1 Taw qhia
Cov khoom siv casent-bas yog tam sim no cov khoom siv colishing tshwj xeeb, cov hmoov av loj, cov hmoov av cov kua txiv lossis lwm yam organic lossis inorganic ntxiv sib xyaw. Feem ntau, nws tsuas yog xav tau sib xyaw nrog dej thaum siv. Piv nrog dog dig colut, nws tuaj yeem txhim kho txoj kev sib raug zoo ntawm cov khoom siv thiab cov ntaub so ntswg tsis kam thiab cov dej tsis kam ua haujlwm. Nws yog tsuas yog siv los muab tshuaj txhuam cov khoom zoo xws li cov phab ntsa sab hauv thiab sab nraud, chav tsev, chav ua noj thiab lwm qhov chaw kho kom zoo nkauj. Tam sim no nws yog cov khoom siv tile dilting.
Feem ntau thaum peb txiav txim rau kev ua yeeb yam ntawm cov nplais nplaum, peb tsis tsuas yog them rau kev ua haujlwm thiab kev tawm tsam kev ua haujlwm, tab sis kuj tseem ua tib zoo mloog nws lub zog kho zog thiab qhib lub sijhawm. Cellulose ether hauv cov nplais nplaum tsis yog cuam tshuam rau cov khoom siv hluav taws xob tsis zoo, tab sis kuj tseem muaj cov khoom siv hluav taws xob, tab sis kuj tseem muaj cov khoom muaj zog ntawm cov pobzeb nplaum
2. Qhov cuam tshuam rau lub sijhawm qhib ntawm cov nplais nplaum
Thaum roj hmab hmoov thiab cellulose ether can-ether ether pom tias roj hmab muaj zog ntau dua nyob rau hauv lub caperstitial thiab teeb sijhawm. Lub nro ntawm cellulose ether yog siab dua li ntawm cov roj hmab hmoov av, thiab ntau dua cellule interface yuav muaj txiaj ntsig zoo rau kev tsim ntawm cov kab hlau thiab cellulose ether.
Hauv lub tshuaj khib ntub, cov dej hauv lub tshuaj khib nyiab hauv lub cell evaporates, thiab lub cellulose ether yog enrice egaporation tus nqi, li ntau dej ntxiv Muab tshem tawm los ntawm cov ntaub pua plag tuab ntawm nws migrates rau lub pinner cug txheej, thiab tsiv teb tsaws, thiab tsiv teb chaws ntawm dej ether txhawb rau ntawm lub tshuaj khib.
Yog li ntawd, zaj duab xis tsim ntawm cellulose ether nyob rau saum npoo ntawm cug cug muaj qhov cuam tshuam zoo ntawm kev tshuaj khib. 1) Cov yeeb yaj kiab tsim tau dhau heev thiab yuav tau yaj ob zaug, uas tsis tuaj yeem txwv cov dej evaporation thiab txo lub zog. 2) Cov yeeb yaj kiab tsim yog tuab heev, lub concentration ntawm cellulose ua kua siab, yog li nws tsis yooj yim los tsoo cov yeeb yaj kiab saum npoo thaum cov vuas yog pasted. Nws tuaj yeem pom tau tias cov yeeb yaj kiab ua yeeb yam ntawm cellulose ether tau cuam tshuam rau lub sijhawm qhib. Hom ntawm cellulose ether (HPMC, Hemm, Hems (hloov chaw) thiab qib siab ntawm cov yeeb yaj kiab ether, thiab kev nyuaj thiab tawv ntawm zaj duab xis.
3. Tus cawv ntawm lub zog nqus tau
Ntxiv rau qhov ua kom pom cov txiaj ntsig saum toj saud kom tshuaj khib, cellulose ether tseem tuaj cov mineting kinetics ntawm cov cement. Qhov nyhuv retarding no yog feem ntau vim yog cov adsorption ntawm cellule cov khoom siv ither tau adsorbed rau ntau yam li CSHS thiab calciumide. Ntawm cov tshuaj lom neeg, nws tsis tshua muaj adsorbed ntawm thawj cov chaw ntxhoo ntawm clinker. Tsis tas li ntawd, cellulose ether txo lub zog ntawm ions (CA2-, yog li cov kev daws teeb meem, yog li txuas ntxiv ncua cov txheej txheem hydration.
Viscosity yog lwm qhov tseem ceeb parameter, uas sawv cev rau cov tshuaj lom neeg ntawm cellulose ether. Raws li tau hais los saum no, lub viscosity tsuas yog cuam tshuam rau lub peev xwm kav dej thiab tseem muaj cov txiaj ntsig tseem ceeb ntawm kev ua haujlwm ntawm cov cug cug. Txawm li cas los xij, kev sim tshawb pom tau pom tias cov viscosity ntawm cellulose ether muaj yuav luag tsis cuam tshuam rau Minas hulation kinetics. Molecular hnyav muaj cov nyhuv me me ntawm kev haus dej, thiab qhov hnyav tshaj plaws ntawm cov hnyav hnyav molecular tsuas yog 10min. Yog li ntawd, qhov hnyav molecular tsis yog qhov tseem ceeb ntsuas tswj kev tswj hwm txoj cai xis.
Kev ua haujlwm ntawm lub cellulose ether nyob ntawm nws cov qauv tshuaj, rau MHEC, qib siab dua cov nyhuv retarding ntawm cellulose ether. Tsis tas li ntawd, cov nyhuv retarding ntawm hydrophilic hloov (xws li hloov chaw rau HEC) muaj zog dua li ntawm Hydrophobic hloov (xws li hloov chaw rau MH, MHEC, MHPC). Kev ua kom raug retarding ntawm cellulose ether tsuas cuam tshuam los ntawm ob qho tsis muaj, hom thiab ntau thiab ntau ntawm cov pab pawg hloov chaw.
Peb cov kev sim ua haujlwm hauv kev ua haujlwm kuj pom tias cov ntsiab lus ntawm cov neeg hloov chaw yog lub luag haujlwm tseem ceeb hauv kev siv zog ntawm cov nplais nplaum. Peb ntsuas kev ua tau zoo ntawm HPMC nrog cov qib sib txawv ntawm cov pab pawg sib txawv ntawm cov khoom sib txawv ntawm cov khoom siv tshuab ntawm cov nplais nplaum.
Hauv kev sim, peb xav txog HPMC, uas yog compoget ether, yog li peb yuav tsum muab ob daim duab ua ke. Rau HPMC, nws xav tau qee qib ntawm kev nqus kom ntseeg tau tias nws cov dej solubility thiab teeb meem kev hloov chaw. Peb paub cov ntsiab lus ntawm kev hloov chaw nws kuj txiav txim siab cov khoom kub thiab txias ntawm HPMC, uas txiav txim siab siv ib puag ncig HPMC. Nyob rau hauv txoj kev no, cov pab pawg cov ntsiab lus ntawm HPMC uas feem ntau siv tau kuj yog framed nyob rau hauv ib tug ntau. Nyob rau hauv no ntau, yuav ua li cas sib txuas methoxy thiab hydroxyprropoxy thiaj li ua tiav qhov zoo tshaj plaws yog cov ntsiab lus ntawm peb kev tshawb fawb. Daim duab 2 qhia tau nyob rau hauv qee qhov ntau, muaj kev nce ntxiv ntawm cov pab pawg methhoyl yuav ua rau cov ntsiab lus rub tawm hauv lub zog ntawm hydroxyl yuav ua rau muaj kev nce ntxiv ntawm lub zog rub tawm Cov. Muaj cov txiaj ntsig zoo sib xws rau kev qhib teev.
Qhov hloov pauv ntawm kev kho tshuab muaj zog nyob rau lub sijhawm qhib lub sijhawm yog ua raws li qhov ntawd tsis tshua muaj xwm txheej kub. HPMC nrog cov methoxyl (DS) cov ntsiab lus thiab tsawg hydroxyprropoxyl (MS) Cov ntsiab lus muaj cov tshuaj khib nyiab zoo nkauj, tab sis nws yuav cuam tshuam rau cov tshuaj pleev ntub ntawm qhov tsis sib xws. Cov khoom ntub dej cov khoom.
Lub Sijhawm Post: Jan-09-2023