Cov kws tshawb fawb ntawm Lub Nroog University of Hong Kong (CityU) tau pom ib txoj hauv kev los ua 3D-luam polymer lattice qhov chaw 100 npaug zog dua li ua ntej.
Piv nrog rau cov kev kho cua sov ib txwm siv uas ntxiv dag zog rau cov khoom luam tawm ntawm cov nqi ntawm deformability, CityU txoj hauv kev tsuas yog carbonizes lawv ib nrab los ua kom lawv muaj zog dua thiab ob npaug ntawm cov ductile. Siv lawv cov txheej txheem, pab pawg hais tias, nws muaj peev xwm ua tiav 3D luam ntawv nyuaj nrog cov khoom siv kho tshuab kom haum rau cov kev siv tshwj xeeb, xws li coronary stents lossis bioimplants.
"Nws zoo kawg nkaus uas peb tau pom ib txoj hauv kev los hloov cov 3D luam tawm tsis yooj yim thiab tsis yooj yim rau hauv cov qauv 3D tawv tawv uas sib tw hlau thiab alloys yooj yim los ntawm cua sov rau hauv cov xwm txheej zoo," CityU xibfwb Lu Yang tau hais. "Peb txoj haujlwm muab tus nqi qis, yooj yim, thiab scalable txoj hauv kev los tsim lub teeb yuag, muaj zog, thiab malleable mechanical metamaterials nrog rau txhua qhov geometry."
Chasing "Holy Grail" ntawm cov ntaub ntawv
Raws li CityU cov kws tshawb fawb, kev txhim kho ntawm cov polymer uas yog lub teeb yuag, tsis tau ultra-siab-lub zog thiab ductile tib lub sijhawm yog suav tias yog "dawb grail" ntawm cov ntaub ntawv tshawb fawb thiab kev loj hlob, tab sis cov khoom no feem ntau yog "kev sib koom ua ke".
Qhov no yog vim hais tias pyrolysis, cov txheej txheem feem ntau siv los hloov cov khoom yas rau hauv cov pa roj carbon ntxiv los ntawm cua sov hauv qhov chaw tsis muaj zog, strips yuav luag tag nrho cov deformability ntawm thawj polymer. Thaum pab neeg no lees paub tias muaj lwm txoj hauv kev ntxiv dag zog rau cov yas, lawv hais tias cov no kuj ua rau "qhov brittleness thiab tsis muaj zog" uas "tshem cov qauv siv [ntawm qhov kawg]".
Tshwj xeeb, cov kev tsis txaus siab no txwv kev tsim cov khoom ntawm "metamaterials," uas yog tsim los kom muaj cov khoom tsis pom hauv cov khoom siv raw. Qee qhov kev hloov pauv ntawm cov no tuaj yeem siv los tsim cov micro lattices uas sib xyaw cov qauv tsim qauv nrog cov khoom zoo uas lawv tau ua los ntawm, tab sis cov kws tshawb fawb hais tias lawv cov peev xwm luam ntawv 3D tseem txwv.
"Cov khoom muaj zog thiab tawv tawv feem ntau xav tau hlau lossis alloys rau 3D luam ntawv, tab sis lawv tsis tuaj yeem yooj yim vim yog tus nqi siab thiab kev daws teeb meem ntawm cov lag luam hlau 3D tshuab luam ntawv thiab cov ntaub ntawv raw," Yang ntxiv. "Polymers tau yooj yim dua, tab sis feem ntau tsis muaj zog los yog tawv."
Tsim cov polymers uas yog 100 npaug zog
Hauv cov txheej txheem ntawm kev kawm 3D luam ntawv polymer lattices, pab pawg CityU tau hais tias lawv tau los nrog txoj hauv kev los ua kom sov rau lawv mus rau "magic-like" lub xeev ntawm ib nrab carbonization. Los ntawm kev ua tib zoo tswj tus nqi cua sov, qhov kub thiab txias, lub sijhawm, thiab ib puag ncig ntawm cov pa roj ntawm cov txheej txheem pyrolysis, cov kws tshawb fawb pom tau tias qhov tawv nqaij, lub zog, thiab ductility ntawm micro lattices tuaj yeem nce ntxiv hauv ib kauj ruam.
Cov kws tshawb fawb tau ua qhov kev tshawb pom no los ntawm cov txheej txheem ntawm kev ua tus cwj pwm uas tau qhia tias cua sov qeeb ua rau cov khoom siv polymer chains mus rau qhov kev hloov tsis tiav thaum lub sij hawm hloov pauv pyrolytic. Qhov no tsim cov khoom siv hybrid nyob rau hauv uas structurally reinforced carbon fragments thiab loosely cross-linked polymer chains uas tiv thaiv cov composite los ntawm cracking coexist synergistically.
Los ntawm R & D ntxiv, cov kws tshawb fawb tau mus tshawb pom tias qhov sib piv ntawm cov polymer rau cov pa roj carbon fragments kuj tseem ceeb heev rau kev tsim cov khoom kom zoo rau lub zog thiab ductility. Muab lawv txoj kev xav mus rau qhov kev sim, pab pawg tau tsim ntau qhov kev sim luam tawm uas lawv muaj peev xwm rov tsim kho cov pa roj carbonized lattice uas muaj zog dua 100 npaug thiab ob zaug zoo li qub.
Raws li ib qho ntxiv lawm, cov kws tshawb fawb "hybrid carbon" micro lattices kuj pom zoo biocompatibility dua lawv cov hauv paus polymers thiab txawm tias tau pom tias txhawb nqa cellular bioactivity zoo dua. Nrog rau qhov no hauv siab, pab pawg ntseeg tias lawv cov txheej txheem tuaj yeem siv los nthuav dav kev ua haujlwm ntawm ntau yam ntawm lwm cov polymers thiab qhib cov ntaub ntawv tshiab 3D luam ntawv rau kev kho mob, neeg hlau, thiab cov khoom siv hluav taws xob.
Piv txwv ntawm coronary stents 3D luam tawm los ntawm cov ntaub ntawv carbonized