Ngaphakathi komhlaba wamapulasitiki kunezinhlobo ezahlukahlukene zokwenziwa kwezinto zokwenziwa. Enye yazo yi-PET (Poly Ethylene Terephthalate). Kungeqembu lama-polyesters futhi luhlobo lwezinto ezibonakalayo zepulasitiki ezisuselwa ku-petroleum. Abantu abaningi abazi yini i-PET. Kutholwe ososayensi baseBrithani uWininfield noDickson, ngo-1941, ababenelungelo lobunikazi njenge-polymer yokwenziwa kwemicu. Kuyasiza kakhulu namuhla.
Ngakho-ke, sizonikezela le ndatshana ukukutshela ukuthi yini i-PET, yiziphi izici zayo nokuthi yenzelwe ini.
Yini i-PET
Le nto inezici ezilandelayo, ezenze kwaba yinto ewusizo futhi enhle yokwakhiwa:
- Iyacutshungulwa ngokushaya, umjovo, ukukhishwa. Ifanele ukukhiqiza izimbiza, amabhodlela, amafilimu, amashidi, amapuleti nezingxenye.
- Ukubonisa ngale kanye nokucwebezela okunomthelela okhulisayo.
- Izici ezinhle kakhulu zomshini.
- Isithiyo segesi.
- I-biorientable-crystallizable.
- I-Sterilizable yi-gamma ne-ethylene oxide.
- Izindleko / ukusebenza.
- Kubekwe # 1 ekusetshenzisweni kabusha.
- Esilula
Okubi nokuhle
Njengazo zonke izinto zokwakha, kukhona nokubi okuthile kune-PET. Ukomisa kungenye yezinkinga zayo eziyinhloko. Yonke i-polyester kumele yomiswe ukuze kugwenywe ukulahleka kwezakhiwo. Umswakama we-polymer lapho ufaka inqubo kufanele ube ngaphezulu kuka-0.005%. Izindleko zemishini nazo ziyinkinga, njengokushisa. Imishini yokubumba ye-injection biologically oriented imele ukubuyiselwa okuhle okususelwa ekukhiqizweni. Ekubunjweni kwe-blow and extrusion, imishini ejwayelekile ye-PVC ingasetshenziswa, enokusebenziseka okungaphezulu kokukhiqiza osayizi abahlukahlukene nobubunjwa.
Lapho izinga lokushisa lidlula ama-degree angama-70, i-polyester ayikwazi ukugcina ukusebenza okuhle. Intuthuko yenziwe ngokuguqula imishini ukuvumela ukugcwaliswa okushisayo. I-Crystalline (opaque) i-PET inokumelana okuhle namazinga okushisa, kuze kufike ku-230 ° C. Akunconyelwe ukusetshenziswa unomphela kwangaphandle.
Manje sizohlaziya ukuthi ziyini izinzuzo zayo: sinezakhiwo ezihlukile, ukutholakala okuhle nokusetshenziswa kabusha okuhle. Phakathi kwezakhiwo zayo ezinhle sinokucaca, ukucwebezela, ukungafihli lutho, izakhiwo ezivimbela amagesi noma amaphunga, amandla omthelela, ukushisa komzimba, kulula ukuphrinta ngoyinki, uvumela ukupheka kwe-microwave.
Intengo ye-PET iguqukile ngaphansi kwamanye ama-polymer afana ne-PVC-PP-LDPE-GPPS kule minyaka engu-5 edlule. Namuhla, i-PET ikhiqizwa eNyakatho naseNingizimu Melika, eYurophu, e-Asia naseNingizimu Afrika. I-PET ingasetshenziswa kabusha ukuze ikhiqize into ebizwa nge-RPET. Ngeshwa, ngenxa yamazinga okushisa abandakanyekile kule nqubo, i-RPET ayinakusetshenziswa ukukhiqiza ukupakisha embonini yokudla.
Yiziphi izinto ezisebenzisa i-PET
Kunezinto ezahlukahlukene ezenziwe nge-polyethylene terephthalate noma i-PET. Okulandelayo ezinye izinto nezinto zokwenziwa ezenziwe ngale thermoplastic evuselelekayo:
- Iziqukathi zepulasitiki ezingavuselelwa kabusha. Ama-Thermoplastics asetshenziswa kakhulu ekukhiqizeni iziqukathi noma iziphuzo, njengeziphuzo ezibandayo namabhodlela amanzi. Ngenxa yobulukhuni nobulukhuni bayo, isibe yinto yokusetshenziswa kwansuku zonke emkhakheni wezimboni. Yize kuthinta nokuthi ingaphinde isetshenziswe ngokuphelele, kukalwa iqiniso lokuthi lisiza ukwenza amanye amabhodlela neziqukathi eziningi zepulasitiki.
- Izindwangu ezahlukahlukene. I-PET Luhlobo lweplastiki olusetshenziswa embonini yendwangu ukwenza izingubo ezehlukene. Eqinisweni, liyisikhundla esihle kakhulu selineni noma ukotini.
- Ifilimu noma ifilimu enezithombe. Le polymer epulasitiki nayo isetshenziselwa ukwenza amafilimu ahlukahlukene anezithombe. Yize, kuyasiza kakhulu ekwakheni iphepha eliyisisekelo le-X-ray.
- Umshini wenziwe. Namuhla, i-polyethylene terephthalate isetshenziselwa ukwenza imishini ehlukahlukene yokuthengisa nemishini ye-arcade.
- Amaphrojekthi wokukhanyisa. Isetshenziselwa ukwenza amalambu emiklamo ehlukene. Eqinisweni, i-PET ikhombisile ukuthi ingenye yezinto ezikhanga kakhulu ekwakhiweni kokukhanyisa, kungaba ngaphandle noma ngaphakathi.
- Ezinye izinto zokukhangisa. Isibonelo, amaphosta noma izimpawu zokuxhumana okubukwayo. Ngokufanayo, kuvame ukusetshenziswa njengezinto ezifanele ukwenziwa kwezikhangiso ezitolo nasemibonisweni ehlukahlukene yezohwebo noma imicimbi.
- Design obala kanye nezimo: Ngenxa yalezi zici ezimbili, abathengi bangabona ngaphakathi kokuthengayo futhi abakhiqizi banamathuba amaningi wokubonisa.
Ukupakisha kwe-PET okusimeme
Kunezizathu ezimbalwa eziyinhloko zokuthi kungani ukufakwa kwe-PET kubhekwa njengokuvikela imvelo kakhulu. Lezi izizathu:
Ukusetshenziswa okuphansi kwamandla nezinsizakusebenza zokwenza kwayo
Eminyakeni edlule, ukuthuthukiswa kobuchwepheshe kunciphise izinsizakusebenza ezidingekayo ekwakheni ukufakwa kwe-PET futhi ukusetshenziswa kwamandla kuhlelo lokukhiqiza kuncishisiwe. Ngaphezu kwalokho, ukuthwala kwayo kusho ukuthi izindleko nomthelela emvelweni kuzoncishiswa ngesikhathi sokuhamba, ngoba kuncane okuphezulu.
Ucwaningo oluningi luye lwabonisa nokuthi, uma kuqhathaniswa nezinye izinto zokwakha, ukufakwa kwe-PET kunciphisa okusemandleni ekhabhoni ngokukhiqiza imfucumfucu eqinile nokusetshenziswa kwamandla okuncane kwemishini yokukhiqiza.
Ukuvuselelwa okungcono
Ngokuvamile kukholakala ukuthi iziqukathi ze-PET zingavuselelwa kuphela amahlandla ambalwa, iqiniso ukuthi kuyinto engavuselelwa kabusha kuze kube nini nanini uma kwenziwa inqubo esebenzayo yokuphinda isebenze kabusha, kuya ngenhloso ezosetshenziswa.
Okwamanje, I-PET iyipulasitiki esetshenziswe kabusha kakhulu emhlabeniEqinisweni, eSpain, ama-44% okupakisha emakethe asetshenziselwa ukusetshenziswa kwesibili. Iphesenti kumele lenyuswe liye kuma-55% ngo-2025 ukuhambisana necebo lomnotho eliyindilinga okuvunyelwane ngalo yi-European Commission.
Ngaphezu kokusetshenziswa kabusha njengempahla yokudla, i-PET eyenziwe kabusha isetshenziswa nasembonini yezindwangu, yezimoto neyefenisha. Futhi inokuphepha kokusebenzisa iziqukathi ze-PET ezenziwe kabusha ekudleni naseziphuzweni. I-European Food Safety Agency iqinisekisile ukuthi iyinto ephephile, futhi isetshenziselwa ukuhweba nokusetshenziswa kwezinto zokusetshenziswa ngokususelwa ku-PET esetshenzisiwe kabusha etholwe emanzini naseziphuzweni ezithambile eSpain yiRoyal Decree 517/2013 igunyaza lokho Isitsha sokugcina kufanele okungenani siqukethe okungenani ama-50% e-PET eyintombi.
Ngakho-ke, singaphetha ngokuthi iziqukathi ze-PET ziphephile futhi zisimama emvelweni, hhayi kuphela ngenxa yamathuba abo amakhulu okusebenzisa kabusha, kodwa futhi nangenxa yokusebenza kwawo kahle kwamandla enqubeni yokukhiqiza. Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi mayelana nokuthi yini i-PET nezimpawu zayo.