Hauv cov khoom sib xyaw ua ke, qhov sib ntxiv ntawm hydroxypropyl methyl cellulose HPMC yog qhov tsawg heev, tab sis nws tuaj yeem txhim kho kev ua haujlwm ntawm cov mortar ntub dej, uas yog ib qho tseem ceeb ntxiv uas cuam tshuam rau kev tsim kho ntawm mortar. Cellulose ethers nrog cov viscosity sib txawv thiab cov nyiaj ntxiv muaj txiaj ntsig zoo rau kev txhim kho kev ua haujlwm ntawm cov tshuaj khib nyiab qhuav. Tam sim no, ntau cov masonry thiab plastering mortars muaj cov dej tsis zoo, thiab cov dej slurry sib cais tshwm sim tom qab ob peb feeb ntawm kev sawv tseem. Kev tuav dej yog qhov tseem ceeb ntawm kev ua haujlwm ntawm methyl cellulose ether, thiab nws kuj yog ib qho kev ua tau zoo uas ntau lub tuam txhab siv tshuaj khib nyiab hauv tsev, tshwj xeeb tshaj yog cov neeg nyob hauv thaj chaw uas muaj qhov kub siab dua nyob rau sab qab teb, ua tib zoo mloog. Cov yam ntxwv cuam tshuam rau cov dej tuav cov nyhuv ntawm cov tshuaj khib nyiab qhuav suav nrog cov nqi ntawm HPMC ntxiv, viscosity ntawm HPMC, qhov zoo ntawm cov khoom thiab qhov kub ntawm qhov chaw uas nws siv.
1. Lub tswv yim: Cellulose ether yog hluavtaws siab molecular polymer ua los ntawm ntuj cellulose los ntawm kev hloov tshuaj lom neeg. Cellulose ether yog derivative ntawm natural cellulose. Kev tsim cov cellulose ether yog txawv los ntawm hluavtaws polymers. Nws cov khoom siv yooj yim tshaj plaws yog cellulose, lub ntuj polymer compound. Vim yog cov qauv tshwj xeeb ntawm ntuj cellulose, cellulose nws tus kheej tsis muaj peev xwm ua rau cov tshuaj etherifying. Tab sis tom qab tus neeg sawv cev o tau kho, lub zog hydrogen bonds ntawm cov saw hlau molecular thiab hauv cov saw hlau raug rhuav tshem, thiab cov active tso tawm ntawm pawg hydroxyl hloov mus rau reactive alkali cellulose. Tom qab tus neeg sawv cev etherification reacts, pawg -OH hloov mus rau pawg -OR. Tau txais cellulose ether. Qhov xwm ntawm cellulose ether nyob ntawm hom, kom muaj nuj nqis thiab kev faib tawm ntawm cov khoom hloov pauv. Kev faib tawm ntawm cellulose ethers kuj yog nyob ntawm hom kev hloov pauv, qib ntawm etherification, solubility thiab lwm yam kev siv. Raws li hom kev hloov pauv ntawm cov saw hlau molecular, nws tuaj yeem muab faib ua monoether thiab sib xyaw ether. HPMC peb feem ntau siv yog sib xyaw ether. Hydroxypropyl methyl cellulose ether HPMC yog cov khoom lag luam uas ib feem ntawm cov pab pawg hydroxyl ntawm chav tsev yog hloov los ntawm methoxy pawg thiab lwm qhov yog hloov los ntawm pawg hydroxypropyl. HPMC feem ntau yog siv rau hauv cov khoom siv hauv tsev, latex coatings, tshuaj, chemistry txhua hnub, thiab lwm yam. Siv ua cov thickener, water-retaining agent, stabilizer, dispersant, thiab film-forming agent.
2. Dej tuav ntawm cellulose ether: nyob rau hauv kev tsim cov ntaub ntawv hauv tsev, tshwj xeeb tshaj yog cov mortar qhuav, cellulose ether plays lub luag hauj lwm irreplaceable, tshwj xeeb tshaj yog nyob rau hauv zus tau tej cov tshwj xeeb mortar (hloov mortar), nws yog indispensable. tiv thaiv. Lub luag haujlwm tseem ceeb ntawm cov dej-soluble cellulose ether hauv mortar yog feem ntau nyob rau hauv peb yam. Ib qho yog cov dej tuav tau zoo heev, lwm qhov yog qhov cuam tshuam ntawm qhov sib xws thiab thixotropy ntawm mortar, thiab qhov thib peb yog kev cuam tshuam nrog cov cement. Cov dej tuav cov nyhuv ntawm cellulose ether nyob ntawm qhov nqus dej ntawm lub hauv paus txheej, muaj pes tsawg leeg ntawm mortar, txheej thickness ntawm cov mortar, cov dej xav tau ntawm cov mortar, thiab lub sij hawm teem sij hawm ntawm cov khoom coagulating. Cov dej tuav ntawm cellulose ether nws tus kheej los ntawm solubility thiab lub cev qhuav dej ntawm cellulose ether nws tus kheej.
Lub thickening thiab thixotropy ntawm cellulose ether: Lub luag hauj lwm thib ob ntawm cellulose ether-thickening nyob ntawm: qib ntawm polymerization ntawm cellulose ether, kua concentration, kub thiab lwm yam mob. Cov khoom gelation ntawm cov tshuaj yog cov khoom tshwj xeeb ntawm alkyl cellulose thiab nws cov derivatives hloov. Cov yam ntxwv gelation muaj feem xyuam rau qib ntawm kev hloov pauv, kev daws teeb meem thiab cov additives.
Lub peev xwm tuav dej zoo ua rau cov cement hydration ntau dua, tuaj yeem txhim kho qhov ntub dej ntawm cov khib nyiab ntub dej, ua kom lub zog sib txuas ntawm cov mortar, thiab lub sijhawm tuaj yeem hloov kho. Qhov sib ntxiv ntawm cellulose ether rau cov neeg kho tshuab txau mortar tuaj yeem txhim kho cov tshuaj tsuag lossis cov twj tso kua mis ntawm cov tshuaj khib nyiab, nrog rau lub zog ntawm cov qauv. Yog li ntawd, cellulose ether tau dav siv los ua ib qho tseem ceeb additive nyob rau hauv npaj-mixed mortar.
Post lub sij hawm: Dec-16-2021