Ukudla okuqandisiwe kubhekise ekudleni lapho izinto ezingavuthiwe zokudla zicutshungulwa kahle, ziqandiswe ezingeni lokushisa elingu-30℃, futhi zigcinwe futhi zisakazwe ku-18℃ noma ngaphansi ngemva kokupakishwa.Ngenxa yokusetshenziswa kwezinga lokushisa eliphansi lokugcina iketango elibandayo kuyo yonke inqubo, ukudla okuqandisiwe kunezici zokuphila kweshalofu ende, akulula ukonakala futhi kulula ukukudla, kodwa futhi kubeka phambili izinselele ezinkulu kanye nezidingo eziphakeme zezinto zokupakisha.
Izinto ezivamile zokupakisha ukudla okuqandisiwe
Okwamanje, evamileizikhwama zokudla eziqandisiweemakethe ngokuvamile zisebenzisa ukwakheka okulandelayo:
1.PET/PE
Lesi sakhiwo sivamile uma kuqhathaniswa nokupakishwa kokudla okufriziwe okusheshayo, umswakama-ubufakazi, ukumelana nokubanda, izinga lokushisa eliphansi lokubeka uphawu lokushisa kuhle, izindleko ziphansi kakhulu.
2. I-BOPP/PE, BOPP/CPP
Lolu hlobo lwesakhiwo alukwazi ukumelana nomswakama, alukwazi ukumelana nokubanda, futhi lunamandla amakhulu okubamba ukushisa okuphansi kwezinga lokushisa eliphansi, okwenza lungabizi kakhulu.Phakathi kwazo, izikhwama zokupakisha zesakhiwo se-BOPP/PE zinokubukeka okungcono nokuzizwa kunesakhiwo se-PET/PE, esingathuthukisa ibanga lomkhiqizo.
3. I-PET/VMPET/CPE, BOPP/VMPET/CPE
Ngenxa yokuba khona kwe-aluminium enamathelayo, lolu hlobo lwesakhiwo lunendawo ephrintiwe kahle, kodwa ukusebenza kwalo kokuvalwa kwezinga lokushisa eliphansi kubi kancane futhi izindleko zalo ziphezulu uma kuqhathaniswa, okuholela ekusetshenzisweni kwezinga eliphansi uma kuqhathaniswa.
4. NY/PE, PET/NY/LLDPE, PET/NY/AL/PE, NY/PE
Ukupakishwa kwalolu hlobo lwesakhiwo amelana neqhwa kanye nomthelela.Ngenxa yokuba khona kongqimba lwe-NY, inokumelana nokubhoboza okuhle, kepha izindleko ziphakeme kakhulu.Ngokuvamile isetshenziselwa ukupakisha imikhiqizo enemiphetho noma izisindo ezinzima.
Ngaphezu kwalokho, kunolunye uhlobo lwesikhwama se-PE esivame ukusetshenziswa njengesikhwama sokupakisha sangaphandle semifino kanye nokudla okufriziwe okupakishwe.
In Ngaphezu kwalokho, kunesikhwama se-PE esilula, esivame ukusetshenziswa njengemifino, izikhwama ezilula eziqandisiwe zokupakisha ukudla, njll.
Ngaphezu kwezikhwama zokupakisha, okunye ukudla okuqandisiwe kudinga ukusebenzisa ithreyi lepulasitiki, impahla yethreyi evame ukusetshenziswa kakhulu yi-PP, inhlanzeko ye-PP yebanga lokudla yinhle, ingasetshenziswa ekushiseni okunga-30 ℃, kune-PET nezinye izinto.Ibhokisi likathayela njengepakethe evamile yezinto zokuhamba, ukumelana nokushaqeka kwalo, ukumelana nengcindezi kanye nezinzuzo zezindleko, kuwukucatshangelwa kokuqala kwezinto zokupakisha zokuthutha eziqandisiwe.
Izinkinga ezimbili ezinkulu azinakuzitshwa
1. ukudla okomile ukusetshenziswa, okokuqandisa isenzakalo esivuthayo
Isitoreji esiqandisiwe singanciphisa kakhulu ukukhula nokukhiqizwa kabusha kwama-microorganisms, kunciphise izinga lokubola nokonakala kokudla.Kodwa-ke, ezinqubweni ezithile zokugcina eziqandisiwe, izimo zokomisa kanye ne-oxidation zokudla nazo zizoba nzima kakhulu ngokwandiswa kwesikhathi sokuqandisa.
Efrijini, kukhona ukusabalalisa kwezinga lokushisa kanye nomusi wamanzi ukucindezela ingxenye: indawo yokudla>umoya ozungezile>opholile.Ngakolunye uhlangothi, lokhu kungenxa yokuthi ukushisa okungaphezulu kokudla kudluliselwa emoyeni ozungezile, kuqhubeke kunciphisa izinga lokushisa;Ngakolunye uhlangothi, ukucindezelwa okuhlukile komhwamuko phakathi kwendawo yokudla nomoya ozungezile kungakhuthaza ukuhwamuka nokuncishiswa kwamanzi namakristalu eqhwa endaweni yokudla emoyeni.
Kuleli qophelo, umoya oqukethe umhwamuko omningi wamanzi ubamba ukushisa, unciphise ukuminyana kwawo, futhi uya emoyeni ngaphezu kwesiqandisi;Lapho ugeleza endaweni epholile, ngenxa yezinga lokushisa eliphansi kakhulu lepholile, umfutho wamanzi agcwele kulelo zinga lokushisa nawo uphansi kakhulu.Njengoba umoya upholiswa, umhwamuko wamanzi uthinta indawo epholile bese ujiya ube isithwathwa, okwandisa ukuminyana komoya opholile kanye nokuzika bese kuhlangana nokudla futhi.Le nqubo izoqhubeka iphindaphinda futhi ijikeleze, futhi amanzi ebusweni bokudla azoqhubeka elahlekile, okuholela ekunciphiseni kwesisindo.Lesi simo sibizwa ngokuthi "ukusetshenziswa okomile".
Phakathi nenqubo eqhubekayo yokomisa isenzakalo, ingaphezulu lokudla liyoba kancane kancane libe izicubu ezinama-porous, okwandisa indawo yokuxhumana nomoya-mpilo, kusheshiswe i-oxidation yamafutha okudla kanye ne-pigments, okwenza kube nsundu ebusweni kanye nokuguqulwa kwamaprotheni.Lesi simo saziwa ngokuthi "ukushiswa okuqandisiwe".
Ngenxa yokudluliselwa komhwamuko wamanzi kanye nokusabela kwe-oxidation komoya-mpilo emoyeni, okuyizizathu ezibalulekile zalezi zenzakalo ezingenhla, izinto zokupakisha zepulasitiki ezisetshenziswa ekupakishweni kwangaphakathi kokudla okuqandisiwe kufanele zibe nomhwamuko omuhle wamanzi kanye nezindawo zokuvimbela umoya-mpilo njenge umgoqo phakathi kokudla okuqandisiwe nomhlaba wangaphandle.
2. Umthelela Wendawo Yesitoreji Eqandisiwe Emandleni Emishini Yezinto Zokupakisha
Njengoba kwaziwa, amapulasitiki aba brittle futhi athambekele ekuqhekekeni lapho evezwe emazingeni okushisa aphansi isikhathi eside, okuholela ekwehleni okukhulu kwezakhiwo zomzimba.Lokhu kukhombisa ubuthakathaka bezinto zepulasitiki ekuphikisweni okubandayo okubandayo.Ngokuvamile, ukumelana okubandayo kwamapulasitiki kuboniswa ukushisa kwe-embrittlement.Njengoba izinga lokushisa lincipha, amapulasitiki aba brittle futhi athambekele ekuqhekekeni ngenxa yokuncipha komsebenzi wamaketanga awo e-polymer molecular.Ngaphansi kwamandla omthelela ashiwo, ama-50% amapulasitiki ahluleka ukuphuka, futhi lokhu kushisa kuyizinga lokushisa eliqinile, okuwumkhawulo ophansi wezinga lokushisa lapho izinto zepulasitiki zingasetshenziswa ngokujwayelekile.Uma izinto zokupakisha ezisetshenziselwa ukudla okuqandisiwe zikwazi ukumelana nokubanda okubi, ama-protrusions abukhali wokudla okuqandisiwe angabhoboza kalula iphakheji ngesikhathi sokuhamba ngokuhamba kwesikhathi nokulayisha nokuthulula, okubangela izinkinga zokuvuza futhi kusheshise ukonakala kokudla.
Izixazululo
Ukunciphisa imvamisa yezinkinga ezimbili ezinkulu ezishiwo ngenhla nokuqinisekisa ukuphepha kokudla okuqandisiwe, izici ezilandelayo zingacatshangelwa.
1. Khetha umgoqo ophezulu kanye nezinto zokupakisha zangaphakathi eziqinile
Kunezinhlobonhlobo zezinto zokupakisha ezinezakhiwo ezahlukahlukene.Kuphela ngokuqonda izici ezibonakalayo zezinto ezihlukahlukene zokupakisha lapho singakhetha khona izinto ezisetshenziswayo ezinengqondo ngokusekelwe ezimfuneko zokuvikela zokudla okuqandisiwe, ukuze zikwazi ukugcina ukunambitheka nekhwalithi yokudla futhi zibonise inani lomkhiqizo.
Okwamanje,ipulasitiki eguquguqukayo emaphaketheniesetshenziswa emkhakheni ukudla eqandisiwe ihlukaniswe ikakhulukazi izigaba ezintathu:
Uhlobo lokuqala luwungqimba olulodwaizikhwama zokupakisha, njengezikhwama ze-PE, ezinomphumela ongemuhle wesithiyo futhi ezivame ukusetshenziselwaukupakishwa kwemifino, njll;
Uhlobo lwesibili izikhwama zokupakisha zepulasitiki ezithambile eziyinhlanganisela, ezisebenzisa izinto zokunamathisela ukuze zibophe izingqimba ezimbili noma ngaphezulu zezinto zefilimu yepulasitiki ndawonye, njenge-OPP/LLDPE, NY/LLDPE, njll., enokumelana nomswakama kahle, ukumelana nokubanda, nokumelana nokubhoboza. ;
Uhlobo lwesithathu izikhwama zokufaka zepulasitiki ezithambile ezinezingqimba eziningi, ezincibilikisa futhi zikhiphe izinto ezisetshenziswayo ezihlukile ezifana ne-PA, PE, PP, PET, EVOH, njll., futhi zizihlanganise kufayini eyinhloko.Zifuthwa, zinwetshwe, futhi zipholiswe ndawonye.Lolu hlobo lwempahla alusebenzisi izinto zokunamathisela, futhi lunezici zokungangcoli, umgoqo ophezulu, amandla aphezulu, nokumelana nokushisa okuphezulu nokuphansi.
Imininingwane ikhombisa ukuthi emazweni athuthukile nasezifundeni, ukusetshenziswa kohlobo lwesithathu lokupakisha kubalelwa ku-40% wesamba sokupakishwa kokudla okuqandisiwe, kanti e-China kubalwa cishe u-6%, odinga ukukhushulwa okwengeziwe.
Ngokuqhubeka okuqhubekayo kobuchwepheshe, izinto ezintsha nazo ziyavela ngokulandelana, futhi ifilimu yokupakisha edliwayo ingomunye wabameleli.Isebenzisa ama-polysaccharides, amaprotheni, noma i-lipids e-biodegradable njenge-substrate, futhi yakha ifilimu evikelayo ebusweni bokudla okuqandisiwe ngokugoqa, ukucwiliswa, ukumboza, noma ukufafaza, kusetshenziswa izinto ezidliwayo zemvelo njengezinto zokusetshenziswa kanye nokusebenzisana kwe-intermolecular ukulawula ukudluliswa kwamanzi kanye ukungena kwe-oxygen.Le filimu inokumelana namanzi okusobala kanye nokumelana nokuqina kwegesi okunamandla.Okubaluleke kakhulu, ingadliwa ngokudla okufriziwe ngaphandle kokungcoliswa futhi inamathemba abanzi okusebenza.
2. Ukuthuthukisa ukumelana nokubanda namandla emishini yezinto zokupakisha zangaphakathi
Indlela 1:Khetha izinto ezisetshenziswayo eziyinhlanganisela ezifanele noma ezikhishwe ngokuhlanganyela.
Inayiloni, i-LLDPE, ne-EVA zonke zinokumelana nezinga lokushisa eliphansi kakhulu, ukumelana nezinyembezi, kanye nokumelana nomthelela.Ukwengeza izinto ezinjalo zokusetshenziswa ezinqubweni eziyinhlanganisela noma ze-co extrusion kungathuthukisa ngempumelelo ukungangeni kwamanzi, ukuvimbela igesi, namandla emishini yezinto zokupakisha.
Indlela 2:Khulisa ingxenye yama-plasticizers ngendlela efanele.
Ama-Plasticizer asetshenziswa kakhulu ukwenza buthaka izibopho zesibili phakathi kwama-molecule e-polymer, ngaleyo ndlela andise ukuhamba kwamaketanga e-polymer yamangqamuzana futhi kuncishiswe ubukristalu.Lokhu kubonakala ngokuncipha kokuqina, i-modulus, kanye nezinga lokushisa le-polymer, kanye nokwenyuka kobude nokuguquguquka.
Qinisa imizamo yokuhlola ukupakisha
Ukupakisha kubaluleke kakhulu ekudleni okuqandisiwe.Ngakho-ke, izwe lenze amazinga afanelekile kanye nemithethonqubo efana ne-SN/T0715-1997 "Imithetho Yokuhlola Yokupakishwa Kwezokuthutha Zemikhiqizo Eqandisiwe Yokudla Ethunyelwa Ngaphandle".Ngokusetha izimfuneko eziyisisekelo zokusebenza kwempahla yokupakisha, ikhwalithi yayo yonke inqubo kusukela ekupakishweni kwempahla eluhlaza, ubuchwepheshe bokupakisha kuya kumphumela wokupakisha iqinisekisiwe.Mayelana nalokhu, amabhizinisi kufanele asungule ilabhorethri ebanzi yokulawula ikhwalithi yokupakisha, efakwe igumbi elihlanganisiwe lesakhiwo se-oksijini/umhwamuko wamanzi, umshini ohlakaniphile wokuhlola i-electronic tensile, umshini wokuminyanisa amakhadibhodi nezinye izinsimbi zokuhlola, ukuze kwenziwe uchungechunge lokuhlola izinto zokupakisha ezifriziwe, okuhlanganisa ukusebenza kwesithiyo, ukusebenza ngokucindezela, ukumelana nokubhoboza, ukumelana nezinyembezi, nokumelana nomthelela.
Kafushane, izinto zokupakisha zokudla okuqandisiwe zibhekana nezidingo nezinkinga eziningi ezintsha ohlelweni lokufaka isicelo.Ukutadisha nokuxazulula lezi zinkinga kunenzuzo enkulu ekwenzeni ngcono ikhwalithi yokugcinwa nokuthutha kokudla okuqandisiwe.Ngaphezu kwalokho, ukuthuthukisa inqubo yokuhlola ukupakisha kanye nokusungula isistimu yedatha yokuhlola izinto zokupakisha ezihlukahlukene kuzophinde kunikeze isisekelo socwaningo sokukhethwa kwezinto ezizayo nokulawulwa kwekhwalithi.
Uma unayofiqhwafoodpukuvumaizidingo, ungaxhumana nathi.Njenge umenzi wokupakisha oguquguqukayoiminyaka engaphezu kwengu-20, sizokunikeza izixazululo ezifanele zokupakisha ngokuya ngezidingo zomkhiqizo wakho kanye nesabelomali.
Isikhathi sokuthumela: Sep-27-2023
