Ukubumba ngomjovo kungenye yezinqubo zokukhiqiza eziguquguqukayo nezisebenza kahle kakhuluImikhiqizo ye-PVC (polyvinyl chloride), okuvumela ukukhiqizwa kwezimo eziyinkimbinkimbi ngokunemba okuqhubekayo—kusukela ezingxenyeni zezimoto kanye nezindawo zokuvala zikagesi kuya kumadivayisi ezokwelapha kanye nezimpahla zasekhaya. Noma kunjalo, isakhiwo sama-molecule se-PVC esingokwemvelo siletha inselele eyingqayizivele ngesikhathi sokucubungula: asizinzile ngokwemvelo uma sivezwa emazingeni okushisa aphezulu (ngokuvamile angu-160–220°C) kanye namandla okusika atholakala ekubunjweni komjovo. Ngaphandle kokuzinza okufanele, i-PVC izobola, okuholela ekushintsheni kombala (ukuphuzi noma ukuba nsundu), ukwehla kwezakhiwo zemishini, ngisho nokukhishwa kwemikhiqizo eyingozi. Yilapho iziqinisi ze-PVC zingena khona njengamaqhawe angakadunyiswa, hhayi nje kuphela ekuvimbeleni ukubola kodwa futhi nokwenza ngcono ukusebenza kokucubungula nokuqinisekisa ukuthi umkhiqizo wokugcina uhlangabezana nezindinganiso zekhwalithi. Kule bhulogi, sizongena endimeni ebalulekile yeziqinisi ze-PVC ekubunjweni komjovo, sihlole izinhlobo ezivame kakhulu, futhi sihlole ukuthi zithonya kanjani imingcele ebalulekile yokucubungula kanye nokusebenza komkhiqizo wokugcina.
Ukuze uqonde ukuthi kungani iziqinisi zingaxoxiswana ngokubumba umjovo we-PVC, kubalulekile kuqala ukuqonda imbangela yokungazinzi kwe-PVC. I-PVC iyi-polymer ye-vinyl eyakhiwe yi-polymerization yama-monomers e-vinyl chloride, futhi uchungechunge lwayo lwama-molecule luqukethe izibopho ze-chlorine-carbon ezibuthakathaka. Uma zishiswa emazingeni okushisa adingekayo ekubumbeni umjovo, lezi zibopho ziyaqhekeka, ziqale ukusabela kochungechunge lokuwohloka. Le nqubo, eyaziwa ngokuthi i-dehydrochlorination, ikhipha igesi ye-hydrogen chloride (HCl)—into egqwalisayo esheshisa kakhulu ukuwohloka futhi yonakalise imishini yokubumba. Ngaphezu kwalokho, i-dehydrochlorination iholela ekwakhekeni kwezibopho ezimbili ezihlanganisiwe kuchungechunge lwe-PVC, ezibangela ukuthi izinto ziphenduke ziphuzi, bese ziba nsundu, futhi ekugcineni zibe buthakathaka. Kwababumba umjovo, lokhu kuhunyushwa ezingxenyeni ezilahliwe, izindleko zokulungisa ezengeziwe, kanye nokungalandeli imithetho yokuphepha nekhwalithi. Ababambi umjovo baphazamisa lo mjikelezo wokuwohloka ngokumunca i-HCl, ukunciphisa imikhiqizo ye-acidic, noma ukususa ama-free radicals aqhuba ukusabela kochungechunge—ukuvikela ngempumelelo i-PVC ngesikhathi sokucubungula nokwandisa impilo yenkonzo yezinto.
Akuzona zonkeIziqinisi ze-PVCKudalwa ngokulinganayo, futhi ukukhetha uhlobo olufanele lokubumba ngomjovo kuncike ezintweni eziningi ezahlukene: izinga lokushisa lokucubungula, isikhathi somjikelezo, ubunzima besikhunta, izidingo zomkhiqizo wokugcina (isb., ukuthintana kokudla, ukumelana ne-UV), kanye nemithethonqubo yezemvelo. Ngezansi umbono oqhathaniswayo wezinhlobo ze-stabilizer ezisetshenziswa kakhulu ekubumbeni ngomjovo, izindlela zazo zokusebenza, kanye nezinzuzo nezimbi ezibalulekile zokucubungula izinhlelo zokusebenza:
| Uhlobo Lokuzinzisa | Indlela Yokusebenza | Izinzuzo Zokubumba Umjovo | Ukulinganiselwa | Izicelo Ezijwayelekile |
| Susa i-HCl bese wakha izibopho eziqinile ngamaketanga e-PVC; vimbela ukuqhekeka kweketanga nokuxhumanisa | Ukuqina kokushisa okuhle kakhulu emazingeni okushisa aphezulu okujova; isidingo esincane somthamo; umthelela omncane ekugelezeni kokuncibilika; kukhiqiza izingxenye ezicacile, eziqinile ngombala | Izindleko eziphakeme; ezinye izinhlobo zikhawulelwe ekusetshenzisweni kokudla noma kwezokwelapha; izinkinga ezingaba khona zemvelo | Imikhiqizo ye-PVC ecacile (isb., amapayipi ezokwelapha, izitsha zokudla); izingxenye zezimoto ezinembe kakhulu | |
| Isenzo esiphindwe kabili: Usawoti we-Ca umunca i-HCl; Usawoti we-Zn ususa ama-free radicals; uvame ukuhlanganiswa nama-co-stabilizers (isb., uwoyela ofakwe i-epoxidized) | Inobungani nemvelo (ayinansimbi enamandla); ihambisana nemithetho yokudla kanye neyokwelashwa; iyakwazi ukucutshungulwa kahle ngezikhathi zomjikelezo omude | Ukuqina kokushisa okuphansi kune-organotins (kungcono kakhulu ku-160–190°C); kungabangela ukushintsha kombala okuncane emazingeni okushisa aphezulu; kudingeka umthamo ophezulu | Ukupakishwa kokudla, amathoyizi, amadivayisi ezokwelapha, izimpahla zasekhaya | |
| Munca i-HCl bese wakha i-lead chloride enganyibiliki; hlinzeka ngokuqina kokushisa kwesikhathi eside | Ukuqina kokushisa okumangalisayo; izindleko eziphansi; ukuhambisana kahle ne-PVC; kufanelekile ekucutshungulweni kwezinga lokushisa eliphezulu | Ubuthi (insimbi esindayo); kuvinjelwe ezindaweni eziningi ngemikhiqizo yabathengi neyezokwelapha; izingozi zemvelo | Amapayipi ezimboni (ezindaweni ezingalawulwa); izingxenye ezisindayo ezingadingi umthengi | |
| Iziqinisi zeBarium-Cadmium | Usawoti we-Ba umunca i-HCl; usawoti we-Cd ususa ama-free radicals; umphumela wokubambisana uma uhlanganisiwe | Ukuqina okuhle kokushisa; ukugcinwa kombala okuhle kakhulu; kufanelekile ekubunjweni kwe-PVC okuguquguqukayo nokuqinile | I-Cadmium inobuthi; inqunyelwe ezimakethe eziningi zomhlaba; izingozi zemvelo nezempilo | Izicelo ezindala (eziqediwe ezindaweni eziningi); eminye imikhiqizo yezimboni engeyona eyabathengi |
Esimweni samanje sokulawula, ukuhola kanyeIziqinisi ze-Ba-Cdziye zasuswa kakhulu ngenxa yezindlela ze-organotin kanye ne-Ca-Zn, ikakhulukazi emikhiqizweni ebhekene nabathengi kanye neyokwelapha. Kwababumbi bomjovo, lolu shintsho luye lwasho ukuzivumelanisa nezici zokucubungula ezihlukile zalezi ziqinisi eziphephile—isibonelo, ukulungisa amazinga okushisa noma izikhathi zomjikelezo ukuze kuhlangatshezwane nokuqina kokushisa okuphansi kwe-Ca-Zn, noma ukulinganisa izindleko nokusebenza lapho usebenzisa ama-organotins.
Umthelela weziqinisi ekusebenzeni kokucubungula i-PVC ekubunjweni komjovo udlulela ngale nje kokuvimbela ukuwohloka. Uthonya ngqo amapharamitha okucubungula abalulekile njengenkomba yokugeleza kokuncibilika, isikhathi somjikelezo, ukugcwaliswa kwesikhunta, kanye nokusetshenziswa kwamandla—konke okuthinta ukusebenza kahle kokukhiqiza kanye nekhwalithi yengxenye. Ake sihlukanise le miphumela ngomongo wezwe langempela: ukugeleza kokuncibilika, isibonelo, kubalulekile ekuqinisekiseni ukuthi inhlanganisela ye-PVC igcwalisa izikhala zesikhunta eziyinkimbinkimbi ngokulinganayo futhi ngaphandle kwamaphutha njengezithombe ezimfushane noma imigqa yokushisela. Iziqinisi ze-Organotin, ngenxa yomthamo wazo ophansi kanye nokuhambisana okuhle kakhulu ne-PVC, zinomthelela omncane ku-MFI, okuvumela ukuncibilika ukuthi kugeleze kahle ngisho nasezigabeni ezinezindonga ezincane noma amajiyometri ayinkimbinkimbi.Iziqinisi ze-Ca-ZnNgakolunye uhlangothi, kungakhuphula kancane i-melt viscosity (ikakhulukazi ngemithamo ephezulu), kudinge ababumbi ukuthi balungise ingcindezi yomjovo noma izinga lokushisa ukuze balondoloze ukugeleza okuhle. Lokhu kuyinto ebalulekile okufanele icatshangelwe lapho ushintsha kusuka kuma-organotins kuya ku-Ca-Zn ukuze kulandelwe imithetho—ukulungiswa okuncane kuya kumapharamitha okucubungula kungenza umehluko omkhulu kwikhwalithi eyingxenye.
Isikhathi sokujikeleza singenye into ebalulekile kuma-injection molders, njengoba sithinta ngqo umkhiqizo. Ama-stabilizer anokuqina kokushisa okuqinile, njenge-organotins noma i-lead (nakuba manje ivinjelwe), avumela izikhathi zomjikelezo ezimfushane ngokunika amandla amazinga okushisa aphezulu okucubungula ngaphandle kokuwohloka. Amazinga okushisa aphezulu anciphisa i-melt viscosity, asheshise ukugcwaliswa kwesikhunta, futhi afinyeze izikhathi zokupholisa—konke okukhulisa umkhiqizo. Ngokuphambene nalokho, ama-stabilizer anokuqina kokushisa okuphansi, njenge-Ca-Zn, angadinga izikhathi zomjikelezo ezinde ukuze agweme ukushisa ngokweqile, kodwa lokhu kushintshana kuvame ukufaneleka ngezinzuzo zawo zemvelo kanye nokuhambisana nomthetho. Ama-molders anganciphisa lokhu ngokwenza ngcono ezinye izilinganiso, njengokusebenzisa izilawuli zokushisa kwesikhunta noma ukulungisa isivinini sesikulufo ukuze kuncishiswe ukushisa okubangelwa ukucheba.
Ukuzinza kokusika nakho kuyinto ebalulekile okufanele icatshangelwe, ikakhulukazi ngezinqubo zokubumba umjovo ezibandakanya isivinini esikhulu sezikulufo. Amandla okusika akhiqiza ukushisa okwengeziwe ekuncibilikeni kwe-PVC, okwandisa ingozi yokuwohloka. Izithambisi ezingamelana nokusika okuphezulu—njenge-organotins kanye ne-Ca-Zn blends esebenza kahle—zisiza ukugcina ubuqotho bokuncibilika ngaphansi kwalezi zimo, zivimbele ukushintsha kombala futhi ziqinisekise izakhiwo zezingxenye ezihambisanayo. Ngokuphambene nalokho, izithambisi zekhwalithi ephansi zingase ziwohloke ngaphansi kokusika okuphezulu, okuholela ekugelezeni kokuncibilika okungalingani kanye namaphutha afana namabala angaphezulu noma ukucindezeleka kwangaphakathi.
Ukusebenza komkhiqizo wokugcina kuncike ngokulinganayo ekukhetheni isiqinisi. Isibonelo, imikhiqizo ye-PVC yangaphandle (isb. ifenisha yengadi, ukumbozwa kwangaphandle) idinga iziqinisi ezinokumelana ne-UV ukuvimbela ukuwohloka elangeni. Iziqinisi eziningi ze-Ca-Zn kanye ne-organotin zingakhiwa ngeziqinisi ze-UV noma iziqinisi ze-amine ezivinjiwe (HALS) ukuze kuthuthukiswe ukuqina kwesimo sezulu. Emikhiqizweni ye-PVC eqinile njengezinto zokufaka amapayipi noma izivalo zikagesi, iziqinisi ezithuthukisa amandla omthelela kanye nokuqina kobukhulu zibalulekile. I-Organotins, ikakhulukazi, yaziwa ngokulondoloza izakhiwo zemishini ze-PVC eqinile ngesikhathi sokucubungula, ukuqinisekisa ukuthi izingxenye zingamelana nokucindezeleka futhi zigcine isimo sazo ngokuhamba kwesikhathi.
Izicelo zokuxhumana nokudla kanye nezokwelapha zidinga iziqinisi ezingenabo ubuthi futhi ezihambisana nezindinganiso zomhlaba wonke. Iziqinisi ze-Ca-Zn ziyindinganiso yegolide lapha, njengoba zingenazo izinsimbi ezisindayo futhi zihlangabezana nezidingo zokuphepha eziqinile. Ama-Organotins nawo asetshenziswa kwezinye izinhlelo zokuxhumana nokudla, kodwa kuphela izinhlobo ezithile (isb., i-methyltin, i-butyltin) ezivunyelwe ukusetshenziswa okunjalo. Abakhi bezinto zobumba abasebenza kule mikhakha kumele baqinisekise ngokucophelela ukuthi ziyahambisana yini nezindlela zabo zokuvumelanisa ukuze bagweme izinkinga zomthetho futhi baqinisekise ukuphepha kwabathengi.
Uma ukhethaIsiqinisi se-PVC sokubumba umjovo, kunezindlela eziningana ezisebenzayo okufanele uzicabangele ngale kohlobo nokusebenza nje kuphela. Ukuhambisana nezinye izithako kubalulekile—ama-PVC compounds avame ukuqukatha ama-plasticizer, ama-lubricant, ama-filler, kanye nama-pigment, futhi i-stabilizer kumele isebenze ngokubambisana nalezi zingxenye. Isibonelo, amanye ama-lubricant anganciphisa ukusebenza kwama-stabilizer ngokwenza isithiyo phakathi kwe-stabilizer kanye ne-PVC matrix, ngakho-ke ama-molders angadinga ukulungisa amazinga okugcoba noma akhethe i-stabilizer ehambisana kangcono. Isilinganiso esinye isici esibalulekile: ukusebenzisa i-stabilizer encane kakhulu kuzoholela ekuvikelekeni okwanele kanye nokuwohloka, kuyilapho ukusebenzisa okuningi kakhulu kungaholela ekuqhakazeni (lapho i-stabilizer ithuthela khona ebusweni bengxenye) noma ukwehla kwezakhiwo zemishini. Abakhiqizi abaningi be-stabilizer banikeza ububanzi bemithamo enconywayo ngokusekelwe ohlotsheni lwe-PVC (eqinile vs. eguquguqukayo) kanye nezimo zokucubungula, futhi kubalulekile ukulandela lezi ziqondiso ngenkathi kwenziwa ukuhlolwa ukuze kuthuthukiswe ukusebenza.
Imikhuba yezemvelo kanye neyokulawula nayo ibumba ikusasa lama-PVC stabilizers okufakelwa umjovo. Ukucindezela komhlaba wonke kokusimama kuholele ekwandeni kwesidingo sama-bio-based noma abolakala kalula, yize lokhu kusesezigabeni zokuqala zokuthuthukiswa. Ngaphezu kwalokho, imithetho evimbela ukusetshenziswa kwamakhemikhali athile (isb., i-REACH e-EU) iqhuba ukusungula izinto ezintsha ekwakhiweni okuphephile, okunobungani nemvelo. Ama-molders kufanele ahlale enolwazi ngalezi zindlela ukuqinisekisa ukuthi izinqubo zawo zihlala zihambisana futhi zincintisana. Isibonelo, ukushintshela kuma-Ca-Zn stabilizers manje kungasiza ekugwemeni ukuphazamiseka uma imithetho eqinile kuma-organotins isetshenziswa esikhathini esizayo.
Ukuze sibonise umthelela wangempela wokukhetha i-stabilizer, ake sicabangele isifundo secala: umshini wokwakha okhiqiza izimbobo zikagesi ze-PVC eziqinile ngokufaka i-injection molding wawubhekene nokuphuzi njalo kwezingxenye kanye namazinga aphezulu e-scrap. Uphenyo lokuqala lwembule ukuthi umshini wokwakha wawusebenzisa i-Ba-Cd stabilizer eshibhile, eyayingagcini nje ngokungalandeli imithetho ye-EU kodwa futhi yayivikela ngokwanele i-PVC ekushiseni okuphezulu kokucubungula (200°C) okudingekayo ekwakhiweni kwe-mold okuyinkimbinkimbi. Ngemva kokushintshela ku-organotin stabilizer esebenza kahle, inkinga yokuphuzi yaqedwa, amazinga e-scrap ehla ngo-35%, futhi izingxenye zahlangabezana nezindinganiso zokuphepha ze-EU. Umshini wokwakha uphinde wabona ukugeleza kokuncibilika okuthuthukisiwe, okunciphisa ingcindezi yomjovo futhi kwanciphisa izikhathi zomjikelezo ngo-10%, okwandisa umkhiqizo jikelele. Kwesinye isibonelo, umenzi wezitsha ze-PVC zezinga lokudla washintsha kusuka kuma-organotins waya ku-Ca-Zn stabilizer ukuze ahlangabezane nezidingo ze-FDA. Nakuba kwadingeka balungise izinga lokushisa lokucubungula kancane (belihlise kusukela ku-195°C liye ku-185°C) ukuze balondoloze ukuzinza, iswishi yayingenamthungo futhi inomthelela omncane esikhathini sokujikeleza, futhi izingxenye zagcina ukucaca kwazo kanye nezakhiwo zazo zemishini.
Iziqinisi ze-PVC zibalulekile ekubunjweni komjovo okuphumelelayo, zisebenza njengabavikeli ekuwohlokeni nasekusebenzeni kahle kokucubungula. Ukukhetha isiqinisi—kungaba yi-organotin, i-Ca-Zn, noma olunye uhlobo—kumele kuhambisane nezimo ezithile zokucubungula, izidingo zomkhiqizo wokugcina, kanye nemikhawulo yokulawula. Abakhi bezinto zokuhlobisa abachitha isikhathi ekukhetheni isiqinisi esifanele kanye nokwenza ngcono amapharamitha okucubungula ngokusekelwe kulolo khetho bazozuza emazingeni aphansi okulahlwa, umkhiqizo ophezulu, kanye nezingxenye ezisezingeni eliphezulu ezihlangabezana nezindinganiso zokuphepha nokusebenza. Njengoba imboni iqhubeka nokuguqukela ekuzinzeni kanye nemithetho eqinile, ukuhlala unolwazi ngobuchwepheshe bamuva bokuzinzisa kanye nezitayela kuzoba yisihluthulelo sokugcina umkhawulo wokuncintisana. Kungakhathaliseki ukuthi ukhiqiza izingxenye ze-PVC eziqinile noma eziguquguqukayo, zokusetshenziswa ngabathengi noma ezimbonini, isiqinisi esifanele siyisisekelo senqubo yokubumba yomjovo ephumelelayo.
Isikhathi sokuthunyelwe: Jan-29-2026