Qhov siab dua qhov viscosity ntawm hydroxypropyl methylcellulose, qhov zoo dua cov dej tuav kev ua haujlwm. Viscosity yog ib qho tseem ceeb parameter ntawm HPMC kev ua tau zoo. 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 HaakeRotovisko, Hoppler, Ubbelohde thiab Brookfield.
Rau tib yam khoom, cov txiaj ntsig viscosity ntsuas los ntawm txoj kev sib txawv yog qhov sib txawv heev, thiab qee qhov muaj qhov sib txawv ob npaug. Yog li ntawd, thaum sib piv viscosity, nws yuav tsum tau nqa tawm ntawm tib txoj kev sim, xws li kub, rotor, thiab lwm yam.
Hais txog 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 chaw tam sim ntawd dissolves thiab tsim cov gel los qhwv cov khoom los tiv thaiv cov dej molecules los ntawm kev nkag mus ntxiv. Qee lub sij hawm nws tsis tuaj yeem sib cais thiab yaj txawm tias tom qab lub sij hawm ntev nplawm, tsim cov huab flocculent tov los yog agglomeration. Nws cuam tshuam rau cov dej tuav ntawm 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 cov hmoov qhuav mortar yuav tsum yog hmoov, nrog cov dej tsawg, thiab cov fineness kuj yuav tsum tau 20% -60% ntawm cov particle loj kom tsawg dua 63um. Lub 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 hmoov mortar.
Nyob rau hauv qhuav hmoov mortar, MC yog dispersed ntawm cementing cov ntaub ntawv xws li aggregate, nplua muab tub lim thiab cement, thiab tsuas yog hmoov zoo txaus yuav zam methyl cellulose ether agglomeration thaum tov nrog dej. Thaum MC ntxiv nrog dej kom yaj cov agglomerates, nws nyuaj heev rau disperse thiab yaj. Coarse fineness ntawm MC tsis yog tsuas yog khib nyiab, tab sis kuj txo lub zog hauv zos ntawm mortar. Thaum xws li cov hmoov qhuav mortar yog siv rau hauv ib cheeb tsam loj, kev kho ceev ntawm cov hmoov qhuav hauv zos yuav txo qis, thiab cov kab nrib pleb yuav tshwm sim vim lub sijhawm sib txawv. Rau cov tshuaj txau nrog cov khoom siv kho tshuab, qhov yuav tsum tau ua kom zoo yog siab dua vim lub sijhawm sib xyaw luv.
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 piv ntawm nws cov solubility yuav 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 thickening ntawm mortar, tab sis nws tsis ncaj qha proportional. Qhov siab dua qhov viscosity, qhov viscous ntau dua cov mortar ntub yuav, uas yog, thaum lub sij hawm tsim kho, nws yog manifested li sticking rau scraper thiab siab adhesion rau lub substrate. Tab sis nws tsis muaj txiaj ntsig los ua kom lub zog muaj zog ntawm cov mortar ntub nws tus kheej. Thaum lub sij hawm tsim kho, qhov kev ua tau zoo anti-sag tsis pom tseeb. Ntawm qhov tsis sib xws, qee qhov nruab nrab thiab 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 ntau dua ntawm cov cellulose ether ntxiv rau hauv mortar, qhov dej tuav tau zoo dua, thiab qhov viscosity siab dua, qhov 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 tib qhov sib ntxiv, qhov finer lub finer 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 tiag tiag, cov hmoov av qhuav feem ntau siv rau cov khoom kub kub ntawm qhov kub siab (siab dua 40 degrees) 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 cement thiab hardening. qhuav hmoov mortar.
Qhov poob ntawm cov dej tuav tus nqi ua rau pom pom tseeb 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 qhov cuam tshuam ntawm qhov kub thiab txias hauv qhov xwm txheej no. Txawm hais tias methyl hydroxyethyl cellulose ether additives yog tam sim no suav hais tias yog nyob rau hauv pem hauv ntej ntawm txoj kev loj hlob, lawv dependence rau kub tseem yuav ua rau tsis muaj zog ntawm kev ua tau zoo ntawm qhuav hmoov mortar.
Ua kom tus nqi ntawm methyl hydroxyethyl cellulose, workability thiab tawg kuj tseem tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev siv. Los ntawm qee qhov kev kho tshwj xeeb ntawm MC, xws li nce qib ntawm etherification, thiab lwm yam, cov dej tuav tau tuaj yeem tswj tau ntawm qhov kub siab dua, kom nws tuaj yeem muab kev ua tau zoo dua hauv cov xwm txheej hnyav.
Lub sij hawm xa tuaj: Plaub Hlis-10-2023