Fluorinated ethylene propylene VS PTFE

Fluorinated ethylene propylene kapena FEP ndi copolymer wa hexafluoropropylene ndi tetrafluoroethylene.Zimasiyana ndi PTFE (polytetrafluoroethylene) resins chifukwa ndi kusungunuka-processable ntchito ochiritsira jekeseni akamaumba ndi wononga extrusion njira.Fluorinated ethylene propylene anapangidwa ndi DuPont ndipo amagulitsidwa pansi pa dzina la mtundu wa polima FEP.Mayina ena ndi Neoflon FEP ochokera ku Daikin kapena Dyneon FEP ochokera ku Dyneon/3M.

FEP ndi yofanana kwambiri mu kapangidwe ka fluoropolymers PTFE (polytetrafluoroethylene) ndi PFA (perfluoroalkoxy polima resin).FEP ndi PFA onse amagawana zinthu zothandiza za PTFE zamakangano ochepa komanso osachitanso zinthu zina, koma zimapangika mosavuta.FEP ndi yofewa kuposa PTFE ndipo imasungunuka pa 260 °C;imaonekera kwambiri komanso imalimbana ndi kuwala kwa dzuwa.

FEP amapangidwa ndi free-radical polymerization wa zosakaniza za tetrafluoroethylene ndi hexafluoropropylene.Kusakaniza ndikokondera kuti kulipirire kuchepa kwa reactivity ya gawo la propylene.Njirayi imayambitsidwa ndi peroxydisulfate, yomwe imapanga homolyzes kuti ipange sulphate radicals.Chifukwa FEP sisungunuka bwino pafupifupi zosungunulira zonse, polymerization imachitika ngati emulsion m'madzi, nthawi zambiri amagwiritsa ntchito surfactant monga PFOS.Polima ili ndi pafupifupi 5% ya gawo la propylene.

Matebulo ofananitsa othandiza a PTFE motsutsana ndi FEP, PFA ndi ETFE atha kupezeka patsamba la DuPont, ndikulemba mndandanda wamakina, matenthedwe, mankhwala, magetsi ndi mpweya wamtundu uliwonse, mbali ndi mbali.

Pankhani ya kukana dzimbiri, FEP ndi fluoropolymer ina yokhayo yomwe imapezeka mosavuta yomwe ingafanane ndi kukana kwa PTFE kwa othandizira a caustic, chifukwa ndi mawonekedwe oyera a carbon-fluorine komanso opangidwa ndi fluorinated.

Kutentha, FEP imasiyana ndi PTFE ndi PFA pokhala ndi malo osungunuka a 260 ° C (500 ° F), pafupifupi madigiri makumi anayi kutsika kuposa PFA ndikutsikanso kuposa PTFE.

Pamagetsi, PTFE, FEP ndi PFA ali ndi ma dielectric constants ofanana, koma mphamvu za dielectric za FEP zimangoposa PFA.Komabe, pamene PFA ili ndi chinthu chofanana ndi PTFE, kutayika kwa FEP kuli pafupifupi kasanu ndi kamodzi ka PFA ndi EFTE (kupangitsa kukhala kokondakita wosagwirizana ndi electrostatic fields).

Mwamakani, FEP ndi yosinthika pang'ono kuposa PTFE.Mwina chodabwitsa, sichimapirira kupukutira mobwerezabwereza komanso PTFE.Imakhalanso ndi mphamvu yowonjezereka ya kukangana kosunthika, ndi yofewa ndipo imakhala ndi mphamvu yotsika pang'ono kuposa PTFE ndi PFA.

Chinthu chodziwika bwino cha FEP ndikuti ndipamwamba kwambiri kuposa PTFE muzinthu zina zokutira zomwe zimakhudzana ndi zotsukira.

Ethylene tetrafluoroethylene (ETFE), m'njira zambiri, imatha kuganiziridwa kuti ndi ya gulu losiyana, chifukwa ndi mtundu waukadaulo wapamwamba kwambiri wa ena omwe ali ndi zomwe zitha kuonedwa kuti ndizochepa pang'ono m'magawo ena poyerekeza ndi PTFE, FEP ndi PFA.