Hauv ntau cov txheej txheem kev lag luam thiab cov khoom siv tshwj xeeb, engineers feem ntau ntsib cov lus nug tseem ceeb: cov pa roj carbon nanotubes puas tuaj yeem tiv taus qhov kev pabcuam huab cua? Piv txwv li, siab - kub resistant coatings nyob ib ncig ntawm lub tshuab aerospace, los tiv thaiv - cov kab mob corrosion rau cov tshuaj muaj zog acid thiab alkali reactors, los yog nplaim hluav taws- cov ntaub ntawv retardant rau siab -voltage cables. Cov pa roj carbon nanotubes ruaj khov npaum li cas hauv qhov kub thiab txias / muaj zog acid / muaj zog alkali ib puag ncig? Yog tias cov physicochemical ciam teb no tsis tau to taub meej, ntxiv rau tsis tsuas yog ua tsis tau raws li qhov kev xav tau tab sis kuj tseem tuaj yeem ua rau muaj teeb meem loj hauv engineering. Niaj hnub no, peb yuav siv cov ntaub ntawv sim tiag tiag los qhia qhov ua tau zoo ntawm cov pa roj carbon nanotubes nyob rau hauv cov xwm txheej hnyav.
Siab -Qhov kub siab ruaj khov ntawm Carbon Nanotubes: Oxidation Tsuas yog Achilles 'Heel
Nyob rau hauv inert pa roj los yog lub tshuab nqus tsev ib puag ncig, carbon nanotubes tuaj yeem tiv taus qhov kub siab tshaj 3000 degree. Txawm li cas los xij, hauv cov pa oxygen- muaj huab cua, oxidative decomposition pib tshaj 400℃.
Cov pa roj carbon nanotubes yog tsim los ntawm cov ntshiab sp² carbon-carbon bonds, muab lawv thermal stability siab heev. Txawm li cas los xij, hauv kev siv tswv yim, feem ntau ntawm ib puag ncig muaj oxygen. Qhov tseem ceeb ntawm kev txiav txim siab oxidation tsis kam ntawm cov pa roj carbon nanotubes hauv huab cua yog "qhov tsis xws luag" thiab "graphitization degree" ntawm cov phab ntsa raj. Amorphous carbon impurities thiab carbon atoms ntawm cov qauv tsis xws luag muaj lub zog ntau dua thiab yog qhov nyiam qhov chaw nres rau oxygen ntawm qhov kub thiab txias.
| Carbon Nanotube Hom | Graphitization degree | Pib oxidation kub hauv huab cua (Ti) | Residue Rate ntawm 800℃hauv Cua | Tolerance Kub hauv Inert Gas |
|---|---|---|---|---|
| Crude Multi-Walled Tubes (Low Purity) | Tsawg | ~ 350 degree | >5% (cov ntsiab lus tshauv siab) | 2000 degree |
| High-Purity Multi-Walled Tubes (99%+) | Kwv tij siab | ~ 450 degree | <0.5% | 2500 degree |
| Ib leeg -Ntaus Carbon Nanotubes | Siab heev | ~ 500 degree | <0.1% | >2800 degree |
(Ceeb Toom: Cov ntaub ntawv saum toj no yog raws li ASTM E1131 thermogravimetric ntsuas tus qauv, nrog rau cov cua sov ntawm 10℃/ min hauv huab cua.)
Cov ntaub ntawv qhia tau hais tias yog tias koj daim ntawv thov suav nrog siab -kub oxygen- muaj qhov chaw nyob (xws li siab - kub thermally conductive silicone roj lossis nplaim hluav taws- cov yas retardant), siab - purity carbon nanotubes uas tau dhau los siab -kub yuav tsum tau xaiv kev kho mob. Txwv tsis pub, cov khoom yuav pib "volatilize" ntawm qhov kub siab tshaj 300 degree.
Strong Acid Stability ntawm Carbon Nanotubes: Ib Qhov Ncauj Ob -Edged Sword Effect
Cov pa roj carbon nanotubes yog qhov ruaj khov heev hauv cov pa tsis muaj zog acids. Txawm li cas los xij, nyob rau hauv cov kua qaub uas muaj zog, xws li cov kua qaub sib xyaw nrog cov cua sov, lub kaus mom lub raj thiab cov phab ntsa yuav raug oxidatively txiav, ua rau cov txheej txheem tsis zoo.
Hauv kev hloov khoom siv, peb feem ntau siv cov tshuaj sib xyaw ntawm cov concentrated sulfuric acid thiab concentrated nitric acid (3: 1 los ntawm ntim) rau "acid-ntxuav" carbon nanotubes rau grafting carboxyl pawg. Tab sis qhov no yog qhov tseem ceeb ntawm kev puas tsuaj. Raws li ISO / TS 11308 tus cwj pwm qhia, kev kho cov kua qaub ntev ntev txo qhov sib piv ntawm cov pa roj carbon nanotubes, "txiav" rau hauv cov raj luv luv, ua rau muaj kev poob qis hauv kev ua haujlwm network.
| Ib puag ncig immersion | Kev Kho Mob | Nruab Nrab Ntev Hloov | Surface Functional Group Hloov | Conductive Percolation Threshold Change |
|---|---|---|---|---|
| 10% Dilute Hydrochloric Acid (Room Kub) | 24 teev | Yuav luag tsis hloov | Tsis muaj kev hloov pauv tseem ceeb | Tsis hloov |
| Concentrated Sulfuric Acid (Room Kub) | 48 hnu | Me ntsis luv luv | Ntau cov kab mob hydroxyl pawg | Ntxiv me ntsis |
| Mixed Acid (H₂SO₄:HNO₃) ntawm 80 degree | 2 teev | Shortened ntau dua 70% | Feem ntau ntawm carboxyl / carbonyl pawg | Significantly increased (>3 zaug) |
Yog li ntawd, yog tias koj cov khoom yuav tsum tau ua kom muaj zog acid thaum lub sij hawm tsim khoom (xws li kev kho cov kua qaub da dej rau qee cov fibers tshwj xeeb), ncaj qha ntxiv carbon nanotubes tsis ua tau. Acid-cov txheej txheej tiv taus lossis cov txheej txheem kev hloov kho yuav tsum raug txiav txim siab.
Muaj zog Alkali ruaj khov ntawm Carbon Nanotubes: Ua tau zoo heev
Cov pa roj carbon nanotubes pom muaj zog heev tiv thaiv kom muaj zog alkali ib puag ncig. Txawm tias tom qab ntev - lub sij hawm immersion nyob rau hauv siab - kub concentrated alkali (xws li 40% NaOH), lawv structural morphology thiab hluav taws xob conductivity yuav luag tsis lwj.
Tsis zoo li cov kua qaub muaj zog, sp² carbon network ntawm carbon nanotubes yog ib txwm muaj tshuaj lom neeg rau alkali daws. Hauv tshuaj tiv thaiv - cov coatings coatings thiab muaj zog alkaline roj teeb electrolytes (xws li zinc- roj teeb cua thiab qee lub roj teeb aqueous), carbon nanotubes yog qhov zoo tshaj plaws conductive fillers.
| Kev Xeem | Lub sijhawm immersion | Raman Spectroscopy ID / IG Ratio (Cov yam ntxwv tsis zoo) | Loj poob tus nqi | Conductivity Hloov |
|---|---|---|---|---|
| 40% NaOH (chaw kub) | 720h ua | Tsis muaj kev hloov pauv tseem ceeb | <0.1% | Tsis lwj |
| 40% NaOH (80 degree) | 120 teev | Tsis muaj kev hloov pauv tseem ceeb | <0.2% | Tsis lwj |
| 40% KOH (Room Kub) | 720h ua | Tsis muaj kev hloov pauv tseem ceeb | <0.1% | Tsis lwj |
Qhov no txhais tau hais tias nyob rau hauv thaj chaw muaj zog alkali tiv thaiv- coatings coatings, koj tuaj yeem ntseeg siab siv cov pa roj carbon nanotubes los txhim kho cov tshuaj tiv thaiv - zoo li qub thiab thermal conductivity ntawm txheej, tsis muaj kev txhawj xeeb txog cov khoom siv corrosion lossis degradation.
Shandong Tanfeng Cov Khoom Siv Tshiab: Qhov Chaw Tsim Khoom Kev ntseeg siab rau siab -Kev ruaj ntseg Carbon Nanotubes
Shandong Tanfeng Cov Khoom Tshiab, los ntawm kev txhim kho cov graphitization℃thiab txo qhov tsis xws luag ntawm lub raj phab ntsa, ua kom cov oxidation tsis kam thiab corrosion kuj ntawm carbon nanotubes, ua rau nws nyiam qhov chaw tsim tshuaj paus rau huab ua hauj lwm tej yam kev mob.
Txhawm rau ua kom tiav qhov kawg ntawm cov pa roj carbon nanotubes hauv siab - qhov kub thiab txias ib puag ncig, qhov zoo ntawm cov khoom nws tus kheej yog qhov txiav txim siab. Shandong Tanfeng Cov Khoom Tshiab, los ntawm kev tsim txiaj ntawm nws cov txheej txheem sib xyaw ua ke, ua kom pom qhov zoo:
High -Tsuas Annealing Txheej Txheem, Txhim Kho Oxidation Resistance:Tanfeng Cov Khoom Tshiab qhia txog kev muaj tswv yim siab -kub graphitization annealing kauj ruam tom qab CVD kev loj hlob, kho cov kab mob hauv cov phab ntsa hauv lub raj thiab nce qhov kub ntawm cov pa roj carbon nanotubes hauv huab cua kom siab dua 480 degree, ua tau raws li qhov yuav tsum tau muaj ntawm high -kawg siab {{3}.}cov ntaub ntawv yas thiab thermal conductivity.
Qhov kawg impurity tshem tawm, Txo Acid / Alkali Sensitivity Points:Targeting cov amorphous carbon thiab hlau catalyst residues uas yog feem ntau raug rau tawm tsam nyob rau hauv muaj zog acid / alkali ib puag ncig, Shandong Tanfeng siv ntau yam purification txheej txheem rau stably tswj cov hmoov tshauv nyob rau hauv 0.5%. Tsis muaj impurities "tuav rov qab," qhov kev tiv thaiv corrosion ntawm cov pa roj carbon nanotubes lawv tus kheej raug tso tawm tag nrho.
Huab cua Customized-Resistant Formulations:Rau kev ua haujlwm hnyav, Shandong Tanfeng tsis tsuas yog muab siab - cov hmoov ruaj khov, tab sis kuj muaj cov pa roj carbon nanotube masterbatches nrog kev kho tshwj xeeb ntawm qhov chaw passivation, tiv thaiv cov tshuaj tiv thaiv hauv zos thaum muaj zog acid / alkali ua, muab cov khoom siv ruaj khov rau siab -kawg teb xws li aerospace thiab tshuaj tiv thaiv- corrosion.
Kev ruaj ntseg ntawm cov pa roj carbon nanotubes nyob rau hauv ib puag ncig huab tau nthuav tawm cov qauv tseeb: "zoo heev - kub tsis kam (oxygen- dawb) / zoo heev alkali tsis kam, tab sis raug rau siab - kub oxygen- muaj ib puag ncig thiab muaj zog acid sib xyaw cua sov." Thaum xaiv cov ntaub ntawv, nws yog ib qho tseem ceeb kom phim lawv raws li qhov tseeb ua qhov kub thiab txias ib puag ncig. Yog tias koj tab tom nrhiav rau siab -cov pa roj carbon nanotubes zoo uas tswj cov qauv kev ruaj ntseg raws li kev xav tau ntawm kev ua haujlwm, Shandong Tanfeng Cov Khoom Siv Tshiab, los ntawm kev tsim txiaj ntawm nws cov txiaj ntsig zoo ntawm cov crystallinity siab thiab qhov tsis xws luag, yog qhov tsis txaus ntseeg ntawm tus khub koj tuaj yeem ntseeg tau.