Cellulose ethers yog ib hom organic polymer tebchaw chemically hloov los ntawm ntuj cellulose. Lawv feem ntau siv hauv cov khoom siv hauv tsev, tshwj xeeb tshaj yog cov khoom siv cement. Kev cuam tshuam ntawm cellulose ether ntawm cov txheej txheem cement hydration feem ntau yog tshwm sim hauv cov hauv qab no: cov khoom tawg ntawm cov cement, dej tuav, cov nyhuv thickening, thiab kev cuam tshuam ntawm morphology thiab lub zog loj hlob ntawm cov khoom cement hydration.
1. Taw qhia txog cement hydration
Cov txheej txheem hydration ntawm cov cement yog ib qho kev sib txuam ntawm lub cev thiab tshuaj lom neeg ntawm cov cement thiab dej. Cov tshuaj tiv thaiv no ua rau cov cement muab tshuaj maj mam ua kom muaj cov qauv zoo, thaum kawg tsim cov khoom siv dej xws li calcium silicate hydrate (CSH) thiab calcium hydroxide (CH). Thaum lub sij hawm tus txheej txheem no, hydration cov tshuaj tiv thaiv ntawm cov cement, fluidity thiab dej tuav ntawm slurry, thiab tsim cov khoom hydration ncaj qha cuam tshuam rau lub zog thiab durability ntawm cov pob zeb zaum kawg.
2. Lub tshuab ua haujlwm ntawm cellulose ethers
Cellulose ether plays lub luag haujlwm tseem ceeb ntawm lub cev thiab tshuaj lom neeg kev tswj hwm hauv cov txheej txheem cement hydration. Cellulose ether feem ntau cuam tshuam rau cov txheej txheem dej ntawm cov cement hauv ob txoj kev: ib qho yog los ntawm kev cuam tshuam rau kev faib thiab evaporation ntawm cov dej hauv cov cement slurry; Lwm qhov yog los ntawm kev cuam tshuam cov dispersion thiab coagulation ntawm cov cement hais.
Kev tswj cov dej noo thiab khaws cia dej
Cellulose ethers tuaj yeem txhim kho cov dej khaws cia ntawm cov khoom siv cement. Vim nws muaj zog hydrophilicity, cellulose ether tuaj yeem tsim cov tshuaj colloidal ruaj khov hauv dej, uas tuaj yeem nqus tau thiab khaws cov dej noo. Lub peev xwm tuav dej no yog qhov tseem ceeb hauv kev txo cov kab nrib pleb uas tshwm sim los ntawm kev poob dej sai hauv cov pob zeb thaum lub sij hawm ntxov hydration. Tshwj xeeb tshaj yog nyob rau hauv ib puag ncig qhuav los yog kub-kub kev tsim kho, cellulose ether tuaj yeem tiv thaiv dej los ntawm evaporating sai heev thiab xyuas kom meej tias cov dej hauv cov cement slurry txaus los txhawb cov dej tsis zoo.
Rheology thiab Thickening
Cellulose ethers kuj tuaj yeem txhim kho rheology ntawm cement slurries. Tom qab ntxiv cellulose ether, qhov sib xws ntawm cov cement slurry yuav nce ntau. Qhov tshwm sim no feem ntau yog los ntawm cov qauv saw ntev uas tsim los ntawm cellulose ether molecules hauv dej. Qhov ntev-chain molecule no tuaj yeem txwv kev txav ntawm cov cement hais, yog li ua kom cov viscosity thiab sib xws ntawm slurry. Cov cuab yeej no tseem ceeb tshwj xeeb hauv kev siv xws li plastering thiab pobzeb adhesives, vim nws tiv thaiv cov cement mortar los ntawm ntws sai heev thaum muab kev tsim kho zoo dua.
Ncua dej thiab kho lub sijhawm teeb tsa
Cellulose ether tuaj yeem ncua sijhawm cov tshuaj tiv thaiv dej ntawm cov cement thiab nce qhov chaw pib thiab lub sijhawm kawg ntawm cov cement slurry. Qhov no tshwm sim vim hais tias cov molecules ntawm cellulose ether yog adsorbed nyob rau saum npoo ntawm cov cement hais, ua ib qho barrier uas tiv thaiv kev sib cuag ncaj qha ntawm cov dej thiab cov cement hais, yog li qeeb cov tshuaj tiv thaiv hydration. Los ntawm ncua sij hawm teem sijhawm, cellulose ethers tuaj yeem txhim kho kev tsim kho, muab sijhawm rau cov neeg ua haujlwm tsim kho kom kho thiab kho.
3. Qhov cuam tshuam rau daim ntawv ntawm cov khoom siv cement hydration
Lub xub ntiag ntawm cellulose ethers kuj cuam tshuam rau microstructure ntawm cement hydration khoom. Cov kev tshawb fawb tau pom tias morphology ntawm calcium silicate hydrate (CSH) gel yuav hloov tom qab ntxiv cellulose ether. Cellulose ether molecules tuaj yeem cuam tshuam cov qauv siv lead ua ntawm CSH, ua rau nws xoob. Cov qauv xoob no tuaj yeem txo qis lub zog thaum ntxov rau qee qhov, tab sis nws kuj pab txhim kho lub zog ntawm cov khoom.
Cellulose ethers kuj tuaj yeem txo qhov tsim ntawm ettringite thaum lub sij hawm hydration txheej txheem. Txij li thaum cellulose ether retards tus nqi ntawm cov tshuaj tiv thaiv hydration, qhov tsim tus nqi ntawm ettringite nyob rau hauv cov cement yog txo, yog li txo cov kev ntxhov siab sab hauv los ntawm ntim expansion thaum lub sij hawm kho.
4. cuam tshuam rau kev txhim kho lub zog
Cellulose ethers kuj tseem muaj feem cuam tshuam rau kev txhim kho lub zog ntawm cov khoom siv cement. Vim tias cellulose ethers retard lub hydration tus nqi ntawm cov cement, lub zog thaum ntxov ntawm cov cement pastes feem ntau qeeb dua. Txawm li cas los xij, raws li cov tshuaj tiv thaiv hydration txuas ntxiv mus, kev tswj cov nyhuv ntawm cellulose ether dej tuav thiab hydration khoom morphology tuaj yeem maj mam tshwm sim, uas yuav pab txhim kho lub zog nyob rau theem tom ntej.
Nws yuav tsum raug sau tseg tias qhov ntxiv thiab hom cellulose ether muaj ob qho kev cuam tshuam rau lub zog. Tus nqi tsim nyog ntawm cellulose ether tuaj yeem txhim kho kev tsim kho thiab ua kom muaj zog tom qab, tab sis kev siv ntau dhau tuaj yeem ua rau txo qis ntawm lub zog thaum ntxov ntawm cov ntaub ntawv cement-based thiab cuam tshuam rau cov khoom siv kho tshuab kawg. Yog li ntawd, nyob rau hauv kev siv tswv yim, hom thiab ntau npaum li cas ntawm cellulose ether yuav tsum tau optimized thiab tsim raws li cov kev cai engineering.
Cellulose ether cuam tshuam rau cov txheej txheem hydration thiab cov khoom siv ntawm cov cement los ntawm kev txhim kho cov dej tuav ntawm cov khoom siv cement, kho cov hydration tus nqi, thiab cuam tshuam rau cov khoom hydration. Txawm hais tias cellulose ethers tuaj yeem ua rau poob ntawm lub zog thaum ntxov, lawv tuaj yeem txhim kho cov kav ntev thiab tawv ntawm pob zeb rau lub sijhawm ntev. Qhov sib ntxiv ntawm cellulose ether kuj tseem tuaj yeem txhim kho kev tsim kho kev ua tau zoo, tshwj xeeb tshaj yog nyob rau hauv daim ntawv thov scenarios uas yuav tsum tau ua haujlwm ntev thiab kev tuav dej siab. Nws muaj irreplaceable zoo. Hauv kev siv engineering tiag tiag, kev xaiv tsim nyog ntawm hom thiab ntau npaum li cas ntawm cellulose ether tuaj yeem sib npaug ntawm lub zog, kev tsim kho thiab kev ua haujlwm ntev ntawm cov khoom.
Post lub sij hawm: Sep-27-2024