HPMC (hydroxypropyl methylcellulose) yog ib qho khoom siv polymer ntau yam uas siv dav hauv cov ntaub ntawv tsim kho, tshwj xeeb tshaj yog cov ntaub ntawv ua los ntawm cement. Kev siv HPMC tuaj yeem txhim kho kev ua tau zoo ntawm cov ntaub ntawv ua los ntawm cement, suav nrog kev txhim kho kev tiv thaiv kev tawg, txhim kho kev ua haujlwm thiab tswj cov txheej txheem hydration, yog li txo qhov tshwm sim ntawm kev tawg.
Cov khoom siv tshuaj lom neeg thiab lub cev ntawm HPMC
HPMC yog ib qho polymer semi-synthetic uas tau hloov kho los ntawm cellulose. Nws cov qauv molecular suav nrog methyl thiab hydroxypropyl substituents, muab nws cov khoom tshwj xeeb solubility, thickening, water retention thiab film-forming. Nws cov yam ntxwv tseem ceeb suav nrog:
Kev khaws dej siab: HPMC muaj peev xwm khaws dej zoo heev thiab tuaj yeem tsim cov zaj duab xis khaws dej hauv cov khoom kom qeeb qeeb ntawm kev ua pa ntawm dej.
Cov nyhuv thickening: HPMC tuaj yeem ua rau kom cov viscosity ntawm cov slurry ntau ntxiv, yog li txhim kho nws txoj haujlwm.
Cov yam ntxwv ntawm kev tsim zaj duab xis: Nws lub peev xwm zoo ntawm kev tsim zaj duab xis tuaj yeem tsim cov zaj duab xis yooj ywm rau ntawm qhov chaw ntawm cov khoom, muab kev tiv thaiv lub cev ntxiv.
Lub tshuab cuam tshuam ntawm HPMC rau kev tawg ntawm cov ntaub ntawv cement-based
1. Kev khaws dej thiab txo cov kab nrib pleb qhuav
Cov ntaub ntawv cementitious muaj qhov loj me me thaum lub sijhawm hardening, feem ntau yog vim dej poob thiab qhuav shrinkage vim yog cov tshuaj tiv thaiv hydration. Cov kab nrib pleb qhuav shrinkage feem ntau yog tshwm sim los ntawm kev ua kom sai ntawm cov dej hauv cov cement slurry thaum lub sijhawm hardening, ua rau cov ntim tsis sib npaug, ua rau muaj kab nrib pleb. Cov khoom khaws dej ntawm HPMC ua lub luag haujlwm tseem ceeb hauv qhov no:
Ua kom cov dej noo qeeb: HPMC khaws cov dej noo hauv cov cement slurry, yog li ua kom qeeb qeeb ntawm cov dej noo. Qhov kev khaws cia dej no tsis yog tsuas yog pab ua kom lub sijhawm ua kom cov dej noo ntev dua, tab sis kuj txo qhov qhuav qhuav uas tshwm sim los ntawm cov dej noo.
Cov tshuaj tiv thaiv dej sib xws: Vim tias HPMC muab ib puag ncig dej ruaj khov, cov cement me me tuaj yeem dhau los ua cov tshuaj tiv thaiv dej sib xws thiab txaus, txo qhov sib txawv ntawm kev ntxhov siab sab hauv thiab txo qhov kev pheej hmoo ntawm kev tawg los ntawm kev qhuav ntsws.
2. Txhim kho qhov viscosity thiab kev faib tawm ntawm cov ntaub ntawv
HPMC muaj cov nyhuv tuab, uas ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua haujlwm thiab kev sib xws ntawm cov ntaub ntawv cement:
Nce Viscosity: HPMC ua rau kom cov viscosity ntawm cov slurry nce ntxiv, txhim kho kev ua haujlwm thaum lub sijhawm thov, cia cov slurry ntws zoo dua thiab sau cov pwm lossis cov kab nrib pleb, txo cov voids thiab thaj chaw tsis sib xws.
Kev faib tawm sib xws: Los ntawm kev nce qhov viscosity ntawm cov slurry, HPMC ua rau kev faib tawm ntawm cov fillers thiab fibers hauv cov slurry ntau dua, ua rau muaj cov qauv sab hauv sib xws thaum lub sijhawm ua kom tawv thiab txo qhov tawg vim muaj kev ntxhov siab hauv zos.
3. Txhim kho cov khoom tsim zaj duab xis thiab kev tiv thaiv nto
Cov khoom tsim zaj duab xis ntawm HPMC pab tsim ib txheej tiv thaiv rau ntawm qhov chaw ntawm cov khoom, uas muaj cov txiaj ntsig zoo rau kev txo cov kab nrib pleb ntawm qhov chaw:
Kev tiv thaiv nto: Cov txheej zaj duab xis yooj ywm uas tsim los ntawm HPMC ntawm qhov chaw ntawm cov khoom tuaj yeem tiv thaiv qhov chaw ntawm kev yaig los ntawm ib puag ncig sab nraud thiab kev poob dej sai, yog li txo qhov tshwm sim ntawm cov kab nrib pleb saum npoo.
Kev npog yooj ywm: Cov txheej zaj duab xis no muaj qee qib ntawm kev ywj pheej thiab tuaj yeem nqus tau ib feem ntawm kev ntxhov siab thaum lub sijhawm me ntsis deformation, yog li tiv thaiv lossis qeeb qeeb qhov kev nthuav dav ntawm cov kab nrib pleb.
4. Tswj cov txheej txheem dej
HPMC tuaj yeem tswj cov txheej txheem hydration ntawm cement, uas ua lub luag haujlwm tseem ceeb hauv kev txo qhov kev ntxhov siab los ntawm kev tsis sib xws ntawm cov dej:
Kev tso dej qeeb qeeb: HPMC tuaj yeem txo qhov kev ua kom dej sai sai, ua rau cov dej hauv cov cement slurry maj mam tso tawm, yog li muab qhov chaw ua kom dej sib xws thiab ruaj khov dua. Qhov kev tso dej qeeb no txo cov kev ntxhov siab uas tshwm sim los ntawm cov tshuaj tiv thaiv dej tsis sib xws, yog li txo qhov kev pheej hmoo ntawm kev tawg.
Cov piv txwv ntawm kev siv HPMC hauv cov ntaub ntawv sib txawv raws li cement
HPMC siv dav hauv cov ntaub ntawv ua los ntawm cement, suav nrog tab sis tsis txwv rau cov plag tsev uas nws tus kheej leveling, cov txheej txheem phab ntsa sab nraud, cov mortars thiab cov ntaub ntawv kho pob zeb. Cov hauv qab no yog qee qhov piv txwv ntawm kev siv tshwj xeeb:
1. Cov ntaub ntawv hauv pem teb uas nws tus kheej leveling
Cov ntaub ntawv hauv pem teb uas nws tus kheej leveling xav tau kev fluidity zoo thiab cov khoom sib txuas thaum tiv thaiv kev tawg ntawm qhov chaw. HPMC txhim kho kev ntws thiab qhov chaw tiav ntawm cov khoom los ntawm nws cov thickening thiab dej tuav cov teebmeem thaum txo qhov tshwm sim ntawm cov kab nrib pleb ntawm qhov chaw.
2. Xim pleev rau phab ntsa sab nraud
Cov xim pleev sab nraud xav tau kev nplaum zoo thiab tiv taus kev tawg. Cov yam ntxwv ntawm kev tsim zaj duab xis thiab kev khaws dej ntawm HPMC txhim kho qhov kev nplaum thiab kev ywj pheej ntawm cov txheej, yog li ua kom cov txheej tiv taus kev tawg thiab kev tiv taus huab cua.
3. Cov ntaub ntawv kho
Cov ntaub ntawv kho pob zeb yuav tsum muaj zog thiab tawv sai thaum tseem tswj tau qhov qhuav qis. HPMC muab cov peev xwm khaws dej zoo heev thiab tswj tau dej noo, uas ua rau cov ntaub ntawv kho kom tswj tau qhov qhuav qis thaum lub sijhawm ua kom tawv thiab txo qhov kev pheej hmoo ntawm kev tawg tom qab kho.
Cov kev ceev faj rau kev siv HPMC
Txawm hais tias HPMC muaj cov txiaj ntsig zoo hauv kev txo qhov tawg ntawm cov ntaub ntawv cement, cov ntsiab lus hauv qab no tseem yuav tsum tau sau tseg thaum siv:
Kev tswj cov tshuaj: Cov tshuaj HPMC yuav tsum ua raws li cov qauv uas yuav tsum tau ua. Ntau dhau lossis tsawg dhau yuav cuam tshuam rau kev ua haujlwm ntawm cov khoom. Feem ntau, cov tshuaj yog nyob nruab nrab ntawm 0.1% - 0.5%.
Kev Sib Xyaws Sib Xws: HPMC yuav tsum tau sib xyaw kom huv si nrog lwm cov ntaub ntawv kom ntseeg tau tias nws ua haujlwm thoob plaws hauv cov slurry.
Cov xwm txheej ntawm kev tsim kho: Qhov chaw tsim kho (xws li qhov kub thiab txias, av noo) kuj muaj feem cuam tshuam rau qhov cuam tshuam ntawm HPMC, thiab yuav tsum tau kho kom haum raws li cov xwm txheej tshwj xeeb.
Ua ib qho tshuaj ntxiv zoo rau cov khoom siv cement, HPMC ua lub luag haujlwm tseem ceeb hauv kev txo qhov tawg ntawm cov khoom siv cement los ntawm nws cov yam ntxwv tshwj xeeb ntawm kev khaws dej, kev ua kom tuab, kev tsim zaj duab xis thiab kev tswj hwm dej. Nws ncua kev ua kom dej noo, txhim kho kev sib npaug ntawm cov khoom siv, tiv thaiv cov khoom siv, thiab tswj cov txheej txheem dej, yog li txo qhov kev pheej hmoo ntawm kev tawg. Yog li ntawd, thaum siv cov khoom siv cement, kev siv HPMC kom zoo tsis tsuas yog txhim kho kev ua haujlwm ntawm cov khoom siv, tab sis kuj txuas ntxiv nws lub neej kev pabcuam thiab txo cov nqi txij nkawm.
Lub sijhawm tshaj tawm: Lub Rau Hli-26-2024