Uyini umehluko phakathi kwe-PET ne-PETG?

I-PET, i-polycondensate, isetshenziswa kakhulu kumafilimu okupakisha ukudla kanye nemicu yendwangu, phakathi kwezinye izinhlelo zokusebenza. Manje isetshenziswa kakhulu njengezinto zokupakisha, hhayi emabhodleleni e-soda kuphela, kodwa futhi nasemathinini nasemapuletini e-PET (APET) angenasimo, amakristalu e-PET (CPET). Eminyakeni emihlanu edlule, ama-PET nama-copolyester ebanga lobunjiniyela, njengemikhiqizo emisha ye-polymer, asetshenziswe ezintweni zokupakisha zobunjiniyela kanye nezobuchwepheshe, ngokulandelana.
Impumelelo ye-PET ekupakisheni i-soda ibangelwa ukuqina kwayo nokucaca kwayo, amakhono okuqondisa, inani elihle kakhulu kwezomnotho, kanye nokuthuthukiswa kobuchwepheshe bokucubungula amabhodlela ngesivinini esikhulu. Amathini eziphuzo e-PET alula, awaphuki, angasetshenziswa kabusha, futhi anomoya omuhle. Ibhodlela leziphuzo le-PET eligcwele amalitha ama-2 lilula ngo-24% kunebhodlela lengilazi elifanayo; ibhodlela elingenalutho linesisindo esingu-1/10 sebhodlela lengilazi elinobukhulu obufanayo. Lokhu kusindisa umsebenzi, amandla, kanye nezindleko kuzo zonke izixhumanisi ezivela kumkhiqizi kuya kumthengi.
I-Chemistry kanye Nezakhiwo

I-PET yamabhodlela okuphuza ikhiqizwa nge-terephthalic acid (TPA) etholakala nge-oxidation ye-p-xylene. I-Terephthalic acid iyahlanzwa noma ixutshwe ne-methanol ukuze yakhe i-dimethyl terephthalate (DMT), noma ixutshwe futhi ukuze yakhe i-terephthalic acid emsulwa (PTA). Enye into eluhlaza eyisisekelo ye-PET yi-ethane, eguqulwa ibe yi-ethylene glycol (EG) ngokusabela. I-PET iyi-polymer yokujiya eyakhiwe yi-polymerization eqhubekayo ye-DMT (noma i-PTA) kanye ne-EG esimweni esincibilikisiwe, bese kuba yinqubo ye-polymerization yesimo esiqinile ukuthola amakristalu amakhulu kanye nesisindo sokugcina sama-molecule kanye ne-viscosity yangaphakathi. Inqubo yesimo esiqinile yenza futhi okuqukethwe kwe-ethanol kwe-polymer kube phansi ngokwanele.

I-resin ye-PET evamile yezentengiselwano iyancibilika cishe ku-480F (), kodwa iphuzu lokuncibilika kwe-PET enekristalu ephezulu lingaba ngu-520F ().

I-PET eqinisiwe eqondiswe kahle inamandla amahle kakhulu. Iqinile futhi icacile, futhi imelana nama-asidi abuthakathaka, izisekelo kanye nezincibilikisi eziningi.

Amabanga akhethekile

I-PET yezinga lokubumba elithambile inganikeza umbala oqinile, oluhlaza okotshani kanye nophuzi okhanyayo. I-polymer enemibala e-reactor ayidingi ukuhlanganiswa nemiphumela emibi ezimpahleni zomzimba, futhi ithuthukisa ukufana kombala. Ama-resin amsulwa ane-viscosities ehlukahlukene ayatholakala. Ama-copolymer e-PET abumba kancane kancane, okuwavumela ukuthi akhiqize amabhodlela e-soda asezingeni eliphezulu ezimweni eziningi zokucubungula. I-polymer ebumbekayo ye-extrusion blow nayo iyatholakala. Lokhu kuhlanganiswa kuhlanganisa izinzuzo zamandla amahle okuncibilika kanye ne-crystallization ehamba kancane, futhi kungacutshungulwa kalula emishinini efanele ye-extrusion blow molding. Ama-polymer ahlukahlukene aqinisiwe, avimbela ilangabi kanye namanye akhethekile ahlala ethulwa noma eguqulwa ukuze ahlangabezane nezinhlelo zokusebenza ezintsha.

I-PETGI-copolyester ingenye isibonelo senani elikhulu lama-copolyester. Ngokungafani ne-PCTA, eguqulwa nge-asidi, i-PETG iyi-polymer eguqulwe nge-diol eyenziwe ngokuhlanganisa i-CHDM diol ne-TPA (terephthalic acid) kanye ne-ethylene glycol. Ama-copolymer e-PETG angabunjwa noma akhishwe futhi ngokuvamile ahlale engaguquki, esobala futhi engenambala, ngisho nasezigabeni ezinkulu.

Inokuqina okuphezulu, ubulukhuni kanye nokuqina okuhle, ngisho noma amazinga okushisa aphansi. Inhlanganisela yokucaca, ukuqina kanye namandla okuncibilika yenza kube usizo ekubumbeni ngomjovo, ekubumbeni ngokuqhumisa kanye nokukhipha amaphrofayili, amapayipi, amafilimu namashidi. I-PETG itholakala ngesimo esingashintshiwe noma ngezithasiselo ezahlukahlukene, kufaka phakathi ama-release agents, ama-masterbatches, kanye nama-impact modifiers okubumba ngomjovo.

I-PETG kufanele yomiswe ku-120-160F cishe amahora angu-4-6 ngaphambi kokubumba noma ukukhipha. Kuzo zombili izinqubo, izinga lokushisa lokuncibilika lisukela ku-420F kuya ku-510F. Isikhathi sokubamba imishini yokucubungula emazingeni okushisa aphezulu kufanele sibe sifushane ngangokunokwenzeka ukuvimbela ukuwohloka ngokweqile. Ukubumba ngomjovo kufanele kwenziwe emshinini wokubumba ngomjovo, okudinga ukuthi isibhamu ngasinye sibe ngu-50% kuya ku-80% wamandla aso.

I-PETG ingakhishwa futhi ibunjwe ngomshini wokushisa oncibilikisiwe phakathi kuka-400-450F ukuze kwenziwe amabhodlela abonakalayo e-shampoo, insipho yoketshezi, imikhiqizo yokuhlanzeka, amafutha amaminerali, kanye nokupakishwa kokudla. Lokhu kwaziswa kuhlangabezana nezindinganiso ze-FDA zokuthintana nokudla.

Ukukhipha kungakhiqiza izinhlobo eziningi zamaphrofayili, kanye namashubhu okupakisha, amafilimu, namashidi, okuhlanganisa nokupakisha amadivayisi ezokwelapha. I-PETG ne-PCTA zingahlanzwa nge-ethylene oxide kanye nemisebe ye-Y.

Uma isetshenziselwa ukubumba ngomjovo, i-PETG ivame ukucutshungulwa ebangeni lokushisa lokuncibilika elingu-450-510F, kanye nokushisa kwesikhunta okungaba ngu-70-130F. Izicelo zamanje zifaka izembozo zezinsimbi, izihlangu zomshini, izitsha zokuhlobisa, izikhombisi zedivayisi ye-lever, izingxenye zokubonisa kanye namathoyizi.

I-PET isetshenziswa kakhulu ekupakisheni i-soda neziphuzo ezibandayo. I-PET cishe inemakethe yezitsha ezingaphinde zisetshenziswe ezingamalitha amabili, kanti amabhodlela e-PET angu-1.5-litre, 1-litre, 0.5-litre kanye namancane nawo aqashelwa kabanzi.

I-PET isetshenziswa ekudleni, utshwala, ezinhlotsheni zokuhlanzisisa. Kulindeleke ukuthi isidingo se-PET siqhubeke nokukhula kweziphuzo ezingena-carbon kanye nokupakishwa kwemikhiqizo yezimboni. Ukudla okupakishiwe kuhlanganisa i-mustard, imikhiqizo yerabha, ibhotela lamantongomane, izinongo, amafutha okupheka, ama-cocktail kanye namajusi agxilile. Imibala emisha, ikakhulukazi imibala ye-Weber, ithandwa kakhulu ekupakishweni kwemithi, amavithamini kanye nezinhlonzi.

Enye yezinhlelo zokusebenza ezintsha nezikhula ngokushesha zezitsha ze-PET ukupakishwa kokudla noma kweziphuzo, okudinga ukugcwaliswa emazingeni okushisa aphezulu. Ukudla okuningi, ikakhulukazi izithelo noma ukudla noma iziphuzo ezinokuqukethwe okuphezulu kwezithelo, kumele kupakishwe ku-180F noma ngaphezulu. Lokhu kunikeza ukuhlanza (ukubulala amagciwane) komkhiqizo kanye nesitsha ngesikhathi sokugcwalisa. Izitsha ezijwayelekile, njengezikhwama zesoda neziphuzo ezibandayo, zivame ukushwabana futhi ziguge lapho zifakwa emazingeni okushisa angaphezu kuka-160F, okubangelwa ukuphumula kokucindezeleka okuthile. Ukuhlushwa kokucindezeleka kukhiqizwa ngesikhathi sokubumba kwe-stretch blow kwesitsha. Ubuchwepheshe buthuthukiswe ukuthuthukisa ukumelana nokushisa ngesikhathi sokucubungula, okuvame ukubizwa ngokuthi ubuchwepheshe "bokubeka ukushisa". Kuye ngobuchwepheshe obuthile bokucubungula, kunemininingwane eminingana yobuchwepheshe bokucubungula, enelungelo elikhulu, ngokusekelwe ekutheni yiziphi izitsha ezifanele ukugcwaliswa ku-190-195F ezingakhiqizwa. Imikhiqizo edinga ukupakishwa ngalesi sici ifaka phakathi amajusi ezithelo ahlanzekile. Iziphuzo ezinamajusi amaningi, itiye, iziphuzo ezithile ze-isotonic nezemidlalo, izinongo, amajusi agxilile kanye namanzi athile amaminerali.

Okunye ukusetshenziswa kwe-PET kusetshenziswa kabanzi ekumbozeni i-extrusion kanye nefilimu neshidi le-extrusion. I-PET isetshenziswa njengento yokumboza i-extrusion yokupakisha ibhodi lephepha elifakwa kuhhavini. Ngaphezu kwalokho, i-crystalline PET (CPET) ingasetshenziswa njengento eyisisekelo yokwenza amathreyi ehhavini.

Ifilimu ye-PET ivame ukuqondiswa eceleni kwezinhlangothi ezimbili futhi isetshenziswa njenge-X-ray kanye namanye amafilimu ezithombe, ukupakisha inyama noshizi, amateyipu kazibuthe, ukufakelwa kukagesi, amapuleti okunyathelisa kanye nezikhwama zokupakisha amabhodlela. I-PET isetshenziswa futhi njengezinto zetheyiphu yezimboni. Ifilimu neshidi le-PET elingakhiqizi ikristalu, elingaqondisiwe liqala ukusetshenziselwa ukwakha izitsha, amathileyi, imikhiqizo ye-foam kanye nezinkomishi zeziphuzo.

Isifinyezo: I-PETG inguqulo ethuthukisiwe ye-PET, enokucaca okuphezulu, ukuqina okuphezulu, ukumelana okungcono komthelela, futhi-ke intengo ephezulu.