HPMC (Hydroxypropyl methylcellulose)yog ib qho kev siv lub tsev admixture thiab yog dav siv nyob rau hauv gypsum mortar. Nws lub luag haujlwm tseem ceeb yog txhawm rau txhim kho kev tsim kho ntawm mortar, txhim kho dej tuav, txhim kho adhesion thiab kho cov khoom rheological ntawm mortar. Gypsum mortar yog cov khoom siv hauv tsev nrog gypsum ua cov khoom tseem ceeb, uas feem ntau siv rau hauv phab ntsa thiab qab nthab kho kom zoo nkauj.
1. Cov nyhuv ntawm HPMC ntau npaum li cas ntawm cov dej tuav ntawm gypsum mortar
Kev tuav dej yog ib qho ntawm cov khoom tseem ceeb ntawm gypsum mortar, uas yog ncaj qha ntsig txog kev tsim kho thiab kev sib txuas ntawm lub zog ntawm mortar. HPMC, raws li lub siab molecular polymer, muaj dej tuav zoo. Nws cov molecules muaj ntau ntawm hydroxyl thiab ether pawg. Cov pab pawg hydrophilic no tuaj yeem tsim cov ntawv cog lus hydrogen nrog cov dej molecules los txo cov dej volatilization. Yog li ntawd, qhov sib ntxiv ntawm qhov tsim nyog ntawm HPMC tuaj yeem txhim kho cov dej khaws cia ntawm mortar thiab tiv thaiv cov mortar kom qhuav sai heev thiab tawg ntawm qhov chaw thaum tsim kho.
Cov kev tshawb fawb tau pom tias nrog qhov nce ntawm HPMC ntau npaum li cas, cov dej khaws cia ntawm cov tshuaj khib nyiab maj mam nce. Txawm li cas los xij, thaum ntau npaum li cas siab dhau lawm, rheology ntawm mortar yuav loj dhau, cuam tshuam rau kev tsim kho. Yog li ntawd, qhov kev pom zoo ntawm HPMC yuav tsum tau hloov kho raws li kev siv tiag tiag.
2. Qhov cuam tshuam ntawm HPMC ntau npaum li cas ntawm kev sib txuas lub zog ntawm gypsum mortar
Bonding lub zog yog lwm qhov kev ua haujlwm tseem ceeb ntawm gypsum mortar, uas cuam tshuam ncaj qha rau qhov adhesion ntawm cov tshuaj khib thiab lub hauv paus. HPMC, raws li lub siab molecular polymer, tuaj yeem txhim kho kev sib koom ua ke thiab kev sib koom ua ke ntawm mortar. Qhov zoo ntawm HPMC tuaj yeem txhim kho kev sib txuas ntawm cov mortar, kom nws tuaj yeem tsim kom muaj zog adhesion nrog phab ntsa thiab substrate thaum lub sij hawm tsim kho.
Cov kev tshawb fawb soj ntsuam tau pom tias qhov ntau npaum li cas ntawm HPMC muaj qhov cuam tshuam loj rau kev sib txuas ntawm cov tshuaj khib nyiab. Thaum HPMC ntau npaum li cas nyob rau hauv ib qho chaw (feem ntau 0.2%-0.6%), lub zog sib txuas qhia tau hais tias muaj kev nce siab. Qhov no yog vim HPMC tuaj yeem txhim kho cov yas ntawm cov mortar, kom nws tuaj yeem ua tau zoo dua rau lub substrate thaum tsim kho thiab txo qis thiab tawg. Txawm li cas los xij, yog tias qhov ntau npaum li cas siab dhau lawm, cov tshuaj khib nyiab tuaj yeem muaj cov kua dej ntau dhau, cuam tshuam rau nws qhov adhesion rau lub substrate, yog li txo qhov kev sib txuas ntawm lub zog.
3. Cov nyhuv ntawm HPMC ntau npaum li cas ntawm cov dej ntws thiab kev tsim kho ntawm gypsum mortar
Fluidity yog ib qho tseem ceeb ntawm kev ua tau zoo hauv cov txheej txheem kev tsim kho ntawm gypsum mortar, tshwj xeeb tshaj yog nyob rau thaj tsam loj ntawm phab ntsa. Qhov sib ntxiv ntawm HPMC tuaj yeem txhim kho qhov fluidity ntawm mortar, ua kom yooj yim rau kev tsim thiab ua haujlwm. Cov yam ntxwv ntawm HPMC cov qauv molecular ua rau nws nce viscosity ntawm mortar los ntawm thickening, yog li txhim kho kev ua haujlwm thiab kev tsim kho ntawm mortar.
Thaum HPMC ntau npaum li cas, qhov fluidity ntawm mortar tsis zoo, uas yuav ua rau muaj teeb meem kev tsim kho thiab txawm tias tawg. Qhov tsim nyog ntawm HPMC ntau npaum li cas (feem ntau ntawm 0.2% -0.6%) tuaj yeem txhim kho cov kua dej ntawm cov tshuaj khib nyiab, txhim kho nws cov txheej txheem kev ua tau zoo thiab ua kom zoo dua qub, thiab yog li txhim kho kev tsim kho. Txawm li cas los xij, yog tias qhov ntau npaum li cas, qhov fluidity ntawm mortar yuav dhau los ua viscous, kev tsim kho yuav nyuaj, thiab nws yuav ua rau cov khoom pov tseg.
4. Cov nyhuv ntawm HPMC ntau npaum li cas ntawm kev ziab shrinkage ntawm gypsum mortar
Qhuav shrinkage yog lwm yam khoom tseem ceeb ntawm gypsum mortar. Cov shrinkage ntau dhau yuav ua rau tawg ntawm phab ntsa. Qhov sib ntxiv ntawm HPMC tuaj yeem txo qhov ziab kom qhuav ntawm mortar. Txoj kev tshawb nrhiav pom tias qhov tsim nyog tus nqi ntawm HPMC tuaj yeem txo cov evaporation sai ntawm cov dej, yog li alleviating lub drying shrinkage teeb meem ntawm gypsum mortar. Tsis tas li ntawd, cov qauv molecular ntawm HPMC tuaj yeem tsim cov qauv sib txuas ruaj khov, ntxiv rau kev txhim kho qhov tawg ntawm cov mortar.
Txawm li cas los xij, yog tias qhov ntau npaum li cas ntawm HPMC siab dhau lawm, nws yuav ua rau lub mortar teem sijhawm ntev, cuam tshuam rau kev tsim kho. Nyob rau tib lub sijhawm, qhov viscosity siab tuaj yeem ua rau cov dej tsis sib xws thaum tsim kho, cuam tshuam rau kev txhim kho ntawm shrinkage.
5. Cov nyhuv ntawm HPMC ntau npaum li cas ntawm kev tawg ntawm gypsum mortar
Crack kuj yog ib qho tseem ceeb qhia rau kev ntsuam xyuas qhov zoo ntawm gypsum mortar. HPMC tuaj yeem txhim kho nws qhov kev sib tsoo los ntawm kev txhim kho lub zog compressive, adhesion thiab toughness ntawm mortar. Los ntawm kev ntxiv qhov tsim nyog ntawm HPMC, qhov tawg tsis kam ntawm gypsum mortar tuaj yeem txhim kho tau zoo kom tsis txhob muaj cov kab nrib pleb los ntawm kev quab yuam sab nraud lossis qhov kub thiab txias.
Qhov kev pom zoo ntawm HPMC feem ntau yog nyob nruab nrab ntawm 0.3% thiab 0.5%, uas tuaj yeem txhim kho cov txheej txheem toughness ntawm mortar thiab txo cov kab nrib pleb los ntawm qhov kub thiab txias. Txawm li cas los xij, yog tias qhov ntau npaum li cas, qhov viscosity ntau dhau yuav ua rau cov tshuaj khib kom kho tau qeeb dhau, yog li cuam tshuam rau nws qhov kev sib tsoo tag nrho.
6. Kev ua kom zoo thiab siv tau ntawm HPMC ntau npaum li cas
Los ntawm kev txheeb xyuas ntawm cov ntsuas kev ua tau zoo saum toj no, qhov ntau npaum li casHPMCmuaj qhov cuam tshuam loj rau kev ua haujlwm ntawm gypsum mortar. Txawm li cas los xij, qhov ntau npaum li cas yog qhov sib npaug, thiab qhov ntau npaum li cas feem ntau pom zoo kom yog 0.2% txog 0.6%. Qhov sib txawv ntawm kev tsim kho thiab kev siv cov kev cai yuav xav tau kev hloov kho rau ntau npaum li cas kom ua tiav qhov kev ua tau zoo tshaj plaws. Hauv kev siv tswv yim, ntxiv rau qhov ntau npaum li cas ntawm HPMC, lwm yam yuav tsum tau xav txog, xws li kev faib ua feem ntawm mortar, cov khoom ntawm lub substrate, thiab kev tsim kho.
Qhov ntau npaum ntawm HPMC muaj qhov cuam tshuam loj rau kev ua haujlwm ntawm gypsum mortar. Qhov tsim nyog tus nqi ntawm HPMC tuaj yeem txhim kho cov khoom tseem ceeb ntawm cov tshuaj khib nyiab xws li dej tuav, kev sib txuas lub zog, fluidity, thiab tawg tsis kam. Kev tswj ntawm qhov ntau npaum li cas yuav tsum ua tib zoo xav txog qhov yuav tsum tau ua ntawm kev tsim kho thiab qhov kawg lub zog ntawm mortar. Qhov tsim nyog HPMC ntau npaum li cas tuaj yeem tsis tsuas yog txhim kho kev tsim kho ntawm mortar, tab sis kuj txhim kho kev ua haujlwm ntev ntawm mortar. Yog li ntawd, hauv kev tsim khoom thiab kev tsim kho tiag tiag, ntau npaum li cas ntawm HPMC yuav tsum tau ua kom zoo raws li cov kev xav tau tshwj xeeb kom ua tiav cov txiaj ntsig zoo tshaj plaws.
Post lub sij hawm: Dec-16-2024