Iziqinisi ze-PVCyizithasiselo ezisetshenziselwa ukuthuthukisa ukuzinza kokushisa kwe-polyvinyl chloride (PVC) kanye nama-copolymer ayo. Kumapulasitiki e-PVC, uma izinga lokushisa lokucubungula lidlula i-160℃, kuzoqhekeka ukushisa bese kukhiqizwa igesi ye-HCl. Uma kungacindezelwa, lokhu kuqhekeka ukushisa kuzokwanda kakhulu, kuthonye ukuthuthukiswa nokusetshenziswa kwamapulasitiki e-PVC.
Izifundo zithole ukuthi uma amapulasitiki e-PVC equkethe inani elincane likasawoti we-lead, insipho yensimbi, i-phenol, i-aromatic amine, nokunye ukungcola, ukucutshungulwa nokusetshenziswa kwayo ngeke kuthinteke, noma kunjalo, ukubola kwayo kokushisa kungancishiswa ngezinga elithile. Lezi zifundo zikhuthaza ukusungulwa kanye nokuthuthukiswa okuqhubekayo kwama-PVC stabilizers.
Izithambisi ze-PVC ezivamile zifaka phakathi izithambisi ze-organotin, izithambisi ze-metal salt, kanye nezithambisi ze-inorganic salt. Izithambisi ze-Organotin zisetshenziswa kabanzi ekukhiqizweni kwemikhiqizo ye-PVC ngenxa yokucaca kwazo, ukumelana nesimo sezulu okuhle, kanye nokuhambisana kwazo. Izithambisi ze-metal salt zivame ukusebenzisa usawoti we-calcium, i-zinc, noma i-barium, okunganikeza ukuzinza okungcono kokushisa. Izithambisi ze-inorganic salt ezifana ne-tribasic lead sulfate, i-dibasic lead phosphite, njll. zinokuqiniswa kokushisa kwesikhathi eside kanye nokufakwa kahle kukagesi. Lapho ukhetha isithambisi se-PVC esifanele, udinga ukucabangela izimo zokusetshenziswa kwemikhiqizo ye-PVC kanye nezakhiwo zokuqina ezidingekayo. Izithambisi ezahlukene zizothinta ukusebenza kwemikhiqizo ye-PVC ngokomzimba nangokwekhemikhali, ngakho-ke ukwakheka okuqinile nokuhlolwa kuyadingeka ukuqinisekisa ukufaneleka kwezithambisi. Isingeniso esiningiliziwe kanye nokuqhathaniswa kwezithambisi ze-PVC ezahlukahlukene yilezi ezilandelayo:
Isiqinisi se-Organotin:Iziqinisi ze-Organotin ziyiziqinisi ezisebenza kahle kakhulu emikhiqizweni ye-PVC. Ama-compound awo ayimikhiqizo yokusabela kwama-organotin oxides noma ama-organotin chloride anama-acid noma ama-ester afanele.
Izithambisi ze-Organotin zihlukaniswe zibe yizithambisi eziqukethe i-sulfur nezingenaso i-sulfur. Ukuqina kwezithambisi eziqukethe i-sulfur kuyamangalisa, kodwa kunezinkinga ekunambithekeni nasekushintsheni umbala okufana nezinye izithambisi eziqukethe i-sulfur. Izithambisi ze-organotin ezingezona i-sulfur zivame ukusekelwe ku-maleic acid noma i-half maleic acid esters. Ziyathandaiziqinisi ze-methyl tinazisebenzi kahleiziqinisi zokushisangokuqina kokukhanya okungcono.
Iziqinisi ze-Organotin zisetshenziswa kakhulu ekupakisheni ukudla kanye neminye imikhiqizo ye-PVC esobala njengepayipi elibonakalayo.
Iziqinisi Zokuhola:Iziqinisi zomthofu ezijwayelekile zifaka phakathi ama-compounds alandelayo: i-dibasic lead stearate, i-hydrated tribasic lead sulfate, i-dibasic lead phthalate, kanye ne-dibasic lead phosphate.
Njengezinto eziqinisa ukushisa, ama-lead compounds ngeke alimaze izakhiwo zikagesi ezinhle kakhulu, ukumuncwa kwamanzi okuncane, kanye nokumelana nesimo sezulu sangaphandle kwezinto ze-PVC. Kodwa-ke,iziqinisi zomthofubanezinkinga ezifana nalezi:
- Ukuba nobuthi;
- Ukungcola okuphambene, ikakhulukazi ngesulfure;
- Ukukhiqiza i-chloride eholayo, ezokwakha imicu emikhiqizweni eqediwe;
- Isilinganiso esinzima, okuholela esilinganisweni sesisindo/umthamo esingagculisi.
- Iziqinisi zomthofu zivame ukwenza imikhiqizo ye-PVC ingabonakali ngokushesha futhi ishintshe umbala ngokushesha ngemva kokushisa okuqhubekayo.
Naphezu kwalezi zimo ezimbi, iziqinisi zomthofu zisasetshenziswa kabanzi. Ukuze kufakwe ugesi, iziqinisi zomthofu ziyathandwa. Ngenxa yomphumela wazo ojwayelekile, imikhiqizo eminingi ye-PVC eguquguqukayo neqinile iyatholakala njengezingqimba zangaphandle zekhebula, amabhodi aqinile e-PVC angacacile, amapayipi aqinile, izikhumba zokwenziwa, kanye nama-injector.
Izinto zokuqinisa usawoti wensimbi: Iziqinisi zosawoti zensimbi ezixubileziyinhlanganisela yamakhemikhali ahlukahlukene, ngokuvamile aklanywe ngokwezinhlelo zokusebenza ezithile ze-PVC kanye nabasebenzisi. Lolu hlobo lwesiqinisi luguquke kusukela ekufakweni kwe-barium succinate kanye ne-cadmium palm acid kuphela kuya ekuxubeni ngokomzimba kwensipho ye-barium, insipho ye-cadmium, insipho ye-zinc, kanye ne-organic phosphite, nama-antioxidants, izinyibilikisi, izandisi, ama-plasticizer, ama-colorants, ama-UV absorbers, ama-brighteners, ama-viscosity control agents, ama-lubricant, kanye nama-flavour okwenziwa. Ngenxa yalokho, kunezici eziningi ezingathinta umphumela wesiqinisi sokugcina.
Izinto zokuqinisa insimbi, njenge-barium, i-calcium, ne-magnesium azivikeli umbala wokuqala wezinto ze-PVC kodwa zinganikeza ukumelana nokushisa isikhathi eside. Izinto ze-PVC ezizinzile ngale ndlela ziqala ziphuzi/ziwolintshi, bese kancane kancane ziphenduka zibe nsundu, bese ekugcineni zibe mnyama ngemva kokushisa okuqhubekayo.
Iziqinisi ze-Cadmium kanye ne-zinc zaqala ukusetshenziswa ngoba zicacile futhi zingagcina umbala wokuqala wemikhiqizo ye-PVC. Ukuqina kokushisa kwesikhathi eside okunikezwa yiziqinisi ze-cadmium kanye ne-zinc kubi kakhulu kunalokho okunikezwa yiziqinisi ze-barium, ezivame ukuwohloka ngokuzumayo ngokuphelele ngaphandle kophawu oluncane noma olungekho nhlobo.
Ngaphezu kwesilinganiso se-factor yensimbi, umphumela weziqinisi zikasawoti wensimbi uhlobene futhi namakhemikhali azo kasawoti, okuyizinto eziyinhloko ezithinta lezi zakhiwo ezilandelayo: ukuthambisa, ukuhamba, ukucaca, ukushintsha kombala we-pigment, kanye nokuqina kokushisa kwe-PVC. Ngezansi kuneziqinisi eziningana ezivamile zensimbi ezixubile: i-2-ethylcaproate, i-phenolate, i-benzoate, kanye ne-stearate.
Iziqinisi zikasawoti wensimbi zisetshenziswa kabanzi emikhiqizweni ethambile ye-PVC kanye nemikhiqizo ethambile ye-PVC esobala njengokupakishwa kokudla, izinto ezisetshenziswayo zezokwelapha, kanye nokupakishwa kwemithi.
Isikhathi sokuthunyelwe: Okthoba-11-2023