Qhov siab dua qhov viscosity ntawmHydroxypropyl methylcellulose yog ib qho khoom siv zoo, qhov zoo dua cov dej tuav kev ua haujlwm.Viscosity yog qhov tseem ceeb ntawm HPMC kev ua haujlwm.Tam sim no, cov tuam txhab HPMC sib txawv siv cov kev sib txawv thiab cov cuab yeej los ntsuas qhov viscosity ntawm HPMC.Cov txheej txheem tseem ceeb yog Haake Rotovisko, Hoppler, Ubbelohde thiab Brookfield.
Rau tib yam khoom, cov txiaj ntsig viscosity ntsuas los ntawm ntau txoj kev sib txawv heev, thiab qee qhov txawm tias ob npaug qhov sib txawv.Yog li ntawd, thaum sib piv viscosity, nco ntsoov ua nws ntawm tib txoj kev sim, suav nrog kub, rotor, thiab lwm yam.
Rau particle loj, qhov finer particle, qhov zoo dua cov dej tuav.Tom qab cov khoom loj ntawm cellulose ether tuaj rau hauv kev sib cuag nrog dej, qhov saum npoo dissolves tam sim ntawd los ua ib lub gel, uas qhwv cov ntaub ntawv los tiv thaiv kev tsis tu ncua ntawm cov dej molecules..Nws cuam tshuam rau cov dej tuav cov nyhuv ntawm nws cov cellulose ether, thiab solubility yog ib qho tseem ceeb ntawm kev xaiv cellulose ether.Fineness kuj yog ib qho tseem ceeb Performance index ntawm methyl cellulose ether.MC siv rau qhuav hmoov mortar yog yuav tsum tau hmoov, nrog dej tsawg, thiab cov fineness kuj yuav tsum tau 20% mus rau 60% ntawm particle loj yuav tsum tsawg tshaj li 63um.Fineness cuam tshuam rau solubility ntawm hydroxypropyl methylcellulose ether.Coarse MC feem ntau yog granular, thiab nws yog ib qho yooj yim rau yaj nyob rau hauv dej tsis muaj agglomeration, tab sis lub dissolution tus nqi qeeb heev, yog li nws tsis haum rau siv nyob rau hauv qhuav mortar.Nyob rau hauv qhuav hmoov mortar, MC yog dispersed ntawm cov cementitious cov ntaub ntawv xws li aggregates, nplua fillers thiab cement.Tsuas yog cov hmoov zoo txaus tuaj yeem zam cov agglomeration ntawm methyl cellulose ether thaum sib tov nrog dej.Thaum MC ntxiv nrog dej kom yaj cov agglomerates, nws nyuaj rau disperse thiab yaj.MC nrog coarser fineness tsis yog tsuas yog khib nyiab, tab sis kuj txo lub zog hauv zos ntawm mortar.Thaum xws li cov hmoov qhuav mortar yog tsim nyob rau hauv ib cheeb tsam loj, kev kho ceev ntawm lub zos qhuav hmoov mortar yog txo, thiab tawg tshwm sim vim lub sij hawm sib txawv.Rau cov tshuaj tsuag mortar siv txhua yam kev tsim kho, vim lub sij hawm luv luv stirring, lub fineness yuav tsum tau siab dua.
Feem ntau hais lus, qhov siab dua qhov viscosity, qhov zoo dua cov dej tuav.Txawm li cas los xij, qhov siab dua qhov viscosity thiab siab dua qhov hnyav molecular ntawm MC, qhov sib txuam txo ntawm nws cov solubility, uas muaj kev cuam tshuam tsis zoo rau lub zog thiab kev tsim kho ntawm mortar.Qhov siab dua qhov viscosity, qhov pom tseeb dua cov nyhuv ntawm cov tshuaj khib nyiab, tab sis nws tsis yog proportional.Qhov siab dua qhov viscosity, cov nplaum nplaum yuav ntau dua.Thaum lub sij hawm tsim kho, nws yuav lo rau lub scraper thiab muaj siab adhesion rau lub substrate.Tab sis nws ua me ntsis kom nce lub zog ntawm cov mortar ntub nws tus kheej.Thaum lub sij hawm tsim kho, qhov kev ua tau zoo ntawm kev tiv thaiv sagging tsis pom tseeb.Ntawm qhov tsis sib xws, qee qhov qis-viscosity tab sis hloov kho methyl cellulose ethers muaj kev ua tau zoo hauv kev txhim kho lub zog ntawm cov khoom ntub dej.
Qhov loj dua cov cellulose ether ntxiv rau hauv mortar, qhov dej tuav tau zoo dua, qhov viscosity siab dua, cov dej tuav tau zoo dua.
Qhov zoo ntawm HPMC kuj muaj qee yam cuam tshuam rau nws cov dej tuav.Feem ntau hais lus, rau methyl cellulose ethers nrog tib viscosity tab sis txawv fineness, nyob rau hauv cov ntaub ntawv ntawm tib qhov ntxiv, qhov finer lub fineness, qhov zoo dua cov dej tuav nyhuv.
Cov dej tuav ntawm HPMC kuj muaj feem xyuam rau qhov kub thiab txias siv, thiab cov dej tuav ntawm methyl cellulose ether txo qis nrog qhov kub thiab txias.Txawm li cas los xij, hauv kev siv cov khoom siv, cov hmoov qhuav mortar feem ntau yog siv rau kub substrates ntawm qhov kub thiab txias (siab tshaj 40 degrees) nyob rau hauv ntau qhov chaw, xws li sab nrauv phab ntsa putty plastering nyob rau hauv lub hnub nyob rau hauv lub caij ntuj sov, uas feem ntau accelerates curing ntawm xis mas thiab hardening. qhuav mortar.Kev poob hauv dej tuav tau ua rau muaj kev nkag siab meej tias ob qho tib si kev ua haujlwm thiab kev ua haujlwm tawg tau cuam tshuam, thiab nws yog qhov tseem ceeb tshwj xeeb los txo cov txiaj ntsig ntawm qhov kub thiab txias hauv cov xwm txheej zoo li no.Txawm hais tias methyl hydroxyethyl cellulose ether additive yog tam sim no suav hais tias yog qhov ua ntej ntawm kev txhim kho thev naus laus zis, nws qhov kev cia siab ntawm qhov kub thiab txias tseem tuaj yeem ua rau tsis muaj zog ntawm cov tshuaj khib nyiab qhuav.Txawm hais tias tus nqi ntawm methyl hydroxyethyl cellulose (lub caij ntuj sov mis) yog nce, kev ua hauj lwm thiab tawg kuj tseem tsis tau raws li qhov xav tau ntawm kev siv.Los ntawm qee qhov kev kho tshwj xeeb, xws li nce qib ntawm etherification, MC tuaj yeem ua kom nws cov dej tuav tau zoo dua ntawm qhov kub siab dua, kom nws tuaj yeem muab kev ua tau zoo dua hauv cov xwm txheej hnyav.
Post lub sij hawm: Oct-20-2022