Mechanism tsom xam ntawm aluminium -dawb siab barrier ntim tshuab

Mechanism tsom xam ntawm aluminium -dawb siab barrier ntim tshuab
Thaum Lub Peb Hlis 25, 2026 Zhongguancun Lub Rooj Sab Laj Txhua Xyoo tau qhib hauv Beijing. Li Xiaohong, Thawj Tswj Hwm ntawm Suav Academy ntawm Engineering, tau tshaj tawm "2025 Ntiaj Teb Engineering Frontier" ntawm qhov qhib ceremony. Lub ntiaj teb engineering frontier nyob rau hauv 2025 yuav qhia plaub lub ntsiab lus tseem ceeb, thiab tag nrho ntawm 94 engineering kev tshawb fawb frontiers thiab 95 engineering kev loj hlob pem hauv ntej yuav raug xaiv nyob rau hauv 9 teb.

Txij li xyoo 2017, Tuam Tshoj Academy ntawm Engineering tau teeb tsa cov kws tshaj lij thiab cov kws tshaj lij los ua cov kev tshawb fawb ntawm "kev tsim kho thoob ntiaj teb kev sib tw" txhua xyoo, thiab tau txais txog 90 engineering kev tshawb fawb frontiers thiab txog 90 engineering kev loj hlob frontiers los ntawm cov ntaub ntawv mining, kev sib cuam tshuam, kev tshawb fawb thiab kev txiav txim siab xaiv raws li 9 cov lus qhia. Cov txiaj ntsig kev tshawb fawb tau luam tawm txhua xyoo ua lus Suav thiab Askiv rau lub ntiaj teb, ua haujlwm zoo ntawm kev qhia kev kawm, kev taw qhia kev lag luam thiab kev txiav txim siab- ua ntaub ntawv siv, thiab tau txais kev saib xyuas thoob plaws thiab kev ntsuam xyuas zoo los ntawm txhua qhov chaw ntawm lub neej hauv tsev thiab txawv teb chaws. Qhov kev tso tawm kev ua tiav no yog thawj zaug uas lub ntiaj teb engineering frontier tau tshwm sim ntawm Zhongguancun Forum

Vim li cas "dealuminization"?

Cov tsoos siab- cov khoom ntim yooj yim (piv txwv li, Tetra Pak ntim, aluminium-cov ntaub ntawv yas) tso siab rau cov ntawv txhuas los yog txhuas plating txheej los muab cov pa oxygen thiab dej vapor teeb meem. Txawm li cas los xij, qhov muaj cov txheej txheem txhuas ua rau muaj teeb meem kev rov ua dua tshiab - cov qauv sib xyaw ntawm txhuas thiab yas thiab cov duab los qhia yog qhov nyuaj rau kev sib cais hauv cov txheej txheem rov ua dua tshiab, thiab ntau tus neeg siv khoom siv rov ua dua tshiab dua li cov khoom siv aluminium - pub dawb. Nyob rau tib lub sijhawm, kev tsim cov txhuas nws tus kheej yog siab - cov txheej txheem hluav taws xob electrochemical, uas yuav tsum tau electrolysis ntawm alumina nyob rau hauv molten cryolite, thiab lub zog efficiency yog txwv los ntawm ntau yam xws li tej zaum thiab sab tshua. Yog li ntawd, txoj kev loj hlob ntawm "aluminium-dawb" siab- cov khoom ntim cov khoom thaiv uas tuaj yeem hloov cov txheej txheem thaiv kev ua haujlwm ntawm txhuas txheej tau dhau los ua cov kev taw qhia tseem ceeb uas coj mus rau hauv kev ua haujlwm thiab kev ruaj khov.

Lub hauv paus ntsiab lus ntawm barrier mechanism

Txhawm rau nkag siab txog txhuas- lwm txoj kev pub dawb, nws yog thawj zaug uas yuav tsum tau ua kom pom tseeb ntawm lub cev ntawm "barrier". Cov txheej txheem ntawm cov pa roj (O2, H2O) dhau los ntawm cov yeeb yaj kiab ua raws li kev sib cais- qauv diffusion: cov roj molecules ua ntej yaj rau ntawm qhov siab - sab ntawm cov yeeb yaj kiab, tom qab ntawd diffuse nyob rau hauv cov polymer matrix uas tau tsav los ntawm cov concentration gradient, thiab thaum kawg desorption ntawm qis - siab sab. Yog li ntawd, muaj ob txoj hauv kev rau lub tswv yim los txo qhov nkag mus:

Txo cov solubility

- Xaiv cov khoom uas tsis tshua muaj affinity nrog lub hom phiaj roj;

Txo qhov diffusion coefficient

- Ua kom lub tortuosity ntawm txoj kev molecular diffusion, lossis txo qhov ntim dawb.

Qhov laj thawj yog vim li cas aluminium foil yog qhov teeb meem tsis tshua muaj vim yog qhov ntom ntom ntom ntom ntawm cov hlau ua rau cov roj diffusion coefficient ze rau xoom. Qhov kev sib tw tseem ceeb ntawm txhuas- cov kev daws teeb meem dawb yog los kwv yees cov txiaj ntsig no nrog cov khoom tsis yog-hlau.

Txoj kev tseem ceeb yog tsis yog -aluminized high barrier technology

1. Polymer barrier khoom txoj kev

EVOH (ethylene-vinyl cawv copolymer) yog ib qho ntawm cov khoom siv txhuas nrov tshaj plaws -dawb thaiv cov ntaub ntawv tam sim no. Lub tshuab yog nyob rau hauv qhov tseeb hais tias pawg hydroxyl -OH nyob rau hauv lub vinyl cawv chav tsev tsim ib tug ntom intermolecular hydrogen daim ntawv cog lus network, uas zoo heev txwv kev txav ntawm polymer saw ntu, ua rau nws nyuaj rau cov pa molecules rau diffuse nyob rau hauv lub matrix. EVOH feem ntau yog siv los ua cov txheej txheem tseem ceeb ntawm ntau- txheej co-extruded qauv thiab yog siv rau hauv ntim aseptic thiab lwm qhov chaw.

PVDC (polyvinylidene chloride) siv qhov loj me thiab polarity ntawm cov tshuaj chlorine atoms kom ua tiav cov saw hlau molecular tsub zuj zuj thiab zoo heev thaiv cov khoom tiv thaiv oxygen thiab dej vapor.

PVA (polyvinyl cawv) coated zaj duab xis yog lwm txoj kev siv tshuab. Cov kev tshawb fawb tau pom tias siab - lub zog thiab siab - thaiv PVA zaj duab xis tuaj yeem tau txais los ntawm txoj kev npaj ntsuab ua ke nrog cov gel extrusion thiab biaxial stretching, uas xav kom dav hloov cov txhuas txheej hauv ntim. Thaum nanoinorganic fillers ntxiv rau PVA, nanoparticles tsim "labyrinth effect" nyob rau hauv matrix, yuam cov roj molecules kom diffuse raws ib tug ntau tortuous txoj kev, ho txhim kho lub barrier kev ua tau zoo.

2. Inorganic oxide evaporation txoj kev

Evaporation ntawm nyias nyias silicon oxide SiOx los yog alumina AlOx nanolayers ntawm PET, BOPP thiab lwm yam substrates yog ib qho kev xaiv rau ncaj qha simulate cov hlau -aluminium barrier mechanism. Lub hauv paus ntsiab lus yog:

Nyias txheej ntawm inorganic oxides (feem ntau tsuas yog ob peb kaum ntawm nanometers tuab) tsim ib tug ntom amorphous iav qauv;

Lub cev dawb ntawm cov qauv no yog nquag me me, thiab cov pa roj diffusion coefficient txo qis;

Tsis zoo li txhuas ntawv ci, SiOx txheej yog pob tshab thiab tsis ua rau cov hlau paug thaum rov ua dua.

Nws yog ib qho tsim nyog sau cia tias huab cua nruj ntawm alumina evaporation txheej yog piv rau cov txheej txheem ntawm silicon oxide, thiab ob qho tib si tuaj yeem npaj los ntawm lub tshuab nqus tsev evaporation lossis plasma-txhim kho cov tshuaj vapor deposition (PECVD) txheej txheem.

3. Cellulose-raws li nanocomposite txoj kev

Cellulose nanomaterials (piv txwv li, nanocellulose siv lead ua CNC, nanocellulose fiber CNF) tau dhau los ua qhov kev tshawb fawb hotspot rau kev ruaj ntseg siab -barrier ntim. Cellulose-raws li cov yeeb yaj kiab hybrid tsim cov txheej txheem zoo rau cov pa oxygen los ntawm kev sib xyaw ntom ntom thiab hydrogen bonding network ntawm nanoscale. Lub mechanism tuaj yeem sau tau raws li:

A["High crystallinity of cellulose nanoparticles"] -->B ["Dense layered accumululation txo cov ntim dawb"]

B -->C ["Hydrogen bond network txwv cov saw segment motion"]

C -->D ["Twisted diffusion path extends gas penetration path"]

D -->E ["Hyperoxia barrier kev ua tau zoo"]

Qhov zoo ntawm txoj kev no yog tias cov khoom siv raw yog muab los ntawm cov khoom siv txuas ntxiv dua tshiab thiab cov khoom lag luam yog biodegradable lossis yooj yim recyclable.

4. Multi-txheej co-extrusion composite zoo

Cov ntaub ntawv no feem ntau yuav tsum tau siv ua ke nrog cov ntaub ntawv polyolefin nrog zoo heev kub sealing thiab ya raws. Qhov tseeb aluminium-dawb siab barrier ntim feem ntau yog ntau- txheej co-extrusion qauv nrog 5 ~ 9 txheej, qhov twg:

Hierarchy

Muaj nuj nqi

Yam khoom siv

Txheej txheej

Printability, mechanical zog

PEB, PET

Barrier txheej

Oxygen / dej vapor barrier

EVOH, PVDC, SiO
x
Plating

Bonding txheej

Kev sib xyaw ntawm interlayer

Maleic anhydride grafted polyolefin

Sab hauv txheej

Thaum tshav kub kub sealing, zaub mov tiv thaiv kev nyab xeeb

PEB, CPP

Cov txheej txheem txheej txheem ntawm cov txheej txheem multilayer no yog kev sib koom ua ke - qhov cuam tshuam ntawm txhua txheej yog superimposed ntawm tus qauv tandem, thiab tag nrho cov permeability qis dua li ntawm ib txheej ntawm cov khoom.

Lub mechanism logic ntawm qhov rov qab kom zoo dua

Qhov zoo ntawm aluminium-dawb tsim nyob rau sab rov ua dua los ntawm kev yooj yim ntawm cov khoom siv. Cov teeb meem tseem ceeb uas tau ntsib los ntawm cov tsoos txhuas- cov khoom ntim yas sib xyaw hauv kev rov ua dua yog qhov ntom ntom ntawm aluminium thiab yas yog nyob ze thiab daim ntawv cog lus muaj zog, thiab cov nqi sib cais yog siab. Aluminium-cov kev daws teeb meem dawb, xws li tag nrho -polymer multilayer structures lossis oxide-coated structures, tuaj yeem ua kom tau txais txiaj ntsig zoo dua los ntawm:

Tag nrho cov qauv polymer: tuaj yeem ncaj qha yaj thiab rov ua dua, tsis tas yuav tsum muaj cov kauj ruam sib cais;

Oxide txheej: Cov txheej txheej yog nyias nyias (nano{0}} nplai), uas tsis cuam tshuam rau kev ua kom zoo ntawm cov substrate thaum lub sijhawm rov ua dua.

Cellulose-raws li kev daws teeb meem: compostable thiab tag nrho tawm ntawm cov yas rov ua dua kwj.

Txawm li cas los xij, kev ntsuas kev ntsuas lub neej nyob rau hauv cov cheeb tsam xws li cov roj teeb tshiab kuj tseem ceeb rau peb tias cov txiaj ntsig ib puag ncig ntawm cov khoom siv tshiab yuav tsum tau soj ntsuam thoob plaws hauv cov saw hlau, suav nrog kev siv hluav taws xob thiab emissions thaum lub sijhawm tsim khoom.

Summary and Limitations

Cov txheej txheem tseem ceeb ntawm txhuas- pub dawb siab- ntim khoom thaiv yog txhawm rau txo cov roj permeability hauv cov kev sib txuas tseem ceeb ntawm kev sib cais- cov txheej txheem diffusion los ntawm cov tsis yog -hlau txhais tau tias xws li polymer hydrogen bond network, inorganic oxide ntom txheej, thiab nanofiller tortuous nyhuv, thaum yooj yim rov qab cov ntaub ntawv.

Nws yuav tsum raug sau tseg tias cov ntaub ntawv khaws cia tam sim no tau txwv tsis pub tshaj tawm cov ncauj lus no, thiab cov lus piav qhia saum toj no ntawm cov txheej txheem ntawm cov khoom thaiv tshwj xeeb (EVOH, PVDC, thiab lwm yam) ib nrab tso siab rau kev paub txog cov khoom siv dav dav es tsis yog kev txhawb nqa ncaj qha los ntawm cov ntaub ntawv tshwj xeeb. Yog tias koj xav tau kom nkag siab tob dua ntawm txoj hauv kev tshwj xeeb (xws li SiOx evaporation txheej txheem tsis, thaiv kev cuam tshuam ntawm EVOH hauv cov av noo ib puag ncig, thiab lwm yam), nws raug nquahu kom tshawb nrhiav cov ntaub ntawv tseem ceeb ntxiv . ...