. Easig, D. I. McCane, and J. R. Perkins, paper presented at the 22ndIntemational Wire and Cable Symposium, Adantic City, N.J., Dec. 1973. Handbook of Properties forTeflon PFA, sales brochure, E46679, E. I. du Pont de Nemours Co., Inc., Wilmington, Del., Oct. 1987. 

Carbon steel Sch. 40 Fiberglass reinforced polyester Fiberglass reinforced vinylester Glass pipe Aluminum Sch. 40 304 stainless steel Sch. 5 Saran-lined steel Polypropylene- lined steel Rubber-linedsteel Sch. 40 316 stainless steel Sch. 5 304 stainless steel Sch. 40 Kynar-Ifned steel 316 stainless steel Sch. 40 Alloy 20 Sch. 5 FEP Teflon-lined steel PFA Teflon-lined steel Armored-glass pipe PTFE Teflon-lined steel Monel 400 Sch. 5 Nickel 200 Sch. 5 Alloy 20 Sch. 40 Monel 400 Sch. 40 Inconel 600 Sch. 5 Titanium Sch. 5 Nickel 200 Sch. 40 Titanium Sch. 40 Inconel 600 Sch. 40 Glass-lined steel Sch. 40 Hastelloy C-276 Sch. 5 Zirconium Sch. 5 Hastelloy B Sch. 5 Zirconium Sch. 40 Hastelloy C-276 Sch. 40 Hastelloy B Sch. 40 Tantalum-lined steel Sch. 5 Tantalum-lined steel Sch. 40... 

Property ASTM test PTFE PCTFE PVF - PVDF TFE-HFP TFE- ethylene PFA... 

In 1972 Du Pont introduced Teflon PFA, a copolymer of tetrafluoroethylene and perfluorofpropyl vinyl ether) (CF2 = CFOCF2CF2CF3). Similar materials are now also produeed by Asahi Glass, Daikin, Hoechst and Monteflos and are commonly referred to as PFA fluoropolymers. In 1994 Hoechst introduced Hostaflon PFA-N, claimed to have significantly lower melt viscosities than earlier grades of material. 

Properties are similar to those of PTFE, and PFA fluoropolymers are generally considered to be the best melt-processable alternative to PTFE yet available. They are, however, more expensive than PTFE. Compared with the TFE-FEP copolymers such as Teflon I P the PFA fluoropolymers ... 

Somewhat between PTFE and PFA materials is the product Hostaflon TFM, which is a copolymer of TFE and a small amount of the perfluoro(propyl vinyl ether). It has improved impact strength and weldability and has been promoted as a suitable material for forming into bottles. Yet another TFE-perfluoroalkoxy copolymer was introduced by Du Pont in 1979 as Teflon EPE. This material had a somewhat lower melting point (295 °C) than the more common PFA fluoropolymers but it is no longer marketed. 

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