ECTFE properties

Fluoroplastic FPs have superior heat and chemical resistance, excellent electrical properties, but only moderate strength. Variations include PTFE, FEP, PFA, CTFE, ECTFE, ETFE, and PVDF. Used for bearings, valves, pumps handling concentrated corrosive chemicals, skillet linings, and as a film over textile webs for inflatables such as pneumatic sheds. Excellent human-tissue compatibility allows its use for medical implants. 

Ethylene carbonate, 10 640, 665 in lithium cells, 3 459 molecular formula, 6 305t physical properties, 6 306t transesterification of, 13 651-652 Ethylene-carbon monoxide (ethylene-CO) copolymers, 5 9 10 197 Ethylene chlorohydrin process, 10 640 Ethylene-chlorotrifluoroethylene (E-CTFE) alternating copolymer (ECTFE), 15 248... 

Figure 4.93 displays two examples of tensile stress (TS) and modulus retention (relative to the properties at 20° C) versus temperature for an ECTFE. 

Examples of fluoroplastics include polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), ethylene—chlorotrifluoroethylene (ECTFE), ethylene—tetrafluoroethylene (ETFE), poly(vinylidene fluoride) (PVDF), etc (see Fluorine compounds, organic). These polymers have outstanding electrical properties, such as low power loss and dielectric constant, coupled with very good flame resistance and low smoke emission during fire. Therefore, in spite of their relatively high price, they are used extensively in telecommunication wires, especially for production of plenum cables. Plenum areas provide a convenient, economical way to run electrical wires and cables and to interconnect them throughout nonresidential buildings (14). Development of special flame-retardant low smoke compounds, some based on PVC, have provided lower cost competition to the fluoroplastics for indoors application such as plenum cable, Riser Cables, etc. 

PCTFE has better mechanical properties than PTFE because the presence of the chlorine atom in the molecule promotes the attractive forces between molecular chains. It also exhibits greater hardness, tensile strength, and considerably higher resistance to cold flow than PTFE. Since the chlorine atom has a greater atomic radius than fluorine, it hinders the close packing possible in PTFE, which results in a lower melting point and reduced propensity of the polymer to crystallize.7 The chlorine atom present in ECTFE, a copolymer of ethylene and CTFE, has a similar effect on the properties of the polymer. 

Halar ECTFE (ethylenechlorotrifluoroethylene) This material is an alternating copolymer of ethylene and chlorotrifluroethylene. This fluoropolymer withstands continuous exposure to extreme temperatures and maintains excellent mechanical properties across this entire range (from cryogenic temperatures to 180°C). It has excellent electrical properties and chemical resistance, having no known solvent at 121°C. It is also nonbuming and radiation-resistant. Its ease of processing affords a wide range of products. 

Some of the thermal properties of perfluoro-alkoxy polymers (PFA and MFA) and FEP have been listed in Tables 3.62 and 3.63. Table 3.64 and Fig. 3.93 provide similar data for PVDF and Tables 3.65 and 3.66 for ETFE and ECTFE. 

Some electrical properties of ECTFE are given in Table 3.80. The dielectric strength (ASTM D149) is higher than the breakdown strength of PVDF. 

Table 3.80. Typical Electrical Properties of ECTFE Film at 23°C[ i...

Levyt has described a process for orienting fluoropolymer films using a combination of two rolls (Fig. 6.29) rotated at different speeds while the film was heated to a temperature above its second transition temperature, typically between 145°C and 175°C. Roll B rotates at a faster speed than roll A, resulting in the stretch, where the ratio of the speed of roll B to roll A is equal to the stretch ratio (SR). The stretched film was cooled below the second transition temperature of the pol5mier while it was held under tension. Levy reported that orientation in longitudinal direction (LD) imparted improvement in the mechanical property of the film in the transverse direction (TD). Table 6.13 shows the composition of ETFE and ECTFE resins in this study. Tables 6.14-6.16 present the properties of these resins as a function of stretch ratio. A stretch ratio of 0 was indicative of as-cast, unstretched film. Note that in the absence of any stretch in the transverse direction, with... 

Tabie 6.13. Composition (Mole%) and Properties of ETFE and ECTFE Resins ... 

Table 6.15. Mechanical Properties of an ECTFE Film as a Function of Stretch Ratio ...

Some halogenated solvents can cause ECTFE to become slightly plasticized when it comes into contact with them. Under normal circumstances, that does not impair the usefulness of the pol)nner. When the part is removed from contact with the solvent and allowed to dry, its mechanical properties return to their original values, indicating that no chemical attack has taken place. As with other fluoropolymers, ECTEE will be attacked by metallic sodium and potassium. 

The useful properties of ECTFE are maintained on exposure to cobalt-60 radiation of 20 Mrads. ECTFE also exhibits excellent resistance to weathering and UV radiation. Table 2.13 shows the compatibility of ECTEE with selected corrodents. Reference [1] provides a more extensive listing. 

The useful properties of ECTFE are maintained on exposure to cobalt-60 radiation of 200 Mrads. 

TABLE 52.15. Mechanical properties measured at200 °C of an ECTFE polymer after y-irradiation. 

Ethylene chlorotrilluoroethylene (ECTFE) is an alternating copolymer of chlorotrifluo-roethylene and ethylene. It has better wear properties than PTFE along with good flame resistance. Applications include wire and cable jackets, tank linings, chemical process valve and pump components, and corrosion-resistant coatings. ... 

Ethylene chlorotrifluoroethylene copolymer (ECTFE, E/CTFE) n. A fluoroplastic with good mechanical, thermal, electrical, processing, and resistance properties. 

Ethylene-chlorotrifluoroethylene copolymer (ECTFE) has a linear macromolecule in which the predominant alternating copolymer is [—(CHJj-CFj—CFCl—] . This copolymer exhibits useful properties for a wide range of temperatures, that is, from cryogenic temperatures up to 180 C. Its permittivity is low but stable over a broad temperature and frequency range. 

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