Hydroxypropyl methylcellulose (HPMC) yog ib qho cellulose ether uas siv tau ntau yam hauv kev lag luam kev tsim kho, tshwj xeeb tshaj yog hauv cov qauv mortar qhuav. Nws cov yam ntxwv tshwj xeeb ua rau kev ua haujlwm thiab kev tuav cov mortars zoo dua, pab txhawb rau lawv txoj kev ua haujlwm zoo.
Cov Qauv Tshuaj thiab Kev Sib Xyaws
HPMC yog muab los ntawm cellulose, ib qho polymer ntuj pom nyob rau hauv cov phab ntsa ntawm cov nroj tsuag. Nws yog synthesized los ntawm etherification ntawm cellulose nrog methyl chloride thiab propylene oxide. Cov txheej txheem no hloov qee cov hydroxyl pawg hauv cov cellulose molecule nrog methoxy (-OCH₃) thiab hydroxypropyl (-OCH₂CH(OH)CH₃) pawg. Qhov degree ntawm kev hloov pauv thiab qhov piv ntawm methoxy rau hydroxypropyl pawg txiav txim siab cov khoom tshwj xeeb ntawm HPMC, xws li solubility, viscosity, thiab thermal gelation.
Cov Khoom ntawm HPMC hauv Dry-Mix Mortar
1. Kev Khaws Dej
HPMC muaj txiaj ntsig zoo heev rau kev khaws cov dej hauv cov mortar sib xyaw. Qhov kev khaws cov dej no yog qhov tseem ceeb vim nws ua kom cov cement noo zoo, ua kom cov txheej txheem kho zoo dua. Kev khaws cov dej zoo dua ua rau ua haujlwm tau zoo dua thiab qhib lub sijhawm ntev dua, txo qhov kev pheej hmoo ntawm kev qhuav ua ntej, uas tuaj yeem ua rau ntsws thiab tawg. Tsis tas li ntawd, nws ua kom muaj dej txaus rau cov cement noo, txhim kho cov khoom siv kho tshuab thiab lub zog ntawm cov mortar.
2. Kev Hloov Kho Rheology
HPMC hloov pauv qhov rheology ntawm cov mortars qhuav. Nws ua haujlwm ua ib qho thickener, ua rau cov viscosity ntawm cov mortar sib tov nce ntxiv. Cov yam ntxwv no yog qhov tseem ceeb rau kev tswj cov dej ntws thiab kev nthuav dav ntawm cov mortar, ua rau nws yooj yim dua rau kev siv rau ntawm cov chaw ntsug yam tsis muaj sagging. Nws kuj pab ua kom tiav cov khaubncaws sab nraud povtseg du thiab sib npaug thaum lub sijhawm siv, ua kom ntseeg tau tias muaj kev sib txuas zoo dua thiab sib koom ua ke. Kev hloov pauv rheological los ntawm HPMC txhim kho kev tuav thiab kev siv cov yam ntxwv ntawm cov mortar.
3. Kev Txhim Kho Kev Sib Txuas
HPMC ua kom cov khoom nplaum ntawm cov mortar qhuav zoo dua. Nws txhim kho lub zog sib txuas ntawm cov mortar thiab ntau yam substrates xws li cib, pob zeb, thiab vuas. Qhov no tseem ceeb heev rau cov ntawv thov xws li cov nplaum vuas thiab cov txheej txheem rwb thaiv tsev sab nraud. Qhov kev nplaum zoo dua txo qhov yuav tshwm sim ntawm kev tawg thiab ua kom ntseeg tau tias cov mortar siv tau ntev.
4. Kev ua haujlwm tau zoo thiab kev sib xws
Ib qho ntawm cov txiaj ntsig tseem ceeb ntawm HPMC yog kev txhim kho hauv kev ua haujlwm thiab kev sib xws ntawm cov mortars qhuav. Nws tso cai rau kev sib tov yooj yim thiab kev siv du, muab cov qauv creamy uas yooj yim rau kev nthuav dav thiab duab. Kev ua haujlwm zoo dua txo qhov kev siv zog thaum lub sijhawm thov, ua rau cov txheej txheem ua haujlwm tau zoo dua thiab tsis tas siv zog ntau. Nws kuj ua kom ntseeg tau tias cov mortar faib tau zoo dua, ua rau cov tiav zoo dua.
5. Kev Ua Kub Kub
HPMC muaj cov yam ntxwv thermal gelation, uas txhais tau tias nws tsim cov gel thaum raug cua sov. Cov yam ntxwv no muaj txiaj ntsig zoo rau cov ntawv thov uas xav tau kev tiv thaiv cua sov. Thaum lub sijhawm siv cov mortar, cov cua sov tsim tawm tuaj yeem ua rau muaj kev nce ntxiv ntawm viscosity, uas pab tswj cov duab thiab kev ruaj khov ntawm cov mortar siv. Thaum qhov kub poob qis, cov gel rov qab mus rau nws lub xeev qub, ua rau nws ua haujlwm tau txuas ntxiv.
6. Kev Nkag Mus Rau Huab Cua
HPMC tuaj yeem ua rau cov pa me me hauv cov mortar sib xyaw thiab ruaj khov. Qhov cua nkag no txhim kho qhov kev tiv thaiv khov-thaw ntawm cov mortar los ntawm kev muab qhov chaw rau cov dej khov ua kom nthuav dav, txo qhov siab sab hauv thiab tiv thaiv kev puas tsuaj. Tsis tas li ntawd, cov cua nkag ua rau kev ua haujlwm thiab kev nqus dej ntawm cov mortar, ua rau nws yooj yim dua rau kev siv rau ntau yam xwm txheej.
7. Kev Sib Piv Nrog Lwm Cov Khoom Siv Ntxiv
HPMC sib xws nrog ntau yam khoom siv ntxiv uas feem ntau siv rau hauv cov mortars qhuav, xws li superplasticizers, retarders, thiab accelerators. Qhov kev sib xws no tso cai rau kev tsim cov khoom sib xyaw ua ke kom ua tau raws li qhov xav tau kev ua tau zoo tshwj xeeb. Piv txwv li, HPMC tuaj yeem ua haujlwm sib koom tes nrog superplasticizers los txhim kho kev ntws thaum tswj hwm qhov viscosity xav tau.
8. Kev Tsim Yeeb Yam
HPMC tsim ib daim zaj duab xis nyias nyias, yoog tau thaum ziab, uas pab txhawb rau cov yam ntxwv ntawm cov mortar. Daim zaj duab xis no pab tswj kev ua kom dej noo thiab ua kom lub zog thiab kev ruaj khov ntawm cov mortar. Nws kuj muab ib txheej tiv thaiv uas tuaj yeem txhim kho kev tiv thaiv huab cua thiab kev tiv thaiv kev sib txhuam ntawm cov mortar siv.
9. Kev Tiv Thaiv Ib puag ncig
HPMC tiv taus ntau yam ib puag ncig, suav nrog cov dej noo, qhov kub thiab txias hloov pauv, thiab kev raug tshuaj lom neeg. Qhov kev tiv taus no yog qhov tseem ceeb rau kev ruaj khov thiab lub neej ntev ntawm cov mortars qhuav, tshwj xeeb tshaj yog nyob rau hauv qhov xwm txheej ib puag ncig hnyav lossis hloov pauv. Nws pab tswj kev ua haujlwm thiab qhov zoo li ntawm cov mortar dhau sijhawm, txo qhov xav tau kev saib xyuas lossis kho ntau zaus.
10. Kev Siv Tshuaj thiab Daim Ntawv Thov
Feem ntau, HPMC siv rau hauv cov hmoov sib xyaw qhuav. Qhov ntau npaum li cas ntawm HPMC nyob ntawm seb koj xav tau dab tsi thiab hom kev siv. Piv txwv li, cov tshuaj ntau dua yuav siv tau rau hauv cov nplaum rau pobzeb kom txhim kho kev nplaum thiab kev ua haujlwm tau zoo, thaum cov tshuaj tsawg dua yuav txaus rau cov hmoov sib xyaw dav dav. Kev siv HPMC rau hauv cov hmoov sib xyaw qhuav yooj yim heev, thiab nws tuaj yeem yooj yim tawg thaum lub sijhawm sib tov.
HPMC yog ib qho khoom tseem ceeb hauv cov mortars qhuav vim nws muaj ntau yam khoom siv. Nws lub peev xwm khaws dej, hloov kho rheology, txhim kho kev nplaum, txhim kho kev ua haujlwm, thiab muab kev tiv thaiv ib puag ncig ua rau nws yog ib qho khoom siv ntxiv rau ntau yam kev siv hauv kev tsim kho. Los ntawm kev nkag siab thiab siv cov yam ntxwv yooj yim ntawm HPMC, cov neeg tsim qauv tuaj yeem tsim cov mortars qhuav ua tau zoo uas ua tau raws li ntau yam kev xav tau ntawm kev siv niaj hnub no.
Lub sijhawm tshaj tawm: Lub Rau Hli-14-2024