Menene Fluoropolymer?

Fluoropolymer yawanci olefinic polymer wanda ya ƙunshi partially ko cikakken fluorinated olefinic monomers kamar vinylidene fluoride (CH2¼CF2) da tetrafluoroethylene (TFE) (CF2¼CF2).Wadannan polymers an rufe su daki-daki a cikin nassoshi da dama.Ƙarin ƙwararrun ƙwararrun polymers sun haɗa da per-fluoroethers, fluoroacrylates, da fluorosilicones waɗanda ake amfani da su a cikin ƙaramin ƙarami fiye da olefinic fluoropolymers.

Fluoropolymers na kasuwanci sun haɗa da homopolymers da copolymers.Homopolymers sun ƙunshi 99% ko fiye ta nauyi monomer ɗaya da 1% ko žasa da nauyin wani monomer bisa ga al'ada na Ƙungiyar Gwaji ta Amurka (ASTM).Copolymers sun ƙunshi fiye da 1% ko fiye da nauyin ɗaya ko fiye da masu haɗin gwiwa.Manyan fluoropolymers na kasuwanci sun dogara ne akan monomers guda uku:

TFE, vinylidene fluoride (VF2), kuma zuwa ƙarami chlorotrifluoroethylene (CTFE).Misalan comonomers sun haɗa da perfluoromethyl vinyl ether (PMVE), perfluoroethyl vinyl ether (PEVE), perfluoropropyl vinyl ether (PPVE), hexafluoropropylene (HFP), CTFE, perfluorobutyl ethylene (PFBE), da kuma monomers na musamman kamar 2,2-bistri-fluoromethyl. -4,5-difluoro-1,3-dioxole.

Kyakkyawan ƙa'idar babban yatsan yatsa don tunawa ita ce haɓaka abun ciki na fluorine na kwayoyin polymer yana ƙara ƙarfin sinadarai da juriya, juriya na harshen wuta, da kuma yanayin hoto;yana inganta halayen lantarki kamar ƙananan dielectric akai-akai;yana rage yawan adadin gogayya;yana tayar da narkewa;yana ƙara kwanciyar hankali na thermal;kuma yana raunana kayan aikin injiniyansa.Solubility na polymers a cikin kaushi yawanci yana raguwa ta ƙara abun ciki na fluorine na kwayoyin halitta.

Rarraba Fluoropolymer

Binciken da aka yi na PTFE a cikin 1938 ta Roy Plunkett na Kamfanin DuPont ya fara zamanin fluoropolymers.PTFE ya sami dubban aikace-aikace saboda musamman kaddarorin.An samar da nau'ikan fluoroplastics daban-daban tun lokacin da aka gano PTFE.Kamfanoni da yawa suna samar da waɗannan robobi a duniya.Fluoropolymers sun kasu kashi biyu na nau'ikan polymers masu baƙar fata da kuma wani ɓangare na fluorinated.Perfluorinated fluoropolymers su ne homopolymers da copolymers na TFE.Wasu daga cikin masu haɗin gwiwa na iya ƙunsar ƙaramin adadin abubuwa banda C ko F.

Tarihin Ci gaban polymer

Ba za a iya ƙirƙira PTFE ta dabarun sarrafa narke ba saboda babban danko.An ɓullo da narke-mai sarrafa fluoropolymers ta hanyar copolymerization na TFE.FEP, wani copolymer na TFE da HFP, yana da ƙananan matsakaicin zafin jiki na ci gaba da amfani fiye da PTFE (200 C vs. 260 C) saboda lalacewar kayan aikin injiniya.PFA, copolymer na TFE tare da PPVE ko PEVE, yana ba da kwanciyar hankali na thermal, narke-aiki da matsakaicin ci gaba da amfani da zafin jiki na 260 C. Dukansu FEP da PFA suna dauke da perfluoropolymers.

Copolymers na ethylene tare da tetrafluoroethylene (ETFE) da chlorotrifluoroethylene (ECTFE) sun fi ƙarfin injina fiye da perfluoropolymers, tare da raguwar juriya na sinadarai da ci gaba da amfani da zafin jiki da haɓaka ƙimar gogayya.

Amorphous copolymers na TFE suna narkewa a cikin abubuwan kaushi na halogenated na musamman kuma ana iya shafa su a saman a matsayin maganin polymer don samar da suturar bakin ciki.Busassun shafi yana da juriya ga kusan yawancin sinadarai kamar PTFE.