Fluoropolymers categories

All of the unique properties imparted by fluorocarbons can be traced back to a single origin the nature of the C—F bond. These properties include low surface tension, excellent thermal and chemical stability, low coefficient of friction, and low dielectric constant. However, not all of these properties are possessed by the entire inventory of available fluorocarbons. The fluorocarbons can be assigned to two major categories (1) fluoropolymers, which are materials that are comprised mainly of C—F bonds and include such examples as PTFE, and (2) fluorochemicals (FA) based on the perfluoroalkyl group, which are materials that generally have fewer C—F bonds and often exist as derivatives of other classes of molecules (e.g., acrylates, alcohols, esters). In addition, the properties that dictate the uses of fluorocarbons can be classified into (1) bulk properties (e.g., thermal and chemical stability, dielectric constant) and (2) surface properties (e.g., low surface tension, low coefficient of friction). The types of materials available and properties imparted are not exclusive and overlap substantially. From this array of fluorocarbons and attributes, a large variety of unique materials can be constructed. 

PEMFC (proton exchange membrane) uses fluoropolymer or similar type membranes such as SPEEK. Microbial and direct methanol fuel cells fall into this category also. 

An engineer has a wide choiee of materials of eonstruetion for eorrosion control. There are three broad categories of materials, used either individually or in combination with each other metals, polymers, and ceramics. This chapter describes the differences between them and explains the phenomenology of applications of polymer-based materials. It also places fluoropolymer materials in their appropriate contexts. Polymer-based materials are also known as polymeries, polymeric materials, or simply plastics, which is often not accurate and can lead to confusion. 

Also within this category of application is the field of radiation grafting onto pre-existing polymeric substrates. E-beam or gamma sources can be used to initiate grafting onto a range of materials, for example poly(olefin)s, fluoropolymers, and cellulosics. The biocompatibility of poly(olefin)s can be greatly... 

Since the density of plastics highly depends on the presence of fillers or other additives, this property is far from being a characteristic feature. Unfilled polyolefines (polyethylene and polypropylene), a number of elastomers (natural rubber and silicone rubber), and foamed plastics come within the rare category of polymers which float on water. Some fluoropolymers exhibit a density around or greater than 2 g/cvo (see also Table 3.3). 

The fluoropolymer materials are the most important for the chemical process industry. There are two categories of fluoropolymers the fully fluorinated and the partially fluorinated. 

Surface modification of the polymeric membranes via molecular design is one of the most versatile means to improve the surface properties without affecting bulk properties. Surface modification of fluoropolymer membranes, especially for fully fluorinated polymer membranes, such as PTFE membranes, has been of particular interest, due to their physical and chemical inertness. Surface modification of fluoropolymer membranes can be classified into two categories surface coating and surface grafting. 

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