Kev faib tawm ntawm Cellulose Ether
Cellulose ether yog ib lo lus dav dav rau cov khoom tsim los ntawm cov tshuaj tiv thaiv ntawm alkali cellulose thiab etherifying agent nyob rau hauv qee qhov xwm txheej. Thaum alkali cellulose raug hloov los ntawm cov neeg sawv cev etherifying sib txawv, cov cellulose ethers sib txawv yuav tau txais.
Raws li cov khoom ionization ntawm cov substituents, cellulose ethers tuaj yeem muab faib ua ob pawg: ionic (xws li carboxymethyl cellulose) thiab nonionic (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 solubility (xws li hydroxyethyl cellulose) thiab organic solvent solubility (xws li ethyl cellulose).
Cov cellulose ethers uas yaj tau hauv dej siv rau hauv cov mortars qhuav sib xyaw yog muab faib ua cov cellulose ethers uas yaj sai thiab cov cellulose ethers uas kho qhov chaw qeeb.
Lawv qhov sib txawv nyob qhov twg? Thiab yuav ua li cas kom nws du thiab yooj yim rau kev kuaj viscosity hauv 2% aqueous kua?
Kev kho qhov chaw yog dab tsi?
Cov nyhuv rau cellulose ether?
thawj zaug
Kev kho qhov chaw yog ib txoj kev los tsim ib txheej saum npoo ntawm qhov chaw ntawm cov khoom siv hauv paus nrog cov khoom siv kho tshuab, lub cev thiab tshuaj lom neeg sib txawv ntawm lub hauv paus.
Lub hom phiaj ntawm kev kho qhov chaw ntawm cellulose ether yog kom ncua lub sijhawm ntawm kev sib xyaw cellulose ether nrog dej kom tau raws li qhov xav tau qeeb ntawm qee cov xim pleev xim, thiab tseem yuav ua rau kom muaj kev tiv thaiv corrosion ntawm cellulose ether thiab txhim kho kev ruaj khov ntawm kev khaws cia.
Qhov sib txawv thaum dej txias raug teeb tsa nrog 2% cov kua dej:
Cov cellulose ether uas kho saum npoo av tuaj yeem tawg sai sai hauv dej txias thiab tsis yooj yim rau agglomerate vim nws cov viscosities qeeb;
Cellulose ether tsis muaj kev kho saum npoo, vim nws cov viscosities ceev, yuav viscous ua ntej nws tag nrho dispersed hauv dej txias, thiab yog ib qho yooj yim agglomeration.
Yuav ua li cas teeb tsa cov cellulose ether uas tsis kho qhov chaw?
1. Ua ntej muab ib qho ntawm cov cellulose ether uas tsis tau kho saum npoo av rau hauv;
2. Tom qab ntawd ntxiv dej kub ntawm li 80 degrees Celsius, qhov hnyav yog ib feem peb ntawm qhov ntim dej xav tau, yog li nws tuaj yeem o thiab tawg tag;
3. Tom ntej no, maj mam nchuav dej txias rau hauv, qhov hnyav yog ob feem peb ntawm cov dej seem uas xav tau, txuas ntxiv do kom nws nplaum maj mam, thiab yuav tsis muaj kev sib sau ua ke;
4. Thaum kawg, nyob rau hauv qhov xwm txheej ntawm qhov hnyav sib npaug, muab tso rau hauv lub dab dej kub tas mus li kom txog thaum qhov kub poob rau 20 degrees Celsius, thiab tom qab ntawd qhov kev sim viscosity tuaj yeem nqa tawm!
Lub sijhawm tshaj tawm: Lub Ob Hlis-02-2023