Uma i-polymer isincibilikisiwe, yaxutshwa futhi yacindezelwa ku-extruder, iphonswa nge-extrusion die ukuze yakheke ngokuqhubekayo (emva kokupholisa nokuqiniswa) ibe umkhiqizo wokugcina.Izinhlobo ezivame kakhulu zokufa yi-flat, annular kanye ne-proŽle.Imikhiqizo eyenziwe nge-extrusion ihlanganisa ipayipi, ishubhu, ukunamathela ngocingo, amabhodlela epulasitiki, amafilimu epulasitiki namashidi, izikhwama zepulasitiki, okokunamathisela kwephepha ne-foil, ama-Ž bres, i-Ž laments, intambo, amateyipu kanye nohlu olubanzi lwamaphrofayili.
I-polymer extrusion through dies inokufana okuthile nokukhipha okushisayo kwezinsimbi.Nokho, kukhona futhi umehluko obalulekile.Ku-extrusion yensimbi impahla iphushelwa phambili ngenqama, kuyilapho ku-polymer extrusion i-material ihlinzekwa ngokuqhubekayo ngesikulufu esijikelezayo.Ku-extrusion yensimbi eshisayo amazinga okushisa asukela ku-340°C ku-magnesium kuya ku-1325°C ngensimbi, futhi izingcindezi ezihambisanayo zisukela ku-35 kuya ngaphezu kuka-700 MPa.1 5 Ku-polymer extrusion amazinga okushisa awavamile ukwedlula ku-350°C, futhi izingcindezi ngokuvamile azivamile. hamba kakhulu ngaphezu kwama-MPa angama-50 endaweni yesikulufu.I-solid phase extrusion yama-polymers yenzelwe ukukhiqizwa kwemikhiqizo ethile yamandla aphezulu.Emazingeni okushisa aphansi, i-molecular orientation enikezwa ukuphoqelelwa kwezinto ngokusebenzisa ukufa kokubunjwa kuhlala ku-extrudate.I-solid state polymer extrusion inokufana okuthile ne-extrusion ebandayo yezinsimbi.
I-Blown film extrusion iyinqubo ebaluleke kakhulu ekukhiqizweni kwefilimu yepulasitiki ezacile evela ku-polyethylenes.I-polymer encibilikisiwe ikhishwa nge-annular die (imvamisa yokwakhiwa kwe-spiral mandrel) ukuze yakhe ishubhu elincanyana elibiyelwe kanye kanye elidonswa nge-axially futhi linwetshwe ngemisebe.Ezimweni eziningi ibhamuza lefilimu eliphephukayo lakheka libheke phezulu.Ubukhulu bebhamuza ububanzi buvamise ukuba 1.2 – 4 izikhathi ezinkulu kunobubanzi bokufa.Ukuncibilika okushisayo kupholiswa imifudlana ye-annular yomoya wesivinini esikhulu ovela emasongweni omoya angaphandle, futhi ngezikhathi ezithile nakwabasabalalisi bomoya bangaphakathi.I-solidiŽ ed Žfilm idlula ohlakeni olumpintsha phezulu kwebhamuza bese ithathwa ngama-roller.Amafilimu ahlanganisiwe anezendlalelo ezi-3 – 8 (ngezinye izikhathi aze afike ku-11) nawo akhiqizwa yile nqubo, ukuze asetshenziswe ekufakweni kokudla.
I-Cast Žfilm ne-extrusion yeshidi ihlanganisa ukukhipha ipholymer endaweni enembobo ebanzi (kufika ku-10 m), kurola wensimbi epholile noma amarola acisha futhi aqinise into encibilikisiwe.Ifilimu ngokuvamile ichazwa njengomkhiqizo ozacile kuno-0.25 mm, kanti ishidi lijiyile kunalokhu.Inqubo ye-Žfilm ye-cast isetshenziselwa ukubekezelela okuqinile kwefilimu e-thinŽ, noma ama-resin e-viscosity aphansi.Amafa amaningi ayisicaba amadizayini we-T slot noma ama-coathanger, aqukethe ukuphindaphindeka kokusabalalisa i-polymer egelezayo yonkana ububanzi befasi, kulandelwa ezansi nomfula ngokushintshanisa izimbotshana eziwumngcingo nezivulekile ukuze kudalwe ukusatshalaliswa kokugeleza okufunayo nokwehla kwengcindezi.Olayini abaningi bamafilimu abalingiswa abakhiqizwe namuhla yilayini ehlangene, ehlanganisa izendlalelo kusuka kuma-extruder ayisikhombisa ukuya emkhiqizweni ngokufa okuhlukahlukene, noma ukufa okukodwa ngosizo lwama-feedblocks.
Ku-Žfilm extrusion, amazinga okugunda ezindebeni ze-die ngokuvamile angu-~103 s21.Uma ukucindezelwa kwe-shear odongeni kudlula inani elithile (imvamisa i-0.14 MPa emaphepheni ocwaningo, ephakeme embonini ngosizo lwezithasiselo), indawo ye-extrudate ilahlekelwa ukucwebezela kwayo ngenxa yesenzakalo sokuqhekeka kwe-sharkskin. kubonakala ngeso lenyama, i-perpendicular to flow direction.
Ipayipi neshubhu extrusion kubandakanya ukumpompa i-polymer encibilikisiwe ngokusebenzisanannulardie, okulandela ukuthi umkhiqizo okhishiwe, ngenkathi udonswa, udlule kusayizi we-vacuum lapho ufinyelela ubukhulu bawo bokugcina.Lokhu kulandelwa ukupholisa isifutho noma ukucwiliswa nokusikwa ngobude obungashintshi.Ipayipi lobubanzi obufika ku-2 m noma ngaphezulu lenziwa yile nqubo, futhi ishubhu enobubanzi obusuka ku-10 mm yehle iye ngaphansi kwe-1 mm.I-annular efa ngokuvamile i-spider noma i-spiral mandrel design.
Ezinqubweni zokuhlanganisa izintambo nezintambo, izintambo ezingazodwana noma izintambo ezihlanganisiwe zidonswa ngesivinini esikhulu ngokusebenzisa i-crosshead die, kuma-engeli angakwesokudla ku-eksisi ye-extruder.Ku-extrusion yomfutho ophezulu, i-polymer encibilika ihlangana nentambo noma ikhebula ngaphambi kokuphuma kwe-die, isibonelo ukuvaleka kwezintambo ezingazodwana.Ku-extrusion ye-low pressure, inyibiliki ihlangana nekhebuli ngemva kokuphuma kwefa, isibonelo ukufakwa kwejakhethi kwamakhebula agqunyiwe.Amazinga aphezulu kakhulu okugunda avame ukuhlangana nawo kule nqubo (kufika ku-106 s2 1) kanye nezinsalela ze-viscosity eziphansi ziyasetshenziswa.
I-ProŽfile extrusion iyinqubo yokukhiqiza esetshenziselwa imikhiqizo ephambana njalo.Lokhu kungasukela kumomo olula kuye kumaphrofayili ayinkimbinkimbi anamagumbi amaningi kanye neminwe ye-Ž.Izibonelo ukusuka ekubunjweni kwefreyimu yesithombe, ukuya ekusikeni kwezimoto, ukuya ekuphetheni kwamatop tablet, kuya emigqeni yamawindi.Izinto ezikhishiwe zihlukaniswa (cishe) njengeziqinile noma ezingabekeki.Ulayini ojwayelekile we-proŽle we-extrusion uqukethe i-extruder empompa i-polymer nge-proŽle die, elandelwa ithangi lokulinganisa noma i-calibrator, imikhumbi yokupholisa eyengeziwe, idonsa kanye nedivaysi yokusika.Idizayini yephrofayili iyafa idinga ulwazi olunzulu nokubekezela.Imikhawulo yokuphuma kwephrofayili kuhlangatshezwana nayo ngenxa yesikhumba sikashaka (emikhiqizweni emincane ekhiqizwe ngama-polymers ane-viscosity ephezulu) noma ikhono lokupholisa imikhiqizo ewugqinsi enezindonga.Ipayipi le-polymer kanye ne-proŽfile extrusion kufana nokukhipha okushisayo kwezinsimbi ukuze kukhiqizwe izimo ezingenalutho eziqhubekayo zezinto ezinjenge-bar.Kodwa-ke, imodeli yezibalo yalezi zinqubo zensimbi isekelwe ikakhulukazi ekuqageleni kokugeleza kwepulasitiki.
Ekuphotheni okuncibilikayo, i-polymer encibilikisiwe idlula kuma-capillary amaningi ku-spinneret (kufika ku-1000).I-polymer ilethwa ngaphansi kwengcindezi yiphampu yegiya ukuze kulinganiswe kahle imitha, ngemva kokudlula ku-Ž lter elandela i-extruder.Lapho iphuma kuma-capillaries, i-Ž ikhala iyancipha ibe ububanzi obudingekayo. Ukuze kukhiqizwe ama-Žfibres amancane kakhulu, inqubo yokuncibilika iyasetshenziswa.Kule nqubo ama-Ž bres ancishiswa amandla okudonsa asetshenziswa indiza yomoya enesivinini esikhulu.
Isikhathi sokuthumela: Apr-19-2017