Ososayensi benze ukhuni lokwenziwa ngezinhlaka zokwenziwa okuthi ngenkathi belingisa ukhuni lwemvelo babonise izakhiwo ezithuthukisiwe ukuze zisetshenziswe emisebenzini eminingi.
Izinkuni kuyinto eziphilayo izicubu ezine-fibrous ezitholakala ezihlahleni, ezihlahleni nasezihlahleni. Izinkuni zingabizwa njengezinto eziwusizo kakhulu futhi mhlawumbe eziguquguqukayo kakhulu planet Umhlaba. Isetshenziswe izinkulungwane zeminyaka ngezinjongo eziningi futhi iphawuleka kakhulu ngokuminyana kwayo okuphansi namandla ayo aphezulu. Isakhiwo esiyingqayizivele samangqamuzana e-anisotropic (okungukuthi izakhiwo ezihlukene ngezindlela ezihlukene) zokhuni zisinika izici ezimangalisayo zomshini futhi zilenze liqine, liqine kodwa libe lilula futhi liguquguquke. Izinkuni zinamandla acindezelayo aphezulu namandla aphansi okuqina. Ukhuni luyimvelo futhi alubiza kakhulu, luqine kakhulu, luqinile futhi luhlala isikhathi eside futhi lungasetshenziselwa ukwakha noma yini kusukela ekwenzeni iphepha kuye ekwakheni izindlu.
Imvelo isivele isinikeze izinto ezimangalisayo njengokhuni. Nokho kuhlale kukhona ugqozi oluzungeza imvelo ukuze sidizayine futhi sithuthukise izisetshenziswa zobunjiniyela be-biomimetic ezisebenza kahle kakhulu, ezingase 'zilingise' izici ezimangalisayo ze-biomaterials esezitholakala emvelweni. Ukuhluka kokhuni kuvela esakhiweni salo samangqamuzana e-anisotropic kanye nokuminyana okuphansi namandla aphezulu. Esikhathini esidlule ososayensi baye bazama ukuklama izinto ezicabangela lo mqondo emzamweni wokuphindaphinda izakhiwo zokhuni ezifana nokuqina okuphezulu nokulula. Kodwa-ke, ucwaningo oluningi luye lwaholela emiphumeleni engagculisi njengoba izinto eziklanyelwe zihlushwa iphutha elilodwa noma elinye. Kuseyinselelo enkulu konjiniyela ukwakha yokufakelwa izinto ezifana nezinkuni. Lokhu kubaluleke kakhulu ngoba kuthatha amashumi eminyaka ukukhulisa izinkuni zemvelo kanye nesikhathi nokusebenza kahle kuyisici esiqinile lapho ubheka ukwenza into efana nezinkuni zemvelo.
Ukhuni lwe-Bioinspired
Abacwaningi abavela eNyuvesi Yesayensi Nobuchwepheshe YaseChina baklame isu elinoveli lokwenziwa kwe-polymeric yokwenziwa ye-bioinspired izinkuni ngezinga elikhulu. Le nto yokwenziwa ine-microstructure yeselula efana nokhuni, ilawuleka kahle kuma-microstructures futhi ingabonisa izakhiwo ezifana nokukhanya namandla aphezulu afana nezakhiwo zemishini zokhuni lwemvelo. Abacwaningi bathi le nto entsha iqine njengokhuni lwemvelo ngokungafani nanoma yiziphi ezinye izinkuni zobunjiniyela ezicwaningiwe kuze kube manje.
Ukhuni olutholakala emvelweni luqukethe i-polymer yemvelo ebizwa ngokuthi i-lignin enesibopho sokwenza ukhuni luqine. I-Lignin ibopha amakristalu amancane e-cellulose ndawonye esakhiweni esinjenge-mesh ukuze kwakhe amandla aphezulu. Abacwaningi bacabange ukuphindaphinda i-lignin ngokusebenzisa i-polymer yokwenziwa ebizwa ngokuthi i-resol enezici ezifanayo. Baguqule ngempumelelo ama-resols atholakala ngokwesiko (phenolic resin kanye ne-melamine resin). izinkuni zokwenziwa njengempahla. Ukuguqulwa kwafinyelelwa ngokuqala kusetshenziswa izakhiwo zokuzihlanganisa ze-polymer resol bese ngokusebenzisa i-themocuring. Ukuze kuzuzwe ukuzihlanganisa, ama-resin e-thermostat ewuketshezi ayeqandiswe ngendlela engaqondile, bese ephulukiswa (exhunywe ngokuphambana noma enziwe i-polymerized) emazingeni okushisa angekho ngaphezu kwama-degrees Celsius angama-200. Ukhuni olwakhiwe ngobunjiniyela luthatha isakhiwo esifana neseli esicishe sifane nokhuni lwemvelo. Kamuva, i-thermocuring - inqubo ehlanganisa ukuguqulwa kwamakhemikhali okubangelwa izinga lokushisa (lapha, i-polymerization) ku-resol - yenziwa ukukhiqiza izinkuni ze-polymeric zokwenziwa. Ubukhulu bembotshana nokuqina kodonga lwento enjalo ingalawulwa ngesandla. Hhayi lokho kuphela, ama-crystallites enziwa i-resol nawo angashintshwa ngokuya ngesidingo sohlobo lokhuni. Umbala ungase futhi ushintshwe ngokungeza noma ukushintsha amakristalu abamba i-resol ndawonye. Lapho lolu godo olubunjiniyela lucindezelwa, lubonisa ukumelana okufana nozakwabo wemvelo. Indlela echazwe ocwaningweni ingabuye ibizwe ngokuthi indlela eluhlaza yokulungisa izinkuni zokwenziwa lapho kungasetshenziswa khona umquba wama-nanomaterials njengama-cellulose nanofibers kanye ne-graphene oxide.
Kuyathakazelisa ukuthi ukhuni lokwenziwa olunjiniyela lubonisa ukumelana nokugqwala okungcono emanzini ne-asidi uma kuqhathaniswa nokhuni lwemvelo kuyilapho lungathathi ukwehla ezicini zalo eziwumshini. Lokhu kusho ukuthi izinkuni zokwenziwa zingamelana nezimo zezulu ezimbi kakhulu futhi zingathuthukiswa ekunikezeni ukuvikeleka. Iphinde ibonise ukugqugquzelwa kokushisa okungcono nokumelana nomlilo okuthuthukisiwe futhi ngeke ibambe umlilo kalula njengoba kwenza ukhuni lwemvelo ikakhulukazi ngoba i-resol ibamba umlilo. Lokhu kungaba usizo emikhakheni efana nokukhiqiza nokwakha ikakhulukazi izakhiwo zokuhlala ezivutha umlilo uma zakhiwe kusetshenziswa izinkuni zemvelo. Impahla ifaneleka kahle ezindaweni eziqinile neziqinile njengoba ithuthukiswa kakhulu uma iqhathaniswa nokhuni lwemvelo. Ihlukile uma iqhathaniswa nezinto ezijwayelekile zobunjiniyela ezifana ne-ceramics yeselula nama-aerogels ngokuphathelene namandla kanye nezakhiwo zokuvikela ukushisa. Iphinde isebenze kakhulu kunezinhlanganisela eziningi zokhuni lwepulasitiki ngenxa yamandla ayo aphezulu. Ukhuni olwakhiwe lunenqwaba yezinto ezilwenza lusebenze kahle.
Isu inoveli echazwe kulolu cwaningo eshicilelwe ngo Ukuthuthukiswa Kwezesayensi inikeza izindlela ezintsha zokwenza kanye nonjiniyela izinhlobonhlobo zezinto eziyinhlanganisela zobunjiniyela be-biomimetic ezisebenza kahle ezizoba nenzuzo enkulu kunozakwabo bendabuko. Izinto ezinjalo zamanoveli zingasebenza kabanzi emikhakheni eminingi.
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{Ungafunda iphepha lokuqala locwaningo ngokuchofoza isixhumanisi se-DOI esinikezwe ngezansi ohlwini lwemithombo ekhonjiwe}
Umthombo (s)
Zhi-Long Y at al. 2018 Bioinspired polymeric izinkuni. Ukuthuthukiswa Kwezesayensi. 4(8).
https://doi.org/10.1126/sciadv.aat7223
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