P - PTFE - PolytetrafluorethylenePTFE - Polytetrafluorethylene PTFE has no thermoplastic characteristics although it consists of linear, chemical chain molecules which are not linked. It is not possible to handle or form PTFE in the usual thermoplastic way. Nevertheless PTFE is a thermoplast because it can be sintered. For the production of shaped parts from PTFE the polymer is cold pressed as powder under high pressure into the desired form and sintered at temperatures around 380°C. PTFE is attacked only by elemental fluorine and chlorine tri fluoride at higher temperatures and pressures as well as by melting alkali metals. Otherwise it is resistant to all chemicals. A further advantage of polytetrafluorethylene: it has got the lowest coefficient of friction of all solids. However above 350°C PTFE burns in air to form noxious gases.
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