Putty hmoov yog tsuas yog siv rau theem thiab kho phab ntsa thaum tsim kho. Txawm li cas los xij, cov hmoov putty ib txwm muaj rau kev tawg thiab muag muag thaum raug dej, cuam tshuam rau kev tsim kho kom zoo thiab kev pabcuam lub neej ntawm lub tsev. Hydroxypropyl methylcellulose (HPMC), ua ib qho tseem ceeb ntxiv, tuaj yeem txhim kho cov dej tsis kam ntawm putty hmoov.
1. Cov khoom siv tshuaj lom neeg thiab cov haujlwm tseem ceeb ntawm HPMC
Hydroxypropyl methylcellulose (HPMC) yog non-ionic cellulose ether nrog ntau lub zog xws li thickening, film-forming, stabilization, thiab ntub dej. Nws yog dav siv hauv cov khoom siv hauv tsev, tshuaj, zaub mov thiab lwm yam haujlwm. Cov qauv molecular ntawm HPMC muaj hydrophilic hydroxyl pawg (–OH) thiab hydrophobic hydrocarbon pawg (–CH3, –CH2–), muab cov dej zoo solubility thiab stability. Cov khoom no ua rau HPMC tsim cov kev daws teeb meem ruaj khov colloidal hauv dej thiab tsim kom muaj cov qauv sib txuas ntom ntom thaum lub sijhawm kho, yog li txhim kho lub cev ntawm cov khoom.
2. Mechanism los txhim kho dej tsis kam
2.1. Thickening nyhuv
HPMC tuaj yeem ua kom cov viscosity ntawm putty hmoov slurry, uas tso cai rau cov slurry tsim kom muaj kev ruaj ntseg ncua kev kawm ntawv hauv dej. Ntawm ib sab, cov nyhuv thickening no txhim kho kev tsim kho ntawm slurry thiab txo qhov tshwm sim ntawm delamination thiab los ntshav; ntawm qhov tod tes, los ntawm kev tsim cov viscous slurry, HPMC txo qhov nkag mus ntawm cov dej molecules, yog li txhim kho cov txiaj ntsig ntawm cov hmoov putty. Kev tiv thaiv dej tom qab kho.
2.2. Zaj duab xis-forming zog
Thaum lub sij hawm kho cov hmoov putty, HPMC yuav tsim ib zaj duab xis ntom ntom ntawm cov cement, dej thiab lwm yam khoom xyaw. Cov membrane no muaj cov dej vapor kis tau tus nqi tsawg thiab tuaj yeem thaiv qhov nkag mus ntawm cov dej noo. Cov yeeb yaj kiab tsim los ntawm HPMC tuaj yeem txhim kho lub zog txhua yam thiab hnav tsis kam ntawm cov khoom, ntxiv dag zog rau cov dej tsis kam ntawm cov hmoov putty.
2.3. Txhim kho kev tawg tsis kam
Los ntawm kev txhim kho cov elastic modulus thiab shrinkage zog ntawm putty hmoov, HPMC tuaj yeem txo qhov kev pheej hmoo ntawm kev tawg los ntawm kev qhuav shrinkage thiab kub hloov. Txo qhov tshwm sim ntawm cov kab nrib pleb kuj tseem yuav pab txhim kho cov dej tsis kam ntawm cov hmoov putty, vim tias cov kab nrib pleb yuav dhau los ua txoj hauv kev rau dej nkag.
2.4. Tswj cov tshuaj tiv thaiv hydration
HPMC tuaj yeem ncua sijhawm cov tshuaj tiv thaiv hydration ntawm cov cement, tso cai rau cov hmoov putty kom muaj sijhawm ntev rau nws tus kheej kho thiab densify thaum lub sij hawm hardening txheej txheem. Cov tshuaj tiv thaiv hydration qeeb pab tsim cov microstructure ntom, yog li txo cov porosity ntawm cov hmoov putty thiab txhim kho cov dej tsis zoo ntawm cov khoom.
3. Kev siv cov nyhuv ntawm HPMC hauv cov hmoov putty
3.1. Txhim kho kev tsim kho kev ua haujlwm
HPMC optimizes rheological zog ntawm putty slurry, ua kom yooj yim rau cov neeg ua hauj lwm tsim los ua scraping thiab smoothing hauj lwm. Vim nws cov thickening zoo heev thiab cov dej tuav cov khoom, cov hmoov putty tuaj yeem tuav lub xeev tsim nyog moist thaum thov, txo qhov tshwm sim ntawm qhuav tawg thiab txhim kho kev tsim kho.
3.2. Txhim kho cov khoom siv kho tshuab ntawm cov khoom tiav
Putty hmoov ntxiv nrog HPMC muaj lub zog txhua yam thiab adhesion tom qab kho, txo qhov muaj peev xwm tawg thiab tev. Qhov no ho txhim kho tag nrho kev zoo nkauj thiab durability ntawm lub tsev.
3.3. Txhim kho cov dej tsis kam ntawm cov txheej txheem kawg
Cov kev sim qhia tau hais tias lub zog ntawm putty hmoov ntxiv nrog HPMC txo qis me ntsis tom qab soaked hauv dej, thiab nws qhia tau hais tias zoo dua hydrolysis tsis kam thiab stability. Qhov no ua rau cov hmoov putty siv HPMC tsim nyog rau kev tsim kho kev xav tau nyob rau hauv qhov chaw ntub dej.
4. Daim ntawv thov ceev faj
Txawm hais tias HPMC muaj qhov cuam tshuam loj rau kev txhim kho cov dej tsis kam ntawm cov hmoov putty, cov ntsiab lus hauv qab no yuav tsum tau muab sau tseg hauv cov ntawv thov:
4.1. Xaiv cov tshuaj kom tsim nyog
Cov koob tshuaj ntawm HPMC yuav tsum tau kho kom haum raws li cov qauv thiab kev tsim kho ntawm cov hmoov putty. Kev siv ntau dhau yuav ua rau cov slurry ua kom khov heev, cuam tshuam rau kev tsim kho; Kev siv tsis txaus yuav tsis ua rau nws cov thickening thiab cov yeeb yaj kiab-forming teebmeem.
4.2. Synergy nrog lwm yam additives
HPMC feem ntau siv nrog rau lwm cov cellulose ethers, latex hmoov, plasticizers thiab lwm yam additives kom ua tiav cov txiaj ntsig zoo dua. Tsim nyog xaiv thiab sib piv ntawm cov additives no yuav optimize tag nrho cov kev ua tau zoo ntawm putty hmoov.
4.3. Tswj ambient kub thiab humidity
Cov dej tuav cov khoom ntawm HPMC yuav raug cuam tshuam thaum siv rau hauv qhov kub thiab txias los yog cov av qis. Kev tsim kho yuav tsum tau ua raws li qhov ntsuas kub thiab cov av noo kom ntau li ntau tau, thiab kev saib xyuas yuav tsum tau them nyiaj rau kev tswj cov dej noo ntawm slurry.
HPMC zoo txhim kho cov dej tsis kam ntawm cov hmoov putty los ntawm ntau lub tswv yim xws li thickening, tsim zaj duab xis, txhim kho kev sib tsoo thiab tswj cov tshuaj tiv thaiv dej, tso cai rau nws ua kom muaj kev ruaj ntseg zoo thiab ua haujlwm nyob rau hauv qhov chaw ntub dej. Qhov no tsis tsuas yog txhim kho qhov zoo thiab kev ua haujlwm ntawm kev tsim vaj tsev, tab sis kuj tseem txuas ntxiv lub neej kev pabcuam ntawm lub tsev. Hauv kev siv cov tswv yim, kev xaiv tsim nyog thiab siv HPMC thiab lwm yam khoom siv ntxiv tuaj yeem ua kom zoo dua ntawm cov hmoov putty thiab ua tiav cov txiaj ntsig zoo dua.
Post lub sij hawm: Jun-26-2024