Hauv cov mortar qhuav, cellulose ether yog ib qho khoom siv tseem ceeb uas tuaj yeem txhim kho kev ua tau zoo ntawm cov mortar ntub thiab cuam tshuam rau kev ua haujlwm ntawm mortar. Methyl cellulose ether ua lub luag haujlwm ntawm kev khaws dej, thickening, thiab kev txhim kho kev ua haujlwm ntawm kev tsim kho. Kev ua tau zoo ntawm kev khaws dej ua kom ntseeg tau tias cov mortar yuav tsis ua rau sanding, hmoov thiab txo lub zog vim tsis muaj dej txaus thiab tsis tiav cement hydration; thickening effect Lub zog ntawm cov mortar ntub tau nce ntau heev, thiab ntxiv methyl cellulose ether tuaj yeem txhim kho qhov viscosity ntub ntawm cov mortar ntub, thiab muaj kev nplaum zoo rau ntau yam substrates, yog li txhim kho kev ua tau zoo ntawm cov mortar ntub ntawm phab ntsa thiab txo cov khib nyiab; ntxiv rau, txawv Lub luag haujlwm ntawm cellulose hauv cov khoom kuj txawv, piv txwv li: cellulose hauv cov nplais nplaum tuaj yeem ua rau lub sijhawm qhib thiab kho lub sijhawm; cellulose hauv cov mortar txau tshuab tuaj yeem txhim kho lub zog ntawm cov mortar ntub; hauv kev ntsuas tus kheej, cellulose ua lub luag haujlwm hauv kev tiv thaiv kev sib haum xeeb, kev sib cais thiab kev faib ua pawg.
Kev tsim cov cellulose ether feem ntau yog ua los ntawm cov fibers ntuj los ntawm kev yaj alkali, kev sib xyaw ua ke (etherification), ntxuav, ziab, sib tsoo thiab lwm yam txheej txheem. Cov khoom siv tseem ceeb ntawm cov fibers ntuj tuaj yeem muab faib ua: paj rwb fiber, cedar fiber, beech fiber, thiab lwm yam. Lawv qib polymerization txawv, uas yuav cuam tshuam rau qhov viscosity kawg ntawm lawv cov khoom. Tam sim no, cov chaw tsim khoom cellulose loj siv paj rwb fiber (ib qho khoom lag luam ntawm nitrocellulose) ua cov khoom siv tseem ceeb. Cellulose ethers tuaj yeem faib ua ionic thiab non-ionic. Hom ionic feem ntau suav nrog carboxymethyl cellulose ntsev, thiab hom non-ionic feem ntau suav nrog methyl cellulose, methyl hydroxyethyl (propyl) cellulose, thiab hydroxyethyl cellulose. Su thiab lwm yam. Hauv cov hmoov qhuav mortar, vim tias ionic cellulose (carboxymethyl cellulose ntsev) tsis ruaj khov nyob rau hauv qhov muaj calcium ions, nws tsis tshua siv hauv cov khoom hmoov qhuav xws li cement slaked lime ua cov ntaub ntawv cementitious.
Qhov kev khaws dej ntawm cellulose kuj muaj feem cuam tshuam nrog qhov kub thiab txias siv. Qhov kev khaws dej ntawm methyl cellulose ether txo qis nrog rau qhov nce ntawm qhov kub thiab txias. Piv txwv li, thaum lub caij ntuj sov, thaum muaj hnub ci, phab ntsa sab nraud putty yog plastered, uas feem ntau ua kom cov cement thiab mortar kho sai dua. Qhov tawv thiab qhov txo qis ntawm qhov ceev khaws dej ua rau muaj kev xav tias ob qho tib si kev ua tau zoo ntawm kev tsim kho thiab kev ua haujlwm tiv thaiv kev tawg raug cuam tshuam. Hauv qhov no, nws yog qhov tseem ceeb heev kom txo qhov cuam tshuam ntawm cov yam ntxwv kub. Qee zaum nws tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev siv. Qee qhov kev kho mob tau ua rau ntawm cellulose, xws li kev nce qib ntawm etherification, thiab lwm yam, yog li ntawd qhov cuam tshuam ntawm kev khaws dej tseem tuaj yeem tswj tau qhov cuam tshuam zoo dua ntawm qhov kub siab dua.
Kev khaws dej ntawm cellulose: Cov yam tseem ceeb uas cuam tshuam rau kev khaws dej ntawm cov mortar suav nrog qhov ntau ntawm cellulose ntxiv, qhov viscosity ntawm cellulose, qhov zoo ntawm cellulose, thiab qhov kub ntawm qhov chaw ua haujlwm.
Viscosity ntawm cellulose: Feem ntau hais lus, qhov siab dua qhov viscosity, qhov zoo dua qhov dej tuav cov nyhuv, tab sis qhov siab dua qhov viscosity, qhov siab dua qhov molecular hnyav ntawm cellulose, thiab qhov sib xws txo qis hauv nws cov solubility, uas muaj qhov tsis zoo rau kev tsim kho kev ua tau zoo thiab lub zog ntawm mortar. Qhov siab dua qhov viscosity, qhov ntau dua qhov thickening nyhuv ntawm mortar, tab sis nws tsis yog proportional ncaj qha. Qhov siab dua qhov viscosity, qhov ntau dua qhov ntub mortar yuav yog. Thaum lub sijhawm tsim kho, nws yuav lo rau ntawm scraper thiab muaj kev nplaum siab rau lub substrate, tab sis nws yuav tsis pab ntau los ua kom lub zog ntawm cov ntub mortar nws tus kheej nce, thiab qhov kev ua tau zoo tiv thaiv kev sag yuav tsis pom tseeb thaum lub sijhawm tsim kho.
Qhov zoo ntawm cellulose: Qhov zoo cuam tshuam rau qhov solubility ntawm cellulose ether. Cov cellulose ntxhib feem ntau yog granular thiab yooj yim dispersed hauv dej yam tsis muaj agglomeration, tab sis qhov kev yaj qeeb heev. Nws tsis haum rau siv hauv cov hmoov qhuav mortar. Cov khoom tsim hauv tsev Qee cov cellulose yog flocculent, nws tsis yooj yim rau disperse thiab yaj hauv dej, thiab nws yooj yim rau agglomerate. Tsuas yog cov hmoov zoo txaus tuaj yeem zam methyl cellulose ether agglomeration thaum ntxiv dej thiab do. Tab sis cov cellulose ether tuab dua tsis yog tsuas yog pov tseg tab sis kuj txo qhov muaj zog hauv zos ntawm cov mortar. Thaum cov hmoov qhuav mortar zoo li no tau tsim hauv thaj chaw loj, qhov ceev kho ntawm cov mortar hauv zos tau pom tseeb txo qis, thiab cov kab nrib pleb vim yog lub sijhawm kho sib txawv tshwm sim. Vim yog lub sijhawm sib tov luv luv, cov mortar nrog kev tsim kho tshuab xav tau qhov zoo dua.
Lub sijhawm tshaj tawm: Lub Ob Hlis-13-2023