UDkt BP van der Wal, Merit Medical Coatings kanye noCharles Fields, Whitford Corporation, baxoxa ngokusetshenziswa kwezingubo ze-PTFE emishinini yezokwelapha ye-intravascular.
Kube nezingxoxo eziningi mayelana nezingubo ze-PTFE emakethe yemishini yezokwelapha esebenza ngemithambo.NgoNovemba, 2015 i-FDA yakhipha ukuxhumana kokuphepha okubhekisela emiphumeleni yokwehliswa kwe-coating kumadivayisi we-intravascular ezithendeni zezigameko ezimbalwa ezibikiwe.Iminyaka eminingi, i-PTFE coatings ibinguzakwethu othulile, enciphisa ukungqubuzana nsuku zonke ezinqubweni ze-catheterization.Seziphenduke indawo yonke, isiphetho sempahla ezingxenyeni ezijwayelekile ze-catheter.
Ingcindezi yokulawula eqhubekayo embonini yamakhemikhali ihlale iphoqa ushintsho.Abafundi bangase bakhumbule ukuthi i-PFOA (Perfluorooctanic acid) yayilawulwa ngaphandle kokukhiqizwa kwe-fluoropolymer.Lolu shintsho lube nomthelela kukho kokubili ukusebenza kokumboza kanye nezidingo zohlelo lokusebenza.Lokhu akusona isenzakalo esisha.Abakhiqizi bezingubo zokumboza bahlale bephoqeleka ukuthi babhekane nezinguquko ezisebenzayo zezinto ezingavuthiwe ezihlanganisa izincibilikisi, ama-pigments, nama-resin.Lokhu akuhambisani kahle nemakethe yemishini yezokwelapha.Nakuba imboni yemishini yezokwelapha inezinqubo ezikhona zokubhekana nokushintsha kwezinto, kuvame ukuthatha isikhathi futhi okuvame ukubiza ukwenza umsebenzi.Lezi zinguquko zibonakala zikhula njengoba izidingo zomhlaba jikelele zemikhiqizo eluhlaza nephephile ziba umshayeli onzima kakhulu.Izinto zamanje zokusetshenziswa ezihlolwayo zifaka i-Chrome 6 (i-hexavalent chromium) ne-NMP (N-methyl-2-pyrrolidone).Lezi izinto ezibalulekile ekwakhiweni kwezindwangu eziningi ze-fluoropolymer (PTFE) ezisetshenziswa ezingxenyeni ze-catheter.Abakhiqizi bemishini yezokwelapha emithanjeni kuzodingeka balungiselele ukubhekana nalezi zinguquko zokumboza ukuze baqinisekise ukuthi izinqubo zokumboza ziyahlangabezana nezidingo zabo zokusetshenziswa kokugcina.
I-Merit Medical Coatings, indawo yayo yokuhlanganisa izintambo etholakala e-Venlo, e-Netherlands, ibithatha indlela yokubhekana nezingcindezi ezingokomthetho ezibekwa embonini ye-fluoropolymer.UDkt BP van der Wal, unjiniyela omkhulu uthe: “Ukusetshenziswa kwe-(PTFE) okokunamathela ezintanjeni zezokwelapha kudinga ubuchwepheshe obukhulu.Ubukhulu obuncane kanye nokuguquguquka kwemishini eminingi yezokwelapha kwenza inqubo yokumboza ibe inselele futhi ihluke ngokuphelele enqubweni yokumboza yama-substrates ayisicaba futhi aqinile njengezinto zokupheka.Umthamo wokushisa ophansi kakhulu wama-substrates afana nezintambo udinga izikhathi zokucubungula ezihluke ngokuphelele nezinga lokushisa.”
Kunezindlela ezimbili ezihlukene zokufaka isicelo: I-pre-coating kanye ne-post-coating.Enkambweni yangaphambi kokugqoka, ukugqoka kusetshenziselwa i-substrate ngaphambi komhlangano.Ngokuvamile, inqubo yokumboza ngaphambili isetshenziselwa ukucutshungulwa kwevolumu ephezulu lapho i-substrate ivumela ukucutshungulwa kwe-reel-to-reel.I-pre-coating iyinqubo eqhubekayo evumela isivinini sokumboza esiphezulu kanye nomphumela wokuhlanganisa ohambisana kakhulu we-reel egcwele yezinto.Okwezintambo zokuqondisa, lokhu kusho ukuthi i-coating isetshenziswa entanjeni ngenqubo ye-reel-to-reel ngaphambi kokubhinca.Ngakho-ke ukumboza kufanele kumelane nawo wonke amandla asetshenziswa enqubweni yokuhlanganisa.Isibonelo, ukumboza akufanele kuncibilike ocingweni ngesikhathi sekhoyili.Lokhu kudinga kakhulu enamathela ngenxa yamandla aphezulu asetshenziswa ucingo kanye deformation umphumela.Amapharamitha afana nokujiya kokumboza abalulekile ukwenza ukunamathela kuguquguquke futhi kuqine ngokwanele.
Ekuhlanganisweni kwe-post-coating, izinqubo zokuhlanganisa ucingo lwe-catheter seziqediwe kakade.I-post-coating iyinqubo yenqwaba futhi ikhethwa uma i-substrate ingakuvumeli ukucutshungulwa kwe-reel-to-reel, njengocingo olunethiphu eliphansi.I-post-coating iphinde inikeze ukuguquguquka okwengeziwe ukugqoka ingxenye ye-substrate kuphela.Ngokuvala ingxenye ye-substrate, amabhande omaka angashiywa phezulu.Ifilimu eyomile elandelayo ayidingeki ukuthi imelane namandla amakhulu emishini yokugoqa nezinye izinqubo zokukhiqiza izintambo.Lokhu akwenzi uhlelo lokusebenza lokumboza lungabi nesidingo esincane.With the pre-enamathela inqubo enamathela ukwehluleka ukunamathela kwakuyobonakala ngesikhathi inqubo umhlangano.Ngenqubo ye-post-coating yokunamathela ukwehluleka ukunamathela kungenzeka ngesikhathi sokuxhumana nesiguli uma kungabanjwa ngesikhathi sokuhlolwa kwe-QA.Lesi kungaba isimo esiyingozi esibeka izidingo ezibucayi kakhulu ezinqubweni zokufaka isicelo sokumboza.
Ngezembatho ze-fluoropolymer, impahla enganamathele kanye nokunamathela okuhle ku-substrate kuyaphikisana.Ukwengeza, izintambo zokwelapha zivame ukwakhiwa ngezinsimbi ezingenasici, njengensimbi engagqwali engu-304 ne-Nitinol, okuqhubeka kube nzima ukushisisa nokwelapha kusengaphambili.Ngokuvamile izimbotshana ezinezingqimba eziningi zisetshenziselwa ukuthola ukunamathela okuhle ku-substrate kusetshenziswa isendlalelo se-binder kanye nejazi eliphezulu elicebile le-fluoropolymer.Yiqiniso, lokhu kwenza inqubo yokufaka isicelo ibe nzima kakhulu ngoba kufanele kusetshenziswe izingqimba eziningi.Kube nentuthuko eminingi emisha yezingubo lapho izinhlelo zejazi elilodwa zithuthukisiwe zinikeza umphumela ofanayo: ukunamathela okuhle ku-substrate kanye ne-topcoat ecebile ye-fluoropolymer.Inqubo yokumboza, nokho, inomthelela omkhulu ekusebenzeni kahle kwale nqubo yokuzihlukanisa.
Isikhathi sokuthumela: Jul-01-2017