Lub viscosity ntawm hydroxypropyl methylcellulose, qhov zoo dua cov dej khaws cia. Viscosity yog qhov tseem ceeb parameter ntawm HPMC kev ua tau zoo. Tam sim no, sib txawv HPMC cov tuam ntxhab Siv cov qauv sib txawv thiab cov cuab yeej los ntsuas qhov viscosity ntawm HPMC. Cov hau kev tseem ceeb yog Haake Rotovisko, Woppller, Ubbelihde thiab Brookfield.
Rau tib cov khoom lag luam, cov tshuaj viscosity tau ntsuas los ntawm cov qauv sib txawv yog qhov sib txawv heev, thiab qee tus txawm ob npaug ntawm qhov sib txawv. Yog li ntawd, thaum piv cov viscosity, nco ntsoov ua nws ntawm tib txoj kev ntsuas, suav nrog qhov kub thiab lwm yam, thiab lwm yam.
Rau qhov loj me me, lub flexer rau particle, qhov zoo dua cov dej khaws cia. Tom qab cov ntu loj ntawm cellulose ethot tuaj nkag mus rau hauv kev sib cuag tam sim ntawd kom tiv thaiv cov khoom los tiv thaiv kev nkag mus tsis muaj dej lwg me me. Cov. Nws cuam tshuam heev rau cov dej khaws cia ntawm nws cov cellulose ether, thiab solubility yog ib qho ntawm cov cellulose ether. Fineness tseem yog ib qho kev ua tau tseem ceeb ntsuas ntawm methyl cellulose ether. Lub MC siv rau cov hmoov huv kom qhuav yuav tsum tau ua kom tau hmoov, thiab cov ntsiab lus dej qis kuj yuav tsum tau 20% txog 60% ntawm cov particle loj kom tsawg dua 63um. Cov txiaj ntsig zoo rau cov solubility ntawm hydroxypropyl methylculose ether. Kev ntxhib feem ntau yog granular, thiab nws yog ib qho yooj yim rau yaj hauv dej yam tsis muaj agglomeration, tab sis nws tsis haum rau siv hauv cov tshuaj khib. Nyob rau hauv cov hmoov chot, mc tau tawg tawm ntawm cov khoom noj qabentitious xws li aggregates, nplua fillers thiab cement. Tsuas yog cov hmoov zoo txaus tuaj yeem zam kev agglomeration ntawm methyl cellulose ether thaum sib tov nrog dej. Thaum MC tau ntxiv nrog dej kom yaj cov agglomerates, nws yog qhov nyuaj rau kev ntiab tawm thiab yaj. MC nrog coarser fineness tsis yog pov tseg tsuas yog pov tseg, tab sis kuj yuav txo lub zog ntawm lub tshuaj khib. Thaum xws li cov hmoov av qhuav tau tsim hauv thaj chaw loj, kev kho kom huv ntawm lub ncoo hmoov tsis zoo, thiab tawg tshwm sim vim muaj kev kho lub sijhawm sib txawv. Rau cov tshuaj khib nyiab uas siv cov neeg siv tshuab kev tsim kho, vim yog lub sijhawm luv luv, yog qhov yuav tsum tau ua kom siab dua.
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 ntawm MC, qhov kev sib raug zoo ntawm cov solubility, uas muaj qhov tsis zoo ntawm lub zog thiab kev tsim kho ntawm lub tshuaj khib. Qhov siab tshaj lub viscosity, qhov pom ntau ntxiv rau cov nyhuv tuab ntawm lub tshuaj khib, tab sis nws tsis yog ib feem. Qhov siab tshaj lub viscosity, ntau lo nplaum dua cov cug cug yuav ua. Thaum lub sijhawm kev tsim kho, nws yuav lo rau cov scraper thiab muaj cov nplaum siab rau lub substrate. Tab sis nws me me kom nce cov txheej txheem lub zog ntawm lub txiv ntoo qhuav nws tus kheej. Thaum kev tsim kho, kev ua haujlwm ntawm kev tawm tsam sagging tsis pom tseeb. Ntawm qhov tsis sib xws, qee qhov tsawg-viscosity tab sis hloov kho methyl cellulose cellulose kev ua tau zoo tshaj plaws hauv kev txhim kho lub zog ntawm cov tshuaj khib.
Qhov loj dua tus nqi ntawm cellulose ether ntxiv rau hauv lub tshuaj khib, kom zoo dua cov dej ua kom ua tau zoo, ntau dua cov viscosity, qhov zoo dua cov dej khaws cia.
Lub txiaj ntsig ntawm HPMC kuj muaj qee yam cuam tshuam ntawm nws cov dej khaws cia. Feem ntau hais lus, rau methyl cellulose muaj kev hais nrog tib viscosity tab sis txawv qhov sib txawv, cov finer lub txiaj ntsig, qhov zoo dua cov txiaj ntsig khaws cia.
Cov dej khaws cia ntawm HPMC kuj tseem cuam tshuam nrog qhov kub siv, thiab cov dej tuav tseg ntawm methyl cellulose nrog qhov kub ntawm kub. Txawm li cas los xij, nyob rau hauv cov ntawv thov siv, muab cov hmoov av qhuav feem ntau siv rau cov chaw kub, uas feem ntau ua kom nrawm dua ntawm cov cement thiab ua kom zoo nkauj ntawm cug cug qhuav. Qhov poob hauv kev ua kom muaj zog hauv dej tau ua rau pom tseeb tias ob qho tib si ua haujlwm thiab tawg yog cuam tshuam rau txo cov txiaj ntsig ntawm cov xwm txheej ntawm cov xwm txheej zoo li no. Txawm hais tias methyl hydrotyl cellulose cellulose ethers yog tam sim no tau txiav txim siab yog qhov tseeb ntawm kev txhim kho thev naus laus zis tseem tuaj yeem ua rau cov tshuaj khib qhuav. Txawm hais tias tus nqi ntawm methyl hydrothethyl cellulose (lub caij ntuj sov formula) tau nce, lub zog ua haujlwm thiab tawg tsis tuaj yeem ua tau raws li kev xav tau. Los ntawm qee qhov kev kho mob tshwj xeeb, xws li nce qib siab, MC tuaj yeem khaws nws cov dej khov, yog li nws tuaj yeem muab kev ua tau zoo hauv qab.
Lub Sijhawm Post: Feb-20-2025