Ucwaningo Lweminyaka Engu-40 Ngama-Silicone Sealants: Ukuqhathaniswa Nokunye Ukwakhiwa Kwekhemikhali

Njengoba izinhlelo zokucwenga zezakhiwo zikhula ziba yinkimbinkimbi futhi ziba yinkimbinkimbi, futhi njengoba izidingo zokuqina nokusimama zilokhu zanda, impilo yesevisi yezinto zokwakha isibucayi kakhulu kunangaphambili.

Ama-sealant abalulekile-ekusebenzeni kwesikhathi eside kanye nokumelana nesimo sezulu sezindonga zamakhethini kanye nezinhlelo zokucwebezelisa. Ukukhethwa kwesitywini esifanelekile kunganquma ukuthi isakhiwo sijabulela amashumi eminyaka{2}okusebenza ngokulungiswa okuphansi noma sibhekane nokulungiswa okubizayo kanye nokuwohloka kwesistimu.

Eqinisweni, sekuyisikhathi eside kuqashelwa ukuthi "impahla yokuvala ngokuvamile iyingxenye ebaluleke kakhulu yokuhlanganiswa okuhlanganyelwe okuthonya ukuqina"-iphuzu eliqokonyiswe kunguqulo yango-1966 Yamazinga Onga Isikhathi (Umfanekiso 1).2

Kodwa yikuphi ukwakheka kwamakhemikhali okungamelana nokuhlolwa kwesikhathi?

Leli phepha lethula imiphumela yolunye lwezifundo ezinde kakhulu-eziqhutshwe ngama-glazing sealants{1}}iminyaka engama-40-ehlola isimo sezulu sangaphandle seminyaka engu-40{3} esiqhathanisa ama-silicone{5}ama-sealant asekelwe nalawo enziwe nge-polyurethane kanye ne-acrylic chemistries. Kwenziwe Esikhungweni Sokuhlola Isimo Sezulu Se-Atlas e-Florida, lolu cwaningo lwangempela-lomhlaba lunikeza isiqondiso esibalulekile kubaklami bezakhiwo, izicacisi zezinto ezibonakalayo, onjiniyela bezimvilophu zokwakha, nosonkontileka abahlose ukwenza ukukhetha kwezinto ezinolwazi olunomthelela kuzo zonke izici zemvilophu yokwakha.

Ucwaningo lugxile ekusebenzeni kokwakheka kwe-silicone, ikakhulukazi izinhlobo ze-acetoxy ne-alkoxy, ngokuhlola izici ezibalulekile ezifana namandla okunamathela, amandla ahlangene, ukuguquguquka, ukuqina, ukuqina, ukuqina, isimo esingaphezulu,-nokuqina kwesikhathi eside uma kuvezwe ukushisa okukhulu, imisebe ye-ultraviolet (UV), kanye nomswakama ophezulu. Iphinde inikeze idatha yokuqhathanisa ukusekela izinqumo zokucaciswa.

Ukubaluleka-Kwedatha Ende Yokusebenza Kwesikhathi

Izakhiwo zesimanje ziklanyelwe ukuhlala amashumi amaningi eminyaka, kanti ezinye ngisho namakhulu eminyaka. Ngalesi sizathu, kubalulekile ukuthi izinto zokusebenza zamanje zibe nedatha-yesikhathi eside yokusebenza ngaphansi{2}}kwezimo zomhlaba zangempela. Nakuba ukuhlolwa kokuguga okusheshisiwe kunikeza ulwazi oluwusizo, ngeke kuthathe indawo yemininingwane etholwe{4}}ekuhlolweni kokuchayeka ngaphandle kwesikhathi eside.

Ukuze kubhekwane nalesi sidingo, i-GE Silicones (manje eyaziwa ngokuthi yi-Momentive Performance Materials) yaqala olunye lwezifundo ze-sealant ze-sealant ezifisa kakhulu emhlabeni ngo-1983. Lolu cwaningo lwaluhilela ukusebenzisa amakhemistri ahlukahlukene ukuze ahlole amaphaneli nokuwachaya esimweni sezulu esishisayo saseFlorida isikhathi eside.

I-9-hectare (22-acre) I-Atlas Weathering Test Site-indawo yokuqala yokuhlola egunyazwe uMkhandlu Wokulinganisa Uphahla Olupholile-inikeze indawo ekahle yocwaningo. Isimo sezulu saseFlorida, esibonakala ngomswakama ophezulu, imisebe ye-UV enamandla, neziphepho ezivame kakhulu zasezindaweni ezishisayo, siphakathi kwezindawo zemvelo ezidinga kakhulu ukuhlola ukuqina kwezinsimbi ezicwebezelayo.

Okutholakele Okubalulekile: Isifinyezo

Ngemva kweminyaka engu-40 yokuchayeka ngaphandle, imiphumela yayicacile: ama-silicone sealants ahlala edlula i-polyurethane nama-acrylic sealant ngokuhlala isikhathi eside, ukululama okunwebekayo, nobuqotho bendawo, okufakazela{1}}amakhono azo okusebenza kwesikhathi eside. Nakuba ucwaningo lugxile ikakhulukazi kuma-sealants, lezi zakhiwo ezifanayo zamakhemikhali zisetshenziswa kakhulu odongeni lwamakhethini kanye nezicelo zokucwenga.