Perfluoroplastics applications

Perfluoroplastics have a multitude of useful properties. Any one of these properties may possibly be found in certain hydrocarbon-containing polymers, metals, or other materials. However, it is in the applications that require a combination of two or more of these properties where the perfluoroplastic finds unique utility. The unique properties and performance of perfluoroplastics are highly related to their structure. 

Foamed fluoroplastics have been used in coaxial cables since the 1960s, but they are receiving increased interest for twisted-pair applications since the dielectric performance of all solids can be improved by the uniform addition of voids. Current efforts focus on smaller and more uniform voids that can be incorporated into thin-walled products such as micro coaxial cables and twisted pair cables. The use of advanced foamed perfluoroplastic resins provides the cable designer with options for improving cable performance and/or reducing cable weight [14,15]. 

High MW PTFE tends to be favored in applications where the potential for extreme temperatures, harsh chemicals, and other extremely aggressive environments exist. This is particularly true when combined with high frequency requirements such as coaxial cable applications where the excellent dielectric properties are also required. Unfortunately, such FITE cannot be processed by conventional melt processing techniques. With the recent developments in foamed perfluoroplastic products, economical cables with properties very near to those of expanded PTFE are possible. 

The melt processible fluoroplastics are often desired due to the cost benefits of melt extrusion over paste extrusion. FEP, PEA and specially formulated melt processible perfluoroplastics are used in many of these applications however, in some of these applications, perfluoroplastics may not be the ideal choice. In cases where high cut-through resistance and better tensile properties are required, it is often desirable to employ a partially fluorinated polymer such as ETFE (ethylene-tetrafluoroethylene). ETFE is the copolymer of ethylene and TEE [16] that normally includes an additional termonomer to increase the flexibility required in commercial applications [17]. The increased physical and electronic interactions of the ETFE polymer chain are responsible for the comparatively enhanced physical properties. Additionally, the partially fluorinated polymers may be cross-linked to further improve physical properties. These benefits, however, are obtained at the expense of the unique properties of perfluoroplastics discussed in the Introduction and Overview. 

The incorporation of nanoparticles into polymers has generated considerable excitement and activity since the interfacial effects at that scale can impart significant physical property improvements [18], The low surface energy of perfluoroplastics increases the difficulty of producing fully exfoliated nanocomposites. The incorporation is easier with partially fluorinated compounds such as polyvinylidene fluoride (PVDF) or fluoroelastomers [ 19], but even PTFE compounds have been produced for wire and cable applications [20],... 

Perfluoroplastic dispersions which are formulated into paints find utility in many different, and sometimes unexpected, industrial applications. A few such examples are coatings on molds, coatings on automotive paint racks, coatings on air conditioner pistons, coatings on equipment and fasteners in the marine environment, coatings for down-hole oil and gas applications, and coatings inside metered dose inhalers. 

Automotive paint racks are used to hold parts while they are being painted and these racks must be used with several different colors. The perfluoroplastic coatings when applied to automotive paint racks allow the user to easily and quickly remove paint on the support rack with a simple high pressure water lance. In this application, both the nonstick property and the chemical resistance of the perfluoroplastic coating to the automotive paint formulation are critical. 

Perfluoroplastic coatings may be found on the inside of many metered dose inhalers. In this application, the objective is to keep all active ingredients dispersed in the fluid media. The thin perfluorinated surface provides a very nonreactive and impermeable barrier. As a result, the organic active ingredients are prevented from partitioning to the container wall and thereby changing the concentration of the drug to be delivered. 

Fluoroplastics are, generally, slippery materials with smooth surfaces due to their low coefficients of friction. The coefficient of friction decreases with an increase in fluorine content. Numerous mechanical applications depend on low friction of these plastics with little or no lubrication. In the case of perfluoroplastics, such as PFA, FEP, and PTFE, dynamic coefficient of friction is larger than static coefficient of friction. It... 

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