Cement-raws li ceramic pobzeb nplaum yog tam sim no qhov loj tshaj plaws ntawm daim ntawv thov tshwj xeeb qhuav sib tov mortar, uas yog ib yam ntawm cov cement ua cov khoom siv cementing tseem ceeb thiab ntxiv los ntawm kev sib sau ua ke, dej tuav tus neeg saib xyuas, tus neeg sawv cev thaum ntxov, latex hmoov thiab lwm yam organic lossis inorganic. cov khoom xyaw. Feem ntau tsuas yog siv nrog cov dej sib xyaw, piv nrog cov cement mortar zoo tib yam, tuaj yeem txhim kho lub zog sib txuas ntawm cov khoom tiav thiab cov khoom siv hauv paus, muaj kev tiv thaiv zoo thiab muaj dej zoo heev, tiv thaiv tshav kub thiab khov-thawing voj voog zoo, feem ntau yog siv. rau pasting lub tsev sab hauv thiab sab nrauv phab ntsa vuas, pem teb vuas thiab lwm yam ntaub ntawv kho kom zoo nkauj, Nws yog dav siv nyob rau hauv kho kom zoo nkauj ntawm phab ntsa, pem teb, chav dej, chav ua noj thiab lwm lub tsev. Nws yog cov khoom siv dav siv ntau tshaj plaws ceramic pobzeb bonding khoom.
Feem ntau thaum peb txiav txim siab qhov kev ua tau zoo ntawm cov pobzeb ceramic nplaum, ntxiv rau kev them nyiaj rau nws cov kev ua haujlwm, kev tiv thaiv zawv zawg muaj peev xwm, tab sis kuj them sai sai rau nws lub zog txhua yam thiab lub sijhawm qhib. Cellulose ether ntawm cov nplais pobzeb nplaum ntxiv rau qhov cuam tshuam rau cov khoom siv ntawm cov plooj (porcelain kua nplaum), xws li kev ua haujlwm du, qhov teeb meem ntawm rab riam, tab sis kuj muaj cov khoom siv ntawm cov nplais pobzeb nplaum muaj zog.
1. Qhibsij hawm
Thaum cov hmoov roj hmab thiab cov cellulose ether sib koom ua ke hauv cov khib nyiab ntub dej, qee cov ntaub ntawv qauv qhia tias cov hmoov roj hmab muaj zog kinetic zog los ua raws li cov khoom siv cement hydration, thiab cellulose ether muaj ntau nyob rau hauv cov kua dej sib txawv, uas cuam tshuam rau viscosity thiab teem sij hawm ntawm mortar. ntau. Qhov nro ntawm cellulose ether yog loj dua li ntawm cov hmoov roj hmab, thiab kev ua kom muaj ntau ntawm cellulose ether ntawm mortar interface yog qhov zoo rau kev tsim cov hydrogen bonds ntawm lub hauv paus dav hlau thiab cellulose ether.
Moisture evaporation los ntawm hauv cov khib nyiab ntub dej, mortar, cellulose ether nyob rau hauv qhov chaw enrichment, 5 feeb tuaj yeem tsim ib daim nyias nyias ntawm cov mortar, yuav txo cov evaporation tus nqi ntawm kev soj ntsuam, nrog dej ntau los ntawm slurry tuab ib feem ntawm cov evaporation. txav mus rau hauv mortar txheej yog thinner, qhib cov ntsiab lus ib nrab yaj thaum pib tsim ntawm daim nyias nyias, kev tsiv teb tsaws ntawm cov dej tuaj yeem nqa ntau ntxiv ntawm cellulose ether nyob rau hauv mortar ntawm qhov chaw.
Cov zaj duab xis tsim ntawm cellulose ether nyob rau saum npoo ntawm mortar muaj kev cuam tshuam zoo rau cov khoom ntawm mortar:
Ua ntej, zaj duab xis tsim yog nyias nyias, yuav yaj ob zaug, tsis tuaj yeem txwv cov evaporation ntawm dej, txo lub zog.
Qhov thib ob, qhov tsim ntawm zaj duab xis yog tuab heev, cellulose ether nyob rau hauv mortar gap kua concentration yog siab, viscosity, thaum lub ceramic pobzeb muab tshuaj txhuam yog tsis yooj yim rau tawg nto ntawm zaj duab xis.
Nws tuaj yeem pom tias cov yeeb yaj kiab tsim kev ua haujlwm ntawm cellulose ether muaj kev cuam tshuam zoo rau lub sijhawm qhib. Hom cellulose ether (HPMC, HEMC, MC, thiab lwm yam) thiab degree ntawm etherification (degree ntawm kev hloov) ncaj qha cuam tshuam rau cov zaj duab xis tsim kev ua tau zoo ntawm cellulose ether, mus rau hardness thiab toughness ntawm zaj duab xis.
2, kos lub zog
Cellulose ether tsis tsuas yog endows mortar nrog rau tag nrho cov saum toj no cov khoom muaj txiaj ntsig, tab sis kuj ncua cov dej kinetics ntawm cov cement. Qhov kev cuam tshuam tsis zoo no feem ntau yog vim qhov adsorption ntawm cellulose ether molecules ntawm ntau theem ntxhia hauv cov cement system tau hydrated, tab sis nws feem ntau pom zoo tias cellulose ether molecules feem ntau yog adsorbed ntawm cov khoom siv dej xws li CSH thiab calcium hydroxide, thiab tsis tshua muaj adsorbed ntawm thawj cov ntxhia theem ntawm clinker. Tsis tas li ntawd, cellulose ether txo cov ions (Ca2+, SO42-, ...) vim muaj qhov viscosity ntawm pore daws. Kev ua hauv pore tov, uas ntxiv retards cov txheej txheem hydration.
Viscosity yog lwm qhov tseem ceeb, uas sawv cev rau cov tshuaj lom neeg ntawm cellulose ether. Raws li tau hais los saum no, viscosity feem ntau cuam tshuam rau lub peev xwm khaws dej, thiab tseem muaj feem cuam tshuam rau kev ua haujlwm ntawm cov tshuaj khib nyiab tshiab. Txawm li cas los xij, txoj kev tshawb nrhiav pom tias cov viscosity ntawm cellulose ether yuav luag tsis cuam tshuam rau cov dej kinetics ntawm cov cement. Qhov hnyav molecular muaj me ntsis cuam tshuam rau hydration, thiab qhov sib txawv loj tshaj plaws ntawm qhov sib txawv molecular hnyav tsuas yog 10min. Yog li ntawd, qhov hnyav molecular tsis yog qhov tseem ceeb ntawm kev tswj cov cement hydration.
"Cellulose ether nyob rau hauv cement raws li qhuav mix mortar khoom nyob rau hauv daim ntawv thov" qhia meej meej tias cellulose ether ncua nyob ntawm nws cov qauv tshuaj. Cov qauv dav dav yog tias rau MHEC, qhov siab dua ntawm cov tshuaj methylation, qhov me dua qhov cuam tshuam ntawm cellulose ether. Tsis tas li ntawd, kev hloov pauv hydrophilic (xws li hloov HEC) muaj qhov cuam tshuam zoo dua li kev hloov pauv hydrophobic (xws li hloov ntawm MH, MHEC thiab MHPC). Cov nyhuv retarding ntawm cellulose ether yog feem ntau cuam tshuam los ntawm ob qhov tsis muaj hom thiab tus naj npawb ntawm cov pab pawg hloov.
Peb qhov kev sim ua haujlwm tseem pom tau tias cov ntsiab lus ntawm cov neeg hloov pauv tau ua lub luag haujlwm tseem ceeb hauv lub zog txhua yam ntawm ceramic pobzeb nplaum. Peb tau soj ntsuam qhov kev ua tau zoo ntawm HPMC nrog ntau qib ntawm kev hloov pauv hauv cov nplais pobzeb nplaum, thiab kuaj qhov cuam tshuam ntawm cellulose ether uas muaj cov pab pawg sib txawv nyob rau hauv kev kho mob sib txawv ntawm cov khoom siv ntawm cov pobzeb ceramic nplaum. Kev cuam tshuam ntawm cov ntsiab lus ntawm DS thiab MS ntawm kev kos lub zog ntawm cov nplais pobzeb nplaum ntawm chav tsev kub.
HPMC yog ib qho kev sib xyaw ether, yog li txhawm rau muab ob daim duab ua ke, rau HPMC, yuav tsum muaj qib ntawm cov khoom siv, txhawm rau ua kom nws cov dej solubility thiab xa mus, peb paub tias cov ntsiab lus ntawm cov khoom hloov pauv kuj txiav txim siab qhov kub thiab txias ntawm HPMC. , uas yog txiav txim siab siv HPMC ib puag ncig, Hauv txoj kev no, pawg ntsiab lus ntawm HPMC yog framed nyob rau hauv ntau yam. Hauv ntau qhov no, yuav ua li cas muab methoxy thiab hydroxypropoxy kom ua tiav cov txiaj ntsig zoo tshaj plaws yog cov ntsiab lus ntawm peb txoj kev tshawb fawb. Hauv qee qhov ntau, qhov nce ntawm methoxy cov ntsiab lus yuav ua rau muaj kev poob qis ntawm kev nqus lub zog, thaum qhov nce ntawm hydroxypropoxy cov ntsiab lus yuav ua rau muaj kev nce qib ntawm kev nqus zog. Muaj qhov cuam tshuam zoo sib xws rau lub sijhawm qhib.
Post lub sij hawm: Dec-20-2021