Cov kws tshawb fawb tau tsim cov ntoo dag los ntawm cov khoom siv hluavtaws uas thaum ua cov ntoo zoo nkauj nthuav tawm cov khoom zoo rau kev siv ntau yam..
Ntoo yog ib organic fibrous cov ntaub so ntswg pom nyob rau hauv ntoo, bushes thiab shrubs. Ntoo tuaj yeem hu ua qhov tseem ceeb tshaj plaws thiab tej zaum cov khoom siv ntau yam ntawm ntiaj chaw Lub ntiaj teb. Nws tau siv rau ntau txhiab xyoo rau ntau lub hom phiaj thiab tau hais zoo heev rau nws qhov tsis tshua muaj siab thiab siab zog. Qhov tshwj xeeb anisotropic cellular qauv (xws li cov khoom sib txawv hauv cov lus qhia sib txawv) ntawm cov ntoo muab nws cov khoom siv kho kom zoo nkauj thiab ua rau nws muaj zog, tawv tab sis tseem lub teeb thiab hloov tau. Ntoo muaj lub zog compressive siab thiab tsis tshua muaj zog tensile. Ntoo yog ib puag ncig thiab tus nqi tus phooj ywg, super muaj zog, ruaj khov thiab kav ntev thiab tuaj yeem siv los tsim txhua yam los ntawm kev ua ntawv mus rau tsev.
Xwm tau muab peb cov khoom zoo li ntoo. Txawm li cas los xij muaj ib txwm muaj kev tshoov siab tig mus ncig ntawm qhov xwm txheej rau peb los tsim thiab tsim cov khoom siv biomimetic engineering, uas tuaj yeem 'mimic' cov khoom zoo kawg nkaus ntawm biomaterials twb pom nyob rau hauv qhov. Lub uniqueness ntawm ntoo los ntawm nws cov anisotropic cellular qauv nrog rau tsawg ceev thiab siab zog. Nyob rau yav dhau los cov kws tshawb fawb tsis ntev los no tau sim tsim cov ntaub ntawv xav txog lub tswv yim no hauv kev sib tw rau cov khoom sib xws ntawm cov ntoo zoo li lub zog siab thiab lub teeb. Txawm li cas los xij, feem ntau ntawm kev tshawb fawb tau ua rau cov txiaj ntsig tsis txaus ntseeg vim tias cov ntaub ntawv tsim tau raug kev txom nyem los ntawm ib qho tsis zoo lossis lwm yam. Nws tseem yog qhov nyuaj heev rau cov engineers los tsim dag cov ntaub ntawv zoo li ntoo. Qhov no yog qhov tseem ceeb vim tias nws yuav siv sijhawm ntau xyoo los cog ntoo ntuj thiab lub sijhawm thiab kev ua haujlwm zoo yog qhov muaj zog thaum saib ua cov khoom zoo ib yam li cov ntoo ntuj.
Bioinspired ntoo
Cov kws tshawb fawb los ntawm University of Science thiab Technology ntawm Tuam Tshoj tau tsim ib lub tswv yim tshiab rau fabrication ntawm bioinspired dag polymeric ntoo ntawm qhov loj. Cov khoom siv dag zog no muaj cov ntoo zoo li cov cellular microstructure, zoo controllability nyob rau hauv microstructures thiab yuav ua rau pom cov khoom xws li lightweightness thiab siab zog piv rau txhua yam khoom ntawm ntuj ntoo. Cov kws tshawb fawb hais tias cov khoom siv tshiab no muaj zog zoo li cov ntoo ntuj tsis zoo li lwm cov ntoo uas tau tshawb fawb txog niaj hnub no.
Ntoo pom nyob rau hauv cov xwm muaj ib tug natural polymer hu ua lignin uas yog lub luag hauj lwm ua rau cov ntoo muaj zog. Lignin khi me me crystallites ntawm cellulose ua ke nyob rau hauv ib tug mesh zoo li qauv tsim kom muaj zog. Cov kws tshawb fawb xav txog kev rov ua dua lignin los ntawm kev siv cov khoom siv hluavtaws hu ua resol uas muaj cov khoom zoo sib xws. Lawv tau hloov dua siab tshiab ib txwm muaj resols (phenolic resin thiab melamine resin) rau hauv ntoo dag zoo li cov khoom siv. Kev hloov dua siab tshiab tau ua tiav los ntawm kev siv nws tus kheej ua ke ntawm cov khoom siv polymer thiab tom qab ntawd los ntawm kev siv themocuring. Rau kev ua tiav nws tus kheej, cov khoom siv hluav taws xob ua kom sov yog unidirectionally khov, ces kho (cross-linked los yog polymerized) ntawm qhov kub tsis tshaj 200 degrees Celsius. Cov ntoo engineered tsim tau txais cov qauv ntawm tes zoo li zoo ib yam li cov ntoo ntuj. Tom qab ntawd, thermocuring - ib txheej txheem uas muaj qhov kub thiab txias ntawm cov tshuaj hloov pauv (ntawm no, polymerization) hauv resol - tau ua los tsim cov ntoo hluavtaws polymeric. Qhov pore loj thiab phab ntsa tuab ntawm cov khoom siv no tuaj yeem tswj tau manually. Tsis tas li ntawd xwb, cov crystallites uas resol ua kuj tuaj yeem hloov pauv raws li qhov yuav tsum tau ua ntawm hom ntoo. Cov xim kuj tuaj yeem hloov pauv los ntawm kev ntxiv lossis hloov cov crystallites uas tuav resol ua ke. Thaum cov ntoo engineered no yog compressed, nws nthuav tawm kuj zoo ib yam li nws cov natural counterpart. Txoj hauv kev uas tau piav qhia hauv txoj kev tshawb fawb kuj tseem tuaj yeem raug hu ua txoj hauv kev ntsuab los npaj cov ntoo ntoo uas muaj cov khoom siv nanomaterials xws li cellulose nanofibers thiab graphene oxide tuaj yeem siv.
Interestingly, engineered artificial ntoo qhia zoo corrosion kuj rau dej thiab acid piv rau tej yam ntuj tso ntoo thaum xav tias tsis poob rau hauv nws txhua yam khoom. Qhov no txhais tau hais tias cov ntoo dag tuaj yeem tiv taus huab cua huab cua thiab yuav raug txhim kho thaum muab kev tiv thaiv. Nws kuj qhia tau hais tias thermal rwb thaiv tsev zoo dua thiab txhim kho kev tiv thaiv hluav taws thiab tsis tuaj yeem ntes hluav taws yooj yim xws li ntoo ntuj feem ntau vim hais tias resol yog hluav taws kub retardant. Qhov no tuaj yeem ua rau muaj txiaj ntsig zoo rau cov haujlwm xws li kev tsim khoom thiab kev tsim kho tshwj xeeb tshaj yog cov tsev nyob uas ntes hluav taws thaum tsim siv ntoo. Cov khoom siv yog qhov tsim nyog rau cov tawv nqaij thiab hnyav ib puag ncig raws li nws tau zoo heev thaum piv rau cov ntoo ntuj. Nws yog qhov tshwj xeeb thaum piv rau cov khoom siv engineering xws li cellular ceramics thiab aerogels nrog rau lub zog thiab thermal rwb thaiv tsev. Nws kuj tseem siv tau zoo dua li feem ntau cov yas-ntoo composites vim nws lub zog ntau dua. Cov ntoo engineered muaj ntau ntau yam khoom uas ua rau nws ua haujlwm zoo dua.
Lub tswv yim tshiab tau piav qhia hauv qhov kev tshawb fawb no luam tawm hauv Kev Txhawb Kev Tshawb Fawb muab txoj hauv kev tshiab los tsim thiab engineer ntau yam kev ua haujlwm siab biomimetic engineering cov ntaub ntawv sib xyaw uas yuav muaj qee qhov txiaj ntsig zoo dua lawv cov kev sib tw ib txwm muaj. Cov ntaub ntawv tshiab no tuaj yeem siv dav hauv ntau qhov chaw.
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Qhov (s)
Zhi-Long Y thiab al. 2018 Bioinspired polymeric ntoo. Kev Txhawb Kev Tshawb Fawb. 4 (8).
https://doi.org/10.1126/sciadv.aat7223
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