Cov yam ntxwv ntawm cov khoom siv hauv tsev qib cellulose ether

Cov khoom siv ntxiv ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua haujlwm ntawm lub tsev qhuav-sib xyaw mortar, suav txog ntau dua 40% ntawm cov khoom siv hauv cov khoom siv qhuav qhuav. Ib qho tseem ceeb ntawm cov khoom siv hauv kev lag luam hauv tsev yog muab los ntawm cov tuam txhab txawv teb chaws, thiab cov khoom siv ntawm cov khoom siv kuj yog muab los ntawm cov neeg muag khoom. Yog li ntawd, tus nqi ntawm cov khoom siv tshuaj khib nyiab qhuav tseem tseem siab, thiab nws yog qhov nyuaj rau kev txhawb nqa cov masonry zoo tib yam thiab plastering mortars nrog ntau qhov ntau thiab dav. Cov khoom lag luam siab kawg yog tswj hwm los ntawm cov tuam txhab txawv teb chaws, thiab cov chaw tsim khoom qhuav-siv mortar muaj cov txiaj ntsig tsawg thiab tsis zoo rau tus nqi; daim ntawv thov ntawm admixtures tsis muaj kev tshawb fawb thiab tsom, thiab blindly ua raws cov qauv txawv teb chaws.
Dej tuav tus neeg sawv cev yog ib qho tseem ceeb admixture los txhim kho cov dej tuav kev ua tau zoo ntawm cov khoom siv khib nyiab qhuav, thiab nws kuj yog ib qho ntawm cov khoom tseem ceeb uas txiav txim siab tus nqi ntawm cov khoom siv khib nyiab qhuav. Lub luag haujlwm tseem ceeb ntawm cellulose ether yog khaws dej.
Cellulose ether yog cov ntsiab lus dav dav rau cov khoom lag luam tsim los ntawm cov tshuaj tiv thaiv ntawm alkali cellulose thiab etherifying tus neeg sawv cev nyob rau hauv qee yam mob. Alkali cellulose yog hloov los ntawm cov neeg ua haujlwm sib txawv kom tau txais cov cellulose ethers sib txawv. Raws li cov khoom ionization ntawm cov khoom hloov, cellulose ethers tuaj yeem muab faib ua ob pawg: ionic (xws li carboxymethyl cellulose) thiab non-ionic (xws li methyl cellulose). Raws li hom kev hloov pauv, cellulose ether tuaj yeem muab faib ua monoether (xws li methyl cellulose) thiab sib xyaw ether (xws li hydroxypropyl methyl cellulose). Raws li qhov sib txawv solubility, nws tuaj yeem muab faib ua dej-soluble (xws li hydroxyethyl cellulose) thiab organic solvent-soluble (xws li ethyl cellulose). Qhuav-sib xyaw mortar tsuas yog siv cov dej-soluble cellulose, uas tau muab faib ntxiv rau hauv hom ceev-soluble thiab ncua-soluble hom tom qab kho deg.