Isikhumba sokwenziwa esisekelwe ku-PVC (i-PVC-AL) sisalokhu siyinto evelele ezindlini zezimoto, ezindlini zokuhlobisa, nasezindwangu zezimboni ngenxa yokulinganisela kwezindleko, ukucutshungulwa, kanye nokuguquguquka kobuhle. Kodwa-ke, inqubo yaso yokukhiqiza ihlushwa yizinselele zobuchwepheshe ezigxile ezicini zamakhemikhali ze-polymer—izinselele ezithinta ngqo ukusebenza komkhiqizo, ukuhambisana nemithetho, kanye nokusebenza kahle kokukhiqiza.
Ukuwohloka Kokushisa: Isithiyo Esiyisisekelo Sokucubungula
Ukungazinzi okungokwemvelo kwe-PVC emazingeni okushisa ajwayelekile okucubungula (160–200°C) kuyimbangela eyinhloko. I-polymer idlula ekususeni i-hydrochlorination (ukususwa kwe-HCl) nge-self-catalyzed chain reaction, okuholela ezinkingeni ezintathu zokuqhekeka:
• Ukuphazamiseka kwenqubo:I-HCl ekhishwe idla imishini yensimbi (ama-calendars, ama-coating dies) futhi ibangele i-gelation ye-matrix ye-PVC, okuholela ezifweni ze-batch ezifana nama-blister ebusweni noma ukujiya okungalingani.
• Ukushintsha kombala komkhiqizo:Uchungechunge lwe-polyene oluhlanganisiwe olwakhiwe ngesikhathi sokuwohloka lunikeza umbala ophuzi noma onsundu, okwehluleka ukuhlangabezana nezindinganiso eziqinile zokuvumelana kombala zezicelo eziphezulu.
• Ukulahlekelwa yimpahla yemishini:Ukusikwa kweketanga kwenza buthaka inethiwekhi ye-polymer, kunciphisa amandla okuthamba kwesikhumba esiqediwe kanye nokumelana nokudabuka kufikela ku-30% ezimweni ezimbi kakhulu.
Izingcindezi Zokuthobela Imithetho Yezemvelo Nemithetho
Ukukhiqizwa kwe-PVC-AL kwendabuko kubhekene nokuhlolwa okwandayo ngaphansi kwemithetho yomhlaba wonke (isb., amazinga e-EU REACH, i-US EPA VOC):
• Ukukhishwa kwe-Volatile organic compound (VOC):Ukuwohloka kokushisa kanye nokufakwa kwe-plasticizer okusekelwe ku-solvent kukhipha ama-VOC (isb., ama-phthalate derivatives) adlula imingcele yokukhishwa.
• Izinsalela zensimbi esindayo:Izinhlelo zokuzinzisa ezidala (isb., umthofu, okusekelwe ku-cadmium) zishiya ukungcola okuncane, okwenza imikhiqizo ingafaneleki ekuqinisekisweni kwelebula le-eco (isb., i-OEKO-TEX® 100).
• Ukuphinda kusetshenziswe ekupheleni kokuphila:I-PVC engazinzile iyonakala kakhulu ngesikhathi sokuvuselela kabusha ngomshini, ikhiqize i-leachate enobuthi futhi yehlise ikhwalithi yokudla okusetshenzisiwe.
Ukuqina Okubi Ngaphansi Kwezimo Zesevisi
Ngisho ne-PVC-AL engazinzile, ekhiqizwa ngemuva kokukhiqizwa ikhula ngokushesha:
• Ukuwohloka okubangelwa yi-UV:Ukukhanya kwelanga kubangela ukushiswa kwe-photo, kuphule amaketanga e-polymer futhi kubangele ukuphuka—okubaluleke kakhulu ezindlini zokugqoka zezimoto noma zangaphandle.
• Ukufuduka kwe-plasticizer:Ngaphandle kokuqinisa i-matrix okusekelwe ekuzinziseni, ama-plasticizer ahamba ngokuhamba kwesikhathi, okuholela ekuqineni nasekuqhekekeni.
Indima Yokunciphisa Izinzisi ze-PVC: Izindlela kanye Nenani
Iziqinisi ze-PVC zibhekana nalezi zindawo zobuhlungu ngokubhekisa ezindleleni zokuwohloka ezingeni lama-molecule, ngezinhlobo zesimanje ezihlukaniswe ngezigaba ezisebenzayo:
▼ Iziqinisi Zokushisa
Lezi zisebenza njengezihlanzi ze-HCl kanye neziqedi zochungechunge:
• Ziqeda i-HCl ekhishwe (ngokusabela ngensipho yensimbi noma ama-ligand e-organic) ukuze zimise ukuhlaziywa kwe-autocatalysis, zandise ukuqina kwefasitela ngemizuzu engama-20-40.
• Ama-co-stabilizer e-organic (isb., ama-phenol avinjiwe) abamba ama-free radical akhiqizwa ngesikhathi sokuwohloka, alondoloze ubuqotho be-molecule chain futhi avimbele ukushintsha kombala.
▼ Iziqinisi Zokukhanya
Zihlanganiswe nezinhlelo zokushisa, zimunca noma zichithe amandla e-UV:
• Izifutho ze-UV (isib. ama-benzophenones) ziguqula imisebe ye-UV ibe ukushisa okungenangozi, kuyilapho iziqinisi zokukhanya kwe-amine ezivinjiwe (HALS) ziphinda zivuselele izingxenye ze-polymer ezonakele, ziphinde kabili impilo yenkonzo yangaphandle yento.
▼ Amafomula Anobungani Nemvelo
Iziqinisi ezihlanganisiwe ze-Calcium-zinc (Ca-Zn)zithathe indawo yezinhlobo zensimbi esindayo, zihlangabezana nezidingo zomthetho ngenkathi zigcina ukusebenza kahle. Ziphinde zinciphise ukukhishwa kwe-VOC ngo-15-25% ngokunciphisa ukuwohloka kokushisa ngesikhathi sokucubungula.
Izinzisi njengesixazululo esiyisisekelo
Izithasiselo ze-PVC azizona nje izithasiselo—ziyizinto ezisiza ekukhiqizweni kwe-PVC-AL okusebenzayo. Ngokunciphisa ukuwohloka kokushisa, ukuqinisekisa ukuthobela imithetho, nokuthuthukisa ukuqina, zixazulula amaphutha angaphakathi e-polymer. Lokho kusho ukuthi, azikwazi ukubhekana nazo zonke izinselele zemboni: intuthuko kuma-plasticizer asekelwe ku-bio kanye nokuvuselelwa kwamakhemikhali kusadingeka ukuze kuhambisane ngokugcwele nemigomo yomnotho oyindilinga. Kodwa-ke, okwamanje, izinhlelo zokuzinzisa ezilungiselelwe kahle ziyindlela evuthiwe kakhulu kwezobuchwepheshe futhi engabizi kakhulu yesikhumba sokwenziwa se-PVC esisezingeni eliphezulu, esihambisanayo.
Isikhathi sokuthunyelwe: Novemba-12-2025