Fluoropolymer Monomer Synthesis: Tetrafluoroethylene;Hexafluoropropylene;Perfluoroalkyl Vinyl Ethers;Chlorotrifluoroethylene;Vinylidene Fluoride;Vinyl Fluoride.
Katundu wa Tetrafluoroethylene
Tetrafluoroethylene ndi gasi wopanda mtundu, wopanda fungo, wosakoma, wopanda poizoni yemwe amawotcha pa 76.3 C ndipo amasungunuka pa 142.5 C. Kutentha kwakukulu ndi kupanikizika kwa TFE ndi 33.3 C ndi 3.92 MPa.TFE imasungidwa ngati madzi;Kuthamanga kwa nthunzi pa 20 C ndi 1 MPa.Kutentha kwake kwapangidwe kumanenedwa kukhala 151.9 kcal / mole.Polymerization wa TFE kwambiri exothermic ndipo amapanga 41.12 kcal/mole heatd mlingo umene tingayerekeze ndi kutentha kwa polymerization wa vinilu kolorayidi ndi styrene, pa 23-26 kcal/mole ndi 16,7 kcal/mole, motero.
Kusungidwa kotetezedwa kwa TFE kumafuna kuti mpweya wake ukhale wochepera 20 ppm.Kutentha ndi kupanikizika ziyenera kuyendetsedwa panthawi yosungidwa.Kuwonjezeka kwa kutentha, makamaka pazovuta kwambiri, kungayambitse kutentha popanda mpweya (TFE imalowa mu carbon tetrafluoride).Pamaso pa mpweya kapena mpweya, TFE imapanga zosakaniza zophulika mu molar peresenti ya 14-43%.Kuphulika kwa chisakanizo cha TFE ndi okosijeni kungapangitse kupanikizika kwakukulu kwa 100 nthawi yoyamba.
Zinthu za Hexafluoropropylene
Hexafluoropropylene ndi mpweya wopanda mtundu, wopanda fungo, wosakoma, komanso wochepa kwambiri, womwe umatentha pa 29.4 C ndi kuzizira pa 156.2 C. Mu maola a 4, chiwerengero cha 3000 ppm chimafanana ndi LC50 mu makoswe.Kutentha kwakukulu ndi kupanikizika kwa HFP ndi 85 C ndi 3254 MPa.Mosiyana ndi TFE, HFP ndi yokhazikika kwambiri pokhudzana ndi autopolymerization ndipo ikhoza kusungidwa mumadzimadzi popanda kuwonjezera telogen.HFP imakhala yokhazikika mpaka 400e500 C. Pafupifupi 600 C pansi pa vacuum, imawola ndikupanga octafluoro-2-butene (CF3CF¼CFCF3) ndi octa-fluoroisobutylene.
Katundu wa Perfluoroalkyl Vinyl Ethers
Perfluoroalkyl vinilu ethers (PAVE) amapanga gulu lofunika la ma monomers chifukwa ndi ma comomers osankhidwa pa "kusintha" kwa katundu wa homofluoropolymers kuphatikiza kugwiritsa ntchito mozama mu kapangidwe ka ma copolymers a TFE.Ubwino wa ma PAVE monga osinthira pa HFP ndikukhazikika kwawo kwamafuta.Chitsanzo chofunikira pazamalonda ndi per-fluoropropyl vinyl ether (PPVE).PPVE ndi madzi osanunkhiza, opanda mtundu pa kutentha kwapakati.Imayaka kwambiri ndipo imayaka ndi lawi lopanda mtundu.Ndiwowopsa kwambiri kuposa HFP.
Makhalidwe a Chlorotrifluoroethylene
Chlorotrifluoroethylene ndi mpweya wopanda mtundu womwe umatentha kutentha komanso kupanikizika.Ndiwowopsa kwambiri ndi LC50 (khoswe) pakuwonetsa maola 4 komanso kuchuluka kwa 4000 ppm.Ili ndi kutentha kwakukulu ndi kupanikizika kwa 105.8 C ndi 4.03 MPa.CTFE ya okosijeni ndi yamadzimadzi imachita ndikupanga peroxides pa kutentha kwambiri.Zinthu zingapo zokhala ndi okosijeni, monga chlorodifluoroacetylfluoride, zimapangidwa ndi okosijeni wa CTFE.Chomwecho chingachitike photochemically mu nthunzi gawo.Chlorotrifluoroethylene oxide ndi zomwe zimachitika chifukwa cha izi.The peroxides amachita monga intiators kwa polymerization wa CTFE, amene akhoza kuchitika mwankhanza.
Makhalidwe a Vinylidene Fluoride
Vinylidene fluoride, (CH2¼CF2), imatha kuyaka [49] ndipo ndi mpweya wotentha kwambiri.Ndiwopanda mtundu ndipo pafupifupi alibe fungo ndipo amawira pa 84 C. VDF imatha kupanga zosakaniza zophulika ndi mpweya.Polymerization wa mpweya uwu ndi exothermic kwambiri ndipo umachitika pamwamba pa kutentha kwambiri ndi kupanikizika.
Makhalidwe a Vinyl Fluoride
Vinyl fluoride (75-02-5) (fluoroethene) ndi mpweya wopanda mtundu pamikhalidwe yozungulira.Imayaka mumlengalenga pakati pa malire a 2.6 ndi 22% ndi voliyumu.Kutentha kochepa koyatsira kwa VF ndi zosakaniza za mpweya ndi 400 C. Kuonjezera kuchuluka (<0.2%) kwa terpenes ndikothandiza kupewa polymerization ya VF yokha.VF yoletsedwa yadziwika kuti ndi gasi woyaka moto ndi dipatimenti ya zamayendedwe ku US.
Nthawi yotumiza: May-10-2018