Lub luag haujlwm tseem ceeb ntawm cellulose ether hauv cug

Cellulose ether tuaj yeem txhim kho kev ua tau zoo ntawm cov tshuaj khib ntub, thiab yog lub ntsiab additive uas cuam tshuam kev tsim kho ntawm cug. Cov kev xaiv tsim nyog ntawm cellulose tsim muaj ntau yam, txawv cov viscetle, sib txawv yuav muaj kev sib txawv ntawm kev txhim kho ntawm kev ua kom qhuav. Tam sim no muaj ntau masonry thiab plastering mortars muaj cov dej tsis zoo, thiab cov dej slurry yuav cais tom qab ob peb feeb ntawm sawv ntsug. Dej khaws cia yog ib qho kev ua tau tseem ceeb ntawm methyl cellulose ether, tshwj xeeb yog cov cheeb tsam sib xyaw nrog ntau qhov kub thiab txias, xyuam xim rau. Yam uas cuam tshuam rau cov nyhuv retentive ntawm cov kab laum hmoov kom qhuav, cov ntau ntawm cov hais, thiab ntsuas kub ntawm kev siv ib puag ncig.

Dej tuav tseg ntawm cellulose ether

Hauv kev tsim cov ntaub ntawv hauv tsev, tshwj xeeb tshaj yog cov hmoov av, cellulose ua lub luag haujlwm (cug cug Lub luag haujlwm tseem ceeb ntawm cov dej-soluble cellulose ether nyob rau hauv cug yog muaj peb qhov yog qhov sib xyaw ua ke, thiab qhov thib peb yog kev sib cuam tshuam nrog cov cement. Cov dej khaws cov nyhuv ntawm cellulose nyob ntawm cov txheej txheem dej, cov dej phib tawj, cov dej phib tawj, thiab lub sijhawm teeb tsa lub sijhawm teeb tsa. Cov dej khaws cia ntawm cellulose ether nws tus kheej los ntawm solubility thiab lub cev qhuav dej ether nws tus kheej. Raws li peb txhua tus paub, txawm hais tias lub cellulose molecular saw muaj ntau ntawm hydratle hel pawg, vim hais tias lub cellulose qauv muaj qhov siab ntawm crystallinity. Cov hydration muaj peev xwm ntawm pawg hydroxyl ib leeg yog tsis txaus los npog qhov muaj zog hydrogen bonds thiab van der waals rog ntawm molecules. Yog li ntawd, nws tsuas yog swells tab sis tsis yaj hauv dej. Thaum tus hloov pauv tau rau hauv cov molecular chart, tsis tsuas yog cov kev sib tw hydrogen puas tsuaj yog rhuav tshem vim kev sib tw ntawm cov kev sib tw ntawm cov saw hlau. Cov loj dua cov neeg hloov pauv, qhov kev ncua deb ntawm cov lwg me me. Qhov ntau dua qhov deb. Qhov ntau dua cov txiaj ntsig ntawm kev rhuav tshem hydrogen bonds, lub cellulose bonded dej-soluble tom qab lub cellulose daws teeb meem siab. Thaum qhov kub nce, cov hydration ntawm cov polymer muaj zog tsis muaj zog, thiab cov dej ntawm txoj saw hlau tau tsav tawm. Thaum lub cev qhuav dej ua tau txaus, cov lwg me me pib sib sau ua ke, ua ib qho cuab yeej cuab tam sim no thiab tais diav.

Feem ntau hais lus, ntau dua cov viscosity, qhov zoo dua cov dej khaws cov nyhuv khaws cia. Txawm li cas los xij, qhov ntau dua cov viscosity thiab ntau dua cov molecular hnyav, qhov txo qis hauv nws solubility yuav muaj kev tsis zoo rau lub zog thiab kev tsim kho ntawm lub tshuaj khib. Qhov siab tshaj lub viscosity, qhov pom ntau ntxiv rau cov nyhuv tuab rau ntawm lub tshuaj khib, tab sis nws tsis ncaj ncaj ncaj. Qhov siab tshaj lub viscosity, ntau ntau ntau lub cug cug cug yuav ua, uas yog, thaum lub sijhawm tsim, nws yog manifested raws li straper thiab siab adhesion rau lub substrate. Tab sis nws tsis muaj txiaj ntsig zoo rau kev nce cov txheej txheem lub zog ntawm lub txiv ntoo qhuav nws tus kheej. Thaum kev tsim kho, kev ua haujlwm tsis zoo yog tsis pom tseeb. Ntawm qhov tsis sib xws, qee qhov nruab nrab thiab qis viscosity tab sis hloov kho metyl cellulose cellulose kev ua tau zoo tshaj plaws hauv kev txhim kho lub zog ntawm cov tshuaj khib nyiab ntub dej.

Thickening thiab thixotropy ntawm cellulose ether

Kuj tseem muaj cov kab zoo zoo ntawm qhov sib xws ntawm cov cement muab tshuaj pleev thiab cov tshuaj ntawm cellulose ether. Cellulose ether tuaj yeem ua rau muaj viscosity heev ntawm cug. Qhov loj dua cov kev siv tshuaj, qhov tseeb pom tseeb. High-viscosity cellulose ethooure kua muaj siab thixotrostropy, uas tseem yog tus yam ntxwv loj ntawm cellulose ether.

Thickening nyob ntawm cov qib polymerization ntawm cellulization ntawm cellule ntawm cellule ether, kev daws teeb meem, ntsuas kub, kub thiab lwm yam. Cov cuab yeej ntawm cov kev daws teeb meem yog qhov tshwj xeeb rau alkyl cellulose thiab nws tau hloov cov derivatives. Cov khoom gelation muaj feem xyuam nrog rau qib degree hloov chaw, kev daws teeb meem thiab ntxiv. Rau hydroxyalkyl hloov cov derivatives, gel cov khoom tseem muaj feem cuam tshuam nrog kev hloov kho qib ntawm hydroxyalkyl. Rau qis viscosity MC thiab HPMC, 10% -15% kev daws teeb meem MC thiab HPMC tuaj yeem npaj cov tshuaj tua kab mob 2% thiab HPMC tuaj yeem npaj rau ntawm 1% kev daws teeb meem. High molecular hnyav cellulose muaj siab thicking efficiency. Hauv kev daws teeb meem tib yam, cov polymers nrog hnyav molecular hnyav muaj cov vascosities sib txawv. Siab degree. Lub hom phiaj viscosity tsuas yog ua tiav los ntawm kev ntxiv cov nyiaj ntau ntawm cov roj ntsha tsis muaj roj ether ether. Nws viscosity muaj cov neeg sib txawv me me ntawm cov shear tus nqi, thiab cov viscosity siab txog lub hom phiaj viscosity, thiab viscosity nyob ntawm lub xaim hluav taws xob. Yog li ntawd, kom ua tiav qhov xwm txheej, qee qhov nyiaj ntawm cellulose ether (concentration ntawm kev daws teeb meem) thiab daws viscosity yuav tsum lav. Lub gel kub ntawm kev daws teeb meem tseem txo qis linearly nrog kev nce ntawm cov kev daws teeb meem, thiab gels nyob rau hauv chav tsev kub tom qab ncav ib co siab. Qhov kev pom zoo ntawm HPMC yog qhov siab dua nyob rau hauv chav tsev kub.

Rov ua haujlwm ntawm cellulose ether

Qhov thib peb kev ua haujlwm ntawm cellulose ether yog ncua cov txheej txheem hydration ntawm cov cement. Cellulose ether Yuav cug nrog ntau yam tshuaj ntsuab, thiab kuj txo qhov kev ua kom dej sov thiab qeeb cov txheej txheem kev ua kom zoo nkauj ntawm cov cement. Qhov no tsis zoo rau kev siv tshuaj khib hauv cov cheeb tsam txias. Qhov kev ua tau zoo no tshwm sim los ntawm cov adsorption ntawm cellulose ether molecules ntawm cov khoom siv dej xws li CSH thiab Ca (Oh) 2. Vim tias qhov nce nyob rau hauv viscosity ntawm cov kab viscosity ntawm cov kab viscosity, lub cellulose ither txo lub ions hauv kev daws teeb meem, yog li ncua cov txheej txheem hydration. Qhov siab dua ntawm cellulose ntawm cellulose ntawm cellulose ntawm cov ntxhia cov khoom, ntau tshaj tawm cov nyhuv qeeb. Cellulose ether tsis tsuas yog chaw teeb tsa, tab sis kuj tseem noj cov txheej txheem tawv ntawm cov txiv neej collftion zog. Kev ua kom raug retarding cov nyhuv ether nyob ntawm tsis tsuas yog nyob ntawm nws cov kev xav hauv cov qauv ntxhia, tab sis kuj nyob rau cov qauv tshuaj. Qhov siab dua qib ntawm methylation ntawm HEMC, qhov zoo dua cov nyhuv retarding ntawm cellulose ether. Qhov sib piv ntawm Hydrophilic hloov chaw rau kev ua kom muaj kev nce qib kom rov ua kom muaj zog dua. Txawm li cas los xij, lub viscosity ntawm cellulose ether muaj me ntsis nyhuv rau Minas hulation kinetics.

Nyob rau hauv cap, cellulose ether ua lub luag haujlwm ntawm dej khaws cia, thickening, ncua cement hwj chim, thiab txhim kho kev tsim kho. Cov dej ua kom zoo ua rau muaj kev nthuav dav ua tiav, tuaj yeem txhim kho viscosity ntawm lub zog ntub dej ntawm cug, thiab kho lub sijhawm. Ntxiv cov cellulose ether rau cov tshuab txau muab tshuaj yuav txhim kho cov txau lossis nqus ntawm lub cug. Yog li ntawd, cellulose ether tau siv dav siv ua qhov tseem ceeb ntxiv nyob rau hauv kev txhaj tshuaj tshiab-mixed