Cov kws tshawb fawb tau tsim cov yas sib npaug rau cov hlau - muaj zog tab sis tsis hnyav.Plastics, uas qee zaum chemists hu ua polymers, yog ib chav kawm ntawm cov saw ntev molecules ua los ntawm cov luv luv rov ua dua tshiab hu ua monomers.Tsis zoo li yav dhau los polymers ntawm tib lub zog, cov khoom tshiab tsuas yog los ntawm daim nyias nyias.Nws tseem yog 50 npaug ntau airtight tshaj qhov feem ntau impermeable ntawm cov yas no tsis yog cov khoom siv polymer. synthesis.Cov txheej txheem, uas yuav siv sij hawm qhov chaw nyob rau hauv lub chav tsev kub, yuav tsum tau tsuas yog pheej yig cov ntaub ntawv, thiab cov polymer muaj peev xwm yuav loj-tsim nyob rau hauv loj nplooj ntawv uas tsuas yog nanometers tuab.Cov kws tshawb fawb qhia lawv cov kev tshawb pom Feb 2 nyob rau hauv phau ntawv journal Nature.
Cov khoom hauv nqe lus nug yog hu ua polyamide, cov xov sib txuas ntawm amide molecular units (amides yog cov tshuaj lom neeg nitrogen txuas nrog oxygen-bonded carbon atoms). Cov polymers xws li Kevlar, fiber ntau siv los ua cov tsho tiv thaiv mos txwv, thiab Nomex, cov ntaub tiv thaiv hluav taws. Zoo li Kevlar, polyamide molecules nyob rau hauv cov khoom tshiab yog txuas mus rau tag nrho cov saw hlau uas muaj zog ntawm hydrogen. khoom.
"Lawv lo ua ke zoo li Velcro," tus kws sau ntawv Michael Strano, tus kws tshaj lij tshuaj tshuaj MIT tau hais.Tearing cov ntaub ntawv yuav tsum tsis yog tsuas yog rhuav tshem cov saw hlau molecular xwb, tab sis tseem kov yeej cov kev sib tshuam loj heev ntawm hydrogen bonds uas permeate tag nrho cov khoom polymer.
Tsis tas li ntawd, cov polymers tshiab tuaj yeem ua cov flakes.Qhov no ua rau cov khoom siv tau yooj yim, raws li nws tuaj yeem ua rau hauv cov yeeb yaj kiab nyias lossis siv los ua cov yeeb yaj kiab nyias txheej txheej.Traditional polymers zoo li loj hlob raws li cov kab sib txuas, lossis txuas ntxiv ceg thiab txuas hauv peb qhov ntev, tsis hais txog kev taw qhia.Tab sis Strano cov polymers loj hlob hauv ib txoj hauv kev tshwj xeeb hauv daim ntawv 2D.
"Koj puas tuaj yeem sib sau ua ke ntawm ib daim ntawv? Nws hloov tawm, feem ntau, koj ua tsis tau kom txog thaum peb ua haujlwm," Strano hais. "Yog li, peb nrhiav tau ib lub tswv yim tshiab." Hauv kev ua haujlwm tsis ntev los no, nws pab neeg tau kov yeej qhov teeb meem los ua kom muaj kev sib sau ua ke ob sab.
Yog vim li cas polyaramides muaj cov qauv qauv yog tias polymer synthesis koom nrog cov txheej txheem hu ua autocatalytic templating: raws li cov polymer lengthens thiab sticks rau monomer lub tsev blocks, cov polymer loj hlob induces tom ntej monomers kom tsuas yog sib xyaw ua ke nyob rau hauv txoj kev coj los ntxiv dag zog rau lub union ntawm ob.dimensional qauv.Cov kws tshawb fawb pom tau hais tias lawv muaj peev xwm tsim cov tshuaj polymers nyob rau hauv ib qho yooj yim. laminates tsawg dua 4 nanometers tuab.Qhov ntawd yog yuav luag ib lab lub thickness ntawm cov ntawv ua haujlwm li niaj zaus.
Txhawm rau kom muaj nuj nqis ntawm cov khoom siv ntawm cov khoom siv polymer, cov kws tshawb fawb tau ntsuas lub zog yuav tsum tau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm txheej txheej ntawm cov hlau, xws li tsheb veneers, los yog lim dej kom huv.Nyob rau hauv lub tom kawg muaj nuj nqi, lub zoo tagnrho lim membrane yuav tsum nyias nyias tab sis muaj zog txaus los tiv thaiv high pressures tsis to me me, tsis muaj paug paug rau peb zaum kawg mov - ib tug zoo meej haum rau cov khoom siv polyamide.
Nyob rau yav tom ntej, Strano vam tias yuav txuas ntxiv cov txheej txheem polymerization rau cov polymers sib txawv tshaj qhov Kevlar analog. "Polymers nyob ib puag ncig peb," nws hais tias "Lawv ua txhua yam." Xav txog kev hloov pauv ntau yam ntawm cov polymers, txawm tias cov kab txawv uas tuaj yeem ua hluav taws xob lossis lub teeb, ua cov yeeb yaj kiab nyias uas tuaj yeem npog ntau qhov chaw, nws hais ntxiv.
Hauv lub ntiaj teb uas nyob ib puag ncig los ntawm cov yas, tib neeg muaj laj thawj txaus siab rau lwm cov polymer tshiab uas nws cov khoom siv yog dab tsi tab sis zoo tib yam, Strano hais tias aramid yog qhov ruaj khov heev, uas txhais tau hais tias peb tuaj yeem hloov cov yas niaj hnub, los ntawm cov xim rau lub hnab mus rau cov khoom ntim khoom noj, nrog cov ntaub ntawv tsawg dua thiab muaj zog dua.Strano ntxiv tias los ntawm qhov kev ruaj ntseg, qhov no super-strong 2D polymer yog ib kauj ruam ntawm lub ntiaj teb no.
Shi En Kim (raws li nws feem ntau hu ua Kim) yog tus kws sau ntawv ywj pheej ntawm Malaysian yug thiab Nrov Science Spring 2022 editorial intern.Nws tau sau ntau yam ntawm cov ncauj lus xws li kev siv cov cobwebs-tib neeg lossis kab laug sab lawv tus kheej-rau cov neeg khaws khib nyiab hauv qhov chaw sab nrauv.
Boeing's Starliner spacecraft tseem tsis tau mus txog qhov chaw nres tsheb thoob ntiaj teb, tab sis cov kws tshaj lij tau pom zoo txog qhov kev sim thib peb.
Peb yog ib tus neeg koom nrog Amazon Services LLC Associates Program, ib qho kev koom tes tshaj tawm kev tshaj tawm tsim los muab txoj hauv kev rau peb kom tau txais cov nqi los ntawm kev txuas mus rau Amazon.com thiab cov chaw koom nrog. Kev sau npe lossis siv lub vev xaib no suav nrog kev lees txais peb Cov Cai Kev Pabcuam.
Post lub sij hawm: May-19-2022