Fluoropolymer inowanzove olefinic polymer iyo ine zvishoma kana zvizere fluorinated olefinic monomers akadai vinylidene fluoride (CH2¼CF2) uye tetrafluoroethylene (TFE) (CF2¼CF2).Aya mapolymer akafukidzwa zvakadzama mune akati wandei mareferensi.Mamwe mapolymer akasarudzika anosanganisira per-fluoroethers, fluoroacrylates, uye fluorosilicones ayo anoshandiswa mune vhoriyamu idiki zvakanyanya pane olefinic fluoropolymers.
Commercial fluoropolymers inosanganisira homopolymers uye copolymers.MaHomopolymers ane 99% kana kupfuura nehuremu hwemonomeri imwe uye 1% kana zvishoma nehuremu hweimwe monomer maererano negungano reAmerican Society for Testing Materials (ASTM).Copolymers ane zvinopfuura 1% kana kupfuura nehuremu hweimwe kana kupfuura comonomers.Iwo makuru ekutengesa fluoropolymers anobva pane matatu monomers:
TFE, vinylidene fluoride (VF2), uye kune zvishoma chlorotrifluoroethylene (CTFE).Mienzaniso yemakonomers anosanganisira perfluoromethyl vinyl ether (PMVE), perfluoroethyl vinyl ether (PEVE), perfluoropropyl vinyl ether (PPVE), hexafluoropropylene (HFP), CTFE, perfluorobutyl ethylene (PFBE), uye exotic monomers senge 2,2robistri- -4,5-difluoro-1,3-dioxole.
Mutemo wakanaka wekuyeuka ndewekuti kuwedzera fluorine zvirimo yepolymer molecule kunowedzera makemikari ayo uye zvinonyungudutsa kuramba, kuramba murazvo, uye photostability;inovandudza zvinhu zvayo zvemagetsi zvakadai sepasi dielectric constant;inoderedza coefficient of friction;inosimudza melting point;inowedzera kugadzikana kwayo kwekushisa;uye inonetesa maitiro ayo emagetsi.Solubility yemapolymers musolvents kazhinji inoderera nekuwedzera fluorine zvirimo mumorekuru.
Fluoropolymer Classification
Kuwanikwa kusinganzwisisike kwePTFE muna 1938 naRoy Plunkett weDuPont Company kwakatanga nguva yefluoropolymers.PTFE yakawana zviuru zvekushandisa nekuda kwezvimiro zvayo zvakasiyana.Yakasiyana-siyana fluoroplastics yakagadzirwa kubva pakuwanikwa kwePTFE.Makambani akati wandei anogadzira mapurasitiki aya pasi rose.Fluoropolymers yakakamurwa kuita makirasi maviri e perfluorinated uye chikamu fluorinated polymers.Perfluorinated fluoropolymers mahomopolymers uye copolymers eTFE.Mamwe emacomonomers anogona kunge aine hushoma hwezvinhu kunze kweC kana F.
Polymer Development Nhoroondo
PTFE haigone kugadzirwa nekunyunguduka-kugadziridza matekiniki nekuda kweiyo viscosity yakakwirira.Melt-processible fluoropolymers yakagadzirwa necopolymerization yeTFE.FEP, copolymer yeTFE neHFP, ine yakaderera yakanyanya kushandiswa kushandiswa kwekushisa kupfuura PTFE (200 C vs. 260 C) nekuda kwekuparara kwemaitiro emagetsi.PFA, copolymer yeTFE ine PPVE kana PEVE, inopa kugadzikana kwekushisa, kunyunguduka-kugadziriswa uye kushandiswa kwakanyanya kunoramba kuchipisa kutonhora 260 C. Zvose FEP nePFA zvinoonekwa seperfluoropolymers.
Copolymers ethylene ine tetrafluoroethylene (ETFE) uye chlorotrifluoroethylene (ECTFE) ine michina yakasimba kupfuura perfluoropolymers, inoperekedzwa netradeoffs yekuderedza kupikisa kwavo kwemakemikari uye kuenderera kwekushandisa tembiricha uye kuwedzera kweiyo coefficient of friction.
Amorphous copolymers eTFE anonyungudika mune akakosha halogenated solvents uye anogona kuiswa kune pamusoro sepolymer mhinduro kugadzira mapete matete.Iyo yakaomeswa yakaomeswa inoshingirira kune anenge akawanda makemikari sePTFE.
Nguva yekutumira: Jul-22-2017