Cov kev hloov hauv micromorphology thiab cov ntsiab lus tseem ceeb ntawm cov qauv asphalt
Oct 19, 2022
Thov hu rauoscar.xiao@wecistanche.comyog xav paub ntxiv
Abstract:Txhawm rau txo cov thermal-oxidative kev laus ntawm asphalt thiab tso tawm tus nqi ntawm cov teeb meem volatiles thaum lub sij hawm kev tsim kho ntawm asphalt pavement, ib tug tshiab composite anti-aging tus neeg sawv cev tau tsim. Txij li thaum cov volatiles raug tso tawm tsuas yog los ntawm saturates thiab aromatics thaum lub sij hawm thermal-oxidative laus ntawm asphalt, nthuav graphite (EG) raug xaiv los ua tus neeg sawv cev ruaj khov rau thauj magnesium hydroxide (MH) thiab calcium carbonate (CaCO3) nanoparticles rau kev npaj cov kev laus. Cov neeg sawv cev ntawm saturates thiab aromatics, feem. Thermal stability thiab volatile constituents tso tawm los ntawm saturates thiab aromatics ua ntej thiab tom qab lub thermal-oxidative aging tau characterized siv lub isothermal Thermogravimetry/Differential Scanning Calorimetry-Fourier Transform Infrared Spectrometer test (TG/DSC-FTIR test).cistanche UKCov txiaj ntsig kuaj pom tau hais tias cov tshuaj tiv thaiv kev laus ntawm EG / MH thiab EG / CaCO, muaj txiaj ntsig zoo cuam tshuam cov volatilization ntawm lub teeb hauv asphalt thiab txhim kho thermal stability ntawm saturates thiab aromatics. Tom qab ntawd, qhov kev faib ua feem ntawm EG, MH, thiab CaCO; ntxiv nyob rau hauv cov tsim composite anti-aging tus neeg sawv cev ntawm EG / MH / CaCO3 yog 2: 1: 3 los ntawm qhov hnyav. EG/MH/CaCO plays ib tug synergetic nyhuv ntawm inhibiting lub thermal-oxidative laus ntawm asphalt, thiab txo qhov tso tawm ntawm cov teeb meem volatiles thaum lub thermal-oxidative laus tom qab EG/MH/CaCO; yog ntxiv rau hauv asphalt ntawm cov ntsiab lus ntawm 10 wt. feem pua. plays lub luag hauj lwm sib koom ua ke nrog MH thiab CaCO, nanoparticles los tiv thaiv cov saw kev cuam tshuam, inhibiting thermal-oxidative aging ntawm asphalt.
Ntsiab lus:asphalt; thermal-oxidative kev laus; composite anti-aging agent; volatile constituents; cov nyhuv synergistic
Thov nias ntawm no kom paub ntxiv
1. Taw qhia
Asphalt yog ib qho sib xyaw ntawm hydrocarbon thiab non-hydrocarbon compounds nrog cov khoom nyuaj heev. Asphalt yog ib qho ntawm cov khoom siv dav siv ntau tshaj plaws rau kev tsim vaj tsev nyob hauv Suav teb. Txawm li cas los xij, nws yog qhov yooj yim rau kev laus thaum lub sij hawm tsim kho thiab kev pab cuam lub neej ntawm asphalt pavement. Thaum raug tshav kub, tshav ntuj, oxygen, thiab noo noo, asphalt yuav nyuaj, ua rau muaj kev nyuaj siab ntawm txoj kev taug kev xws li tawg, raveling, potholes, thiab lwm yam. [1]. Ntxiv mus; qhov tso tawm volatile organic tebchaw muaj teeb meem rau ib puag ncig ntuj thiab kev tsim kho cov neeg ua haujlwm kev noj qab haus huv thaum thermal-oxidative cov tshuaj tiv thaiv ntawm asphalt tshwm sim ntawm qhov kub siab [2]. Thermal-oxidative laus muaj nyob rau hauv kev tsim kho thiab kev pabcuam ntawm asphalt pavement, suav nrog kev sib xyaw, paving, dov, thiab kev pabcuam theem [3,4]. Yog li, qee cov tshuaj tiv thaiv kev laus tau tsim los ua kom lub neej ntev kev pab cuam ntawm asphalt pavement. Qee qhov kev siv zog kuj tau ua los txhim kho kev laus ntawm asphalt los ntawm kev ntxiv ntau yam hloov pauv. Kev txhim kho ntawm cov neeg ua haujlwm tiv thaiv kev laus feem ntau yog txiav txim siab los ntawm qhov pom ntawm cov tshuaj tiv thaiv antioxidants, lub teeb stabilizers, thiab cov cua sov stabilizers [5,6]. Cov pa roj carbon dub, montmorillonite, antioxidant, ib qho ultraviolet absorber (UVA), thiab lwm yam. feem ntau yog siv los ua additives los inhibit lub thermal- thiab photo-oxidative laus ntawm asphalt [6]. Cov khoom siv ntau yam nanomaterial uas muaj cov txheej txheem inorganic silicates tau siv los ua kom zoo dua thermal- thiab photo-oxidative aging kuj [7,8]. Zare-Shahabadi et al. [9] pom tias qhov sib ntxiv ntawm nanoclay nce viscosity ntawm asphalt, thiab txhim kho kev tiv thaiv kev laus, tiv thaiv rutting, thiab tiv thaiv qaug zog ntawm asphalt. Tsis ntev los no, EG tau them nyiaj ntau dua vim tias nws yog hom tshiab ntawm cov khoom siv carbon mesoporous thiab muaj ntau dua cov cua sov hloov thiab adsorption zog [10]. Thaum muab piv nrog lwm cov adsorbents, EG qhia tau hais tias muaj peev xwm ua tau zoo dua rau adsorb thiab kho cov roj vim nws cov qauv ntxeem tau, nrog rau kev ua kom sov zoo thiab kev ua haujlwm loj [11-13].cistanche wrkungYog li ntawd, EG tuaj yeem cuam tshuam zoo dua hauv aromatics, saturates, thiab asphalt. Tsis tas li ntawd, EG yog ib qho yooj yim rau adsorb roj thiab cov organic me me molecules, uas yog haum rau siv raws li cov cab kuj ntawm anti-aging agents ntawm saturates thiab aromatics [11]. Tsis tas li ntawd, nws paub tias yam tsawg kawg ib qhov ntev ntawm nanomaterial yog nyob rau hauv ib tug nanoscale ntau ntawm 1-100 nm. Qhov piv ntawm tus naj npawb ntawm atoms rau tag nrho cov atoms nyob rau saum npoo ntawm nanocrystalline particles nce sharply nrog qhov txo ntawm particle loj, uas ntxiv ua rau kev hloov ntawm cov khoom siv [14]. Nyob rau hauv xyoo tas los no, ntau inorganic nanomaterials tau siv los ua asphalt modifiers [14,15]. MH thiab CaCO nanoparticles feem ntau tau siv los txhim kho thermal stability ntawm cov ntaub ntawv polymer [16-18].
Cistanche tuaj yeem tiv thaiv kev laus
Lub MHnanoparticle, raws li ib yam ntawm cov nplaim hluav taws muaj txiaj ntsig zoo, muaj zog thermal stability thiab cov pa taws tua hluav taws [19,20]. MH nanoparticles qhia lub ntim nyhuv thiab quantum loj nyhuv tom qab nano crystallization, uas txhim kho kev sib raug zoo ntawm MH thiab asphalt. MH kuj muaj qee yam adsorption nyhuv [21-23]. Tsis tas li ntawd, MH yog alkaline, uas tuaj yeem tsis tsuas yog ua lub luag haujlwm hauv kev sau, adsorption, thiab txhim kho cov thermal stability tab sis kuj neutralize qee cov kua qaub los yog cov khoom gaseous, xws li -COOH, SO2, thiab lwm yam. [24]. Wu et al[25] ntxiv MH rau hauv cov khoom siv fiber ntau hauv ntuj, thiab pom tias MH tau txhim kho kev sib raug zoo ntawm fibers thiab polymer matrix, txhim kho cov dej noo-kev puas tsuaj thiab cov khoom siv ntawm cov khoom sib xyaw, thiab ua rau cov txheej txheem kev laus. Zhu et al. [26] siv MH los hloov kho lub microporous polymer nanotube rau kev txhim kho nws cov thermal stability thiab tau tshaj tawm tias hloov kho microporous polymer nanotubes muaj peev xwm siv tau zoo raws li kev cog lus thermal rwb thaiv tsev cov khoom rau thermal txuag hluav taws xob.
Nano CaCO: muaj thermal stability ntau dua, thiab spatial stereoscopic qauv, kom nws muaj zoo dispersity nyob rau hauv cov ntaub ntawv polymeric [24, 26-28]. Raws li cov ntaub ntawv dhau los, qhov sib ntxiv ntawm CaCO, nanoparticles tuaj yeem txhim kho cov thermal stability thiab mechanical zog ntawm cov polymer [29].Citrus bioflavonoidsTsis tas li ntawd, qhov chaw ntawm cov active nano CaCO3 yog oleophilic thiab hydrophobic, thiab nws muaj kev sib raug zoo nrog cov roj Cheebtsam, uas yuav ua tau zoo los yog kho cov rheological zog ntawm asphalt [24]. Nazarite al[14] pom tias kev tiv thaiv kev laus ntawm asphalt tau txhim kho los ntawm kev ntxiv CaCO3 nanoparticles, thiab CaCO cov ntsiab lus cuam tshuam rau cov khoom qaug zog ntawm kev hloov kho asphalt. Xing et al. [30] ua pov thawj tias CaCO; nanoparticles txhim kho lub siab-kub stability thiab anti-rutting peev xwm ntawm asphalt los ntawm txawv qhov cuab lub zog. Zhai et al. [18] taw qhia tias asphalt hloov los ntawm 5 wt. feem pua nano CaCO3 thiab 4 wt. feem pua SBR modifier muaj superior anti-rutting thiab creep yam ntxwv ntawm qhov kub thiab txias thaum piv nrog rau SBS hloov asphalt. Tam sim no, feem ntau tsim los tiv thaiv kev laus ntawm asphalt yog tsom rau ultraviolet kev laus los yog kev laus mus sij hawm ntev hauv ib puag ncig ntuj tab sis tsis quav ntsej qhov cuam tshuam ntawm lub sij hawm luv luv thermal-oxidative aging ntawm kev ua haujlwm ntawm asphalt pavement thiab cov neeg ua haujlwm noj qab haus huv ntawm kev tsim kho. theem. Tsis tas li ntawd, txawm hais tias muaj qee yam tshuaj tiv thaiv kev laus kom txo tau cov thermal-oxidative aging ntawm asphalt, ob peb cov tshuaj tiv thaiv kev laus tau tsim los ntawm cov volatilization ntawm saturates thiab aromatics thaum tsim kho asphalt pavement. Thaum kawg, tus neeg sawv cev tiv thaiv kev laus tsim los txo qis thermal-oxidative kev laus ntawm asphalt yog ib leeg, thiab tsis sib xyaw ua ke raws li cov khoom siv thermal thiab cov ntsiab lus ntawm saturates thiab aromatics ntawm qib tivthaiv.
Raws li peb cov kev tshawb fawb yav dhau los [31], cov teeb meem tsis zoo ntawm asphalt feem ntau yog tsim los ntawm aromatics thiab saturates vim thermal-oxidative kev laus thaum lub sij hawm tsim kho ntawm asphalt pavement, ua rau muaj kev cuam tshuam tsis zoo rau ecological ib puag ncig thiab cov neeg ua haujlwm noj qab haus huv. Yog li, lub hom phiaj ntawm txoj kev tshawb no yog thawj zaug xaiv cov tshuaj tiv thaiv kev laus rau cov tshuaj tsw qab thiab cov saturates raws li lawv cov khoom siv thermal thiab tso tawm cov neeg tsis muaj zog, raws li, thiab tom qab ntawd xaiv cov tshuaj tiv thaiv kev laus yog sib xyaw ua ke raws li cov ntsiab lus ntawm aromatics thiab saturate nyob rau hauv asphalt. Yog li, tus neeg sawv cev tshiab los tiv thaiv kev laus rau cov khoom siv asphalt yog tsim los txhim kho cov thermal stability thiab txo cov thermal-oxidative aging ntawm asphalt, txo qhov tso tawm ntawm volatiles thaum lub sij hawm tsim kho ntawm asphalt pavement. Hauv txoj kev tshawb no, MH thiab CaCO3 nanoparticles tau xaiv thawj zaug los ua cov tshuaj tiv thaiv kev laus ntawm saturates thiab aromatics, feem, txhim kho lawv cov thermal stability thiab txo qhov tso tawm ntawm volatiles. Tom qab ntawd, EG tau raug xaiv los ua tus neeg nqa khoom ntawm MH thiab CaCO: nanoparticles, thiab tseem adsorbed thiab tsau lub teeb gaseous khoom tso tawm los ntawm saturates thiab aromatics hauv asphalt. Tom qab ntawd, EG / MH thiab EG / CaCO3 tau ntxiv rau hauv saturates thiab aromatics raws li lawv cov tshuaj tiv thaiv kev laus, feem. Cov txheej txheem thermal-oxidative aging ntawm saturates thiab aromatics tau txhawb nqa los ntawm isothermal TG / DSC-FTIR test. Cov teebmeem ntawm EG/MH thiab EG/CaCO3 ntawm qhov thermal stability thiab tso tawm tsis muaj zog ntawm cov saturates thiab aromatics tau tham los ntawm TG/DSC-FTIR cov qhabnias xeem.
Tsis tas li ntawd, cov tshuaj tiv thaiv kev laus ntawm EG / MH / CaCO3 tau tsim los ntawm kev ua haujlwm inhibitory ntawm EG / MH thiab EG / CaCO3 ntawm thermal-oxidative aging ntawm saturates thiab aromatics. EG/MH/CaCO3 tau ntxiv rau qhov zoo asphalt thiab isothermal TG/DSC-FTIR test yog siv los txhawb lub sij hawm luv luv thermal-oxidative aging ntawm asphalt. Thaum kawg, qhov cuam tshuam ntawm kev tsim cov tshuaj tiv thaiv kev laus ntawm EG / MH / CaCO3 ntawm thermal stability, volatile emission, morphology, thiab elemental cov ntsiab lus ntawm asphalt tau tus cwj pwm siv isothermal TG / DSC-FTIR thiab (Environment Scanning Electric Microscope-Energy. Disperse Spectroscopy test) ESEM-EDS xeem. Txoj kev tshawb no tsim kom muaj kev sib xyaw ua ke los tiv thaiv kev laus rau cov ntaub ntawv asphalt kom txo tau cov thermal-oxidative aging ntawm asphalt ntawm qib tivthaiv, kev txhim kho cov durability ntawm asphalt pavement.
2. Cov ntaub ntawv thiab cov txheej txheem
2.1. Raz0 Cov ntaub ntawv
Hauv txoj kev tshawb no, tus neeg siv asphalt nrog qib 60/80 nkag mus tau yuav los ntawm California Texas Oil Company, Tebchaws Asmeskas. SARA feem ntau raug cais tawm ntawm asphalt binder raws li ASTMD4124-09. Cov ntsiab lus ntawm saturates, aromatics, resins, thiab asphaltenes yog 18.4 feem pua, 40.7 feem pua, 30.9 feem pua, thiab 10 feem pua ntawm qhov hnyav, feem.
tau raug xaiv los ua tus adsorbent los thauj MH thiab CaCO3 rau kev npaj cov tshuaj tiv thaiv kev laus ntawm saturates thiab aromatics, feem. MH thiab CaCO: tau raug hloov kho los ntawm tus neeg sawv cev silane coupling. Kev nthuav dav ntawm EGis 210mL / g. Qhov luaj li cas ntawm MHand CaCO, yog 30-50 nm thiab 40-80 nm, feem. Lub purity ntawm MH thiab CaCO; yog ob qho tib si ntau dua 98 feem pua. Cov yam ntxwv ntawm cov asphalt zoo huv si thiab cov neeg ua haujlwm tiv thaiv kev laus hloov kho asphalt tau sau tseg hauv Table 1.
2.2. Kev npaj ua qauv
2.2.1. Kev txiav txim siab npaum li cas ntawm Anti-Aging Agents
Nws paub tias EG thiab nano MH muaj cov txiaj ntsig zoo thaum lawv cov ntsiab lus piv yog 5: 6 los ntawm qhov hnyav [32]. Thaum cov ntsiab lus piv ntawm EG thiab nano CaCO, yog 5:12 los ntawm qhov hnyav, qhov poob ntawm asphalt thaum cua sov yog qhov tsawg tshaj plaws [33]. Yog li, qhov sib xyaw ntawm EG rau MH tau txiav txim siab li 5: 6 ntxiv rau hauv saturates, thiab qhov sib xyaw ntawm EG rau CaCO yog 5: 12 ntxiv rau hauv aromatics. Raws li cov ntsiab lus ntawm saturates thiab aromatics hauv asphalt, qhov sib xyaw ua ke ntawm EG, MH, thiab CaCO, nyob rau hauv kev npaj cov tshuaj tiv thaiv kev laus yog 2: 1: 3. Yog li ntawd, cov tshuaj ntxiv ntawm EG/MHin saturates, EG/CaCO3 hauv aromatics, thiab EG/MH/CaCO; hauv asphalt yog 10 wt. feem pua raws li kev tshawb fawb yav dhau los [23]. Raws li cov hmoov additive, qhov cuam tshuam ntawm cov tshuaj tiv thaiv kev laus ntawm kev ua yeeb yam ntawm asphalt tau raug txiav txim siab. Cov khoom tseem ceeb ntawm asphalt muaj 10 wt. feem pua cov neeg sawv cev tiv thaiv kev laus tau raug sim raws li tau muab hauv Table 1, qhia tias qhov kev ua tau zoo ntawm cov tshuaj tiv thaiv kev laus tau hloov kho asphalt raws li cov qauv kev cai.
2.2.2. Kev npaj cov qauv uas muaj Composite Anti-Aging Agents
Ua ntej, 50mg EG tau qhuav hauv qhov cub nqus tsev ntawm 60 degree rau 5 h. Cov EG qhuav tau muab tso rau hauv qhov cub sov ntawm 800 degree thiab nthuav dav rau 60 s kom tau txais cov EG nthuav dav nrog qhov ntim ntawm 210 mL / g. Qhov thib ob, MH thiab CaCO3 nanoparticles tau doped ntawm EG los ntawm hydrothermal synthesis. Kaum mg expanded EG yog tov nrog 12 mg MH thiab 24 mg CaCO3 nyob rau hauv cov dej deionized, feem.cov txiaj ntsig cynomoriumTom qab ntawd, ob qhov kev daws teeb meem sib xyaw tau hloov mus rau ob lub Teflon-lined autoclaves. Cov autoclaves tau khaws cia ntawm 120 degree rau 3 h, thiab tom qab ntawd txias txias rau chav sov. Cov qauv npaj tau raug ntxuav peb zaug siv centrifugation nrog dej deionized thiab ethanol kiag li, nrog rau ziab hauv qhov cub ntawm 60 degree kom tau EG/MH thiab EG/CaCO3 [34,35]. Peb caug mg nthuav dav EG tau tov nrog 15 mg MH thiab 45 mg CaCO, hauv dej deionized. Tom qab ntawd, EG/MH/CaCO3 tau npaj los ntawm kev rov ua cov kauj ruam saum toj no.
Thib peb, saturates, aromatics, asphalt, EG / MH, EG / CaCO3, thiab EG / MH / CaCO3 tau muab tso rau hauv qhov cub kom qhuav nrog lub tshuab nqus tsev ntawm 93 ± 1 kPa ntawm 105 degree rau 1 h. Tom qab ntawd, EG / MH, EG / CaCO3, thiab EG / MH / CaCO3 tau maj mam ntxiv hauv saturates aromatics thiab asphalt ntawm cov ntsiab lus ntawm 10 wt. feem pua , raws li tau zoo raws li stirred siv lub shear dispersion tshuab (FM300 hom, FLUKO Equipment Co., Ltd, Shanghai, Tuam Tshoj) ntawm 1000 rpm rau 5 min, ua raws li los ntawm ib tug siab stirring ceev ntawm 4000 rpm rau 20 min. Thaum kawg, tes nplawm tau siv los tiv thaiv kev sib cais thiab tshem tawm cov npuas npuas kom txog thaum cov qauv npaj tau txias rau chav tsev kub.
2.3.Txoj kev
2.3.1. Isothermal TG/DSC-FTIR Test
Raws li peb txoj kev kawm yav dhau los [31], TG / DSC xeem system (STA 409, Netzsch, Lub teb chaws Yelemees) ua ke nrog FTIR spectrometer (Nicolet IS10, Thermo scientific, Grand Island, NY, USA) tau siv los ntsuas qhov cuam tshuam ntawm kev tiv thaiv. -aging cov neeg ua haujlwm ntawm thermal-oxidative aging ntawm saturates, aromatics, thiab asphalt, feem. Kwv yees li ntawm 10 mg ntawm cov qauv tau muab tso rau hauv alumina crucibles ntawm TG / DSC xeem system. Cov cua kub kub tau nce mus rau 163 degree los ntawm chav tsev kub ntawm qhov cua sov ntawm 40 degree / min thiab tuav ntawm 163 degree rau 4 h raws li Suav Standard Test Methods ntawm Bitumen thiab Bituminous Mixture rau Highway Engineering [36]. Tom qab ntawd, 21 feem pua ntawm cov pa oxygen thiab 79 feem pua nitrogen tau nkag ntawm tus nqi ntws ntawm 60 mL / min. Yog li, kev ntsuam xyuas thermal-oxidative aging ntawm saturates, aromatics, thiab asphalt kuaj tau ua los tham txog cov kev hloov pauv hauv huab hwm coj poob, cua sov enthalpy, thiab volatile constituents thaum lub sij hawm isothermal cua sov ua ntej thiab tom qab ntxiv anti-aging agents, raws li. Cov txheej txheem linear hauv paus tau siv los xam thaj tsam ntawm endothermic lossis exothermic peaks ntawm DSC nkhaus. Qhov chaw nruab nrab ntawm lub hauv paus thiab qhov kawg ntawm qhov kawg lossis qhov kawg ntawm qhov kawg ntawm DSC nkhaus tau suav kom tau txais enthalpy.
Nyob rau tib lub sijhawm, cov volatiles tso tawm tau raug xa mus rau hauv kev sib xyaw ua ke FTIR analyzer ((Nicolet IS10, Thermo scientific, GrandIsland, NY, USA) los ntawm cov roj lim dej ntawm tus nqi ntws ntawm 120 mL / min. Cov txiaj ntsig FTIR tau sau tseg tsis tu ncua Ua ntej qhov kev xeem isothermal TG/DSC-FTIR ntawm txhua tus qauv, qhov ntsuas kub thiab qhov sib npaug tau ua tiav, thiab kev sim ua ntej rau kev kuaj rov ua dua nyob rau hauv tib qhov kev sim tau ua peb zaug. Thaum cov txiaj ntsig tau pom tias TG thiab DSC curves superposed zoo kawg nkaus thiab qhov ua yuam kev tau txais, qhov kev sim ntawm txhua tus qauv tau ua tiav. Yog li ntawd, plaub cov qauv tau npaj los qhia txog qhov cuam tshuam ntawm cov tshuaj tiv thaiv kev laus ntawm thermal-oxidative aging zog ntawm saturates, aromatics, thiab asphalt, feem.
2.3.2.ESEM-EDS Test
Cov kev hloov pauv hauv micromorphology thiab cov ntsiab lus tseem ceeb ntawm cov qauv asphalt ua ntej thiab tom qab simulated isothermal-oxidative aging saum toj no yog tus cwj pwm los ntawm ESEM (Quanta 200 hom, FEI, Grand Island, NY, USA) nruab nrog EDS. Ua ntej, asphalt nrog ib qho piv txwv loj ntawm 1 cm × 1 cm × 1 cm tau npaj thiab muab tso rau hauv cov qauv huv si siv cov nplaum nplaum. Tom qab ntawd, cov hmoov kub tau muab txau rau ntawm cov qauv asphalt thiab qhov chaw soj ntsuam tau nqus kom txog thaum lub siab mus txog -3.06 × 10-3 Pa.suab puam hyacinthCov qauv morphologies tau pom tam sim ntawd siv ESEM, thiab cov tshuaj muaj pes tsawg leeg tau kuaj pom siv EDS. Cov ntsiab lus ntawm cov tshuaj lom neeg yog qhov nruab nrab ntawm peb qhov ntsuas qhov ntsuas ntawm txhua tus qauv.
3. Cov txiaj ntsig thiab kev sib tham
3.1.Thermal Stability Effects Anti-Aging Agents ntawm Saturates Thiab Aromatics
Txhawm rau tham txog cov teebmeem ntawm kev npaj cov tshuaj tiv thaiv kev laus ntawm EG / MH thiab EG / CaCO3 ntawm thermal stability ntawm saturates thiab aromatics, isothermal TG / DSC-FTIR tests tau ua los simulate thermal-oxidative laus ntawm 163 degree C rau 4 h. .
3.1.1. Thermal Stability Effect ntawm EG/MH ntawm Saturates
TG thiab DSC nkhaus ntawm saturates thiab saturates / EG / MH thaum lub sij hawm isothermal-oxidative laus yog qhia nyob rau hauv daim duab 1.
Los ntawm TG nkhaus nyob rau hauv daim duab 1, nws pom tau hais tias qhov loj ntawm saturates yog txo qis raws li lub thermal-oxidative aging ncua ntev ua ntej thiab tom qab ntxiv EG / MH. Qhov txo qis ntawm saturates / EG / MH tsawg dua li cov saturates. Qhov no qhia tau hais tias cov tshuaj tiv thaiv decomposition thiab volatilization ntawm lub teeb Cheebtsam nyob rau hauv saturates yog txo tom qab ntxiv EG / MH thaum lub sij hawm thermal-oxidative laus ntawm saturates. Qhov no yog vim EG/MHplays lub filling thiab stabilizing lub luag hauj lwm nyob rau hauv saturates, thiab cov ntxeem tau EG muaj ib tug muaj zog adsorption kev ua tau zoo kom ib co luv luv-chain hydrocarbon molecules yog adsorbed los ntawm EG [12].
Txij li thaum cov cua kub kub tsis tu ncua, qhov kev hloov pauv ntawm cov cua sov yog feem ntau yog vim qhov kub sib txawv ntawm cov saturates thiab cov qauv siv cov khoom siv. Lub DSC nkhaus ntawm saturates thiab saturates / EG / MH hloov tsis tu ncua ntawm 163 degree rau 4 h, thiab qhov hloov pauv ntawm saturates loj dua li ntawm saturates / EG / MH. Qhov no qhia tias cov khoom sib txawv hauv saturates koom nrog cov tshuaj tiv thaiv ntawm cov cua sov sib txawv thaum lub sij hawm isothermal-oxidative aging ntawm saturates. Ntxiv mus, kuj khaus thiab complex endothermic thiab exothermic tshua tshwm sim. Qhov no yog vim saturates yog lub teeb nyob rau hauv asphalt, thiab lub ntsiab molecular chains thiab lateral chains yog yooj yim fractured nyob rau hauv high kub kom tso tawm los yog adsorb kub thaum lub sij hawm isothermal-oxidative laus ntawm saturates.
Tsis tas li ntawd, qhov kub ntawm qhov ntsuas kub ntawm saturates thiab saturates / EG / MH qhia qhov nce ntxiv ntawm tag nrho, tab sis cov nqi hluav taws xob ntawm cov saturates siab dua cov saturates / EG / MH. Qhov no qhia tau hais tias saturates tau txais cov tshuaj tiv thaiv endothermic tag nrho thaum lub sij hawm isothermal-oxidative laus ntawm 163 degree rau 4 h. Nws tau pom tias DSC nkhaus qhia tias cov tshuaj tiv thaiv tshav kub yog pom tseeb txo qis tom qab ntxiv EG / Mein saturates. Yog vim li cas yog tias EG adsorbs me me hydrocarbon molecules thiab insulates oxygen thiab cua sov, cuam tshuam ntxiv thermal oxidation. MH yog loaded ntawm ntxeem tau EG los kho me me molecules, filling thiab stabilizing saturates [11,23]. Cov teebmeem synergetic ntawm EG thiab MH nce lub thermal stability ntawm saturates, thiab cov tshuaj tiv thaiv tsis muaj zog, ua rau txo qis hauv cov tshuaj tiv thaiv thaum lub sij hawm isothermal-oxidative laus.
3.1.2. Thermal Stability Effect of EG/CaCO3 on Aromatics
Isothermal TG / DSC kev ntsuam xyuas yog ua los ntawm aromatics ua ntej thiab tom qab ntxiv EG / CaCO3 ntawm 163 degree rau 4 teev. TG thiab DSC curves aromatics thiab aromatics / EG / CaCO, thaum lub sij hawm isothermal-oxidative laus, muaj nyob rau hauv daim duab 2.
Los ntawm TG nkhaus hauv daim duab 2, nws tau muab sau tseg tias aromatics tsis muaj cov tshuaj tiv thaiv kev laus ntawm EG / CaCO: qhia me ntsis kev nce hauv huab hwm coj, thaum qhov loj ntawm aromatics tom qab ntxiv EG / CaCO3 hauv aromatics yog me ntsis txo thaum lub isothermal. - oxidative kev laus. Qhov no qhia tau hais tias cov tshuaj tiv thaiv polymerization hauv aromatics ntau dua li cov tshuaj tiv thaiv decomposition ua ntej ntxiv EG thiab CaCO, nanoparticles, tsim qee cov khoom macromolecular. Qhov no yog vim hais tias aromatics yog hloov resins vim oxidative polymerization thaum lub sij hawm isothermal-oxidative laus, thiab lateral chains ntawm aromatic rings yog ib qho yooj yim rau oxidized thiab polymerized los ua aromatic cycloalkyl [37]. Txawm li cas los xij, cov tshuaj tiv thaiv polymerization hauv cov tshuaj tsw qab yog tsawg dua cov tshuaj tiv thaiv decomposition tom qab ntxiv EG / CaCO3, ua rau txo qis ntawm cov tshuaj tsw qab thaum lub sij hawm isothermal-oxidative laus. Qhov no feem ntau yog vim qhov tseeb tias qee lub teeb pom kev zoo yog adsorbed thiab kho los ntawm EG los tiv thaiv cov tiam ntawm macromolecules los ntawm kev ntxiv oxidative polymerization cov tshuaj tiv thaiv nrog oxygen [38]. Txawm li cas los xij, ib qho me me ntawm cov khoom me me molecular kuj tau dim thaum lub sij hawm thermal decomposition cov tshuaj tsw qab ntawm aromatics. Thaum cov huab hwm coj ntawm emission volatile loj dua li ntawm cov macromolecules tsim los ntawm cov tshuaj tiv thaiv polymerization, tag nrho cov aromatics yog me ntsis txo. Lub caij no, cov hydrophilic CaCO nanoparticles loaded ntawm ntug thiab sab hauv phab ntsa ntawm EG uniformly disperse nyob rau hauv aromatics los tsim ib tug cross-linking qauv, kev txhim kho lub thermal stability ntawm aromatics thiab ua rau nws loj poob mus rau qeeb qeeb.
Raws li pom nyob rau hauv daim duab 2, DSC curves qhia tau hais tias qhov kev mob siab heev thiab nyuaj endothermic cov tshuaj tiv thaiv tshwm sim nyob rau hauv isothermal-oxidative aging txheej txheem ntawm aromatics, tawm tswv yim hais tias sib txawv Cheebtsam nyob rau hauv aromatics koom nyob rau hauv cov tshuaj tiv thaiv ntawm txawv cua sov theem thaum lub isothermal-oxidative laus. Tom qab ntxiv EG / CaCO, qhov hloov pauv ntawm cov cua sov ntws ntawm cov tshuaj tsw qab yuav luag sib npaug rau abscissa. Qhov no qhia tias qhov thermal stability ntawm aromatics yog txhim kho, uas yog vim muaj kev sib koom ua ke ntawm EG thiab CaCO. Kev nqus ntawm EG cuam tshuam cov saw tshuaj tiv thaiv, inhibiting thermal-oxidative aging txheej txheem ntawm aromatics. Cov teebmeem saum npoo ntawm CaCO: nanoparticles ntxiv stabilize lub cev lub cev ntawm aromatics, txhim kho thermal stability ntawm aromatics.
Kab lus no tau muab rho tawm los ntawm Cov Khoom Siv 2020, 13, 4005; doi: 10.3390/ma13184005 www.mdpi.com/journal/materials
