Hydroxypropyl methylcellulose (HPMC)yog ib qho polymer uas yaj tau hauv dej uas feem ntau siv rau hauv cov ntaub ntawv siv hauv kev tsim kho. Nws siv dav hauv cov cement mortar, hmoov putty, nplaum pobzeb thiab lwm yam khoom. HPMC feem ntau txhim kho qhov zoo ntawm cov ntaub ntawv cement los ntawm kev ua kom lub viscosity ntawm lub kaw lus, txhim kho lub peev xwm khaws dej thiab kho qhov kev ua tau zoo ntawm kev tsim kho.
1. Cov nyhuv ntawm HPMC rau kev khaws dej ntawm cov cement mortar
Qhov kev khaws dej ntawm cov cement mortar txhais tau hais tias lub peev xwm ntawm cov mortar khaws dej ua ntej nws khov tag. Kev khaws dej zoo pab kom cov cement noo tag nrho thiab tiv thaiv kev tawg thiab kev poob zog los ntawm kev poob dej ntau dhau. HPMC txhim kho kev khaws dej ntawm cov cement mortar hauv cov hauv qab no:
Ua kom lub cev viscosity nce ntxiv
Tom qab HPMC yaj hauv cov cement mortar, nws tsim cov qauv mesh sib xws, ua rau cov mortar viscosity nce ntxiv, faib cov dej hauv cov mortar kom sib npaug thiab txo qhov poob ntawm cov dej dawb, yog li txhim kho kev khaws dej. Qhov no yog qhov tseem ceeb tshwj xeeb rau kev tsim kho kub siab thaum lub caij ntuj sov lossis rau cov txheej hauv paus nrog kev nqus dej zoo.
Tsim kom muaj ib qho dej noo thaiv
Cov tshuaj HPMC muaj cov dej nqus tau zoo, thiab nws cov kua tuaj yeem tsim cov zaj duab xis hydration nyob ib puag ncig cov cement, uas ua lub luag haujlwm hauv kev kaw dej thiab qeeb qeeb ntawm cov dej evaporation thiab nqus. Cov zaj duab xis dej no tuaj yeem tswj cov dej sib npaug hauv cov mortar, ua rau cov cement hydration reaction mus zoo.
Txo kev los ntshav
HPMC tuaj yeem txo qhov kev los ntshav ntawm cov mortar, uas yog, qhov teeb meem ntawm cov dej nag los ntawm cov mortar thiab ntab tom qab cov mortar sib xyaw. Los ntawm kev ua kom cov viscosity thiab qhov nro ntawm cov kua dej, HPMC tuaj yeem tiv thaiv kev tsiv teb tsaws chaw ntawm cov dej sib xyaw hauv cov mortar, xyuas kom meej tias cov dej sib faib sib npaug thaum lub sijhawm ua cov cement hydration, thiab yog li txhim kho qhov sib npaug thiab kev ruaj khov ntawm cov mortar.
2. Cov nyhuv ntawm HPMC rau ntawm cov khoom sib xyaw ntawm cov cement mortar
Lub luag haujlwm ntawm HPMC hauv cov cement mortar tsis yog txwv rau kev khaws cia dej, tab sis kuj cuam tshuam rau nws cov khoom sib xyaw thiab kev ua tau zoo, raws li qhia hauv qab no:
Cuam tshuam rau cov txheej txheem cement hydration
Qhov ntxiv ntawm HPMC yuav ua rau qeeb qeeb ntawm cov dej noo ntawm cov cement hydration thaum ntxov, ua rau cov txheej txheem tsim cov khoom hydration sib xws dua, uas yog qhov zoo rau kev ua kom cov qauv mortar ntom. Qhov kev ncua sij hawm no tuaj yeem txo qhov tawg ntawm cov khoom shrinkage thaum ntxov thiab txhim kho qhov tsis kam ntawm cov mortar.
Kho cov khoom rheological ntawm mortar
Tom qab yaj, HPMC tuaj yeem ua rau kom cov mortar plasticity thiab workability ntau dua, ua rau nws du dua thaum thov lossis tso, thiab tsis yooj yim los ntshav thiab sib cais. Tib lub sijhawm, HPMC tuaj yeem muab mortar ib qho thixotropy, yog li nws tswj tau qhov viscosity siab thaum sawv ntsug, thiab qhov fluidity tau txhim kho nyob rau hauv qhov kev ua ntawm shear force, uas yog pab tau rau kev ua haujlwm hauv kev tsim kho.
Kev cuam tshuam rau kev txhim kho lub zog ntawm mortar
Txawm hais tias HPMC txhim kho kev ua tau zoo ntawm cov mortar, nws kuj tseem yuav muaj qee qhov cuam tshuam rau nws lub zog kawg. Vim tias HPMC yuav tsim ib zaj duab xis hauv cov cement mortar, nws yuav ncua qhov kev tsim cov khoom hydration hauv lub sijhawm luv luv, ua rau lub zog thaum ntxov txo qis. Txawm li cas los xij, thaum cov cement hydration txuas ntxiv mus, cov dej noo uas HPMC khaws cia tuaj yeem txhawb nqa cov tshuaj tiv thaiv hydration tom qab, yog li lub zog kawg tuaj yeem txhim kho.
Ua ib qho khoom siv tseem ceeb rau cov cement mortar,HPMCtuaj yeem txhim kho qhov kev khaws dej ntawm cov pob zeb mortar, txo qhov dej poob, txhim kho kev ua haujlwm ntawm kev tsim kho, thiab cuam tshuam rau cov txheej txheem hydration cement rau qee qhov. Los ntawm kev kho qhov ntau npaum li cas ntawm HPMC, qhov sib npaug zoo tshaj plaws ntawm kev khaws dej, kev ua haujlwm tau zoo thiab lub zog tuaj yeem pom kom ua tau raws li qhov xav tau ntawm ntau yam kev siv. Hauv cov haujlwm tsim kho, kev siv HPMC kom raug yog qhov tseem ceeb heev rau kev txhim kho qhov zoo ntawm cov pob zeb mortar thiab txuas ntxiv lub zog.
Lub sijhawm tshaj tawm: Lub Peb Hlis-25-2025