Perfluoroalkoxy plastic

Abbreviations for plastics ABS, acrylonitrile-butadiene-styrene CPVC, chlorinated poly vinyl chloride ECTFE, ethylene-chlorotrifluoroethylene ETFE, ethylene-tetrafluoroethylene PB, polybutylene PE, polyethylene PEEK, poly ether ether ketone PFA, perfluoroalkoxy copolymer POP, poly phenylene oxide PP, polypropylene PVC, polyvinyl chloride PVDC, poly vinylidene chloride PVDF, poly vinylidene fluoride. 

Teflon PFA (perfluoroalkoxy). This plastic is translucent and slightly flexible. It has the widest temperature range of the fluoropolymers — from -270°C to +250°C — with superior chemical resistance across the entire range. Compared to TFE at +277°C, it has better strength, stiffness, and creep resistance. PFA also has a low coefficient of friction, possesses outstanding antistick properties, and is flame-resistant. 

The family of FPs, also called fluorocarbon plastics, is based on polymers made of monomers composed of fluorine and carbon may also include chlorine atoms in their structure. Specific types include polytetrafluoroethylene (PTFE), polytetrafluoroethylene-cohexafluoro-propylene or fluorinated ethylene propylene (FEP), polytrafluoroethylene-coperfluoropropylvinyl ether (PFA), ethylenetetrafluoroethylene (ETFE). polychlorotrifluoroethylene (PCTFE), ethylene-chlorotri-fluoroethylene (ECTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfluoromethylvinylether (PFMV), perfluoroalkoxy (PFA), etc. 

Storage of water samples to detect trace metals is normally carried out in plastic containers fluorinated plastic materials i.e.. Teflon, fluorinated ethylene propylene (FEP), perfluoroalkoxy polymers (PFA) or polyethylene are used because if opportunely treated and conditioned they guarantee contamination-free samples. However, FEP or Teflon bottles are preferable to those made of polyethylene when speciation studies are carried out. In fact, polyethylene over long periods of storage can release plasticizers (above all phthalates or amines), which behave as ligands and modify the complexation equilibria of the solution. When Hg is to be determined plastic materials must be avoided because they are permeable to gases and vapours glass or quartz are therefore used. 

A helical blade used in fluid compressors made of plastics, such as PTFE, PFA (perfluoroalkoxy resin), PEEK (polyetheretherketone), PES (polyether sulfone). 

Some plastics are more inert and more pure than others, so thought should be given as to which one is optimal for your samples. Selection should be made based on the suite of elements being analyzed, analyte concentration levels, matrix components, or whether it is an aqneons-, acid-, or organic-based solution. Some of the most common plastic materials used in the manufacture of sample preparation vessels and sample introduction components inclnde polypropylene (PP), polyethylene (PE), polysulfide (PS), polycarbonate (PC), polyvinylchloride (PVC), polyvinylfluoride (PVF), perfluoroalkoxy (PFA), and polytetrafluoroethylene (PTFE). 

Polymers should be tested for extractables before use. The amount of extractable material is determined by the formulation of the polymer mix. Molded plastics often have a high plasticizer content to make them more fluid for molding. These low molecular weight plasticizers migrate to and contaminate the surface. In semiconductor processing, a relatively inert fluoropolymer (perfluoroalkoxy (PFA), e.g. Teflon or Neoflon ) is often used for containers and holders but they can hberate corrosive fluorine compounds. Special treatments are used to reduce the extractable fluoride compounds from these materials. Many polymers can absorb water vapor and corrosive gases from the environment. 

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